[compiler][optim] Add shape for Array.from

(see title)

.codesandbox/ci.json

@@ -1,11 +1,10 @@
 {
-  "packages": ["packages/react", "packages/react-dom", "packages/react-server-dom-webpack", "packages/scheduler"],
+  "packages": ["packages/react", "packages/react-dom", "packages/scheduler"],
   "buildCommand": "download-build-in-codesandbox-ci",
   "node": "18",
   "publishDirectory": {
     "react": "build/oss-experimental/react",
     "react-dom": "build/oss-experimental/react-dom",
-    "react-server-dom-webpack": "build/oss-experimental/react-server-dom-webpack",
     "scheduler": "build/oss-experimental/scheduler"
   },
   "sandboxes": ["new"],

.eslintrc.js

@@ -474,7 +474,7 @@ module.exports = {
     {
       files: ['packages/react-server-dom-turbopack/**/*.js'],
       globals: {
-        __turbopack_load_by_url__: 'readonly',
+        __turbopack_load__: 'readonly',
         __turbopack_require__: 'readonly',
       },
     },
@@ -496,7 +496,6 @@ module.exports = {
         'packages/react-devtools-shared/src/devtools/views/**/*.js',
         'packages/react-devtools-shared/src/hook.js',
         'packages/react-devtools-shared/src/backend/console.js',
-        'packages/react-devtools-shared/src/backend/fiber/renderer.js',
         'packages/react-devtools-shared/src/backend/shared/DevToolsComponentStackFrame.js',
         'packages/react-devtools-shared/src/frontend/utils/withPermissionsCheck.js',
       ],
@@ -505,7 +504,6 @@ module.exports = {
         __IS_FIREFOX__: 'readonly',
         __IS_EDGE__: 'readonly',
         __IS_NATIVE__: 'readonly',
-        __IS_INTERNAL_MCP_BUILD__: 'readonly',
         __IS_INTERNAL_VERSION__: 'readonly',
         chrome: 'readonly',
       },
@@ -561,7 +559,6 @@ module.exports = {
     ConsoleTask: 'readonly', // TOOD: Figure out what the official name of this will be.
     ReturnType: 'readonly',
     AnimationFrameID: 'readonly',
-    WeakRef: 'readonly',
     // For Flow type annotation. Only `BigInt` is valid at runtime.
     bigint: 'readonly',
     BigInt: 'readonly',
@@ -582,7 +579,6 @@ module.exports = {
     JSONValue: 'readonly',
     JSResourceReference: 'readonly',
     MouseEventHandler: 'readonly',
-    NavigateEvent: 'readonly',
     PropagationPhases: 'readonly',
     PropertyDescriptor: 'readonly',
     React$AbstractComponent: 'readonly',
@@ -608,12 +604,10 @@ module.exports = {
     symbol: 'readonly',
     SyntheticEvent: 'readonly',
     SyntheticMouseEvent: 'readonly',
-    SyntheticPointerEvent: 'readonly',
     Thenable: 'readonly',
     TimeoutID: 'readonly',
     WheelEventHandler: 'readonly',
     FinalizationRegistry: 'readonly',
-    Exclude: 'readonly',
     Omit: 'readonly',
     Keyframe: 'readonly',
     PropertyIndexedKeyframes: 'readonly',
@@ -621,9 +615,6 @@ module.exports = {
     GetAnimationsOptions: 'readonly',
     Animatable: 'readonly',
     ScrollTimeline: 'readonly',
-    EventListenerOptionsOrUseCapture: 'readonly',
-    FocusOptions: 'readonly',
-    OptionalEffectTiming: 'readonly',
 
     spyOnDev: 'readonly',
     spyOnDevAndProd: 'readonly',
@@ -641,6 +632,5 @@ module.exports = {
     AsyncLocalStorage: 'readonly',
     async_hooks: 'readonly',
     globalThis: 'readonly',
-    navigation: 'readonly',
   },
 };

.github/ISSUE_TEMPLATE/19.md

@@ -0,0 +1,18 @@
+---
+name: "⚛React 19 beta issue"
+about: Report a issue with React 19 beta.
+title: '[React 19]'
+labels: 'React 19'
+
+---
+
+
+## Summary
+
+<!--
+  Please provide a CodeSandbox (https://codesandbox.io/s/new), a link to a
+  repository on GitHub, or provide a minimal code example that reproduces the
+  problem. You may provide a screenshot of the application if you think it is
+  relevant to your bug report. Here are some tips for providing a minimal
+  example: https://stackoverflow.com/help/mcve.
+-->

.github/workflows/compiler_discord_notify.yml

@@ -7,28 +7,9 @@ on:
       - compiler/**
       - .github/workflows/compiler_**.yml
 
-permissions: {}
-
 jobs:
-  check_access:
-    if: ${{ github.event.pull_request.draft == false }}
-    runs-on: ubuntu-latest
-    outputs:
-      is_member_or_collaborator: ${{ steps.check_is_member_or_collaborator.outputs.is_member_or_collaborator }}
-    steps:
-      - run: echo ${{ github.event.pull_request.author_association }}
-      - name: Check is member or collaborator
-        id: check_is_member_or_collaborator
-        if: ${{ github.event.pull_request.author_association == 'MEMBER' || github.event.pull_request.author_association == 'COLLABORATOR' }}
-        run: echo "is_member_or_collaborator=true" >> "$GITHUB_OUTPUT"
-
   check_maintainer:
-    if: ${{ needs.check_access.outputs.is_member_or_collaborator == 'true' || needs.check_access.outputs.is_member_or_collaborator == true }}
-    needs: [check_access]
     uses: facebook/react/.github/workflows/shared_check_maintainer.yml@main
-    permissions:
-      # Used by check_maintainer
-      contents: read
     with:
       actor: ${{ github.event.pull_request.user.login }}
 
@@ -38,7 +19,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Discord Webhook Action
-        uses: tsickert/discord-webhook@86dc739f3f165f16dadc5666051c367efa1692f4
+        uses: tsickert/discord-webhook@v6.0.0
         with:
           webhook-url: ${{ secrets.COMPILER_DISCORD_WEBHOOK_URL }}
           embed-author-name: ${{ github.event.pull_request.user.login }}

.github/workflows/compiler_playground.yml

@@ -8,8 +8,6 @@ on:
       - compiler/**
       - .github/workflows/compiler_playground.yml
 
-permissions: {}
-
 concurrency:
   group: ${{ github.workflow }}-${{ github.ref_name }}-${{ github.event.pull_request.number || github.run_id }}
   cancel-in-progress: true
@@ -38,27 +36,10 @@ jobs:
         uses: actions/cache@v4
         id: node_modules
         with:
-          path: |
-            **/node_modules
-          key: compiler-and-playground-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('compiler/**/yarn.lock') }}
+          path: "**/node_modules"
+          key: compiler-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('compiler/**/yarn.lock') }}
       - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
-        working-directory: compiler
-      - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
-      - name: Check Playwright version
-        id: playwright_version
-        run: echo "playwright_version=$(npm ls @playwright/test | grep @playwright | sed 's/.*@//' | head -1)" >> "$GITHUB_OUTPUT"
-      - name: Cache Playwright Browsers for version ${{ steps.playwright_version.outputs.playwright_version }}
-        id: cache_playwright_browsers
-        uses: actions/cache@v4
-        with:
-          path: ~/.cache/ms-playwright
-          key: playwright-browsers-v6-${{ runner.arch }}-${{ runner.os }}-${{ steps.playwright_version.outputs.playwright_version }}
       - run: npx playwright install --with-deps chromium
-        if: steps.cache_playwright_browsers.outputs.cache-hit != 'true'
-      - run: npx playwright install-deps
-        if: steps.cache_playwright_browsers.outputs.cache-hit == 'true'
       - run: CI=true yarn test
       - run: ls -R test-results
         if: '!cancelled()'
@@ -68,4 +49,3 @@ jobs:
         with:
           name: test-results
           path: compiler/apps/playground/test-results
-          if-no-files-found: ignore

.github/workflows/compiler_prereleases.yml

@@ -16,19 +16,15 @@ on:
       version_name:
         required: true
         type: string
-      tag_version:
-        required: false
-        type: string
     secrets:
       NPM_TOKEN:
         required: true
 
-permissions: {}
-
 env:
   TZ: /usr/share/zoneinfo/America/Los_Angeles
   # https://github.com/actions/cache/blob/main/tips-and-workarounds.md#cache-segment-restore-timeout
   SEGMENT_DOWNLOAD_TIMEOUT_MINS: 1
+  GH_TOKEN: ${{ github.token }}
   NPM_TOKEN: ${{ secrets.NPM_TOKEN }}
 
 defaults:
@@ -50,12 +46,10 @@ jobs:
         uses: actions/cache@v4
         id: node_modules
         with:
-          path: |
-            **/node_modules
-          key: compiler-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('compiler/yarn.lock') }}
+          path: "**/node_modules"
+          key: compiler-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('compiler/**/yarn.lock') }}
       - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
       - name: Publish packages to npm
         run: |
           cp ./scripts/release/ci-npmrc ~/.npmrc
-          scripts/release/publish.js --frfr --ci --versionName=${{ inputs.version_name }} --tag=${{ inputs.dist_tag }} ${{ inputs.tag_version && format('--tagVersion={0}', inputs.tag_version) || '' }}
+          scripts/release/publish.js --frfr --ci --versionName=${{ inputs.version_name }} --tag ${{ inputs.dist_tag }}

.github/workflows/compiler_prereleases_manual.yml

@@ -14,11 +14,6 @@ on:
       version_name:
         required: true
         type: string
-      tag_version:
-        required: false
-        type: string
-
-permissions: {}
 
 env:
   TZ: /usr/share/zoneinfo/America/Los_Angeles
@@ -32,6 +27,5 @@ jobs:
       release_channel: ${{ inputs.release_channel }}
       dist_tag: ${{ inputs.dist_tag }}
       version_name: ${{ inputs.version_name }}
-      tag_version: ${{ inputs.tag_version }}
     secrets:
       NPM_TOKEN: ${{ secrets.NPM_TOKEN }}

.github/workflows/compiler_prereleases_nightly.yml

@@ -5,8 +5,6 @@ on:
     # At 10 minutes past 16:00 on Mon, Tue, Wed, Thu, and Fri
     - cron: 10 16 * * 1,2,3,4,5
 
-permissions: {}
-
 env:
   TZ: /usr/share/zoneinfo/America/Los_Angeles
 

.github/workflows/compiler_prereleases_weekly.yml

@@ -0,0 +1,21 @@
+name: (Compiler) Publish Prereleases Weekly
+
+on:
+  schedule:
+    # At 10 minutes past 9:00 on Mon
+    - cron: 10 9 * * 1
+
+env:
+  TZ: /usr/share/zoneinfo/America/Los_Angeles
+
+jobs:
+  publish_prerelease_beta:
+    name: Publish to beta channel
+    uses: facebook/react/.github/workflows/compiler_prereleases.yml@main
+    with:
+      commit_sha: ${{ github.sha }}
+      release_channel: beta
+      dist_tag: beta
+      version_name: '19.0.0'
+    secrets:
+      NPM_TOKEN: ${{ secrets.NPM_TOKEN }}

.github/workflows/compiler_typescript.yml

@@ -8,8 +8,6 @@ on:
       - compiler/**
       - .github/workflows/compiler_typescript.yml
 
-permissions: {}
-
 concurrency:
   group: ${{ github.workflow }}-${{ github.ref_name }}-${{ github.event.pull_request.number || github.run_id }}
   cancel-in-progress: true
@@ -47,13 +45,10 @@ jobs:
           cache-dependency-path: compiler/yarn.lock
       - name: Restore cached node_modules
         uses: actions/cache@v4
-        id: node_modules
         with:
-          path: |
-            **/node_modules
-          key: compiler-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('compiler/yarn.lock') }}
+          path: "**/node_modules"
+          key: compiler-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('compiler/**/yarn.lock') }}
       - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
       - run: yarn workspace babel-plugin-react-compiler lint
 
   # Hardcoded to improve parallelism
@@ -71,11 +66,9 @@ jobs:
         uses: actions/cache@v4
         id: node_modules
         with:
-          path: |
-            **/node_modules
-          key: compiler-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('compiler/yarn.lock') }}
+          path: "**/node_modules"
+          key: compiler-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('compiler/**/yarn.lock') }}
       - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
       - run: yarn workspace babel-plugin-react-compiler jest
 
   test:
@@ -97,11 +90,9 @@ jobs:
         uses: actions/cache@v4
         id: node_modules
         with:
-          path: |
-            **/node_modules
-          key: compiler-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('compiler/yarn.lock') }}
+          path: "**/node_modules"
+          key: compiler-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('compiler/**/yarn.lock') }}
       - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
       - run: xvfb-run -a yarn workspace ${{ matrix.workspace_name }} test
         if: runner.os == 'Linux' && matrix.workspace_name == 'react-forgive'
       - run: yarn workspace ${{ matrix.workspace_name }} test

.github/workflows/devtools_regression_tests.yml

@@ -9,8 +9,6 @@ on:
         required: false
         type: string
 
-permissions: {}
-
 env:
   TZ: /usr/share/zoneinfo/America/Los_Angeles
   # https://github.com/actions/cache/blob/main/tips-and-workarounds.md#cache-segment-restore-timeout
@@ -20,9 +18,6 @@ jobs:
   download_build:
     name: Download base build
     runs-on: ubuntu-latest
-    permissions:
-      # We use github.token to download the build artifact from a previous runtime_build_and_test.yml run
-      actions: read
     steps:
       - uses: actions/checkout@v4
       - uses: actions/setup-node@v4
@@ -34,15 +29,13 @@ jobs:
         uses: actions/cache@v4
         id: node_modules
         with:
-          path: |
-            **/node_modules
-          key: runtime-release-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock', 'scripts/release/yarn.lock') }}
+          path: "**/node_modules"
+          key: runtime-release-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock', 'scripts/release/yarn.lock') }}
       - name: Ensure clean build directory
         run: rm -rf build
       - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
-      - run: yarn --cwd scripts/release install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
+      - run: yarn install --frozen-lockfile
+        working-directory: scripts/release
       - name: Download react-devtools artifacts for base revision
         run: |
           git fetch origin main
@@ -54,7 +47,6 @@ jobs:
         with:
           name: build
           path: build
-          if-no-files-found: error
 
   build_devtools_and_process_artifacts:
     name: Build DevTools and process artifacts
@@ -71,13 +63,11 @@ jobs:
         uses: actions/cache@v4
         id: node_modules
         with:
-          path: |
-            **/node_modules
-          key: runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
+          path: "**/node_modules"
+          key: runtime-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
       - name: Ensure clean build directory
         run: rm -rf build
       - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
       - name: Restore archived build
         uses: actions/download-artifact@v4
         with:
@@ -93,20 +83,17 @@ jobs:
         with:
           name: react-devtools
           path: build/devtools.tgz
-          if-no-files-found: error
       # Simplifies getting the extension for local testing
       - name: Archive chrome extension
         uses: actions/upload-artifact@v4
         with:
           name: react-devtools-chrome-extension
           path: build/devtools/chrome-extension.zip
-          if-no-files-found: error
       - name: Archive firefox extension
         uses: actions/upload-artifact@v4
         with:
           name: react-devtools-firefox-extension
           path: build/devtools/firefox-extension.zip
-          if-no-files-found: error
 
   run_devtools_tests_for_versions:
     name: Run DevTools tests for versions
@@ -133,11 +120,9 @@ jobs:
         uses: actions/cache@v4
         id: node_modules
         with:
-          path: |
-            **/node_modules
-          key: runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
+          path: "**/node_modules"
+          key: runtime-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
       - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
       - name: Restore all archived build artifacts
         uses: actions/download-artifact@v4
       - name: Display structure of build
@@ -169,28 +154,17 @@ jobs:
         uses: actions/cache@v4
         id: node_modules
         with:
-          path: |
-            **/node_modules
-          key: runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
+          path: "**/node_modules"
+          key: runtime-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
       - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
       - name: Restore all archived build artifacts
         uses: actions/download-artifact@v4
       - name: Display structure of build
         run: ls -R build
-      - name: Check Playwright version
-        id: playwright_version
-        run: echo "playwright_version=$(npm ls @playwright/test | grep @playwright | sed 's/.*@//' | head -1)" >> "$GITHUB_OUTPUT"
-      - name: Cache Playwright Browsers for version ${{ steps.playwright_version.outputs.playwright_version }}
-        id: cache_playwright_browsers
-        uses: actions/cache@v4
-        with:
-          path: ~/.cache/ms-playwright
-          key: playwright-browsers-v6-${{ runner.arch }}-${{ runner.os }}-${{ steps.playwright_version.outputs.playwright_version }}
-      - run: npx playwright install --with-deps
-        if: steps.cache_playwright_browsers.outputs.cache-hit != 'true'
-      - run: npx playwright install-deps
-        if: steps.cache_playwright_browsers.outputs.cache-hit == 'true'
+      - name: Playwright install deps
+        run: |
+          npx playwright install
+          sudo npx playwright install-deps
       - run: ./scripts/ci/download_devtools_regression_build.js ${{ matrix.version }}
       - run: ls -R build-regression
       - run: ./scripts/ci/run_devtools_e2e_tests.js ${{ matrix.version }}
@@ -202,4 +176,3 @@ jobs:
         with:
           name: screenshots
           path: ./tmp/screenshots
-          if-no-files-found: warn

.github/workflows/runtime_build_and_test.yml

@@ -6,14 +6,6 @@ on:
   pull_request:
     paths-ignore:
       - compiler/**
-  workflow_dispatch:
-    inputs:
-      commit_sha:
-        required: false
-        type: string
-        default: ''
-
-permissions: {}
 
 concurrency:
   group: ${{ github.workflow }}-${{ github.ref_name }}-${{ github.event.pull_request.number || github.run_id }}
@@ -25,95 +17,6 @@ env:
   SEGMENT_DOWNLOAD_TIMEOUT_MINS: 1
 
 jobs:
-  # ----- NODE_MODULES CACHE -----
-  # Centralize the node_modules cache so it is saved once and each subsequent job only needs to
-  # restore the cache. Prevents race conditions where multiple workflows try to write to the cache.
-  runtime_node_modules_cache:
-    name: Cache Runtime node_modules
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v4
-        with:
-          ref: ${{ github.event.inputs.commit_sha != '' && github.event.inputs.commit_sha || github.event.pull_request.head.sha || github.sha }}
-      - name: Check cache hit
-        uses: actions/cache/restore@v4
-        id: node_modules
-        with:
-          path: |
-            **/node_modules
-          key: runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
-          lookup-only: true
-      - uses: actions/setup-node@v4
-        if: steps.node_modules.outputs.cache-hit != 'true'
-        with:
-          node-version-file: '.nvmrc'
-          cache: yarn
-          cache-dependency-path: yarn.lock
-      - name: Warm with old cache
-        if: steps.node_modules.outputs.cache-hit != 'true'
-        uses: actions/cache/restore@v4
-        with:
-          path: |
-            **/node_modules
-          key: runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
-          restore-keys: |
-            runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-
-            runtime-node_modules-v6-
-      - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
-      - name: Save cache
-        if: steps.node_modules.outputs.cache-hit != 'true'
-        uses: actions/cache/save@v4
-        with:
-          path: |
-            **/node_modules
-          key: runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
-
-  runtime_compiler_node_modules_cache:
-    name: Cache Runtime, Compiler node_modules
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v4
-        with:
-          ref: ${{ github.event.inputs.commit_sha != '' && github.event.inputs.commit_sha || github.event.pull_request.head.sha || github.sha }}
-      - name: Check cache hit
-        uses: actions/cache/restore@v4
-        id: node_modules
-        with:
-          path: |
-            **/node_modules
-          key: runtime-and-compiler-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock', 'compiler/yarn.lock') }}
-          lookup-only: true
-      - uses: actions/setup-node@v4
-        if: steps.node_modules.outputs.cache-hit != 'true'
-        with:
-          node-version-file: '.nvmrc'
-          cache: yarn
-          cache-dependency-path: |
-            yarn.lock
-            compiler/yarn.lock
-      - name: Warm with old cache
-        if: steps.node_modules.outputs.cache-hit != 'true'
-        uses: actions/cache/restore@v4
-        with:
-          path: |
-            **/node_modules
-          key: runtime-and-compiler-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock', 'compiler/yarn.lock') }}
-          restore-keys: |
-            runtime-and-compiler-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-
-            runtime-and-compiler-node_modules-v6-
-      - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
-      - run: yarn --cwd compiler install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
-      - name: Save cache
-        if: steps.node_modules.outputs.cache-hit != 'true'
-        uses: actions/cache/save@v4
-        with:
-          path: |
-            **/node_modules
-          key: runtime-and-compiler-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock', 'compiler/yarn.lock') }}
-
   # ----- FLOW -----
   discover_flow_inline_configs:
     name: Discover flow inline configs
@@ -123,7 +26,7 @@ jobs:
     steps:
       - uses: actions/checkout@v4
         with:
-          ref: ${{ github.event.inputs.commit_sha != '' && github.event.inputs.commit_sha || github.event.pull_request.head.sha || github.sha }}
+          ref: ${{ github.event.pull_request.head.sha || github.sha }}
       - uses: actions/github-script@v7
         id: set-matrix
         with:
@@ -133,7 +36,7 @@ jobs:
 
   flow:
     name: Flow check ${{ matrix.flow_inline_config_shortname }}
-    needs: [discover_flow_inline_configs, runtime_node_modules_cache]
+    needs: discover_flow_inline_configs
     runs-on: ubuntu-latest
     strategy:
       fail-fast: false
@@ -142,56 +45,45 @@ jobs:
     steps:
       - uses: actions/checkout@v4
         with:
-          ref: ${{ github.event.inputs.commit_sha != '' && github.event.inputs.commit_sha || github.event.pull_request.head.sha || github.sha }}
+          ref: ${{ github.event.pull_request.head.sha || github.sha }}
       - uses: actions/setup-node@v4
         with:
           node-version-file: '.nvmrc'
           cache: yarn
           cache-dependency-path: yarn.lock
       - name: Restore cached node_modules
-        uses: actions/cache/restore@v4
+        uses: actions/cache@v4
         id: node_modules
         with:
-          path: |
-            **/node_modules
-          key: runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
-          restore-keys: |
-            runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-
-            runtime-node_modules-v6-
+          path: "**/node_modules"
+          key: runtime-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
       - name: Ensure clean build directory
         run: rm -rf build
       - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
       - run: node ./scripts/tasks/flow-ci ${{ matrix.flow_inline_config_shortname }}
 
   # ----- FIZZ -----
   check_generated_fizz_runtime:
     name: Confirm generated inline Fizz runtime is up to date
-    needs: [runtime_node_modules_cache]
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
         with:
-          ref: ${{ github.event.inputs.commit_sha != '' && github.event.inputs.commit_sha || github.event.pull_request.head.sha || github.sha }}
+          ref: ${{ github.event.pull_request.head.sha || github.sha }}
       - uses: actions/setup-node@v4
         with:
           node-version-file: '.nvmrc'
           cache: yarn
           cache-dependency-path: yarn.lock
       - name: Restore cached node_modules
-        uses: actions/cache/restore@v4
+        uses: actions/cache@v4
         id: node_modules
         with:
-          path: |
-            **/node_modules
-          key: runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
-          restore-keys: |
-            runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-
-            runtime-node_modules-v6-
+          path: "**/node_modules"
+          key: runtime-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
       - name: Ensure clean build directory
         run: rm -rf build
       - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
       - run: |
           yarn generate-inline-fizz-runtime
           git diff --quiet || (echo "There was a change to the Fizz runtime. Run `yarn generate-inline-fizz-runtime` and check in the result." && false)
@@ -199,34 +91,30 @@ jobs:
   # ----- FEATURE FLAGS -----
   flags:
     name: Check flags
-    needs: [runtime_node_modules_cache]
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
         with:
-          ref: ${{ github.event.inputs.commit_sha != '' && github.event.inputs.commit_sha || github.event.pull_request.head.sha || github.sha }}
+          ref: ${{ github.event.pull_request.head.sha || github.sha }}
       - uses: actions/setup-node@v4
         with:
           node-version-file: '.nvmrc'
           cache: yarn
           cache-dependency-path: yarn.lock
       - name: Restore cached node_modules
-        uses: actions/cache/restore@v4
+        uses: actions/cache@v4
         id: node_modules
         with:
-          path: |
-            **/node_modules
-          key: runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
+          path: "**/node_modules"
+          key: runtime-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
       - name: Ensure clean build directory
         run: rm -rf build
       - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
       - run: yarn flags
 
   # ----- TESTS -----
   test:
     name: yarn test ${{ matrix.params }} (Shard ${{ matrix.shard }})
-    needs: [runtime_compiler_node_modules_cache]
     runs-on: ubuntu-latest
     strategy:
       fail-fast: false
@@ -260,106 +148,56 @@ jobs:
     steps:
       - uses: actions/checkout@v4
         with:
-          ref: ${{ github.event.inputs.commit_sha != '' && github.event.inputs.commit_sha || github.event.pull_request.head.sha || github.sha }}
+          ref: ${{ github.event.pull_request.head.sha || github.sha }}
       - uses: actions/setup-node@v4
         with:
           node-version-file: '.nvmrc'
           cache: yarn
-          cache-dependency-path: |
-            yarn.lock
-            compiler/yarn.lock
-      - name: Restore cached node_modules
-        uses: actions/cache/restore@v4
-        id: node_modules
-        with:
-          path: |
-            **/node_modules
-          key: runtime-and-compiler-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock', 'compiler/yarn.lock') }}
-          restore-keys: |
-            runtime-and-compiler-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-
-            runtime-and-compiler-node_modules-v6-
-      - name: Ensure clean build directory
-        run: rm -rf build
-      - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
-      - run: yarn --cwd compiler install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
-      - run: yarn test ${{ matrix.params }} --ci --shard=${{ matrix.shard }}
-
-  # Hardcoded to improve parallelism
-  test-linter:
-    name: Test eslint-plugin-react-hooks
-    needs: [runtime_compiler_node_modules_cache]
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v4
-      - uses: actions/setup-node@v4
-        with:
-          node-version-file: '.nvmrc'
-          cache: yarn
-          cache-dependency-path:  |
-            yarn.lock
-            compiler/yarn.lock
+          cache-dependency-path: yarn.lock
       - name: Restore cached node_modules
         uses: actions/cache@v4
         id: node_modules
         with:
-          path: |
-            **/node_modules
-          key: runtime-and-compiler-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock', 'compiler/yarn.lock') }}
-      - name: Install runtime dependencies
-        run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
-      - name: Install compiler dependencies
-        run: yarn install --frozen-lockfile
-        working-directory: compiler
-        if: steps.node_modules.outputs.cache-hit != 'true'
-      - run: ./scripts/react-compiler/build-compiler.sh && ./scripts/react-compiler/link-compiler.sh
-      - run: yarn workspace eslint-plugin-react-hooks test
-        
+          path: "**/node_modules"
+          key: runtime-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
+      - name: Ensure clean build directory
+        run: rm -rf build
+      - run: yarn install --frozen-lockfile
+      - run: yarn test ${{ matrix.params }} --ci --shard=${{ matrix.shard }}
+
   # ----- BUILD -----
   build_and_lint:
     name: yarn build and lint
-    needs: [runtime_compiler_node_modules_cache]
     runs-on: ubuntu-latest
     strategy:
       fail-fast: false
       matrix:
         # yml is dumb. update the --total arg to yarn build if you change the number of workers
-        worker_id: [0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24]
+        worker_id: [0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19]
         release_channel: [stable, experimental]
     steps:
       - uses: actions/checkout@v4
         with:
-          ref: ${{ github.event.inputs.commit_sha != '' && github.event.inputs.commit_sha || github.event.pull_request.head.sha || github.sha }}
+          ref: ${{ github.event.pull_request.head.sha || github.sha }}
       - uses: actions/setup-node@v4
         with:
           node-version-file: '.nvmrc'
           cache: yarn
-          cache-dependency-path: |
-            yarn.lock
-            compiler/yarn.lock
+          cache-dependency-path: yarn.lock
       - uses: actions/setup-java@v4
         with:
           distribution: temurin
           java-version: 11.0.22
       - name: Restore cached node_modules
-        uses: actions/cache/restore@v4
+        uses: actions/cache@v4
         id: node_modules
         with:
-          path: |
-            **/node_modules
-          key: runtime-and-compiler-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock', 'compiler/yarn.lock') }}
-          restore-keys: |
-            runtime-and-compiler-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-
-            runtime-and-compiler-node_modules-v6-
+          path: "**/node_modules"
+          key: runtime-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
       - name: Ensure clean build directory
         run: rm -rf build
       - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
-      - run: yarn --cwd compiler install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
-      - run: yarn build --index=${{ matrix.worker_id }} --total=25 --r=${{ matrix.release_channel }} --ci
+      - run: yarn build --index=${{ matrix.worker_id }} --total=20 --r=${{ matrix.release_channel }} --ci
         env:
           CI: github
           RELEASE_CHANNEL: ${{ matrix.release_channel }}
@@ -373,11 +211,10 @@ jobs:
         with:
           name: _build_${{ matrix.worker_id }}_${{ matrix.release_channel }}
           path: build
-          if-no-files-found: error
 
   test_build:
     name: yarn test-build
-    needs: [build_and_lint, runtime_compiler_node_modules_cache]
+    needs: build_and_lint
     strategy:
       fail-fast: false
       matrix:
@@ -412,44 +249,28 @@ jobs:
           # TODO: Test more persistent configurations?
         ]
         shard:
-          - 1/10
-          - 2/10
-          - 3/10
-          - 4/10
-          - 5/10
-          - 6/10
-          - 7/10
-          - 8/10
-          - 9/10
-          - 10/10
+          - 1/3
+          - 2/3
+          - 3/3
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
         with:
-          ref: ${{ github.event.inputs.commit_sha != '' && github.event.inputs.commit_sha || github.event.pull_request.head.sha || github.sha }}
+          ref: ${{ github.event.pull_request.head.sha || github.sha }}
       - uses: actions/setup-node@v4
         with:
           node-version-file: '.nvmrc'
           cache: yarn
-          cache-dependency-path: |
-            yarn.lock
-            compiler/yarn.lock
+          cache-dependency-path: yarn.lock
       - name: Restore cached node_modules
-        uses: actions/cache/restore@v4
+        uses: actions/cache@v4
         id: node_modules
         with:
-          path: |
-            **/node_modules
-          key: runtime-and-compiler-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock', 'compiler/yarn.lock') }}
-          restore-keys: |
-            runtime-and-compiler-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-
-            runtime-and-compiler-node_modules-v6-
+          path: "**/node_modules"
+          key: runtime-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
       - name: Ensure clean build directory
         run: rm -rf build
       - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
-      - run: yarn --cwd compiler install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
       - name: Restore archived build
         uses: actions/download-artifact@v4
         with:
@@ -462,35 +283,26 @@ jobs:
 
   process_artifacts_combined:
     name: Process artifacts combined
-    needs: [build_and_lint, runtime_node_modules_cache]
-    permissions:
-      # https://github.com/actions/attest-build-provenance
-      id-token: write
-      attestations: write
+    needs: build_and_lint
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
         with:
-          ref: ${{ github.event.inputs.commit_sha != '' && github.event.inputs.commit_sha || github.event.pull_request.head.sha || github.sha }}
+          ref: ${{ github.event.pull_request.head.sha || github.sha }}
       - uses: actions/setup-node@v4
         with:
           node-version-file: '.nvmrc'
           cache: yarn
           cache-dependency-path: yarn.lock
       - name: Restore cached node_modules
-        uses: actions/cache/restore@v4
+        uses: actions/cache@v4
         id: node_modules
         with:
-          path: |
-            **/node_modules
-          key: runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
-          restore-keys: |
-            runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-
-            runtime-node_modules-v6-
+          path: "**/node_modules"
+          key: runtime-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
       - name: Ensure clean build directory
         run: rm -rf build
       - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
       - name: Restore archived build
         uses: actions/download-artifact@v4
         with:
@@ -499,7 +311,7 @@ jobs:
           merge-multiple: true
       - name: Display structure of build
         run: ls -R build
-      - run: echo ${{ github.event.inputs.commit_sha != '' && github.event.inputs.commit_sha || github.event.pull_request.head.sha || github.sha }} >> build/COMMIT_SHA
+      - run: echo ${{ github.sha }} >> build/COMMIT_SHA
       - name: Scrape warning messages
         run: |
           mkdir -p ./build/__test_utils__
@@ -509,53 +321,35 @@ jobs:
         # TODO: Migrate scripts to use `build` directory instead of `build2`
       - run: cp ./build.tgz ./build2.tgz
       - name: Archive build artifacts
-        id: upload_artifacts_combined
         uses: actions/upload-artifact@v4
         with:
           name: artifacts_combined
           path: |
             ./build.tgz
             ./build2.tgz
-          if-no-files-found: error
-      - uses: actions/attest-build-provenance@v2
-        # We don't verify builds generated from pull requests not originating from facebook/react.
-        # However, if the PR lands, the run on `main` will generate the attestation which can then
-        # be used to download a build via scripts/release/download-experimental-build.js.
-        #
-        # Note that this means that scripts/release/download-experimental-build.js must be run with
-        # --no-verify when downloading a build from a fork.
-        if: github.event_name == 'push' && github.ref_name == 'main' || github.event.pull_request.head.repo.full_name == github.repository
-        with:
-          subject-name: artifacts_combined.zip
-          subject-digest: sha256:${{ steps.upload_artifacts_combined.outputs.artifact-digest }}
 
   check_error_codes:
     name: Search build artifacts for unminified errors
-    needs: [build_and_lint, runtime_node_modules_cache]
+    needs: build_and_lint
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
         with:
-          ref: ${{ github.event.inputs.commit_sha != '' && github.event.inputs.commit_sha || github.event.pull_request.head.sha || github.sha }}
+          ref: ${{ github.event.pull_request.head.sha || github.sha }}
       - uses: actions/setup-node@v4
         with:
           node-version-file: '.nvmrc'
           cache: yarn
           cache-dependency-path: yarn.lock
       - name: Restore cached node_modules
-        uses: actions/cache/restore@v4
+        uses: actions/cache@v4
         id: node_modules
         with:
-          path: |
-            **/node_modules
-          key: runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
-          restore-keys: |
-            runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-
-            runtime-node_modules-v6-
+          path: "**/node_modules"
+          key: runtime-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
       - name: Ensure clean build directory
         run: rm -rf build
       - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
       - name: Restore archived build
         uses: actions/download-artifact@v4
         with:
@@ -571,31 +365,26 @@ jobs:
 
   check_release_dependencies:
     name: Check release dependencies
-    needs: [build_and_lint, runtime_node_modules_cache]
+    needs: build_and_lint
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
         with:
-          ref: ${{ github.event.inputs.commit_sha != '' && github.event.inputs.commit_sha || github.event.pull_request.head.sha || github.sha }}
+          ref: ${{ github.event.pull_request.head.sha || github.sha }}
       - uses: actions/setup-node@v4
         with:
           node-version-file: '.nvmrc'
           cache: yarn
           cache-dependency-path: yarn.lock
       - name: Restore cached node_modules
-        uses: actions/cache/restore@v4
+        uses: actions/cache@v4
         id: node_modules
         with:
-          path: |
-            **/node_modules
-          key: runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
-          restore-keys: |
-            runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-
-            runtime-node_modules-v6-
+          path: "**/node_modules"
+          key: runtime-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
       - name: Ensure clean build directory
         run: rm -rf build
       - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
       - name: Restore archived build
         uses: actions/download-artifact@v4
         with:
@@ -613,23 +402,22 @@ jobs:
     steps:
       - uses: actions/checkout@v4
         with:
-          ref: ${{ github.event.inputs.commit_sha != '' && github.event.inputs.commit_sha || github.event.pull_request.head.sha || github.sha }}
+          ref: ${{ github.event.pull_request.head.sha || github.sha }}
       - uses: actions/setup-node@v4
         with:
           node-version-file: '.nvmrc'
           cache: yarn
           cache-dependency-path: yarn.lock
       - name: Restore cached node_modules
-        uses: actions/cache@v4 # note: this does not reuse centralized cache since it has unique cache key
+        uses: actions/cache@v4
         id: node_modules
         with:
-          path: |
-            **/node_modules
-          key: fixtures_dom-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock', 'fixtures/dom/yarn.lock') }}
+          path: "**/node_modules"
+          key: fixtures_dom-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
       - name: Ensure clean build directory
         run: rm -rf build
-      - run: yarn --cwd fixtures/dom install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
+      - run: yarn install --frozen-lockfile
+        working-directory: fixtures/dom
       - name: Restore archived build
         uses: actions/download-artifact@v4
         with:
@@ -654,7 +442,7 @@ jobs:
     steps:
       - uses: actions/checkout@v4
         with:
-          ref: ${{ github.event.inputs.commit_sha != '' && github.event.inputs.commit_sha || github.event.pull_request.head.sha || github.sha }}
+          ref: ${{ github.event.pull_request.head.sha || github.sha }}
       - uses: actions/setup-node@v4
         with:
           node-version-file: '.nvmrc'
@@ -664,31 +452,14 @@ jobs:
       # That means dependencies of the built packages are not installed.
       # We need to install dependencies of the workroot to fulfill all dependency constraints
       - name: Restore cached node_modules
-        uses: actions/cache@v4 # note: this does not reuse centralized cache since it has unique cache key
+        uses: actions/cache@v4
         id: node_modules
         with:
-          path: |
-            **/node_modules
-          key: fixtures_flight-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock', 'fixtures/flight/yarn.lock') }}
+          path: "**/node_modules"
+          key: fixtures_flight-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
       - name: Ensure clean build directory
         run: rm -rf build
       - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
-      - run: yarn --cwd fixtures/flight install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
-      - name: Check Playwright version
-        id: playwright_version
-        run: echo "playwright_version=$(npm ls @playwright/test | grep @playwright | sed 's/.*@//' | head -1)" >> "$GITHUB_OUTPUT"
-      - name: Cache Playwright Browsers for version ${{ steps.playwright_version.outputs.playwright_version }}
-        id: cache_playwright_browsers
-        uses: actions/cache@v4
-        with:
-          path: ~/.cache/ms-playwright
-          key: playwright-browsers-v6-${{ runner.arch }}-${{ runner.os }}-${{ steps.playwright_version.outputs.playwright_version }}
-      - name: Playwright install deps
-        if: steps.cache_playwright_browsers.outputs.cache-hit != 'true'
-        working-directory: fixtures/flight
-        run: npx playwright install --with-deps chromium
       - name: Restore archived build
         uses: actions/download-artifact@v4
         with:
@@ -697,6 +468,16 @@ jobs:
           merge-multiple: true
       - name: Display structure of build
         run: ls -R build
+      - name: Install fixture dependencies
+        working-directory: fixtures/flight
+        run: |
+          yarn install --frozen-lockfile --cache-folder ~/.cache/yarn
+          if [ $? -ne 0 ]; then
+            yarn install --frozen-lockfile --cache-folder ~/.cache/yarn
+          fi
+      - name: Playwright install deps
+        working-directory: fixtures/flight
+        run: npx playwright install --with-deps chromium
       - name: Run tests
         working-directory: fixtures/flight
         run: yarn test
@@ -708,18 +489,16 @@ jobs:
         with:
           name: flight-playwright-report
           path: fixtures/flight/playwright-report
-          if-no-files-found: warn
       - name: Archive Flight fixture artifacts
         uses: actions/upload-artifact@v4
         with:
           name: flight-test-results
           path: fixtures/flight/test-results
-          if-no-files-found: ignore
 
   # ----- DEVTOOLS -----
   build_devtools_and_process_artifacts:
     name: Build DevTools and process artifacts
-    needs: [build_and_lint, runtime_node_modules_cache]
+    needs: build_and_lint
     runs-on: ubuntu-latest
     strategy:
       fail-fast: false
@@ -728,26 +507,21 @@ jobs:
     steps:
       - uses: actions/checkout@v4
         with:
-          ref: ${{ github.event.inputs.commit_sha != '' && github.event.inputs.commit_sha || github.event.pull_request.head.sha || github.sha }}
+          ref: ${{ github.event.pull_request.head.sha || github.sha }}
       - uses: actions/setup-node@v4
         with:
           node-version-file: '.nvmrc'
           cache: yarn
           cache-dependency-path: yarn.lock
       - name: Restore cached node_modules
-        uses: actions/cache/restore@v4
+        uses: actions/cache@v4
         id: node_modules
         with:
-          path: |
-            **/node_modules
-          key: runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
-          restore-keys: |
-            runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-
-            runtime-node_modules-v6-
+          path: "**/node_modules"
+          key: runtime-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
       - name: Ensure clean build directory
         run: rm -rf build
       - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
       - name: Restore archived build
         uses: actions/download-artifact@v4
         with:
@@ -765,7 +539,6 @@ jobs:
         with:
           name: react-devtools-${{ matrix.browser }}-extension
           path: build/devtools/${{ matrix.browser }}-extension.zip
-          if-no-files-found: error
 
   merge_devtools_artifacts:
     name: Merge DevTools artifacts
@@ -780,31 +553,26 @@ jobs:
 
   run_devtools_e2e_tests:
     name: Run DevTools e2e tests
-    needs: [build_and_lint, runtime_node_modules_cache]
+    needs: build_and_lint
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
         with:
-          ref: ${{ github.event.inputs.commit_sha != '' && github.event.inputs.commit_sha || github.event.pull_request.head.sha || github.sha }}
+          ref: ${{ github.event.pull_request.head.sha || github.sha }}
       - uses: actions/setup-node@v4
         with:
           node-version-file: '.nvmrc'
           cache: yarn
           cache-dependency-path: yarn.lock
       - name: Restore cached node_modules
-        uses: actions/cache/restore@v4
+        uses: actions/cache@v4
         id: node_modules
         with:
-          path: |
-            **/node_modules
-          key: runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
-          restore-keys: |
-            runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-
-            runtime-node_modules-v6-
+          path: "**/node_modules"
+          key: runtime-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
       - name: Ensure clean build directory
         run: rm -rf build
       - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
       - name: Restore archived build
         uses: actions/download-artifact@v4
         with:
@@ -823,50 +591,41 @@ jobs:
     if: ${{ github.event_name == 'pull_request' && github.ref_name != 'main' && github.event.pull_request.base.ref == 'main' }}
     name: Run sizebot
     needs: [build_and_lint]
-    permissions:
-      # We use github.token to download the build artifact from a previous runtime_build_and_test.yml run
-      actions: read
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
         with:
-          ref: ${{ github.event.inputs.commit_sha != '' && github.event.inputs.commit_sha || github.event.pull_request.head.sha || github.sha }}
+          ref: ${{ github.event.pull_request.head.sha || github.sha }}
       - uses: actions/setup-node@v4
         with:
           node-version-file: '.nvmrc'
           cache: yarn
           cache-dependency-path: yarn.lock
       - name: Restore cached node_modules
-        uses: actions/cache@v4 # note: this does not reuse centralized cache since it has unique cache key
+        uses: actions/cache@v4
         id: node_modules
         with:
-          path: |
-            **/node_modules
-          key: runtime-release-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock', 'scripts/release/yarn.lock') }}
+          path: "**/node_modules"
+          key: runtime-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
       - name: Ensure clean build directory
         run: rm -rf build
       - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
-      - run: yarn --cwd scripts/release install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
+        working-directory: scripts/release
       - name: Download artifacts for base revision
-        # The build could have been generated from a fork, so we must download the build without
-        # any verification. This is safe since we only use this for sizebot calculation and the
-        # unverified artifact is not used. Additionally this workflow runs in the pull_request
-        # trigger so only restricted permissions are available.
         run: |
-          GH_TOKEN=${{ github.token }} scripts/release/download-experimental-build.js --commit=$(git rev-parse ${{ github.event.pull_request.base.sha }}) ${{ (github.event.pull_request.head.repo.full_name != github.repository && '--noVerify') || ''}}
+          GH_TOKEN=${{ github.token }} scripts/release/download-experimental-build.js --commit=$(git rev-parse ${{ github.event.pull_request.base.sha }})
           mv ./build ./base-build
+      # TODO: The `download-experimental-build` script copies the npm
+      # packages into the `node_modules` directory. This is a historical
+      # quirk of how the release script works. Let's pretend they
+      # don't exist.
       - name: Delete extraneous files
-        # TODO: The `download-experimental-build` script copies the npm
-        # packages into the `node_modules` directory. This is a historical
-        # quirk of how the release script works. Let's pretend they
-        # don't exist.
         run: rm -rf ./base-build/node_modules
       - name: Display structure of base-build from origin/main
         run: ls -R base-build
       - name: Ensure clean build directory
         run: rm -rf build
+      - run: yarn install --frozen-lockfile
       - name: Restore archived build for PR
         uses: actions/download-artifact@v4
         with:
@@ -879,11 +638,10 @@ jobs:
           node ./scripts/print-warnings/print-warnings.js > build/__test_utils__/ReactAllWarnings.js
       - name: Display structure of build for PR
         run: ls -R build
-      - run: echo ${{ github.event.inputs.commit_sha != '' && github.event.inputs.commit_sha || github.event.pull_request.head.sha || github.sha }} >> build/COMMIT_SHA
+      - run: echo ${{ github.sha }} >> build/COMMIT_SHA
       - run: node ./scripts/tasks/danger
       - name: Archive sizebot results
         uses: actions/upload-artifact@v4
         with:
           name: sizebot-message
           path: sizebot-message.md
-          if-no-files-found: ignore

.github/workflows/runtime_commit_artifacts.yml

@@ -16,13 +16,6 @@ on:
         required: true
         default: false
         type: boolean
-      dry_run:
-        description: Perform a dry run (run everything except push)
-        required: true
-        default: false
-        type: boolean
-
-permissions: {}
 
 env:
   TZ: /usr/share/zoneinfo/America/Los_Angeles
@@ -32,40 +25,6 @@ env:
 jobs:
   download_artifacts:
     runs-on: ubuntu-latest
-    permissions:
-      # We use github.token to download the build artifact from a previous runtime_build_and_test.yml run
-      actions: read
-    steps:
-      - uses: actions/checkout@v4
-      - name: Restore cached node_modules
-        uses: actions/cache@v4
-        id: node_modules
-        with:
-          path: |
-            **/node_modules
-          key: runtime-release-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock', 'scripts/release/yarn.lock') }}
-      - name: Ensure clean build directory
-        run: rm -rf build
-      - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
-      - run: yarn --cwd scripts/release install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
-      - name: Download artifacts for base revision
-        run: |
-          GH_TOKEN=${{ github.token }} scripts/release/download-experimental-build.js --commit=${{ inputs.commit_sha || github.event.workflow_run.head_sha || github.sha }}
-      - name: Display structure of build
-        run: ls -R build
-      - name: Archive build
-        uses: actions/upload-artifact@v4
-        with:
-          name: build
-          path: build/
-          if-no-files-found: error
-
-
-  process_artifacts:
-    runs-on: ubuntu-latest
-    needs: [download_artifacts]
     outputs:
       www_branch_count: ${{ steps.check_branches.outputs.www_branch_count }}
       fbsource_branch_count: ${{ steps.check_branches.outputs.fbsource_branch_count }}
@@ -105,11 +64,27 @@ jobs:
         run: |
           echo "www_branch_count=$(git ls-remote --heads origin "refs/heads/meta-www" | wc -l)" >> "$GITHUB_OUTPUT"
           echo "fbsource_branch_count=$(git ls-remote --heads origin "refs/heads/meta-fbsource" | wc -l)" >> "$GITHUB_OUTPUT"
-      - name: Restore downloaded build
-        uses: actions/download-artifact@v4
+      - uses: actions/setup-node@v4
         with:
-          name: build
-          path: build
+          node-version-file: '.nvmrc'
+          cache: yarn
+          cache-dependency-path: yarn.lock
+      - name: Restore cached node_modules
+        uses: actions/cache@v4
+        id: node_modules
+        with:
+          path: "**/node_modules"
+          key: runtime-release-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock', 'scripts/release/yarn.lock') }}
+      - name: Ensure clean build directory
+        run: rm -rf build
+      - run: yarn install --frozen-lockfile
+        name: yarn install (react)
+      - run: yarn install --frozen-lockfile
+        name: yarn install (scripts/release)
+        working-directory: scripts/release
+      - name: Download artifacts for base revision
+        run: |
+          GH_TOKEN=${{ github.token }} scripts/release/download-experimental-build.js --commit=${{ inputs.commit_sha || github.event.workflow_run.head_sha || github.sha }}
       - name: Display structure of build
         run: ls -R build
       - name: Strip @license from eslint plugin and react-refresh
@@ -132,10 +107,9 @@ jobs:
           mkdir ./compiled/facebook-www/__test_utils__
           mv build/__test_utils__/ReactAllWarnings.js ./compiled/facebook-www/__test_utils__/ReactAllWarnings.js
 
-          # Copy eslint-plugin-react-hooks
-          mkdir ./compiled/eslint-plugin-react-hooks
-          cp build/oss-experimental/eslint-plugin-react-hooks/cjs/eslint-plugin-react-hooks.development.js \
-            ./compiled/eslint-plugin-react-hooks/index.js
+          # Move eslint-plugin-react-hooks into facebook-www
+          mv build/oss-experimental/eslint-plugin-react-hooks/cjs/eslint-plugin-react-hooks.development.js \
+            ./compiled/facebook-www/eslint-plugin-react-hooks.js
 
           # Move unstable_server-external-runtime.js into facebook-www
           mv build/oss-experimental/react-dom/unstable_server-external-runtime.js \
@@ -167,21 +141,15 @@ jobs:
           rm $RENDERER_FOLDER/ReactFabric-{dev,prod,profiling}.js
           rm $RENDERER_FOLDER/ReactNativeRenderer-{dev,prod,profiling}.js
 
-          # Copy eslint-plugin-react-hooks
-          # NOTE: This is different from www, here we include the full package
-          #       including package.json to include dependencies in fbsource.
-          mkdir "$BASE_FOLDER/tools"
-          cp -r build/oss-experimental/eslint-plugin-react-hooks "$BASE_FOLDER/tools"
-
           # Move React Native version file
           mv build/facebook-react-native/VERSION_NATIVE_FB ./compiled-rn/VERSION_NATIVE_FB
 
           ls -R ./compiled-rn
       - name: Add REVISION files
         run: |
-          echo ${{ inputs.commit_sha || github.event.workflow_run.head_sha || github.sha }} >> ./compiled/facebook-www/REVISION
+          echo ${{ github.sha }} >> ./compiled/facebook-www/REVISION
           cp ./compiled/facebook-www/REVISION ./compiled/facebook-www/REVISION_TRANSFORMS
-          echo ${{ inputs.commit_sha || github.event.workflow_run.head_sha || github.sha }} >> ./compiled-rn/facebook-fbsource/xplat/js/react-native-github/Libraries/Renderer/REVISION
+          echo ${{ github.sha}} >> ./compiled-rn/facebook-fbsource/xplat/js/react-native-github/Libraries/Renderer/REVISION
       - name: "Get current version string"
         id: get_current_version
         run: |
@@ -198,20 +166,15 @@ jobs:
         with:
           name: compiled
           path: compiled/
-          if-no-files-found: error
       - uses: actions/upload-artifact@v4
         with:
           name: compiled-rn
           path: compiled-rn/
-          if-no-files-found: error
 
   commit_www_artifacts:
-    needs: [download_artifacts, process_artifacts]
-    if: inputs.force == true || (github.ref == 'refs/heads/main' && needs.process_artifacts.outputs.www_branch_count == '0')
+    needs: download_artifacts
+    if: inputs.force == true || (github.ref == 'refs/heads/main' && needs.download_artifacts.outputs.www_branch_count == '0')
     runs-on: ubuntu-latest
-    permissions:
-      # Used to push a commit to builds/facebook-www
-      contents: write
     steps:
       - uses: actions/checkout@v4
         with:
@@ -223,12 +186,12 @@ jobs:
           name: compiled
           path: compiled/
       - name: Revert version changes
-        if: needs.process_artifacts.outputs.last_version_classic != '' && needs.process_artifacts.outputs.last_version_modern != ''
+        if: needs.download_artifacts.outputs.last_version_classic != '' && needs.download_artifacts.outputs.last_version_modern != ''
         env:
-          CURRENT_VERSION_CLASSIC: ${{ needs.process_artifacts.outputs.current_version_classic }}
-          CURRENT_VERSION_MODERN: ${{ needs.process_artifacts.outputs.current_version_modern }}
-          LAST_VERSION_CLASSIC: ${{ needs.process_artifacts.outputs.last_version_classic }}
-          LAST_VERSION_MODERN: ${{ needs.process_artifacts.outputs.last_version_modern }}
+          CURRENT_VERSION_CLASSIC: ${{ needs.download_artifacts.outputs.current_version_classic }}
+          CURRENT_VERSION_MODERN: ${{ needs.download_artifacts.outputs.current_version_modern }}
+          LAST_VERSION_CLASSIC: ${{ needs.download_artifacts.outputs.last_version_classic }}
+          LAST_VERSION_MODERN: ${{ needs.download_artifacts.outputs.last_version_modern }}
         run: |
           echo "Reverting $CURRENT_VERSION_CLASSIC to $LAST_VERSION_CLASSIC"
           grep -rl "$CURRENT_VERSION_CLASSIC" ./compiled || echo "No files found with $CURRENT_VERSION_CLASSIC"
@@ -258,12 +221,12 @@ jobs:
             echo "should_commit=false" >> "$GITHUB_OUTPUT"
           fi
       - name: Re-apply version changes
-        if: inputs.force == true || (steps.check_should_commit.outputs.should_commit == 'true' && needs.process_artifacts.outputs.last_version_classic != '' && needs.process_artifacts.outputs.last_version_modern != '')
+        if: inputs.force == true || (steps.check_should_commit.outputs.should_commit == 'true' && needs.download_artifacts.outputs.last_version_classic != '' && needs.download_artifacts.outputs.last_version_modern != '')
         env:
-          CURRENT_VERSION_CLASSIC: ${{ needs.process_artifacts.outputs.current_version_classic }}
-          CURRENT_VERSION_MODERN: ${{ needs.process_artifacts.outputs.current_version_modern }}
-          LAST_VERSION_CLASSIC: ${{ needs.process_artifacts.outputs.last_version_classic }}
-          LAST_VERSION_MODERN: ${{ needs.process_artifacts.outputs.last_version_modern }}
+          CURRENT_VERSION_CLASSIC: ${{ needs.download_artifacts.outputs.current_version_classic }}
+          CURRENT_VERSION_MODERN: ${{ needs.download_artifacts.outputs.current_version_modern }}
+          LAST_VERSION_CLASSIC: ${{ needs.download_artifacts.outputs.last_version_classic }}
+          LAST_VERSION_MODERN: ${{ needs.download_artifacts.outputs.last_version_modern }}
         run: |
           echo "Re-applying $LAST_VERSION_CLASSIC to $CURRENT_VERSION_CLASSIC"
           grep -rl "$LAST_VERSION_CLASSIC" ./compiled || echo "No files found with $LAST_VERSION_CLASSIC"
@@ -277,31 +240,24 @@ jobs:
       - name: Will commit these changes
         if: inputs.force == true || steps.check_should_commit.outputs.should_commit == 'true'
         run: |
-          git add .
-          git status
-      - name: Check commit message
-        if: inputs.dry_run
-        run: |
-          git fetch origin --quiet
-          git show ${{ inputs.commit_sha || github.event.workflow_run.head_sha || github.sha }} --no-patch --pretty=format:"%B"
+          echo ":"
+          git status -u
       - name: Commit changes to branch
         if: inputs.force == true || steps.check_should_commit.outputs.should_commit == 'true'
-        run: |
-          git config --global user.email "${{ format('{0}@users.noreply.github.com', github.triggering_actor) }}"
-          git config --global user.name "${{ github.triggering_actor }}"
+        uses: stefanzweifel/git-auto-commit-action@v5
+        with:
+          commit_message: |
+            ${{ github.event.workflow_run.head_commit.message || format('Manual build of {0}', github.event.workflow_run.head_sha || github.sha) }}
 
-          git fetch origin --quiet
-          git commit -m "$(git show ${{ inputs.commit_sha || github.event.workflow_run.head_sha || github.sha }} --no-patch --pretty=format:'%B%n%nDiffTrain build for [${{ inputs.commit_sha || github.event.workflow_run.head_sha || github.sha }}](https://github.com/facebook/react/commit/${{ inputs.commit_sha || github.event.workflow_run.head_sha || github.sha}})')" || echo "No changes to commit"
-      - name: Push changes to branch
-        if: inputs.dry_run == false && (inputs.force == true || steps.check_should_commit.outputs.should_commit == 'true')
-        run: git push
+            DiffTrain build for [${{ github.event.workflow_run.head_sha || github.sha }}](https://github.com/facebook/react/commit/${{ github.event.workflow_run.head_sha || github.sha }})
+          branch: builds/facebook-www
+          commit_user_name: ${{ github.triggering_actor }}
+          commit_user_email: ${{ format('{0}@users.noreply.github.com', github.triggering_actor) }}
+          create_branch: true
 
   commit_fbsource_artifacts:
-    needs: [download_artifacts, process_artifacts]
-    permissions:
-      # Used to push a commit to builds/facebook-fbsource
-      contents: write
-    if: inputs.force == true || (github.ref == 'refs/heads/main' && needs.process_artifacts.outputs.fbsource_branch_count == '0')
+    needs: download_artifacts
+    if: inputs.force == true || (github.ref == 'refs/heads/main' && needs.download_artifacts.outputs.fbsource_branch_count == '0')
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
@@ -314,10 +270,10 @@ jobs:
           name: compiled-rn
           path: compiled-rn/
       - name: Revert version changes
-        if: needs.process_artifacts.outputs.last_version_rn != ''
+        if: needs.download_artifacts.outputs.last_version_rn != ''
         env:
-          CURRENT_VERSION: ${{ needs.process_artifacts.outputs.current_version_rn }}
-          LAST_VERSION: ${{ needs.process_artifacts.outputs.last_version_rn }}
+          CURRENT_VERSION: ${{ needs.download_artifacts.outputs.current_version_rn }}
+          LAST_VERSION: ${{ needs.download_artifacts.outputs.last_version_rn }}
         run: |
           echo "Reverting $CURRENT_VERSION to $LAST_VERSION"
           grep -rl "$CURRENT_VERSION" ./compiled-rn || echo "No files found with $CURRENT_VERSION"
@@ -332,10 +288,10 @@ jobs:
           git --no-pager diff -U0 --cached | grep '^[+-]' | head -n 100
           echo "===================="
           # Ignore REVISION or lines removing @generated headers.
-          if git diff --cached ':(exclude)*REVISION' ':(exclude)*/eslint-plugin-react-hooks/package.json' | grep -vE "^(@@|diff|index|\-\-\-|\+\+\+|\- \* @generated SignedSource)" | grep "^[+-]" > /dev/null; then
+          if git diff --cached ':(exclude)*REVISION' | grep -vE "^(@@|diff|index|\-\-\-|\+\+\+|\- \* @generated SignedSource)" | grep "^[+-]" > /dev/null; then
             echo "Changes detected"
             echo "===== Changes ====="
-            git --no-pager diff --cached ':(exclude)*REVISION' ':(exclude)*/eslint-plugin-react-hooks/package.json' | grep -vE "^(@@|diff|index|\-\-\-|\+\+\+|\- \* @generated SignedSource)" | grep "^[+-]" | head -n 50
+            git --no-pager diff --cached ':(exclude)*REVISION' | grep -vE "^(@@|diff|index|\-\-\-|\+\+\+|\- \* @generated SignedSource)" | grep "^[+-]" | head -n 50
             echo "==================="
             echo "should_commit=true" >> "$GITHUB_OUTPUT"
           else
@@ -343,10 +299,10 @@ jobs:
             echo "should_commit=false" >> "$GITHUB_OUTPUT"
           fi
       - name: Re-apply version changes
-        if: inputs.force == true || (steps.check_should_commit.outputs.should_commit == 'true' && needs.process_artifacts.outputs.last_version_rn != '')
+        if: inputs.force == true || (steps.check_should_commit.outputs.should_commit == 'true' && needs.download_artifacts.outputs.last_version_rn != '')
         env:
-          CURRENT_VERSION: ${{ needs.process_artifacts.outputs.current_version_rn }}
-          LAST_VERSION: ${{ needs.process_artifacts.outputs.last_version_rn }}
+          CURRENT_VERSION: ${{ needs.download_artifacts.outputs.current_version_rn }}
+          LAST_VERSION: ${{ needs.download_artifacts.outputs.last_version_rn }}
         run: |
           echo "Re-applying $LAST_VERSION to $CURRENT_VERSION"
           grep -rl "$LAST_VERSION" ./compiled-rn || echo "No files found with $LAST_VERSION"
@@ -453,19 +409,15 @@ jobs:
         run: |
           git add .
           git status
-      - name: Check commit message
-        if: inputs.dry_run
-        run: |
-          git fetch origin --quiet
-          git show ${{ inputs.commit_sha || github.event.workflow_run.head_sha || github.sha }} --no-patch --pretty=format:"%B"
       - name: Commit changes to branch
         if: inputs.force == true || steps.check_should_commit.outputs.should_commit == 'true'
-        run: |
-          git config --global user.email "${{ format('{0}@users.noreply.github.com', github.triggering_actor) }}"
-          git config --global user.name "${{ github.triggering_actor }}"
+        uses: stefanzweifel/git-auto-commit-action@v5
+        with:
+          commit_message: |
+            ${{ github.event.workflow_run.head_commit.message || format('Manual build of {0}', github.event.workflow_run.head_sha || github.sha) }}
 
-          git fetch origin --quiet
-          git commit -m "$(git show ${{ inputs.commit_sha || github.event.workflow_run.head_sha || github.sha }} --no-patch --pretty=format:'%B%n%nDiffTrain build for [${{ inputs.commit_sha || github.event.workflow_run.head_sha || github.sha }}](https://github.com/facebook/react/commit/${{ inputs.commit_sha || github.event.workflow_run.head_sha || github.sha}})')" || echo "No changes to commit"
-      - name: Push changes to branch
-        if: inputs.dry_run == false && (inputs.force == true || steps.check_should_commit.outputs.should_commit == 'true')
-        run: git push
+            DiffTrain build for [${{ github.event.workflow_run.head_sha || github.sha }}](https://github.com/facebook/react/commit/${{ github.event.workflow_run.head_sha || github.sha }})
+          branch: builds/facebook-fbsource
+          commit_user_name: ${{ github.triggering_actor }}
+          commit_user_email: ${{ format('{0}@users.noreply.github.com', github.triggering_actor) }}
+          create_branch: true

.github/workflows/runtime_discord_notify.yml

@@ -7,28 +7,9 @@ on:
       - compiler/**
       - .github/workflows/compiler_**.yml
 
-permissions: {}
-
 jobs:
-  check_access:
-    if: ${{ github.event.pull_request.draft == false }}
-    runs-on: ubuntu-latest
-    outputs:
-      is_member_or_collaborator: ${{ steps.check_is_member_or_collaborator.outputs.is_member_or_collaborator }}
-    steps:
-      - run: echo ${{ github.event.pull_request.author_association }}
-      - name: Check is member or collaborator
-        id: check_is_member_or_collaborator
-        if: ${{ github.event.pull_request.author_association == 'MEMBER' || github.event.pull_request.author_association == 'COLLABORATOR' }}
-        run: echo "is_member_or_collaborator=true" >> "$GITHUB_OUTPUT"
-
   check_maintainer:
-    if: ${{ needs.check_access.outputs.is_member_or_collaborator == 'true' || needs.check_access.outputs.is_member_or_collaborator == true }}
-    needs: [check_access]
     uses: facebook/react/.github/workflows/shared_check_maintainer.yml@main
-    permissions:
-      # Used by check_maintainer
-      contents: read
     with:
       actor: ${{ github.event.pull_request.user.login }}
 
@@ -38,7 +19,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Discord Webhook Action
-        uses: tsickert/discord-webhook@86dc739f3f165f16dadc5666051c367efa1692f4
+        uses: tsickert/discord-webhook@v6.0.0
         with:
           webhook-url: ${{ secrets.DISCORD_WEBHOOK_URL }}
           embed-author-name: ${{ github.event.pull_request.user.login }}

.github/workflows/runtime_eslint_plugin_e2e.yml

@@ -7,8 +7,6 @@ on:
     paths-ignore:
       - compiler/**
 
-permissions: {}
-
 concurrency:
   group: ${{ github.workflow }}-${{ github.ref_name }}-${{ github.event.pull_request.number || github.run_id }}
   cancel-in-progress: true
@@ -37,29 +35,22 @@ jobs:
         with:
           node-version-file: '.nvmrc'
           cache: yarn
-          cache-dependency-path: |
-            yarn.lock
-            compiler/yarn.lock
+          cache-dependency-path: yarn.lock
       - name: Restore cached node_modules
         uses: actions/cache@v4
         id: node_modules
         with:
-          path: |
-            **/node_modules
-          key: runtime-and-compiler-eslint_e2e-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock', 'compiler/yarn.lock', 'fixtures/eslint-v*/yarn.lock') }}
+          path: "node_modules"
+          key: runtime-eslint_e2e-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
       - name: Ensure clean build directory
         run: rm -rf build
       - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
-      - run: yarn --cwd compiler install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
-      - name: Install fixture dependencies
-        working-directory: ./fixtures/eslint-v${{ matrix.eslint_major }}
-        run: yarn --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
       - name: Build plugin
         working-directory: fixtures/eslint-v${{ matrix.eslint_major }}
         run: node build.mjs
+      - name: Install fixture dependencies
+        working-directory: ./fixtures/eslint-v${{ matrix.eslint_major }}
+        run: yarn --frozen-lockfile
       - name: Run lint test
         working-directory: ./fixtures/eslint-v${{ matrix.eslint_major }}
         run: yarn lint

.github/workflows/runtime_fuzz_tests.yml

@@ -8,8 +8,6 @@ on:
       - main
   workflow_dispatch:
 
-permissions: {}
-
 env:
   TZ: /usr/share/zoneinfo/America/Los_Angeles
 

.github/workflows/runtime_prereleases.yml

@@ -13,45 +13,21 @@ on:
       dist_tag:
         required: true
         type: string
-      enableFailureNotification:
-        description: 'Whether to notify the team on Discord when the release fails. Useful if this workflow is called from an automation.'
-        required: false
-        type: boolean
-      only_packages:
-        description: Packages to publish (space separated)
-        type: string
-      skip_packages:
-        description: Packages to NOT publish (space separated)
-        type: string
-      dry:
-        required: true
-        description: Dry run instead of publish?
-        type: boolean
-        default: true
     secrets:
-      DISCORD_WEBHOOK_URL:
-        description: 'Discord webhook URL to notify on failure. Only required if enableFailureNotification is true.'
-        required: false
-      GH_TOKEN:
-        required: true
       NPM_TOKEN:
         required: true
 
-permissions: {}
-
 env:
   TZ: /usr/share/zoneinfo/America/Los_Angeles
   # https://github.com/actions/cache/blob/main/tips-and-workarounds.md#cache-segment-restore-timeout
   SEGMENT_DOWNLOAD_TIMEOUT_MINS: 1
+  GH_TOKEN: ${{ github.token }}
   NPM_TOKEN: ${{ secrets.NPM_TOKEN }}
 
 jobs:
   publish_prerelease:
     name: Publish prelease (${{ inputs.release_channel }}) ${{ inputs.commit_sha }} @${{ inputs.dist_tag }}
     runs-on: ubuntu-latest
-    permissions:
-      # We use github.token to download the build artifact from a previous runtime_build_and_test.yml run
-      actions: read
     steps:
       - uses: actions/checkout@v4
       - uses: actions/setup-node@v4
@@ -63,50 +39,14 @@ jobs:
         uses: actions/cache@v4
         id: node_modules
         with:
-          path: |
-            **/node_modules
-          key: runtime-release-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock', 'scripts/release/yarn.lock') }}
+          path: "**/node_modules"
+          key: runtime-release-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock', 'scripts/release/yarn.lock') }}
       - name: Ensure clean build directory
         run: rm -rf build
       - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
-      - run: yarn --cwd scripts/release install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
-      - run: cp ./scripts/release/ci-npmrc ~/.npmrc
+      - run: yarn install --frozen-lockfile
+        working-directory: scripts/release
       - run: |
-          GH_TOKEN=${{ secrets.GH_TOKEN }} scripts/release/prepare-release-from-ci.js --skipTests -r ${{ inputs.release_channel }} --commit=${{ inputs.commit_sha }}
-      - name: Check prepared files
-        run: ls -R build/node_modules
-      - if: '${{ inputs.only_packages }}'
-        name: 'Publish ${{ inputs.only_packages }}'
-        run: |
-          scripts/release/publish.js \
-            --ci \
-            --skipTests \
-            --tags=${{ inputs.dist_tag }} \
-            --onlyPackages=${{ inputs.only_packages }} ${{ (inputs.dry && '') || '\'}}
-            ${{ inputs.dry && '--dry' || '' }}
-      - if: '${{ inputs.skip_packages }}'
-        name: 'Publish all packages EXCEPT ${{ inputs.skip_packages }}'
-        run: |
-          scripts/release/publish.js \
-            --ci \
-            --skipTests \
-            --tags=${{ inputs.dist_tag }} \
-            --skipPackages=${{ inputs.skip_packages }} ${{ (inputs.dry && '') || '\'}}
-            ${{ inputs.dry && '--dry' || '' }}
-      - if: '${{ !(inputs.skip_packages && inputs.only_packages) }}'
-        name: 'Publish all packages'
-        run: |
-          scripts/release/publish.js \
-            --ci \
-            --tags=${{ inputs.dist_tag }} ${{ (inputs.dry && '') || '\'}}
-            ${{ inputs.dry && '--dry' || '' }}
-      - name: Notify Discord on failure
-        if: failure() && inputs.enableFailureNotification == true
-        uses: tsickert/discord-webhook@86dc739f3f165f16dadc5666051c367efa1692f4
-        with:
-          webhook-url: ${{ secrets.DISCORD_WEBHOOK_URL }}
-          embed-author-name: "GitHub Actions"
-          embed-title: '[Runtime] Publish of ${{ inputs.release_channel }}@${{ inputs.dist_tag}} release failed'
-          embed-url: ${{ github.server_url }}/${{ github.repository }}/actions/runs/${{ github.run_id }}/attempts/${{ github.run_attempt }}
+          scripts/release/prepare-release-from-ci.js --skipTests -r ${{ inputs.release_channel }} --commit=${{ inputs.commit_sha }}
+          cp ./scripts/release/ci-npmrc ~/.npmrc
+          scripts/release/publish.js --ci --tags ${{ inputs.dist_tag }}

.github/workflows/runtime_prereleases_manual.yml

@@ -5,57 +5,15 @@ on:
     inputs:
       prerelease_commit_sha:
         required: true
-      only_packages:
-        description: Packages to publish (space separated)
-        type: string
-      skip_packages:
-        description: Packages to NOT publish (space separated)
-        type: string
-      dry:
-        required: true
-        description: Dry run instead of publish?
-        type: boolean
-        default: true
-      experimental_only:
-        type: boolean
-        description: Only publish to the experimental tag
-        default: false
-      force_notify:
-        description: Force a Discord notification?
-        type: boolean
-        default: false
-
-permissions: {}
 
 env:
   TZ: /usr/share/zoneinfo/America/Los_Angeles
 
 jobs:
-  notify:
-    if: ${{ inputs.force_notify || inputs.dry == false || inputs.dry == 'false' }}
-    runs-on: ubuntu-latest
-    steps:
-      - name: Discord Webhook Action
-        uses: tsickert/discord-webhook@86dc739f3f165f16dadc5666051c367efa1692f4
-        with:
-          webhook-url: ${{ secrets.DISCORD_WEBHOOK_URL }}
-          embed-author-name: ${{ github.event.sender.login }}
-          embed-author-url: ${{ github.event.sender.html_url }}
-          embed-author-icon-url: ${{ github.event.sender.avatar_url }}
-          embed-title: "⚠️ Publishing ${{ inputs.experimental_only && 'EXPERIMENTAL' || 'CANARY & EXPERIMENTAL' }} release ${{ (inputs.dry && ' (dry run)') || '' }}"
-          embed-description: |
-            ```json
-            ${{ toJson(inputs) }}
-            ```
-          embed-url: https://github.com/facebook/react/actions/runs/${{ github.run_id }}
 
   publish_prerelease_canary:
-    if: ${{ !inputs.experimental_only }}
     name: Publish to Canary channel
     uses: facebook/react/.github/workflows/runtime_prereleases.yml@main
-    permissions:
-      # We use github.token to download the build artifact from a previous runtime_build_and_test.yml run
-      actions: read
     with:
       commit_sha: ${{ inputs.prerelease_commit_sha }}
       release_channel: stable
@@ -70,33 +28,20 @@ jobs:
       # downstream consumers might still expect that tag. We can remove this
       # after some time has elapsed and the change has been communicated.
       dist_tag: canary,next
-      only_packages: ${{ inputs.only_packages }}
-      skip_packages: ${{ inputs.skip_packages }}
-      dry: ${{ inputs.dry }}
     secrets:
       NPM_TOKEN: ${{ secrets.NPM_TOKEN }}
-      GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
 
   publish_prerelease_experimental:
     name: Publish to Experimental channel
     uses: facebook/react/.github/workflows/runtime_prereleases.yml@main
-    permissions:
-      # We use github.token to download the build artifact from a previous runtime_build_and_test.yml run
-      actions: read
     # NOTE: Intentionally running these jobs sequentially because npm
     # will sometimes fail if you try to concurrently publish two
     # different versions of the same package, even if they use different
     # dist tags.
     needs: publish_prerelease_canary
-    # Ensures the job runs even if canary is skipped
-    if: always()
     with:
       commit_sha: ${{ inputs.prerelease_commit_sha }}
       release_channel: experimental
       dist_tag: experimental
-      only_packages: ${{ inputs.only_packages }}
-      skip_packages: ${{ inputs.skip_packages }}
-      dry: ${{ inputs.dry }}
     secrets:
       NPM_TOKEN: ${{ secrets.NPM_TOKEN }}
-      GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}

.github/workflows/runtime_prereleases_nightly.yml

@@ -5,8 +5,6 @@ on:
     # At 10 minutes past 16:00 on Mon, Tue, Wed, Thu, and Fri
     - cron: 10 16 * * 1,2,3,4,5
 
-permissions: {}
-
 env:
   TZ: /usr/share/zoneinfo/America/Los_Angeles
 
@@ -14,26 +12,16 @@ jobs:
   publish_prerelease_canary:
     name: Publish to Canary channel
     uses: facebook/react/.github/workflows/runtime_prereleases.yml@main
-    permissions:
-      # We use github.token to download the build artifact from a previous runtime_build_and_test.yml run
-      actions: read
     with:
       commit_sha: ${{ github.sha }}
       release_channel: stable
       dist_tag: canary,next
-      enableFailureNotification: true
-      dry: false
     secrets:
-      DISCORD_WEBHOOK_URL: ${{ secrets.DISCORD_WEBHOOK_URL }}
       NPM_TOKEN: ${{ secrets.NPM_TOKEN }}
-      GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
 
   publish_prerelease_experimental:
     name: Publish to Experimental channel
     uses: facebook/react/.github/workflows/runtime_prereleases.yml@main
-    permissions:
-      # We use github.token to download the build artifact from a previous runtime_build_and_test.yml run
-      actions: read
     # NOTE: Intentionally running these jobs sequentially because npm
     # will sometimes fail if you try to concurrently publish two
     # different versions of the same package, even if they use different
@@ -43,9 +31,5 @@ jobs:
       commit_sha: ${{ github.sha }}
       release_channel: experimental
       dist_tag: experimental
-      enableFailureNotification: true
-      dry: false
     secrets:
-      DISCORD_WEBHOOK_URL: ${{ secrets.DISCORD_WEBHOOK_URL }}
       NPM_TOKEN: ${{ secrets.NPM_TOKEN }}
-      GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}

.github/workflows/runtime_releases_from_npm_manual.yml

@@ -31,12 +31,11 @@ on:
         type: boolean
         default: false
 
-permissions: {}
-
 env:
   TZ: /usr/share/zoneinfo/America/Los_Angeles
   # https://github.com/actions/cache/blob/main/tips-and-workarounds.md#cache-segment-restore-timeout
   SEGMENT_DOWNLOAD_TIMEOUT_MINS: 1
+  GH_TOKEN: ${{ github.token }}
   NPM_TOKEN: ${{ secrets.NPM_TOKEN }}
 
 jobs:
@@ -45,7 +44,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Discord Webhook Action
-        uses: tsickert/discord-webhook@86dc739f3f165f16dadc5666051c367efa1692f4
+        uses: tsickert/discord-webhook@v6.0.0
         with:
           webhook-url: ${{ secrets.DISCORD_WEBHOOK_URL }}
           embed-author-name: ${{ github.event.sender.login }}
@@ -72,15 +71,13 @@ jobs:
         uses: actions/cache@v4
         id: node_modules
         with:
-          path: |
-            **/node_modules
-          key: runtime-release-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock', 'scripts/release/yarn.lock') }}
+          path: "**/node_modules"
+          key: runtime-release-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock', 'scripts/release/yarn.lock') }}
       - name: Ensure clean build directory
         run: rm -rf build
       - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
-      - run: yarn --cwd scripts/release install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
+      - run: yarn install --frozen-lockfile
+        working-directory: scripts/release
       - run: cp ./scripts/release/ci-npmrc ~/.npmrc
       - if: '${{ inputs.only_packages }}'
         name: 'Prepare ${{ inputs.only_packages }} from NPM'
@@ -110,7 +107,7 @@ jobs:
             --tags=${{ inputs.tags }} \
             --publishVersion=${{ inputs.version_to_publish }} \
             --onlyPackages=${{ inputs.only_packages }} ${{ (inputs.dry && '') || '\'}}
-            ${{ inputs.dry && '--dry' || '' }}
+            ${{ inputs.dry && '--dry'}}
       - if: '${{ inputs.skip_packages }}'
         name: 'Publish all packages EXCEPT ${{ inputs.skip_packages }}'
         run: |
@@ -119,7 +116,7 @@ jobs:
             --tags=${{ inputs.tags }} \
             --publishVersion=${{ inputs.version_to_publish }} \
             --skipPackages=${{ inputs.skip_packages }} ${{ (inputs.dry && '') || '\'}}
-            ${{ inputs.dry && '--dry' || '' }}
+            ${{ inputs.dry && '--dry'}}
       - name: Archive released package for debugging
         uses: actions/upload-artifact@v4
         with:

.github/workflows/shared_check_maintainer.yml

@@ -6,12 +6,14 @@ on:
       actor:
         required: true
         type: string
+      is_remote:
+        required: false
+        type: boolean
+        default: false
     outputs:
       is_core_team:
         value: ${{ jobs.check_maintainer.outputs.is_core_team }}
 
-permissions: {}
-
 env:
   TZ: /usr/share/zoneinfo/America/Los_Angeles
   # https://github.com/actions/cache/blob/main/tips-and-workarounds.md#cache-segment-restore-timeout
@@ -20,12 +22,10 @@ env:
 jobs:
   check_maintainer:
     runs-on: ubuntu-latest
-    permissions:
-      # We fetch the contents of the MAINTAINERS file
-      contents: read
     outputs:
       is_core_team: ${{ steps.check_if_actor_is_maintainer.outputs.result }}
     steps:
+      - uses: actions/checkout@v4
       - name: Check if actor is maintainer
         id: check_if_actor_is_maintainer
         uses: actions/github-script@v7
@@ -33,20 +33,33 @@ jobs:
           script: |
             const fs = require('fs');
             const actor = '${{ inputs.actor }}';
-            const res = await github.rest.repos.getContent({
-              owner: 'facebook',
-              repo: 'react',
-              path: 'MAINTAINERS',
-              ref: 'main',
-              headers: { Accept: 'application/vnd.github+json' }
-            });
-            if (res.status !== 200) {
-              console.error(res);
-              throw new Error('Unable to fetch MAINTAINERS file');
+            let isRemote = ${{ inputs.is_remote }};
+            if (typeof isRemote === 'string') {
+              isRemote = isRemote === 'true';
             }
-            content = Buffer.from(res.data.content, 'base64').toString();
-            if (content == null || typeof content !== 'string') {
-              throw new Error('Unable to retrieve MAINTAINERS file');
+            if (typeof isRemote !== 'boolean') {
+              throw new Error(`Invalid \`isRemote\` input. Expected a boolean, got: ${isRemote}`);
+            }
+
+            let content = null;
+            if (isRemote === true) {
+              const res = await github.rest.repos.getContent({
+                owner: 'facebook',
+                repo: 'react',
+                path: 'MAINTAINERS',
+                ref: 'main',
+                headers: { Accept: 'application/vnd.github+json' }
+              });
+              if (res.status !== 200) {
+                console.error(res);
+                throw new Error('Unable to fetch MAINTAINERS file');
+              }
+              content = Buffer.from(res.data.content, 'base64').toString();
+            } else {
+              content = await fs.readFileSync('./MAINTAINERS', { encoding: 'utf8' });
+            }
+            if (content === null) {
+              throw new Error('Unable to retrieve local or http MAINTAINERS file');
             }
 
             const maintainers = new Set(content.split('\n'));

.github/workflows/shared_cleanup_merged_branch_caches.yml

@@ -1,41 +0,0 @@
-# https://github.com/actions/cache/blob/main/tips-and-workarounds.md#force-deletion-of-caches-overriding-default-cache-eviction-policy
-
-name: (Shared) Cleanup Merged Branch Caches
-on:
-  pull_request:
-    types:
-      - closed
-  workflow_dispatch:
-    inputs:
-      pr_number:
-        required: true
-        type: string
-
-permissions: {}
-
-jobs:
-  cleanup:
-    runs-on: ubuntu-latest
-    permissions:
-      # `actions:write` permission is required to delete caches
-      #   See also: https://docs.github.com/en/rest/actions/cache?apiVersion=2022-11-28#delete-a-github-actions-cache-for-a-repository-using-a-cache-id
-      actions: write
-      contents: read
-    steps:
-      - name: Cleanup
-        run: |
-          echo "Fetching list of cache key"
-          cacheKeysForPR=$(gh cache list --ref $BRANCH --limit 100 --json id --jq '.[].id')
-
-          ## Setting this to not fail the workflow while deleting cache keys.
-          set +e
-          for cacheKey in $cacheKeysForPR
-          do
-              gh cache delete $cacheKey
-              echo "Deleting $cacheKey"
-          done
-          echo "Done"
-        env:
-          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
-          GH_REPO: ${{ github.repository }}
-          BRANCH: refs/pull/${{ inputs.pr_number || github.event.pull_request.number }}/merge

.github/workflows/shared_cleanup_stale_branch_caches.yml

@@ -1,36 +0,0 @@
-# https://github.com/actions/cache/blob/main/tips-and-workarounds.md#force-deletion-of-caches-overriding-default-cache-eviction-policy
-
-name: (Shared) Cleanup Stale Branch Caches
-on:
-  schedule:
-    # Every 6 hours
-    - cron: 0 */6 * * *
-  workflow_dispatch:
-
-permissions: {}
-
-jobs:
-  cleanup:
-    runs-on: ubuntu-latest
-    permissions:
-      # `actions:write` permission is required to delete caches
-      #   See also: https://docs.github.com/en/rest/actions/cache?apiVersion=2022-11-28#delete-a-github-actions-cache-for-a-repository-using-a-cache-id
-      actions: write
-      contents: read
-    steps:
-      - name: Cleanup
-        run: |
-          echo "Fetching list of cache keys"
-          cacheKeysForPR=$(gh cache list --limit 100 --json id,ref --jq '.[] | select(.ref != "refs/heads/main") | .id')
-
-          ## Setting this to not fail the workflow while deleting cache keys.
-          set +e
-          for cacheKey in $cacheKeysForPR
-          do
-              gh cache delete $cacheKey
-              echo "Deleting $cacheKey"
-          done
-          echo "Done"
-        env:
-          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
-          GH_REPO: ${{ github.repository }}

.github/workflows/shared_close_direct_sync_branch_prs.yml

@@ -5,8 +5,6 @@ on:
     branches:
       - 'builds/facebook-**'
 
-permissions: {}
-
 env:
   TZ: /usr/share/zoneinfo/America/Los_Angeles
   # https://github.com/actions/cache/blob/main/tips-and-workarounds.md#cache-segment-restore-timeout
@@ -15,9 +13,6 @@ env:
 jobs:
   close_pr:
     runs-on: ubuntu-latest
-    permissions:
-      # Used to create a review and close PRs
-      pull-requests: write
     steps:
       - name: Close PR
         uses: actions/github-script@v7

.github/workflows/shared_label_core_team_prs.yml

@@ -2,9 +2,6 @@ name: (Shared) Label Core Team PRs
 
 on:
   pull_request_target:
-    types: [opened]
-
-permissions: {}
 
 env:
   TZ: /usr/share/zoneinfo/America/Los_Angeles
@@ -12,24 +9,8 @@ env:
   SEGMENT_DOWNLOAD_TIMEOUT_MINS: 1
 
 jobs:
-  check_access:
-    runs-on: ubuntu-latest
-    outputs:
-      is_member_or_collaborator: ${{ steps.check_is_member_or_collaborator.outputs.is_member_or_collaborator }}
-    steps:
-      - run: echo ${{ github.event.pull_request.author_association }}
-      - name: Check is member or collaborator
-        id: check_is_member_or_collaborator
-        if: ${{ github.event.pull_request.author_association == 'MEMBER' || github.event.pull_request.author_association == 'COLLABORATOR' }}
-        run: echo "is_member_or_collaborator=true" >> "$GITHUB_OUTPUT"
-
   check_maintainer:
-    if: ${{ needs.check_access.outputs.is_member_or_collaborator == 'true' || needs.check_access.outputs.is_member_or_collaborator == true }}
-    needs: [check_access]
     uses: facebook/react/.github/workflows/shared_check_maintainer.yml@main
-    permissions:
-      # Used by check_maintainer
-      contents: read
     with:
       actor: ${{ github.event.pull_request.user.login }}
 
@@ -37,11 +18,6 @@ jobs:
     if: ${{ needs.check_maintainer.outputs.is_core_team == 'true' }}
     runs-on: ubuntu-latest
     needs: check_maintainer
-    permissions:
-      # Used to add labels on issues
-      issues: write
-      # Used to add labels on PRs
-      pull-requests: write
     steps:
       - name: Label PR as React Core Team
         uses: actions/github-script@v7

.github/workflows/shared_lint.yml

@@ -5,8 +5,6 @@ on:
     branches: [main]
   pull_request:
 
-permissions: {}
-
 concurrency:
   group: ${{ github.workflow }}-${{ github.ref_name }}-${{ github.event.pull_request.number || github.run_id }}
   cancel-in-progress: true
@@ -29,15 +27,12 @@ jobs:
           cache-dependency-path: yarn.lock
       - name: Restore cached node_modules
         uses: actions/cache@v4
-        id: node_modules
         with:
-          path: |
-            **/node_modules
-          key: shared-lint-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('**/yarn.lock') }}
+          path: "**/node_modules"
+          key: shared-lint-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('**/yarn.lock') }}
       - name: Ensure clean build directory
         run: rm -rf build
       - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
       - run: yarn prettier-check
 
   eslint:
@@ -52,15 +47,12 @@ jobs:
           cache-dependency-path: yarn.lock
       - name: Restore cached node_modules
         uses: actions/cache@v4
-        id: node_modules
         with:
-          path: |
-            **/node_modules
-          key: shared-lint-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('**/yarn.lock') }}
+          path: "**/node_modules"
+          key: shared-lint-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('**/yarn.lock') }}
       - name: Ensure clean build directory
         run: rm -rf build
       - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
       - run: node ./scripts/tasks/eslint
 
   check_license:
@@ -75,15 +67,12 @@ jobs:
           cache-dependency-path: yarn.lock
       - name: Restore cached node_modules
         uses: actions/cache@v4
-        id: node_modules
         with:
-          path: |
-            **/node_modules
-          key: shared-lint-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('**/yarn.lock') }}
+          path: "**/node_modules"
+          key: shared-lint-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('**/yarn.lock') }}
       - name: Ensure clean build directory
         run: rm -rf build
       - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
       - run: ./scripts/ci/check_license.sh
 
   test_print_warnings:
@@ -98,13 +87,10 @@ jobs:
           cache-dependency-path: yarn.lock
       - name: Restore cached node_modules
         uses: actions/cache@v4
-        id: node_modules
         with:
-          path: |
-            **/node_modules
-          key: shared-lint-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('**/yarn.lock') }}
+          path: "**/node_modules"
+          key: shared-lint-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('**/yarn.lock') }}
       - name: Ensure clean build directory
         run: rm -rf build
       - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
       - run: ./scripts/ci/test_print_warnings.sh

.github/workflows/shared_stale.yml

@@ -6,11 +6,6 @@ on:
     - cron: '0 * * * *'
   workflow_dispatch:
 
-permissions:
-  # https://github.com/actions/stale/tree/v9/?tab=readme-ov-file#recommended-permissions
-  issues: write
-  pull-requests: write
-
 env:
   TZ: /usr/share/zoneinfo/America/Los_Angeles
 

.nvmrc

@@ -1 +1 @@
-v20.19.0
+v18.20.1

.prettierrc.js

@@ -3,12 +3,13 @@
 const {esNextPaths} = require('./scripts/shared/pathsByLanguageVersion');
 
 module.exports = {
+  plugins: ['prettier-plugin-hermes-parser'],
   bracketSpacing: false,
   singleQuote: true,
   bracketSameLine: true,
   trailingComma: 'es5',
   printWidth: 80,
-  parser: 'flow',
+  parser: 'hermes',
   arrowParens: 'avoid',
   overrides: [
     {

CHANGELOG-canary.md

@@ -0,0 +1,18 @@
+## March 22, 2024 (18.3.0-canary-670811593-20240322)
+
+## React
+- Added `useActionState` to replace `useFormState` and added `pending` value ([#28491](https://github.com/facebook/react/pull/28491)).
+
+## October 5, 2023 (18.3.0-canary-546178f91-20231005)
+
+### React
+
+- Added support for async functions to be passed to `startTransition`. 
+- `useTransition` now triggers the nearest error boundary instead of a global error.
+- Added `useOptimistic`, a new Hook for handling optimistic UI updates. It optimistically updates the UI before receiving confirmation from a server or external source.
+
+### React DOM
+
+- Added support for passing async functions to the `action` prop on `<form>`. When the function passed to `action` is marked with [`'use server'`](https://react.dev/reference/react/use-server), the form is [progressively enhanced](https://developer.mozilla.org/en-US/docs/Glossary/Progressive_Enhancement).
+- Added `useFormStatus`, a new Hook for checking the submission state of a form.
+- Added `useFormState`, a new Hook for updating state upon form submission. When the function passed to `useFormState` is marked with [`'use server'`](https://react.dev/reference/react/use-server), the update is [progressively enhanced](https://developer.mozilla.org/en-US/docs/Glossary/Progressive_Enhancement).

CHANGELOG.md

@@ -1,55 +1,3 @@
-## 19.1.1 (July 28, 2025)
-
-### React
-* Fixed Owner Stacks to work with ES2015 function.name semantics ([#33680](https://github.com/facebook/react/pull/33680) by @hoxyq)
-
-## 19.1.0 (March 28, 2025)
-
-### Owner Stack
-
-An Owner Stack is a string representing the components that are directly responsible for rendering a particular component. You can log Owner Stacks when debugging or use Owner Stacks to enhance error overlays or other development tools. Owner Stacks are only available in development builds. Component Stacks in production are unchanged.
-
-* An Owner Stack is a development-only stack trace that helps identify which components are responsible for rendering a particular component. An Owner Stack is distinct from a Component Stacks, which shows the hierarchy of components leading to an error.
-* The [captureOwnerStack API](https://react.dev/reference/react/captureOwnerStack) is only available in development mode and returns a Owner Stack, if available. The API can be used to enhance error overlays or log component relationships when debugging. [#29923](https://github.com/facebook/react/pull/29923), [#32353](https://github.com/facebook/react/pull/32353), [#30306](https://github.com/facebook/react/pull/30306),
-[#32538](https://github.com/facebook/react/pull/32538), [#32529](https://github.com/facebook/react/pull/32529), [#32538](https://github.com/facebook/react/pull/32538)
-
-### React
-* Enhanced support for Suspense boundaries to be used anywhere, including the client, server, and during hydration. [#32069](https://github.com/facebook/react/pull/32069), [#32163](https://github.com/facebook/react/pull/32163), [#32224](https://github.com/facebook/react/pull/32224), [#32252](https://github.com/facebook/react/pull/32252)
-* Reduced unnecessary client rendering through improved hydration scheduling [#31751](https://github.com/facebook/react/pull/31751)
-* Increased priority of client rendered Suspense boundaries [#31776](https://github.com/facebook/react/pull/31776)
-* Fixed frozen fallback states by rendering unfinished Suspense boundaries on the client. [#31620](https://github.com/facebook/react/pull/31620)
-* Reduced garbage collection pressure by improving Suspense boundary retries. [#31667](https://github.com/facebook/react/pull/31667)
-* Fixed erroneous “Waiting for Paint” log when the passive effect phase was not delayed [#31526](https://github.com/facebook/react/pull/31526)
-* Fixed a regression causing key warnings for flattened positional children in development mode. [#32117](https://github.com/facebook/react/pull/32117)
-* Updated `useId` to use valid CSS selectors, changing format from `:r123:` to `«r123»`. [#32001](https://github.com/facebook/react/pull/32001)
-* Added a dev-only warning for null/undefined created in useEffect, useInsertionEffect, and useLayoutEffect. [#32355](https://github.com/facebook/react/pull/32355)
-* Fixed a bug where dev-only methods were exported in production builds. React.act is no longer available in production builds. [#32200](https://github.com/facebook/react/pull/32200)
-* Improved consistency across prod and dev to improve compatibility with Google Closure Compiler and bindings [#31808](https://github.com/facebook/react/pull/31808)
-* Improve passive effect scheduling for consistent task yielding. [#31785](https://github.com/facebook/react/pull/31785)
-* Fixed asserts in React Native when passChildrenWhenCloningPersistedNodes is enabled for OffscreenComponent rendering. [#32528](https://github.com/facebook/react/pull/32528)
-* Fixed component name resolution for Portal [#32640](https://github.com/facebook/react/pull/32640)
-* Added support for beforetoggle and toggle events on the dialog element. [#32479](https://github.com/facebook/react/pull/32479)
-
-### React DOM
-* Fixed double warning when the `href` attribute is an empty string [#31783](https://github.com/facebook/react/pull/31783)
- * Fixed an edge case where `getHoistableRoot()` didn’t work properly when the container was a Document [#32321](https://github.com/facebook/react/pull/32321)
-* Removed support for using HTML comments (e.g. `<!-- -->`) as a DOM container. [#32250](https://github.com/facebook/react/pull/32250)
-* Added support for `<script>` and `<template>` tags to be nested within `<select>` tags. [#31837](https://github.com/facebook/react/pull/31837)
-* Fixed responsive images to be preloaded as HTML instead of headers [#32445](https://github.com/facebook/react/pull/32445)
-
-### use-sync-external-store
-* Added `exports` field to `package.json` for `use-sync-external-store` to support various entrypoints. [#25231](https://github.com/facebook/react/pull/25231)
-
-### React Server Components
-* Added `unstable_prerender`, a new experimental API for prerendering React Server Components on the server [#31724](https://github.com/facebook/react/pull/31724)
-* Fixed an issue where streams would hang when receiving new chunks after a global error [#31840](https://github.com/facebook/react/pull/31840), [#31851](https://github.com/facebook/react/pull/31851)
-* Fixed an issue where pending chunks were counted twice. [#31833](https://github.com/facebook/react/pull/31833)
-* Added support for streaming in edge environments [#31852](https://github.com/facebook/react/pull/31852)
-* Added support for sending custom error names from a server so that they are available in the client for console replaying. [#32116](https://github.com/facebook/react/pull/32116)
-* Updated the server component wire format to remove IDs for hints and console.log because they have no return value [#31671](https://github.com/facebook/react/pull/31671)
-* Exposed `registerServerReference` in client builds to handle server references in different environments. [#32534](https://github.com/facebook/react/pull/32534)
-* Added react-server-dom-parcel package which integrates Server Components with the [Parcel bundler](https://parceljs.org/) [#31725](https://github.com/facebook/react/pull/31725), [#32132](https://github.com/facebook/react/pull/32132), [#31799](https://github.com/facebook/react/pull/31799), [#32294](https://github.com/facebook/react/pull/32294), [#31741](https://github.com/facebook/react/pull/31741)
-
 ## 19.0.0 (December 5, 2024)
 
 Below is a list of all new features, APIs, deprecations, and breaking changes. Read [React 19 release post](https://react.dev/blog/2024/04/25/react-19) and [React 19 upgrade guide](https://react.dev/blog/2024/04/25/react-19-upgrade-guide) for more information.

ReactVersions.js

@@ -18,7 +18,7 @@
 //
 //   0.0.0-experimental-241c4467e-20200129
 
-const ReactVersion = '19.2.0';
+const ReactVersion = '19.1.0';
 
 // The label used by the @canary channel. Represents the upcoming release's
 // stability. Most of the time, this will be "canary", but we may temporarily
@@ -33,7 +33,7 @@ const canaryChannelLabel = 'canary';
 const rcNumber = 0;
 
 const stablePackages = {
-  'eslint-plugin-react-hooks': '6.1.0',
+  'eslint-plugin-react-hooks': '5.2.0',
   'jest-react': '0.17.0',
   react: ReactVersion,
   'react-art': ReactVersion,
@@ -42,12 +42,12 @@ const stablePackages = {
   'react-server-dom-turbopack': ReactVersion,
   'react-server-dom-parcel': ReactVersion,
   'react-is': ReactVersion,
-  'react-reconciler': '0.33.0',
-  'react-refresh': '0.18.0',
+  'react-reconciler': '0.32.0',
+  'react-refresh': '0.17.0',
   'react-test-renderer': ReactVersion,
-  'use-subscription': '1.12.0',
-  'use-sync-external-store': '1.6.0',
-  scheduler: '0.27.0',
+  'use-subscription': '1.11.0',
+  'use-sync-external-store': '1.5.0',
+  scheduler: '0.26.0',
 };
 
 // These packages do not exist in the @canary or @latest channel, only

babel.config.js

@@ -4,7 +4,8 @@ module.exports = {
   plugins: [
     '@babel/plugin-syntax-jsx',
     '@babel/plugin-transform-flow-strip-types',
-    ['@babel/plugin-proposal-class-properties', {loose: true}],
+    ['@babel/plugin-transform-class-properties', {loose: true}],
+    '@babel/plugin-transform-classes',
     'syntax-trailing-function-commas',
     [
       '@babel/plugin-proposal-object-rest-spread',

compiler/.gitignore

@@ -1,14 +1,28 @@
 .DS_Store
 .spr.yml
 
+# Generated by Cargo
+# will have compiled files and executables
+debug/
+target/
+
+# These are backup files generated by rustfmt
+**/*.rs.bk
+
+# MSVC Windows builds of rustc generate these, which store debugging information
+*.pdb
+
 node_modules
 .watchmanconfig
 .watchman-cookie-*
 dist
 .vscode
 !packages/playground/.vscode
+.spr.yml
 testfilter.txt
 
+bundle-oss.sh
+
 # forgive
 *.vsix
 .vscode-test

compiler/CHANGELOG.md

@@ -1,65 +0,0 @@
-## 19.1.0-rc.2 (May 14, 2025)
-
-## babel-plugin-react-compiler
-
-* Fix for string attribute values with emoji [#33096](https://github.com/facebook/react/pull/33096) by [@josephsavona](https://github.com/josephsavona)
-
-## 19.1.0-rc.1 (April 21, 2025)
-
-## eslint-plugin-react-hooks
-* Temporarily disable ref access in render validation [#32839](https://github.com/facebook/react/pull/32839) by [@poteto](https://github.com/poteto)
-* Fix type error with recommended config [#32666](https://github.com/facebook/react/pull/32666) by [@niklasholm](https://github.com/niklasholm)
-* Merge rule from eslint-plugin-react-compiler into `react-hooks` plugin [#32416](https://github.com/facebook/react/pull/32416) by [@michaelfaith](https://github.com/michaelfaith)
-* Add dev dependencies for typescript migration [#32279](https://github.com/facebook/react/pull/32279) by [@michaelfaith](https://github.com/michaelfaith)
-* Support v9 context api [#32045](https://github.com/facebook/react/pull/32045) by [@michaelfaith](https://github.com/michaelfaith)
-* Support eslint 8+ flat plugin syntax out of the box for eslint-plugin-react-compiler [#32120](https://github.com/facebook/react/pull/32120) by [@orta](https://github.com/orta)
-
-## babel-plugin-react-compiler
-* Support satisfies operator [#32742](https://github.com/facebook/react/pull/32742) by [@rodrigofariow](https://github.com/rodrigofariow)
-* Fix inferEffectDependencies lint false positives [#32769](https://github.com/facebook/react/pull/32769) by [@mofeiZ](https://github.com/mofeiZ)
-* Fix hoisting of let declarations [#32724](https://github.com/facebook/react/pull/32724) by [@mofeiZ](https://github.com/mofeiZ)
-* Avoid failing builds when import specifiers conflict or shadow vars [#32663](https://github.com/facebook/react/pull/32663) by [@mofeiZ](https://github.com/mofeiZ)
-* Optimize components declared with arrow function and implicit return and `compilationMode: 'infer'` [#31792](https://github.com/facebook/react/pull/31792) by [@dimaMachina](https://github.com/dimaMachina)
-* Validate static components [#32683](https://github.com/facebook/react/pull/32683) by [@josephsavona](https://github.com/josephsavona)
-* Hoist dependencies from functions more conservatively [#32616](https://github.com/facebook/react/pull/32616) by [@mofeiZ](https://github.com/mofeiZ)
-* Implement NumericLiteral as ObjectPropertyKey [#31791](https://github.com/facebook/react/pull/31791) by [@dimaMachina](https://github.com/dimaMachina)
-* Avoid bailouts when inserting gating [#32598](https://github.com/facebook/react/pull/32598) by [@mofeiZ](https://github.com/mofeiZ)
-* Stop bailing out early for hoisted gated functions [#32597](https://github.com/facebook/react/pull/32597) by [@mofeiZ](https://github.com/mofeiZ)
-* Add shape for Array.from [#32522](https://github.com/facebook/react/pull/32522) by [@mofeiZ](https://github.com/mofeiZ)
-* Patch array and argument spread mutability [#32521](https://github.com/facebook/react/pull/32521) by [@mofeiZ](https://github.com/mofeiZ)
-* Make CompilerError compatible with reflection [#32539](https://github.com/facebook/react/pull/32539) by [@poteto](https://github.com/poteto)
-* Add simple walltime measurement [#32331](https://github.com/facebook/react/pull/32331) by [@poteto](https://github.com/poteto)
-* Improve error messages for unhandled terminal and instruction kinds [#32324](https://github.com/facebook/react/pull/32324) by [@inottn](https://github.com/inottn)
-* Handle TSInstantiationExpression in lowerExpression [#32302](https://github.com/facebook/react/pull/32302) by [@inottn](https://github.com/inottn)
-* Fix invalid Array.map type [#32095](https://github.com/facebook/react/pull/32095) by [@mofeiZ](https://github.com/mofeiZ)
-* Patch for JSX escape sequences in @babel/generator [#32131](https://github.com/facebook/react/pull/32131) by [@mofeiZ](https://github.com/mofeiZ)
-* `JSXText` emits incorrect with bracket [#32138](https://github.com/facebook/react/pull/32138) by [@himself65](https://github.com/himself65)
-* Validation against calling impure functions [#31960](https://github.com/facebook/react/pull/31960) by [@josephsavona](https://github.com/josephsavona)
-* Always target node [#32091](https://github.com/facebook/react/pull/32091) by [@poteto](https://github.com/poteto)
-* Patch compilationMode:infer object method edge case [#32055](https://github.com/facebook/react/pull/32055) by [@mofeiZ](https://github.com/mofeiZ)
-* Generate ts defs [#31994](https://github.com/facebook/react/pull/31994) by [@poteto](https://github.com/poteto)
-* Relax react peer dep requirement [#31915](https://github.com/facebook/react/pull/31915) by [@poteto](https://github.com/poteto)
-* Allow type cast expressions with refs [#31871](https://github.com/facebook/react/pull/31871) by [@josephsavona](https://github.com/josephsavona)
-* Add shape for global Object.keys [#31583](https://github.com/facebook/react/pull/31583) by [@mofeiZ](https://github.com/mofeiZ)
-* Optimize method calls w props receiver [#31775](https://github.com/facebook/react/pull/31775) by [@josephsavona](https://github.com/josephsavona)
-* Fix dropped ref with spread props in InlineJsxTransform [#31726](https://github.com/facebook/react/pull/31726) by [@jackpope](https://github.com/jackpope)
-* Support for non-declatation for in/of iterators [#31710](https://github.com/facebook/react/pull/31710) by [@mvitousek](https://github.com/mvitousek)
-* Support for context variable loop iterators [#31709](https://github.com/facebook/react/pull/31709) by [@mvitousek](https://github.com/mvitousek)
-* Replace deprecated dependency in `eslint-plugin-react-compiler` [#31629](https://github.com/facebook/react/pull/31629) by [@rakleed](https://github.com/rakleed)
-* Support enableRefAsProp in jsx transform [#31558](https://github.com/facebook/react/pull/31558) by [@jackpope](https://github.com/jackpope)
-* Fix: ref.current now correctly reactive [#31521](https://github.com/facebook/react/pull/31521) by [@mofeiZ](https://github.com/mofeiZ)
-* Outline JSX with non-jsx children [#31442](https://github.com/facebook/react/pull/31442) by [@gsathya](https://github.com/gsathya)
-* Outline jsx with duplicate attributes [#31441](https://github.com/facebook/react/pull/31441) by [@gsathya](https://github.com/gsathya)
-* Store original and new prop names [#31440](https://github.com/facebook/react/pull/31440) by [@gsathya](https://github.com/gsathya)
-* Stabilize compiler output: sort deps and decls by name [#31362](https://github.com/facebook/react/pull/31362) by [@mofeiZ](https://github.com/mofeiZ)
-* Bugfix for hoistable deps for nested functions [#31345](https://github.com/facebook/react/pull/31345) by [@mofeiZ](https://github.com/mofeiZ)
-* Remove compiler runtime-compat fixture library [#31430](https://github.com/facebook/react/pull/31430) by [@poteto](https://github.com/poteto)
-* Wrap inline jsx transform codegen in conditional [#31267](https://github.com/facebook/react/pull/31267) by [@jackpope](https://github.com/jackpope)
-* Check if local identifier is a hook when resolving globals [#31384](https://github.com/facebook/react/pull/31384) by [@poteto](https://github.com/poteto)
-* Handle member expr as computed property [#31344](https://github.com/facebook/react/pull/31344) by [@gsathya](https://github.com/gsathya)
-* Fix to ref access check to ban ref?.current [#31360](https://github.com/facebook/react/pull/31360) by [@mvitousek](https://github.com/mvitousek)
-* InlineJSXTransform transforms jsx inside function expressions [#31282](https://github.com/facebook/react/pull/31282) by [@josephsavona](https://github.com/josephsavona)
-
-## Other
-* Add shebang to banner [#32225](https://github.com/facebook/react/pull/32225) by [@Jeremy-Hibiki](https://github.com/Jeremy-Hibiki)
-* remove terser from react-compiler-runtime build [#31326](https://github.com/facebook/react/pull/31326) by [@henryqdineen](https://github.com/henryqdineen)

compiler/apps/playground/__tests__/e2e/__snapshots__/page.spec.ts/compilationMode-all-output.txt

@@ -1,5 +1,5 @@
 import { c as _c } from "react/compiler-runtime"; // 
-@compilationMode:"all"
+        @compilationMode(all)
 function nonReactFn() {
   const $ = _c(1);
   let t0;

compiler/apps/playground/__tests__/e2e/__snapshots__/page.spec.ts/compilationMode-infer-output.txt

@@ -1,4 +1,4 @@
-// @compilationMode:"infer"
+// @compilationMode(infer)
 function nonReactFn() {
   return {};
 }

compiler/apps/playground/__tests__/e2e/page.spec.ts

@@ -92,7 +92,7 @@ function useFoo(propVal: {+baz: number}) {
   },
   {
     name: 'compilationMode-infer',
-    input: `// @compilationMode:"infer"
+    input: `// @compilationMode(infer)
 function nonReactFn() {
   return {};
 }
@@ -101,7 +101,7 @@ function nonReactFn() {
   },
   {
     name: 'compilationMode-all',
-    input: `// @compilationMode:"all"
+    input: `// @compilationMode(all)
 function nonReactFn() {
   return {};
 }

compiler/apps/playground/components/Editor/EditorImpl.tsx

@@ -11,7 +11,6 @@ import * as t from '@babel/types';
 import BabelPluginReactCompiler, {
   CompilerError,
   CompilerErrorDetail,
-  CompilerDiagnostic,
   Effect,
   ErrorSeverity,
   parseConfigPragmaForTests,
@@ -20,9 +19,7 @@ import BabelPluginReactCompiler, {
   PluginOptions,
   CompilerPipelineValue,
   parsePluginOptions,
-  printReactiveFunctionWithOutlined,
-  printFunctionWithOutlined,
-} from 'babel-plugin-react-compiler';
+} from 'babel-plugin-react-compiler/src';
 import clsx from 'clsx';
 import invariant from 'invariant';
 import {useSnackbar} from 'notistack';
@@ -44,8 +41,9 @@ import {
   default as Output,
   PrintedCompilerPipelineValue,
 } from './Output';
+import {printFunctionWithOutlined} from 'babel-plugin-react-compiler/src/HIR/PrintHIR';
+import {printReactiveFunctionWithOutlined} from 'babel-plugin-react-compiler/src/ReactiveScopes/PrintReactiveFunction';
 import {transformFromAstSync} from '@babel/core';
-import {LoggerEvent} from 'babel-plugin-react-compiler/dist/Entrypoint';
 
 function parseInput(
   input: string,
@@ -142,13 +140,9 @@ const COMMON_HOOKS: Array<[string, Hook]> = [
   ],
 ];
 
-function compile(
-  source: string,
-  mode: 'compiler' | 'linter',
-): [CompilerOutput, 'flow' | 'typescript'] {
+function compile(source: string): [CompilerOutput, 'flow' | 'typescript'] {
   const results = new Map<string, Array<PrintedCompilerPipelineValue>>();
   const error = new CompilerError();
-  const otherErrors: Array<CompilerErrorDetail | CompilerDiagnostic> = [];
   const upsert: (result: PrintedCompilerPipelineValue) => void = result => {
     const entry = results.get(result.name);
     if (Array.isArray(entry)) {
@@ -207,23 +201,6 @@ function compile(
     };
     const parsedOptions = parseConfigPragmaForTests(pragma, {
       compilationMode: 'infer',
-      environment:
-        mode === 'linter'
-          ? {
-              // enabled in compiler
-              validateRefAccessDuringRender: false,
-              // enabled in linter
-              validateNoSetStateInRender: true,
-              validateNoSetStateInEffects: true,
-              validateNoJSXInTryStatements: true,
-              validateNoImpureFunctionsInRender: true,
-              validateStaticComponents: true,
-              validateNoFreezingKnownMutableFunctions: true,
-              validateNoVoidUseMemo: true,
-            }
-          : {
-              /* use defaults for compiler mode */
-            },
     });
     const opts: PluginOptions = parsePluginOptions({
       ...parsedOptions,
@@ -233,11 +210,7 @@ function compile(
       },
       logger: {
         debugLogIRs: logIR,
-        logEvent: (_filename: string | null, event: LoggerEvent) => {
-          if (event.kind === 'CompileError') {
-            otherErrors.push(event.detail);
-          }
-        },
+        logEvent: () => {},
       },
     });
     transformOutput = invokeCompiler(source, language, opts);
@@ -247,7 +220,7 @@ function compile(
      * (i.e. object shape that is not CompilerError)
      */
     if (err instanceof CompilerError && err.details.length > 0) {
-      error.merge(err);
+      error.details.push(...err.details);
     } else {
       /**
        * Handle unexpected failures by logging (to get a stack trace)
@@ -264,17 +237,10 @@ function compile(
       );
     }
   }
-  // Only include logger errors if there weren't other errors
-  if (!error.hasErrors() && otherErrors.length !== 0) {
-    otherErrors.forEach(e => error.details.push(e));
-  }
   if (error.hasErrors()) {
-    return [{kind: 'err', results, error}, language];
+    return [{kind: 'err', results, error: error}, language];
   }
-  return [
-    {kind: 'ok', results, transformOutput, errors: error.details},
-    language,
-  ];
+  return [{kind: 'ok', results, transformOutput}, language];
 }
 
 export default function Editor(): JSX.Element {
@@ -283,11 +249,7 @@ export default function Editor(): JSX.Element {
   const dispatchStore = useStoreDispatch();
   const {enqueueSnackbar} = useSnackbar();
   const [compilerOutput, language] = useMemo(
-    () => compile(deferredStore.source, 'compiler'),
-    [deferredStore.source],
-  );
-  const [linterOutput] = useMemo(
-    () => compile(deferredStore.source, 'linter'),
+    () => compile(deferredStore.source),
     [deferredStore.source],
   );
 
@@ -313,26 +275,19 @@ export default function Editor(): JSX.Element {
     });
   });
 
-  let mergedOutput: CompilerOutput;
-  let errors: Array<CompilerErrorDetail | CompilerDiagnostic>;
-  if (compilerOutput.kind === 'ok') {
-    errors = linterOutput.kind === 'ok' ? [] : linterOutput.error.details;
-    mergedOutput = {
-      ...compilerOutput,
-      errors,
-    };
-  } else {
-    mergedOutput = compilerOutput;
-    errors = compilerOutput.error.details;
-  }
   return (
     <>
       <div className="relative flex basis top-14">
         <div className={clsx('relative sm:basis-1/4')}>
-          <Input language={language} errors={errors} />
+          <Input
+            language={language}
+            errors={
+              compilerOutput.kind === 'err' ? compilerOutput.error.details : []
+            }
+          />
         </div>
         <div className={clsx('flex sm:flex flex-wrap')}>
-          <Output store={deferredStore} compilerOutput={mergedOutput} />
+          <Output store={deferredStore} compilerOutput={compilerOutput} />
         </div>
       </div>
     </>

compiler/apps/playground/components/Editor/Input.tsx

@@ -6,7 +6,7 @@
  */
 
 import MonacoEditor, {loader, type Monaco} from '@monaco-editor/react';
-import {CompilerErrorDetail} from 'babel-plugin-react-compiler';
+import {CompilerErrorDetail} from 'babel-plugin-react-compiler/src';
 import invariant from 'invariant';
 import type {editor} from 'monaco-editor';
 import * as monaco from 'monaco-editor';
@@ -36,18 +36,13 @@ export default function Input({errors, language}: Props): JSX.Element {
     const uri = monaco.Uri.parse(`file:///index.js`);
     const model = monaco.editor.getModel(uri);
     invariant(model, 'Model must exist for the selected input file.');
-    renderReactCompilerMarkers({
-      monaco,
-      model,
-      details: errors,
-      source: store.source,
-    });
+    renderReactCompilerMarkers({monaco, model, details: errors});
     /**
      * N.B. that `tabSize` is a model property, not an editor property.
      * So, the tab size has to be set per model.
      */
     model.updateOptions({tabSize: 2});
-  }, [monaco, errors, store.source]);
+  }, [monaco, errors]);
 
   useEffect(() => {
     /**

compiler/apps/playground/components/Editor/Output.tsx

@@ -11,11 +11,7 @@ import {
   InformationCircleIcon,
 } from '@heroicons/react/outline';
 import MonacoEditor, {DiffEditor} from '@monaco-editor/react';
-import {
-  CompilerErrorDetail,
-  CompilerDiagnostic,
-  type CompilerError,
-} from 'babel-plugin-react-compiler';
+import {type CompilerError} from 'babel-plugin-react-compiler/src';
 import parserBabel from 'prettier/plugins/babel';
 import * as prettierPluginEstree from 'prettier/plugins/estree';
 import * as prettier from 'prettier/standalone';
@@ -48,7 +44,6 @@ export type CompilerOutput =
       kind: 'ok';
       transformOutput: CompilerTransformOutput;
       results: Map<string, Array<PrintedCompilerPipelineValue>>;
-      errors: Array<CompilerErrorDetail | CompilerDiagnostic>;
     }
   | {
       kind: 'err';
@@ -128,36 +123,10 @@ async function tabify(
       parser: transformOutput.language === 'flow' ? 'babel-flow' : 'babel-ts',
       plugins: [parserBabel, prettierPluginEstree],
     });
-
-    let output: string;
-    let language: string;
-    if (compilerOutput.errors.length === 0) {
-      output = code;
-      language = 'javascript';
-    } else {
-      language = 'markdown';
-      output = `
-# Summary
-
-React Compiler compiled this function successfully, but there are lint errors that indicate potential issues with the original code.
-
-## ${compilerOutput.errors.length} Lint Errors
-
-${compilerOutput.errors.map(e => e.printErrorMessage(source, {eslint: false})).join('\n\n')}
-
-## Output
-
-\`\`\`js
-${code}
-\`\`\`
-`.trim();
-    }
-
     reorderedTabs.set(
-      'Output',
+      'JS',
       <TextTabContent
-        output={output}
-        language={language}
+        output={code}
         diff={null}
         showInfoPanel={false}></TextTabContent>,
     );
@@ -173,18 +142,6 @@ ${code}
         </>,
       );
     }
-  } else if (compilerOutput.kind === 'err') {
-    const errors = compilerOutput.error.printErrorMessage(source, {
-      eslint: false,
-    });
-    reorderedTabs.set(
-      'Output',
-      <TextTabContent
-        output={errors}
-        language="markdown"
-        diff={null}
-        showInfoPanel={false}></TextTabContent>,
-    );
   }
   tabs.forEach((tab, name) => {
     reorderedTabs.set(name, tab);
@@ -205,32 +162,17 @@ function getSourceMapUrl(code: string, map: string): string | null {
 }
 
 function Output({store, compilerOutput}: Props): JSX.Element {
-  const [tabsOpen, setTabsOpen] = useState<Set<string>>(
-    () => new Set(['Output']),
-  );
+  const [tabsOpen, setTabsOpen] = useState<Set<string>>(() => new Set(['JS']));
   const [tabs, setTabs] = useState<Map<string, React.ReactNode>>(
     () => new Map(),
   );
-
-  /*
-   * Update the active tab back to the output or errors tab when the compilation state
-   * changes between success/failure.
-   */
-  const [previousOutputKind, setPreviousOutputKind] = useState(
-    compilerOutput.kind,
-  );
-  if (compilerOutput.kind !== previousOutputKind) {
-    setPreviousOutputKind(compilerOutput.kind);
-    setTabsOpen(new Set(['Output']));
-  }
-
   useEffect(() => {
     tabify(store.source, compilerOutput).then(tabs => {
       setTabs(tabs);
     });
   }, [store.source, compilerOutput]);
 
-  const changedPasses: Set<string> = new Set(['Output', 'HIR']); // Initial and final passes should always be bold
+  const changedPasses: Set<string> = new Set(['JS', 'HIR']); // Initial and final passes should always be bold
   let lastResult: string = '';
   for (const [passName, results] of compilerOutput.results) {
     for (const result of results) {
@@ -254,6 +196,20 @@ function Output({store, compilerOutput}: Props): JSX.Element {
         tabs={tabs}
         changedPasses={changedPasses}
       />
+      {compilerOutput.kind === 'err' ? (
+        <div
+          className="flex flex-wrap absolute bottom-0 bg-white grow border-y border-grey-200 transition-all ease-in"
+          style={{width: 'calc(100vw - 650px)'}}>
+          <div className="w-full p-4 basis-full border-b">
+            <h2>COMPILER ERRORS</h2>
+          </div>
+          <pre
+            className="p-4 basis-full text-red-600 overflow-y-scroll whitespace-pre-wrap"
+            style={{width: 'calc(100vw - 650px)', height: '150px'}}>
+            <code>{compilerOutput.error.toString()}</code>
+          </pre>
+        </div>
+      ) : null}
     </>
   );
 }
@@ -262,12 +218,10 @@ function TextTabContent({
   output,
   diff,
   showInfoPanel,
-  language,
 }: {
   output: string;
   diff: string | null;
   showInfoPanel: boolean;
-  language: string;
 }): JSX.Element {
   const [diffMode, setDiffMode] = useState(false);
   return (
@@ -318,7 +272,7 @@ function TextTabContent({
         />
       ) : (
         <MonacoEditor
-          language={language ?? 'javascript'}
+          defaultLanguage="javascript"
           value={output}
           options={{
             ...monacoOptions,

compiler/apps/playground/components/Editor/monacoOptions.ts

@@ -28,5 +28,5 @@ export const monacoOptions: Partial<EditorProps['options']> = {
 
   automaticLayout: true,
   wordWrap: 'on',
-  wrappingIndent: 'same',
+  wrappingIndent: 'deepIndent',
 };

compiler/apps/playground/lib/reactCompilerMonacoDiagnostics.ts

@@ -7,10 +7,9 @@
 
 import {Monaco} from '@monaco-editor/react';
 import {
-  CompilerDiagnostic,
   CompilerErrorDetail,
   ErrorSeverity,
-} from 'babel-plugin-react-compiler';
+} from 'babel-plugin-react-compiler/src';
 import {MarkerSeverity, type editor} from 'monaco-editor';
 
 function mapReactCompilerSeverityToMonaco(
@@ -26,46 +25,38 @@ function mapReactCompilerSeverityToMonaco(
 }
 
 function mapReactCompilerDiagnosticToMonacoMarker(
-  detail: CompilerErrorDetail | CompilerDiagnostic,
+  detail: CompilerErrorDetail,
   monaco: Monaco,
-  source: string,
 ): editor.IMarkerData | null {
-  const loc = detail.primaryLocation();
-  if (loc == null || typeof loc === 'symbol') {
+  if (detail.loc == null || typeof detail.loc === 'symbol') {
     return null;
   }
   const severity = mapReactCompilerSeverityToMonaco(detail.severity, monaco);
-  let message = detail.printErrorMessage(source, {eslint: true});
+  let message = detail.printErrorMessage();
   return {
     severity,
     message,
-    startLineNumber: loc.start.line,
-    startColumn: loc.start.column + 1,
-    endLineNumber: loc.end.line,
-    endColumn: loc.end.column + 1,
+    startLineNumber: detail.loc.start.line,
+    startColumn: detail.loc.start.column + 1,
+    endLineNumber: detail.loc.end.line,
+    endColumn: detail.loc.end.column + 1,
   };
 }
 
 type ReactCompilerMarkerConfig = {
   monaco: Monaco;
   model: editor.ITextModel;
-  details: Array<CompilerErrorDetail | CompilerDiagnostic>;
-  source: string;
+  details: Array<CompilerErrorDetail>;
 };
 let decorations: Array<string> = [];
 export function renderReactCompilerMarkers({
   monaco,
   model,
   details,
-  source,
 }: ReactCompilerMarkerConfig): void {
-  const markers: Array<editor.IMarkerData> = [];
+  let markers = [];
   for (const detail of details) {
-    const marker = mapReactCompilerDiagnosticToMonacoMarker(
-      detail,
-      monaco,
-      source,
-    );
+    const marker = mapReactCompilerDiagnosticToMonacoMarker(detail, monaco);
     if (marker == null) {
       continue;
     }

compiler/apps/playground/package.json

@@ -4,7 +4,7 @@
   "private": true,
   "scripts": {
     "dev": "cd ../.. && concurrently --kill-others -n compiler,runtime,playground \"yarn workspace babel-plugin-react-compiler run watch\" \"yarn workspace react-compiler-runtime run watch\" \"wait-on packages/babel-plugin-react-compiler/dist/index.js && cd apps/playground && NODE_ENV=development next dev\"",
-    "build:compiler": "cd ../.. && concurrently -n compiler,runtime \"yarn workspace babel-plugin-react-compiler run build --dts\" \"yarn workspace react-compiler-runtime run build\"",
+    "build:compiler": "cd ../.. && concurrently -n compiler,runtime \"yarn workspace babel-plugin-react-compiler run build\" \"yarn workspace react-compiler-runtime run build\"",
     "build": "yarn build:compiler && next build",
     "postbuild": "node ./scripts/downloadFonts.js",
     "preinstall": "cd ../.. && yarn install --frozen-lockfile",
@@ -27,7 +27,7 @@
     "@babel/types": "7.26.3",
     "@heroicons/react": "^1.0.6",
     "@monaco-editor/react": "^4.4.6",
-    "@playwright/test": "^1.51.1",
+    "@playwright/test": "^1.42.1",
     "@use-gesture/react": "^10.2.22",
     "hermes-eslint": "^0.25.0",
     "hermes-parser": "^0.25.0",

compiler/apps/playground/scripts/link-compiler.sh

@@ -8,8 +8,8 @@ set -eo pipefail
 
 HERE=$(pwd)
 
-cd ../../packages/react-compiler-runtime && yarn --silent link && cd "$HERE"
-cd ../../packages/babel-plugin-react-compiler && yarn --silent link && cd "$HERE"
+cd ../../packages/react-compiler-runtime && yarn --silent link && cd $HERE
+cd ../../packages/babel-plugin-react-compiler && yarn --silent link && cd $HERE
 
 yarn --silent link babel-plugin-react-compiler
 yarn --silent link react-compiler-runtime

compiler/apps/playground/yarn.lock

@@ -781,12 +781,12 @@
   resolved "https://registry.yarnpkg.com/@pkgjs/parseargs/-/parseargs-0.11.0.tgz#a77ea742fab25775145434eb1d2328cf5013ac33"
   integrity sha512-+1VkjdD0QBLPodGrJUeqarH8VAIvQODIbwh9XpP5Syisf7YoQgsJKPNFoqqLQlu+VQ/tVSshMR6loPMn8U+dPg==
 
-"@playwright/test@^1.51.1":
-  version "1.51.1"
-  resolved "https://registry.yarnpkg.com/@playwright/test/-/test-1.51.1.tgz#75357d513221a7be0baad75f01e966baf9c41a2e"
-  integrity sha512-nM+kEaTSAoVlXmMPH10017vn3FSiFqr/bh4fKg9vmAdMfd9SDqRZNvPSiAHADc/itWak+qPvMPZQOPwCBW7k7Q==
+"@playwright/test@^1.42.1":
+  version "1.47.2"
+  resolved "https://registry.yarnpkg.com/@playwright/test/-/test-1.47.2.tgz#dbe7051336bfc5cc599954214f9111181dbc7475"
+  integrity sha512-jTXRsoSPONAs8Za9QEQdyjFn+0ZQFjCiIztAIF6bi1HqhBzG9Ma7g1WotyiGqFSBRZjIEqMdT8RUlbk1QVhzCQ==
   dependencies:
-    playwright "1.51.1"
+    playwright "1.47.2"
 
 "@rtsao/scc@^1.1.0":
   version "1.1.0"
@@ -1249,14 +1249,14 @@ camelcase-css@^2.0.1:
   integrity sha512-QOSvevhslijgYwRx6Rv7zKdMF8lbRmx+uQGx2+vDc+KI/eBnsy9kit5aj23AgGu3pa4t9AgwbnXWqS+iOY+2aA==
 
 caniuse-lite@^1.0.30001579:
-  version "1.0.30001715"
-  resolved "https://registry.npmjs.org/caniuse-lite/-/caniuse-lite-1.0.30001715.tgz"
-  integrity sha512-7ptkFGMm2OAOgvZpwgA4yjQ5SQbrNVGdRjzH0pBdy1Fasvcr+KAeECmbCAECzTuDuoX0FCY8KzUxjf9+9kfZEw==
+  version "1.0.30001669"
+  resolved "https://registry.yarnpkg.com/caniuse-lite/-/caniuse-lite-1.0.30001669.tgz#fda8f1d29a8bfdc42de0c170d7f34a9cf19ed7a3"
+  integrity sha512-DlWzFDJqstqtIVx1zeSpIMLjunf5SmwOw0N2Ck/QSQdS8PLS4+9HrLaYei4w8BIAL7IB/UEDu889d8vhCTPA0w==
 
 caniuse-lite@^1.0.30001646, caniuse-lite@^1.0.30001663:
-  version "1.0.30001715"
-  resolved "https://registry.npmjs.org/caniuse-lite/-/caniuse-lite-1.0.30001715.tgz"
-  integrity sha512-7ptkFGMm2OAOgvZpwgA4yjQ5SQbrNVGdRjzH0pBdy1Fasvcr+KAeECmbCAECzTuDuoX0FCY8KzUxjf9+9kfZEw==
+  version "1.0.30001664"
+  resolved "https://registry.yarnpkg.com/caniuse-lite/-/caniuse-lite-1.0.30001664.tgz#d588d75c9682d3301956b05a3749652a80677df4"
+  integrity sha512-AmE7k4dXiNKQipgn7a2xg558IRqPN3jMQY/rOsbxDhrd0tyChwbITBfiwtnqz8bi2M5mIWbxAYBvk7W7QBUS2g==
 
 chalk@^2.4.2:
   version "2.4.2"
@@ -3008,17 +3008,17 @@ pirates@^4.0.1:
   resolved "https://registry.yarnpkg.com/pirates/-/pirates-4.0.6.tgz#3018ae32ecfcff6c29ba2267cbf21166ac1f36b9"
   integrity sha512-saLsH7WeYYPiD25LDuLRRY/i+6HaPYr6G1OUlN39otzkSTxKnubR9RTxS3/Kk50s1g2JTgFwWQDQyplC5/SHZg==
 
-playwright-core@1.51.1:
-  version "1.51.1"
-  resolved "https://registry.yarnpkg.com/playwright-core/-/playwright-core-1.51.1.tgz#d57f0393e02416f32a47cf82b27533656a8acce1"
-  integrity sha512-/crRMj8+j/Nq5s8QcvegseuyeZPxpQCZb6HNk3Sos3BlZyAknRjoyJPFWkpNn8v0+P3WiwqFF8P+zQo4eqiNuw==
+playwright-core@1.47.2:
+  version "1.47.2"
+  resolved "https://registry.yarnpkg.com/playwright-core/-/playwright-core-1.47.2.tgz#7858da9377fa32a08be46ba47d7523dbd9460a4e"
+  integrity sha512-3JvMfF+9LJfe16l7AbSmU555PaTl2tPyQsVInqm3id16pdDfvZ8TTZ/pyzmkbDrZTQefyzU7AIHlZqQnxpqHVQ==
 
-playwright@1.51.1:
-  version "1.51.1"
-  resolved "https://registry.yarnpkg.com/playwright/-/playwright-1.51.1.tgz#ae1467ee318083968ad28d6990db59f47a55390f"
-  integrity sha512-kkx+MB2KQRkyxjYPc3a0wLZZoDczmppyGJIvQ43l+aZihkaVvmu/21kiyaHeHjiFxjxNNFnUncKmcGIyOojsaw==
+playwright@1.47.2:
+  version "1.47.2"
+  resolved "https://registry.yarnpkg.com/playwright/-/playwright-1.47.2.tgz#155688aa06491ee21fb3e7555b748b525f86eb20"
+  integrity sha512-nx1cLMmQWqmA3UsnjaaokyoUpdVaaDhJhMoxX2qj3McpjnsqFHs516QAKYhqHAgOP+oCFTEOCOAaD1RgD/RQfA==
   dependencies:
-    playwright-core "1.51.1"
+    playwright-core "1.47.2"
   optionalDependencies:
     fsevents "2.3.2"
 

compiler/package.json

@@ -37,7 +37,7 @@
     "prettier": "^3.3.3",
     "prettier-plugin-hermes-parser": "^0.26.0",
     "prompt-promise": "^1.0.3",
-    "rimraf": "^6.0.1",
+    "rimraf": "^5.0.10",
     "to-fast-properties": "^2.0.0",
     "tsup": "^8.4.0",
     "typescript": "^5.4.3",
@@ -45,6 +45,7 @@
     "yargs": "^17.7.2"
   },
   "resolutions": {
+    "rimraf": "5.0.10",
     "@babel/types": "7.26.3"
   },
   "packageManager": "yarn@1.22.22"

compiler/packages/babel-plugin-react-compiler/package.json

@@ -12,12 +12,12 @@
     "build": "rimraf dist && tsup",
     "test": "./scripts/link-react-compiler-runtime.sh && yarn snap:ci",
     "jest": "yarn build && ts-node node_modules/.bin/jest",
-    "snap": "yarn workspace snap run snap",
+    "snap": "node ../snap/dist/main.js",
     "snap:build": "yarn workspace snap run build",
     "snap:ci": "yarn snap:build && yarn snap",
     "ts:analyze-trace": "scripts/ts-analyze-trace.sh",
     "lint": "yarn eslint src",
-    "watch": "yarn build --dts --watch"
+    "watch": "yarn build --watch"
   },
   "dependencies": {
     "@babel/types": "^7.26.0"

compiler/packages/babel-plugin-react-compiler/scripts/jest/e2e-forget.config.js

@@ -7,4 +7,7 @@
 
 const makeE2EConfig = require('../jest/makeE2EConfig');
 
-module.exports = makeE2EConfig('e2e with forget', true);
+const config = makeE2EConfig('e2e with forget', true);
+config.setupFilesAfterEnv = ['<rootDir>/../scripts/jest/setupEnvE2E.js'];
+
+module.exports = config;

compiler/packages/babel-plugin-react-compiler/scripts/jest/makeTransform.ts

@@ -5,16 +5,19 @@
  * LICENSE file in the root directory of this source tree.
  */
 
+import {jsx} from '@babel/plugin-syntax-jsx';
 import babelJest from 'babel-jest';
-import {
-  validateEnvironmentConfig,
-  EnvironmentConfig,
-} from 'babel-plugin-react-compiler';
+import {compile} from 'babel-plugin-react-compiler';
 import {execSync} from 'child_process';
 
 import type {NodePath, Visitor} from '@babel/traverse';
-import type {CallExpression} from '@babel/types';
-import BabelPluginReactCompiler from 'babel-plugin-react-compiler';
+import type {CallExpression, FunctionDeclaration} from '@babel/types';
+import * as t from '@babel/types';
+import {
+  EnvironmentConfig,
+  validateEnvironmentConfig,
+} from 'babel-plugin-react-compiler';
+import {basename} from 'path';
 
 /**
  * -- IMPORTANT --
@@ -25,19 +28,10 @@ import BabelPluginReactCompiler from 'babel-plugin-react-compiler';
 const e2eTransformerCacheKey = 1;
 const forgetOptions: EnvironmentConfig = validateEnvironmentConfig({
   enableAssumeHooksFollowRulesOfReact: true,
+  enableFunctionOutlining: false,
 });
 const debugMode = process.env['DEBUG_FORGET_COMPILER'] != null;
 
-const compilerCacheKey = execSync(
-  'yarn --silent --cwd ../.. hash packages/babel-plugin-react-compiler/dist',
-)
-  .toString()
-  .trim();
-
-if (debugMode) {
-  console.log('cachebreaker', compilerCacheKey);
-}
-
 module.exports = (useForget: boolean) => {
   function createTransformer() {
     return babelJest.createTransformer({
@@ -48,14 +42,15 @@ module.exports = (useForget: boolean) => {
           plugins: [
             useForget
               ? [
-                  BabelPluginReactCompiler,
+                  ReactForgetFunctionTransform,
                   {
-                    environment: forgetOptions,
                     /*
                      * Jest hashes the babel config as a cache breaker.
                      * (see https://github.com/jestjs/jest/blob/v29.6.2/packages/babel-jest/src/index.ts#L84)
                      */
-                    compilerCacheKey,
+                    compilerCacheKey: execSync(
+                      'yarn --silent --cwd ../.. hash packages/babel-plugin-react-compiler/dist',
+                    ).toString(),
                     transformOptionsCacheKey: forgetOptions,
                     e2eTransformerCacheKey,
                   },
@@ -110,3 +105,103 @@ module.exports = (useForget: boolean) => {
     createTransformer,
   };
 };
+
+// Mostly copied from react/scripts/babel/transform-forget.js
+function isReactComponentLike(fn: NodePath<FunctionDeclaration>): boolean {
+  let isReactComponent = false;
+  let hasNoUseForgetDirective = false;
+
+  /*
+   * React components start with an upper case letter,
+   * React hooks start with `use`
+   */
+  if (
+    fn.node.id == null ||
+    (fn.node.id.name[0].toUpperCase() !== fn.node.id.name[0] &&
+      !/^use[A-Z0-9]/.test(fn.node.id.name))
+  ) {
+    return false;
+  }
+
+  fn.traverse({
+    DirectiveLiteral(path) {
+      if (path.node.value === 'use no forget') {
+        hasNoUseForgetDirective = true;
+      }
+    },
+
+    JSX(path) {
+      // Is there is a JSX node created in the current function context?
+      if (path.scope.getFunctionParent()?.path.node === fn.node) {
+        isReactComponent = true;
+      }
+    },
+
+    CallExpression(path) {
+      // Is there hook usage?
+      if (
+        path.node.callee.type === 'Identifier' &&
+        !/^use[A-Z0-9]/.test(path.node.callee.name)
+      ) {
+        isReactComponent = true;
+      }
+    },
+  });
+
+  if (hasNoUseForgetDirective) {
+    return false;
+  }
+
+  return isReactComponent;
+}
+
+function ReactForgetFunctionTransform() {
+  const compiledFns = new Set();
+  const visitor = {
+    FunctionDeclaration(fn: NodePath<FunctionDeclaration>, state: any): void {
+      if (compiledFns.has(fn.node)) {
+        return;
+      }
+
+      if (!isReactComponentLike(fn)) {
+        return;
+      }
+      if (debugMode) {
+        const filename = basename(state.file.opts.filename);
+        if (fn.node.loc && fn.node.id) {
+          console.log(
+            ` Compiling ${filename}:${fn.node.loc.start.line}:${fn.node.loc.start.column}  ${fn.node.id.name}`,
+          );
+        } else {
+          console.log(` Compiling ${filename} ${fn.node.id?.name}`);
+        }
+      }
+
+      const compiled = compile(
+        fn,
+        forgetOptions,
+        'Other',
+        '_c',
+        null,
+        null,
+        null,
+      );
+      compiledFns.add(compiled);
+
+      const fun = t.functionDeclaration(
+        compiled.id,
+        compiled.params,
+        compiled.body,
+        compiled.generator,
+        compiled.async,
+      );
+      fn.replaceWith(fun);
+      fn.skip();
+    },
+  };
+  return {
+    name: 'react-forget-e2e',
+    inherits: jsx,
+    visitor,
+  };
+}

compiler/packages/babel-plugin-react-compiler/scripts/jest/setupEnvE2E.js

@@ -0,0 +1,16 @@
+/**
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+const ReactCompilerRuntime = require('react/compiler-runtime');
+
+/*
+ * Our e2e babel transform currently only compiles functions, not programs.
+ * As a result, our e2e transpiled code does not contain an import for the
+ * memo cache function. As a temporary hack, we add a `_c` global, which is
+ * the name that is used for the import by default.
+ */
+globalThis._c = ReactCompilerRuntime.c;

compiler/packages/babel-plugin-react-compiler/src/Babel/BabelPlugin.ts

@@ -11,8 +11,6 @@ import {
   injectReanimatedFlag,
   pipelineUsesReanimatedPlugin,
 } from '../Entrypoint/Reanimated';
-import validateNoUntransformedReferences from '../Entrypoint/ValidateNoUntransformedReferences';
-import {CompilerError} from '..';
 
 const ENABLE_REACT_COMPILER_TIMINGS =
   process.env['ENABLE_REACT_COMPILER_TIMINGS'] === '1';
@@ -35,58 +33,44 @@ export default function BabelPluginReactCompiler(
        */
       Program: {
         enter(prog, pass): void {
-          try {
-            const filename = pass.filename ?? 'unknown';
-            if (ENABLE_REACT_COMPILER_TIMINGS === true) {
-              performance.mark(`${filename}:start`, {
-                detail: 'BabelPlugin:Program:start',
-              });
-            }
-            let opts = parsePluginOptions(pass.opts);
-            const isDev =
-              (typeof __DEV__ !== 'undefined' && __DEV__ === true) ||
-              process.env['NODE_ENV'] === 'development';
-            if (
-              opts.enableReanimatedCheck === true &&
-              pipelineUsesReanimatedPlugin(pass.file.opts.plugins)
-            ) {
-              opts = injectReanimatedFlag(opts);
-            }
-            if (
-              opts.environment.enableResetCacheOnSourceFileChanges !== false &&
-              isDev
-            ) {
-              opts = {
-                ...opts,
-                environment: {
-                  ...opts.environment,
-                  enableResetCacheOnSourceFileChanges: true,
-                },
-              };
-            }
-            const result = compileProgram(prog, {
-              opts,
-              filename: pass.filename ?? null,
-              comments: pass.file.ast.comments ?? [],
-              code: pass.file.code,
+          const filename = pass.filename ?? 'unknown';
+          if (ENABLE_REACT_COMPILER_TIMINGS === true) {
+            performance.mark(`${filename}:start`, {
+              detail: 'BabelPlugin:Program:start',
+            });
+          }
+          let opts = parsePluginOptions(pass.opts);
+          const isDev =
+            (typeof __DEV__ !== 'undefined' && __DEV__ === true) ||
+            process.env['NODE_ENV'] === 'development';
+          if (
+            opts.enableReanimatedCheck === true &&
+            pipelineUsesReanimatedPlugin(pass.file.opts.plugins)
+          ) {
+            opts = injectReanimatedFlag(opts);
+          }
+          if (
+            opts.environment.enableResetCacheOnSourceFileChanges !== false &&
+            isDev
+          ) {
+            opts = {
+              ...opts,
+              environment: {
+                ...opts.environment,
+                enableResetCacheOnSourceFileChanges: true,
+              },
+            };
+          }
+          compileProgram(prog, {
+            opts,
+            filename: pass.filename ?? null,
+            comments: pass.file.ast.comments ?? [],
+            code: pass.file.code,
+          });
+          if (ENABLE_REACT_COMPILER_TIMINGS === true) {
+            performance.mark(`${filename}:end`, {
+              detail: 'BabelPlugin:Program:end',
             });
-            validateNoUntransformedReferences(
-              prog,
-              pass.filename ?? null,
-              opts.logger,
-              opts.environment,
-              result,
-            );
-            if (ENABLE_REACT_COMPILER_TIMINGS === true) {
-              performance.mark(`${filename}:end`, {
-                detail: 'BabelPlugin:Program:end',
-              });
-            }
-          } catch (e) {
-            if (e instanceof CompilerError) {
-              throw e.withPrintedMessage(pass.file.code, {eslint: false});
-            }
-            throw e;
           }
         },
         exit(_, pass): void {

compiler/packages/babel-plugin-react-compiler/src/CompilerError.ts

@@ -5,10 +5,7 @@
  * LICENSE file in the root directory of this source tree.
  */
 
-import * as t from '@babel/types';
-import {codeFrameColumns} from '@babel/code-frame';
 import type {SourceLocation} from './HIR';
-import {Err, Ok, Result} from './Utils/Result';
 import {assertExhaustive} from './Utils/utils';
 
 export enum ErrorSeverity {
@@ -17,11 +14,6 @@ export enum ErrorSeverity {
    * misunderstanding on the user’s part.
    */
   InvalidJS = 'InvalidJS',
-  /**
-   * JS syntax that is not supported and which we do not plan to support. Developers should
-   * rewrite to use supported forms.
-   */
-  UnsupportedJS = 'UnsupportedJS',
   /**
    * Code that breaks the rules of React.
    */
@@ -46,24 +38,6 @@ export enum ErrorSeverity {
   Invariant = 'Invariant',
 }
 
-export type CompilerDiagnosticOptions = {
-  severity: ErrorSeverity;
-  category: string;
-  description: string;
-  details: Array<CompilerDiagnosticDetail>;
-  suggestions?: Array<CompilerSuggestion> | null | undefined;
-};
-
-export type CompilerDiagnosticDetail =
-  /**
-   * A/the source of the error
-   */
-  {
-    kind: 'error';
-    loc: SourceLocation | null;
-    message: string;
-  };
-
 export enum CompilerSuggestionOperation {
   InsertBefore,
   InsertAfter,
@@ -94,103 +68,6 @@ export type CompilerErrorDetailOptions = {
   suggestions?: Array<CompilerSuggestion> | null | undefined;
 };
 
-export type PrintErrorMessageOptions = {
-  /**
-   * ESLint uses 1-indexed columns and prints one error at a time
-   * So it doesn't require the "Found # error(s)" text
-   */
-  eslint: boolean;
-};
-
-export class CompilerDiagnostic {
-  options: CompilerDiagnosticOptions;
-
-  constructor(options: CompilerDiagnosticOptions) {
-    this.options = options;
-  }
-
-  static create(
-    options: Omit<CompilerDiagnosticOptions, 'details'>,
-  ): CompilerDiagnostic {
-    return new CompilerDiagnostic({...options, details: []});
-  }
-
-  get category(): CompilerDiagnosticOptions['category'] {
-    return this.options.category;
-  }
-  get description(): CompilerDiagnosticOptions['description'] {
-    return this.options.description;
-  }
-  get severity(): CompilerDiagnosticOptions['severity'] {
-    return this.options.severity;
-  }
-  get suggestions(): CompilerDiagnosticOptions['suggestions'] {
-    return this.options.suggestions;
-  }
-
-  withDetail(detail: CompilerDiagnosticDetail): CompilerDiagnostic {
-    this.options.details.push(detail);
-    return this;
-  }
-
-  primaryLocation(): SourceLocation | null {
-    return this.options.details.filter(d => d.kind === 'error')[0]?.loc ?? null;
-  }
-
-  printErrorMessage(source: string, options: PrintErrorMessageOptions): string {
-    const buffer = [
-      printErrorSummary(this.severity, this.category),
-      '\n\n',
-      this.description,
-    ];
-    for (const detail of this.options.details) {
-      switch (detail.kind) {
-        case 'error': {
-          const loc = detail.loc;
-          if (loc == null || typeof loc === 'symbol') {
-            continue;
-          }
-          let codeFrame: string;
-          try {
-            codeFrame = printCodeFrame(source, loc, detail.message);
-          } catch (e) {
-            codeFrame = detail.message;
-          }
-          buffer.push('\n\n');
-          if (loc.filename != null) {
-            const line = loc.start.line;
-            const column = options.eslint
-              ? loc.start.column + 1
-              : loc.start.column;
-            buffer.push(`${loc.filename}:${line}:${column}\n`);
-          }
-          buffer.push(codeFrame);
-          break;
-        }
-        default: {
-          assertExhaustive(
-            detail.kind,
-            `Unexpected detail kind ${(detail as any).kind}`,
-          );
-        }
-      }
-    }
-    return buffer.join('');
-  }
-
-  toString(): string {
-    const buffer = [printErrorSummary(this.severity, this.category)];
-    if (this.description != null) {
-      buffer.push(`. ${this.description}.`);
-    }
-    const loc = this.primaryLocation();
-    if (loc != null && typeof loc !== 'symbol') {
-      buffer.push(` (${loc.start.line}:${loc.start.column})`);
-    }
-    return buffer.join('');
-  }
-}
-
 /*
  * Each bailout or invariant in HIR lowering creates an {@link CompilerErrorDetail}, which is then
  * aggregated into a single {@link CompilerError} later.
@@ -218,51 +95,24 @@ export class CompilerErrorDetail {
     return this.options.suggestions;
   }
 
-  primaryLocation(): SourceLocation | null {
-    return this.loc;
-  }
-
-  printErrorMessage(source: string, options: PrintErrorMessageOptions): string {
-    const buffer = [printErrorSummary(this.severity, this.reason)];
+  printErrorMessage(): string {
+    const buffer = [`${this.severity}: ${this.reason}`];
     if (this.description != null) {
-      buffer.push(`\n\n${this.description}.`);
+      buffer.push(`. ${this.description}`);
     }
-    const loc = this.loc;
-    if (loc != null && typeof loc !== 'symbol') {
-      let codeFrame: string;
-      try {
-        codeFrame = printCodeFrame(source, loc, this.reason);
-      } catch (e) {
-        codeFrame = '';
-      }
-      buffer.push(`\n\n`);
-      if (loc.filename != null) {
-        const line = loc.start.line;
-        const column = options.eslint ? loc.start.column + 1 : loc.start.column;
-        buffer.push(`${loc.filename}:${line}:${column}\n`);
-      }
-      buffer.push(codeFrame);
-      buffer.push('\n\n');
+    if (this.loc != null && typeof this.loc !== 'symbol') {
+      buffer.push(` (${this.loc.start.line}:${this.loc.end.line})`);
     }
     return buffer.join('');
   }
 
   toString(): string {
-    const buffer = [printErrorSummary(this.severity, this.reason)];
-    if (this.description != null) {
-      buffer.push(`. ${this.description}.`);
-    }
-    const loc = this.loc;
-    if (loc != null && typeof loc !== 'symbol') {
-      buffer.push(` (${loc.start.line}:${loc.start.column})`);
-    }
-    return buffer.join('');
+    return this.printErrorMessage();
   }
 }
 
 export class CompilerError extends Error {
-  details: Array<CompilerErrorDetail | CompilerDiagnostic> = [];
-  printedMessage: string | null = null;
+  details: Array<CompilerErrorDetail> = [];
 
   static invariant(
     condition: unknown,
@@ -280,12 +130,6 @@ export class CompilerError extends Error {
     }
   }
 
-  static throwDiagnostic(options: CompilerDiagnosticOptions): never {
-    const errors = new CompilerError();
-    errors.pushDiagnostic(new CompilerDiagnostic(options));
-    throw errors;
-  }
-
   static throwTodo(
     options: Omit<CompilerErrorDetailOptions, 'severity'>,
   ): never {
@@ -348,49 +192,18 @@ export class CompilerError extends Error {
   }
 
   override get message(): string {
-    return this.printedMessage ?? this.toString();
+    return this.toString();
   }
 
   override set message(_message: string) {}
 
   override toString(): string {
-    if (this.printedMessage) {
-      return this.printedMessage;
-    }
     if (Array.isArray(this.details)) {
       return this.details.map(detail => detail.toString()).join('\n\n');
     }
     return this.name;
   }
 
-  withPrintedMessage(
-    source: string,
-    options: PrintErrorMessageOptions,
-  ): CompilerError {
-    this.printedMessage = this.printErrorMessage(source, options);
-    return this;
-  }
-
-  printErrorMessage(source: string, options: PrintErrorMessageOptions): string {
-    if (options.eslint && this.details.length === 1) {
-      return this.details[0].printErrorMessage(source, options);
-    }
-    return (
-      `Found ${this.details.length} error${this.details.length === 1 ? '' : 's'}:\n\n` +
-      this.details
-        .map(detail => detail.printErrorMessage(source, options).trim())
-        .join('\n\n')
-    );
-  }
-
-  merge(other: CompilerError): void {
-    this.details.push(...other.details);
-  }
-
-  pushDiagnostic(diagnostic: CompilerDiagnostic): void {
-    this.details.push(diagnostic);
-  }
-
   push(options: CompilerErrorDetailOptions): CompilerErrorDetail {
     const detail = new CompilerErrorDetail({
       reason: options.reason,
@@ -411,10 +224,6 @@ export class CompilerError extends Error {
     return this.details.length > 0;
   }
 
-  asResult(): Result<void, CompilerError> {
-    return this.hasErrors() ? Err(this) : Ok(undefined);
-  }
-
   /*
    * An error is critical if it means the compiler has entered into a broken state and cannot
    * continue safely. Other expected errors such as Todos mean that we can skip over that component
@@ -427,69 +236,13 @@ export class CompilerError extends Error {
         case ErrorSeverity.InvalidJS:
         case ErrorSeverity.InvalidReact:
         case ErrorSeverity.InvalidConfig:
-        case ErrorSeverity.UnsupportedJS: {
           return true;
-        }
         case ErrorSeverity.CannotPreserveMemoization:
-        case ErrorSeverity.Todo: {
+        case ErrorSeverity.Todo:
           return false;
-        }
-        default: {
+        default:
           assertExhaustive(detail.severity, 'Unhandled error severity');
-        }
       }
     });
   }
 }
-
-function printCodeFrame(
-  source: string,
-  loc: t.SourceLocation,
-  message: string,
-): string {
-  return codeFrameColumns(
-    source,
-    {
-      start: {
-        line: loc.start.line,
-        column: loc.start.column + 1,
-      },
-      end: {
-        line: loc.end.line,
-        column: loc.end.column + 1,
-      },
-    },
-    {
-      message,
-    },
-  );
-}
-
-function printErrorSummary(severity: ErrorSeverity, message: string): string {
-  let severityCategory: string;
-  switch (severity) {
-    case ErrorSeverity.InvalidConfig:
-    case ErrorSeverity.InvalidJS:
-    case ErrorSeverity.InvalidReact:
-    case ErrorSeverity.UnsupportedJS: {
-      severityCategory = 'Error';
-      break;
-    }
-    case ErrorSeverity.CannotPreserveMemoization: {
-      severityCategory = 'Memoization';
-      break;
-    }
-    case ErrorSeverity.Invariant: {
-      severityCategory = 'Invariant';
-      break;
-    }
-    case ErrorSeverity.Todo: {
-      severityCategory = 'Todo';
-      break;
-    }
-    default: {
-      assertExhaustive(severity, `Unexpected severity '${severity}'`);
-    }
-  }
-  return `${severityCategory}: ${message}`;
-}

compiler/packages/babel-plugin-react-compiler/src/Entrypoint/Gating.ts

@@ -7,122 +7,8 @@
 
 import {NodePath} from '@babel/core';
 import * as t from '@babel/types';
-import {CompilerError} from '../CompilerError';
-import {ProgramContext} from './Imports';
-import {ExternalFunction} from '..';
+import {PluginOptions} from './Options';
 
-/**
- * Gating rewrite for function declarations which are referenced before their
- * declaration site.
- *
- * ```js
- * // original
- * export default React.memo(Foo);
- * function Foo() { ... }
- *
- * // React compiler optimized + gated
- * import {gating} from 'myGating';
- * export default React.memo(Foo);
- * const gating_result = gating();  <- inserted
- * function Foo_optimized() {}      <- inserted
- * function Foo_unoptimized() {}    <- renamed from Foo
- * function Foo() {                 <- inserted function, which can be hoisted by JS engines
- *   if (gating_result) return Foo_optimized();
- *   else return Foo_unoptimized();
- * }
- * ```
- */
-function insertAdditionalFunctionDeclaration(
-  fnPath: NodePath<t.FunctionDeclaration>,
-  compiled: t.FunctionDeclaration,
-  programContext: ProgramContext,
-  gatingFunctionIdentifierName: string,
-): void {
-  const originalFnName = fnPath.node.id;
-  const originalFnParams = fnPath.node.params;
-  const compiledParams = fnPath.node.params;
-  /**
-   * Note that other than `export default function() {}`, all other function
-   * declarations must have a binding identifier. Since default exports cannot
-   * be referenced, it's safe to assume that all function declarations passed
-   * here will have an identifier.
-   * https://tc39.es/ecma262/multipage/ecmascript-language-functions-and-classes.html#sec-function-definitions
-   */
-  CompilerError.invariant(originalFnName != null && compiled.id != null, {
-    reason:
-      'Expected function declarations that are referenced elsewhere to have a named identifier',
-    loc: fnPath.node.loc ?? null,
-  });
-  CompilerError.invariant(originalFnParams.length === compiledParams.length, {
-    reason:
-      'Expected React Compiler optimized function declarations to have the same number of parameters as source',
-    loc: fnPath.node.loc ?? null,
-  });
-
-  const gatingCondition = t.identifier(
-    programContext.newUid(`${gatingFunctionIdentifierName}_result`),
-  );
-  const unoptimizedFnName = t.identifier(
-    programContext.newUid(`${originalFnName.name}_unoptimized`),
-  );
-  const optimizedFnName = t.identifier(
-    programContext.newUid(`${originalFnName.name}_optimized`),
-  );
-  /**
-   * Step 1: rename existing functions
-   */
-  compiled.id.name = optimizedFnName.name;
-  fnPath.get('id').replaceInline(unoptimizedFnName);
-
-  /**
-   * Step 2: insert new function declaration
-   */
-  const newParams: Array<t.Identifier | t.RestElement> = [];
-  const genNewArgs: Array<() => t.Identifier | t.SpreadElement> = [];
-  for (let i = 0; i < originalFnParams.length; i++) {
-    const argName = `arg${i}`;
-    if (originalFnParams[i].type === 'RestElement') {
-      newParams.push(t.restElement(t.identifier(argName)));
-      genNewArgs.push(() => t.spreadElement(t.identifier(argName)));
-    } else {
-      newParams.push(t.identifier(argName));
-      genNewArgs.push(() => t.identifier(argName));
-    }
-  }
-  // insertAfter called in reverse order of how nodes should appear in program
-  fnPath.insertAfter(
-    t.functionDeclaration(
-      originalFnName,
-      newParams,
-      t.blockStatement([
-        t.ifStatement(
-          gatingCondition,
-          t.returnStatement(
-            t.callExpression(
-              compiled.id,
-              genNewArgs.map(fn => fn()),
-            ),
-          ),
-          t.returnStatement(
-            t.callExpression(
-              unoptimizedFnName,
-              genNewArgs.map(fn => fn()),
-            ),
-          ),
-        ),
-      ]),
-    ),
-  );
-  fnPath.insertBefore(
-    t.variableDeclaration('const', [
-      t.variableDeclarator(
-        gatingCondition,
-        t.callExpression(t.identifier(gatingFunctionIdentifierName), []),
-      ),
-    ]),
-  );
-  fnPath.insertBefore(compiled);
-}
 export function insertGatedFunctionDeclaration(
   fnPath: NodePath<
     t.FunctionDeclaration | t.ArrowFunctionExpression | t.FunctionExpression
@@ -131,65 +17,48 @@ export function insertGatedFunctionDeclaration(
     | t.FunctionDeclaration
     | t.ArrowFunctionExpression
     | t.FunctionExpression,
-  programContext: ProgramContext,
-  gating: ExternalFunction,
-  referencedBeforeDeclaration: boolean,
+  gating: NonNullable<PluginOptions['gating']>,
 ): void {
-  const gatingImportedName = programContext.addImportSpecifier(gating).name;
-  if (referencedBeforeDeclaration && fnPath.isFunctionDeclaration()) {
-    CompilerError.invariant(compiled.type === 'FunctionDeclaration', {
-      reason: 'Expected compiled node type to match input type',
-      description: `Got ${compiled.type} but expected FunctionDeclaration`,
-      loc: fnPath.node.loc ?? null,
-    });
-    insertAdditionalFunctionDeclaration(
-      fnPath,
-      compiled,
-      programContext,
-      gatingImportedName,
+  const gatingExpression = t.conditionalExpression(
+    t.callExpression(t.identifier(gating.importSpecifierName), []),
+    buildFunctionExpression(compiled),
+    buildFunctionExpression(fnPath.node),
+  );
+
+  /*
+   * Convert function declarations to named variables *unless* this is an
+   * `export default function ...` since `export default const ...` is
+   * not supported. For that case we fall through to replacing w the raw
+   * conditional expression
+   */
+  if (
+    fnPath.parentPath.node.type !== 'ExportDefaultDeclaration' &&
+    fnPath.node.type === 'FunctionDeclaration' &&
+    fnPath.node.id != null
+  ) {
+    fnPath.replaceWith(
+      t.variableDeclaration('const', [
+        t.variableDeclarator(fnPath.node.id, gatingExpression),
+      ]),
+    );
+  } else if (
+    fnPath.parentPath.node.type === 'ExportDefaultDeclaration' &&
+    fnPath.node.type !== 'ArrowFunctionExpression' &&
+    fnPath.node.id != null
+  ) {
+    fnPath.insertAfter(
+      t.exportDefaultDeclaration(t.identifier(fnPath.node.id.name)),
+    );
+    fnPath.parentPath.replaceWith(
+      t.variableDeclaration('const', [
+        t.variableDeclarator(
+          t.identifier(fnPath.node.id.name),
+          gatingExpression,
+        ),
+      ]),
     );
   } else {
-    const gatingExpression = t.conditionalExpression(
-      t.callExpression(t.identifier(gatingImportedName), []),
-      buildFunctionExpression(compiled),
-      buildFunctionExpression(fnPath.node),
-    );
-
-    /*
-     * Convert function declarations to named variables *unless* this is an
-     * `export default function ...` since `export default const ...` is
-     * not supported. For that case we fall through to replacing w the raw
-     * conditional expression
-     */
-    if (
-      fnPath.parentPath.node.type !== 'ExportDefaultDeclaration' &&
-      fnPath.node.type === 'FunctionDeclaration' &&
-      fnPath.node.id != null
-    ) {
-      fnPath.replaceWith(
-        t.variableDeclaration('const', [
-          t.variableDeclarator(fnPath.node.id, gatingExpression),
-        ]),
-      );
-    } else if (
-      fnPath.parentPath.node.type === 'ExportDefaultDeclaration' &&
-      fnPath.node.type !== 'ArrowFunctionExpression' &&
-      fnPath.node.id != null
-    ) {
-      fnPath.insertAfter(
-        t.exportDefaultDeclaration(t.identifier(fnPath.node.id.name)),
-      );
-      fnPath.parentPath.replaceWith(
-        t.variableDeclaration('const', [
-          t.variableDeclarator(
-            t.identifier(fnPath.node.id.name),
-            gatingExpression,
-          ),
-        ]),
-      );
-    } else {
-      fnPath.replaceWith(gatingExpression);
-    }
+    fnPath.replaceWith(gatingExpression);
   }
 }
 

compiler/packages/babel-plugin-react-compiler/src/Entrypoint/Imports.ts

@@ -7,20 +7,9 @@
 
 import {NodePath} from '@babel/core';
 import * as t from '@babel/types';
-import {Scope as BabelScope} from '@babel/traverse';
-
 import {CompilerError, ErrorSeverity} from '../CompilerError';
-import {
-  EnvironmentConfig,
-  GeneratedSource,
-  NonLocalImportSpecifier,
-} from '../HIR';
-import {getOrInsertWith} from '../Utils/utils';
-import {ExternalFunction, isHookName} from '../HIR/Environment';
-import {Err, Ok, Result} from '../Utils/Result';
-import {LoggerEvent, PluginOptions} from './Options';
-import {BabelFn, getReactCompilerRuntimeModule} from './Program';
-import {SuppressionRange} from './Suppression';
+import {EnvironmentConfig, ExternalFunction, GeneratedSource} from '../HIR';
+import {getOrInsertDefault} from '../Utils/utils';
 
 export function validateRestrictedImports(
   path: NodePath<t.Program>,
@@ -53,248 +42,50 @@ export function validateRestrictedImports(
   }
 }
 
-type ProgramContextOptions = {
-  program: NodePath<t.Program>;
-  suppressions: Array<SuppressionRange>;
-  opts: PluginOptions;
-  filename: string | null;
-  code: string | null;
-  hasModuleScopeOptOut: boolean;
-};
-export class ProgramContext {
-  /**
-   * Program and environment context
-   */
-  scope: BabelScope;
-  opts: PluginOptions;
-  filename: string | null;
-  code: string | null;
-  reactRuntimeModule: string;
-  suppressions: Array<SuppressionRange>;
-  hasModuleScopeOptOut: boolean;
-
-  /*
-   * This is a hack to work around what seems to be a Babel bug. Babel doesn't
-   * consistently respect the `skip()` function to avoid revisiting a node within
-   * a pass, so we use this set to track nodes that we have compiled.
-   */
-  alreadyCompiled: WeakSet<object> | Set<object> = new (WeakSet ?? Set)();
-  // known generated or referenced identifiers in the program
-  knownReferencedNames: Set<string> = new Set();
-  // generated imports
-  imports: Map<string, Map<string, NonLocalImportSpecifier>> = new Map();
-
-  /**
-   * Metadata from compilation
-   */
-  retryErrors: Array<{fn: BabelFn; error: CompilerError}> = [];
-  inferredEffectLocations: Set<t.SourceLocation> = new Set();
-
-  constructor({
-    program,
-    suppressions,
-    opts,
-    filename,
-    code,
-    hasModuleScopeOptOut,
-  }: ProgramContextOptions) {
-    this.scope = program.scope;
-    this.opts = opts;
-    this.filename = filename;
-    this.code = code;
-    this.reactRuntimeModule = getReactCompilerRuntimeModule(opts.target);
-    this.suppressions = suppressions;
-    this.hasModuleScopeOptOut = hasModuleScopeOptOut;
-  }
-
-  isHookName(name: string): boolean {
-    if (this.opts.environment.hookPattern == null) {
-      return isHookName(name);
-    } else {
-      const match = new RegExp(this.opts.environment.hookPattern).exec(name);
-      return (
-        match != null && typeof match[1] === 'string' && isHookName(match[1])
-      );
-    }
-  }
-
-  hasReference(name: string): boolean {
-    return (
-      this.knownReferencedNames.has(name) ||
-      this.scope.hasBinding(name) ||
-      this.scope.hasGlobal(name) ||
-      this.scope.hasReference(name)
-    );
-  }
-
-  newUid(name: string): string {
-    /**
-     * Don't call babel's generateUid for known hook imports, as
-     * InferTypes might eventually type `HookKind` based on callee naming
-     * convention and `_useFoo` is not named as a hook.
-     *
-     * Local uid generation is susceptible to check-before-use bugs since we're
-     * checking for naming conflicts / references long before we actually insert
-     * the import. (see similar logic in HIRBuilder:resolveBinding)
-     */
-    let uid;
-    if (this.isHookName(name)) {
-      uid = name;
-      let i = 0;
-      while (this.hasReference(uid)) {
-        this.knownReferencedNames.add(uid);
-        uid = `${name}_${i++}`;
-      }
-    } else if (!this.hasReference(name)) {
-      uid = name;
-    } else {
-      uid = this.scope.generateUid(name);
-    }
-    this.knownReferencedNames.add(uid);
-    return uid;
-  }
-
-  addMemoCacheImport(): NonLocalImportSpecifier {
-    return this.addImportSpecifier(
-      {
-        source: this.reactRuntimeModule,
-        importSpecifierName: 'c',
-      },
-      '_c',
-    );
-  }
-
-  /**
-   *
-   * @param externalFunction
-   * @param nameHint if defined, will be used as the name of the import specifier
-   * @returns
-   */
-  addImportSpecifier(
-    {source: module, importSpecifierName: specifier}: ExternalFunction,
-    nameHint?: string,
-  ): NonLocalImportSpecifier {
-    const maybeBinding = this.imports.get(module)?.get(specifier);
-    if (maybeBinding != null) {
-      return {...maybeBinding};
-    }
-
-    const binding: NonLocalImportSpecifier = {
-      kind: 'ImportSpecifier',
-      name: this.newUid(nameHint ?? specifier),
-      module,
-      imported: specifier,
-    };
-    getOrInsertWith(this.imports, module, () => new Map()).set(specifier, {
-      ...binding,
-    });
-    return binding;
-  }
-
-  addNewReference(name: string): void {
-    this.knownReferencedNames.add(name);
-  }
-
-  assertGlobalBinding(
-    name: string,
-    localScope?: BabelScope,
-  ): Result<void, CompilerError> {
-    const scope = localScope ?? this.scope;
-    if (!scope.hasReference(name) && !scope.hasBinding(name)) {
-      return Ok(undefined);
-    }
-    const error = new CompilerError();
-    error.push({
-      severity: ErrorSeverity.Todo,
-      reason: 'Encountered conflicting global in generated program',
-      description: `Conflict from local binding ${name}`,
-      loc: scope.getBinding(name)?.path.node.loc ?? null,
-      suggestions: null,
-    });
-    return Err(error);
-  }
-
-  logEvent(event: LoggerEvent): void {
-    if (this.opts.logger != null) {
-      this.opts.logger.logEvent(this.filename, event);
-    }
-  }
-}
-
-function getExistingImports(
-  program: NodePath<t.Program>,
-): Map<string, NodePath<t.ImportDeclaration>> {
-  const existingImports = new Map<string, NodePath<t.ImportDeclaration>>();
-  program.traverse({
-    ImportDeclaration(path) {
-      if (isNonNamespacedImport(path)) {
-        existingImports.set(path.node.source.value, path);
-      }
-    },
-  });
-  return existingImports;
-}
-
 export function addImportsToProgram(
   path: NodePath<t.Program>,
-  programContext: ProgramContext,
+  importList: Array<ExternalFunction>,
 ): void {
-  const existingImports = getExistingImports(path);
+  const identifiers: Set<string> = new Set();
+  const sortedImports: Map<string, Array<string>> = new Map();
+  for (const {importSpecifierName, source} of importList) {
+    /*
+     * Codegen currently does not rename import specifiers, so we do additional
+     * validation here
+     */
+    CompilerError.invariant(identifiers.has(importSpecifierName) === false, {
+      reason: `Encountered conflicting import specifier for ${importSpecifierName} in Forget config.`,
+      description: null,
+      loc: GeneratedSource,
+      suggestions: null,
+    });
+    CompilerError.invariant(
+      path.scope.hasBinding(importSpecifierName) === false,
+      {
+        reason: `Encountered conflicting import specifiers for ${importSpecifierName} in generated program.`,
+        description: null,
+        loc: GeneratedSource,
+        suggestions: null,
+      },
+    );
+    identifiers.add(importSpecifierName);
+
+    const importSpecifierNameList = getOrInsertDefault(
+      sortedImports,
+      source,
+      [],
+    );
+    importSpecifierNameList.push(importSpecifierName);
+  }
+
   const stmts: Array<t.ImportDeclaration> = [];
-  const sortedModules = [...programContext.imports.entries()].sort(([a], [b]) =>
-    a.localeCompare(b),
-  );
-  for (const [moduleName, importsMap] of sortedModules) {
-    for (const [specifierName, loweredImport] of importsMap) {
-      /**
-       * Assert that the import identifier hasn't already be declared in the program.
-       * Note: we use getBinding here since `Scope.hasBinding` pessimistically returns true
-       * for all allocated uids (from `Scope.getUid`)
-       */
-      CompilerError.invariant(
-        path.scope.getBinding(loweredImport.name) == null,
-        {
-          reason:
-            'Encountered conflicting import specifiers in generated program',
-          description: `Conflict from import ${loweredImport.module}:(${loweredImport.imported} as ${loweredImport.name}).`,
-          loc: GeneratedSource,
-          suggestions: null,
-        },
-      );
-      CompilerError.invariant(
-        loweredImport.module === moduleName &&
-          loweredImport.imported === specifierName,
-        {
-          reason:
-            'Found inconsistent import specifier. This is an internal bug.',
-          description: `Expected import ${moduleName}:${specifierName} but found ${loweredImport.module}:${loweredImport.imported}`,
-          loc: GeneratedSource,
-        },
-      );
-    }
-    const sortedImport: Array<NonLocalImportSpecifier> = [
-      ...importsMap.values(),
-    ].sort(({imported: a}, {imported: b}) => a.localeCompare(b));
-    const importSpecifiers = sortedImport.map(specifier => {
-      return t.importSpecifier(
-        t.identifier(specifier.name),
-        t.identifier(specifier.imported),
-      );
+  for (const [source, importSpecifierNameList] of sortedImports) {
+    const importSpecifiers = importSpecifierNameList.map(name => {
+      const id = t.identifier(name);
+      return t.importSpecifier(id, id);
     });
 
-    /**
-     * If an existing import of this module exists (ie `import { ... } from
-     * '<moduleName>'`), inject new imported specifiers into the list of
-     * destructured variables.
-     */
-    const maybeExistingImports = existingImports.get(moduleName);
-    if (maybeExistingImports != null) {
-      maybeExistingImports.pushContainer('specifiers', importSpecifiers);
-    } else {
-      stmts.push(
-        t.importDeclaration(importSpecifiers, t.stringLiteral(moduleName)),
-      );
-    }
+    stmts.push(t.importDeclaration(importSpecifiers, t.stringLiteral(source)));
   }
   path.unshiftContainer('body', stmts);
 }
@@ -302,12 +93,13 @@ export function addImportsToProgram(
 /*
  * Matches `import { ... } from <moduleName>;`
  * but not `import * as React from <moduleName>;`
- *         `import type { Foo } from <moduleName>;`
  */
 function isNonNamespacedImport(
   importDeclPath: NodePath<t.ImportDeclaration>,
+  moduleName: string,
 ): boolean {
   return (
+    importDeclPath.get('source').node.value === moduleName &&
     importDeclPath
       .get('specifiers')
       .every(specifier => specifier.isImportSpecifier()) &&
@@ -315,3 +107,94 @@ function isNonNamespacedImport(
     importDeclPath.node.importKind !== 'typeof'
   );
 }
+
+function hasExistingNonNamespacedImportOfModule(
+  program: NodePath<t.Program>,
+  moduleName: string,
+): boolean {
+  let hasExistingImport = false;
+  program.traverse({
+    ImportDeclaration(importDeclPath) {
+      if (isNonNamespacedImport(importDeclPath, moduleName)) {
+        hasExistingImport = true;
+      }
+    },
+  });
+
+  return hasExistingImport;
+}
+
+/*
+ * If an existing import of React exists (ie `import { ... } from '<moduleName>'`), inject useMemoCache
+ * into the list of destructured variables.
+ */
+function addMemoCacheFunctionSpecifierToExistingImport(
+  program: NodePath<t.Program>,
+  moduleName: string,
+  identifierName: string,
+): boolean {
+  let didInsertUseMemoCache = false;
+  program.traverse({
+    ImportDeclaration(importDeclPath) {
+      if (
+        !didInsertUseMemoCache &&
+        isNonNamespacedImport(importDeclPath, moduleName)
+      ) {
+        importDeclPath.pushContainer(
+          'specifiers',
+          t.importSpecifier(t.identifier(identifierName), t.identifier('c')),
+        );
+        didInsertUseMemoCache = true;
+      }
+    },
+  });
+  return didInsertUseMemoCache;
+}
+
+export function updateMemoCacheFunctionImport(
+  program: NodePath<t.Program>,
+  moduleName: string,
+  useMemoCacheIdentifier: string,
+): void {
+  /*
+   * If there isn't already an import of * as React, insert it so useMemoCache doesn't
+   * throw
+   */
+  const hasExistingImport = hasExistingNonNamespacedImportOfModule(
+    program,
+    moduleName,
+  );
+
+  if (hasExistingImport) {
+    const didUpdateImport = addMemoCacheFunctionSpecifierToExistingImport(
+      program,
+      moduleName,
+      useMemoCacheIdentifier,
+    );
+    if (!didUpdateImport) {
+      throw new Error(
+        `Expected an ImportDeclaration of \`${moduleName}\` in order to update ImportSpecifiers with useMemoCache`,
+      );
+    }
+  } else {
+    addMemoCacheFunctionImportDeclaration(
+      program,
+      moduleName,
+      useMemoCacheIdentifier,
+    );
+  }
+}
+
+function addMemoCacheFunctionImportDeclaration(
+  program: NodePath<t.Program>,
+  moduleName: string,
+  localName: string,
+): void {
+  program.unshiftContainer(
+    'body',
+    t.importDeclaration(
+      [t.importSpecifier(t.identifier(localName), t.identifier('c'))],
+      t.stringLiteral(moduleName),
+    ),
+  );
+}

compiler/packages/babel-plugin-react-compiler/src/Entrypoint/Options.ts

@@ -7,17 +7,11 @@
 
 import * as t from '@babel/types';
 import {z} from 'zod';
-import {
-  CompilerDiagnostic,
-  CompilerError,
-  CompilerErrorDetail,
-  CompilerErrorDetailOptions,
-} from '../CompilerError';
+import {CompilerError, CompilerErrorDetailOptions} from '../CompilerError';
 import {
   EnvironmentConfig,
   ExternalFunction,
   parseEnvironmentConfig,
-  tryParseExternalFunction,
 } from '../HIR/Environment';
 import {hasOwnProperty} from '../Utils/utils';
 import {fromZodError} from 'zod-validation-error';
@@ -42,14 +36,6 @@ const PanicThresholdOptionsSchema = z.enum([
 ]);
 
 export type PanicThresholdOptions = z.infer<typeof PanicThresholdOptionsSchema>;
-const DynamicGatingOptionsSchema = z.object({
-  source: z.string(),
-});
-export type DynamicGatingOptions = z.infer<typeof DynamicGatingOptionsSchema>;
-const CustomOptOutDirectiveSchema = z
-  .nullable(z.array(z.string()))
-  .default(null);
-type CustomOptOutDirective = z.infer<typeof CustomOptOutDirectiveSchema>;
 
 export type PluginOptions = {
   environment: EnvironmentConfig;
@@ -78,28 +64,6 @@ export type PluginOptions = {
    */
   gating: ExternalFunction | null;
 
-  /**
-   * If specified, this enables dynamic gating which matches `use memo if(...)`
-   * directives.
-   *
-   * Example usage:
-   * ```js
-   * // @dynamicGating:{"source":"myModule"}
-   * export function MyComponent() {
-   *   'use memo if(isEnabled)';
-   *    return <div>...</div>;
-   * }
-   * ```
-   * This will emit:
-   * ```js
-   * import {isEnabled} from 'myModule';
-   * export const MyComponent = isEnabled()
-   *   ? <optimized version>
-   *   : <original version>;
-   * ```
-   */
-  dynamicGating: DynamicGatingOptions | null;
-
   panicThreshold: PanicThresholdOptions;
 
   /*
@@ -133,7 +97,7 @@ export type PluginOptions = {
    * provided rules will skip compilation. To disable this feature (never bailout of compilation
    * even if the default ESLint is suppressed), pass an empty array.
    */
-  eslintSuppressionRules: Array<string> | null | undefined;
+  eslintSuppressionRules?: Array<string> | null | undefined;
 
   flowSuppressions: boolean;
   /*
@@ -141,12 +105,7 @@ export type PluginOptions = {
    */
   ignoreUseNoForget: boolean;
 
-  /**
-   * Unstable / do not use
-   */
-  customOptOutDirectives: CustomOptOutDirective;
-
-  sources: Array<string> | ((filename: string) => boolean) | null;
+  sources?: Array<string> | ((filename: string) => boolean) | null;
 
   /**
    * The compiler has customized support for react-native-reanimated, intended as a temporary workaround.
@@ -222,14 +181,12 @@ export type LoggerEvent =
   | CompileDiagnosticEvent
   | CompileSkipEvent
   | PipelineErrorEvent
-  | TimingEvent
-  | AutoDepsDecorationsEvent
-  | AutoDepsEligibleEvent;
+  | TimingEvent;
 
 export type CompileErrorEvent = {
   kind: 'CompileError';
   fnLoc: t.SourceLocation | null;
-  detail: CompilerErrorDetail | CompilerDiagnostic;
+  detail: CompilerErrorDetailOptions;
 };
 export type CompileDiagnosticEvent = {
   kind: 'CompileDiagnostic';
@@ -261,16 +218,6 @@ export type TimingEvent = {
   kind: 'Timing';
   measurement: PerformanceMeasure;
 };
-export type AutoDepsDecorationsEvent = {
-  kind: 'AutoDepsDecorations';
-  fnLoc: t.SourceLocation;
-  decorations: Array<t.SourceLocation>;
-};
-export type AutoDepsEligibleEvent = {
-  kind: 'AutoDepsEligible';
-  fnLoc: t.SourceLocation;
-  depArrayLoc: t.SourceLocation;
-};
 
 export type Logger = {
   logEvent: (filename: string | null, event: LoggerEvent) => void;
@@ -284,7 +231,6 @@ export const defaultOptions: PluginOptions = {
   logger: null,
   gating: null,
   noEmit: false,
-  dynamicGating: null,
   eslintSuppressionRules: null,
   flowSuppressions: true,
   ignoreUseNoForget: false,
@@ -292,7 +238,6 @@ export const defaultOptions: PluginOptions = {
     return filename.indexOf('node_modules') === -1;
   },
   enableReanimatedCheck: true,
-  customOptOutDirectives: null,
   target: '19',
 } as const;
 
@@ -326,48 +271,6 @@ export function parsePluginOptions(obj: unknown): PluginOptions {
           parsedOptions[key] = parseTargetConfig(value);
           break;
         }
-        case 'gating': {
-          if (value == null) {
-            parsedOptions[key] = null;
-          } else {
-            parsedOptions[key] = tryParseExternalFunction(value);
-          }
-          break;
-        }
-        case 'dynamicGating': {
-          if (value == null) {
-            parsedOptions[key] = null;
-          } else {
-            const result = DynamicGatingOptionsSchema.safeParse(value);
-            if (result.success) {
-              parsedOptions[key] = result.data;
-            } else {
-              CompilerError.throwInvalidConfig({
-                reason:
-                  'Could not parse dynamic gating. Update React Compiler config to fix the error',
-                description: `${fromZodError(result.error)}`,
-                loc: null,
-                suggestions: null,
-              });
-            }
-          }
-          break;
-        }
-        case 'customOptOutDirectives': {
-          const result = CustomOptOutDirectiveSchema.safeParse(value);
-          if (result.success) {
-            parsedOptions[key] = result.data;
-          } else {
-            CompilerError.throwInvalidConfig({
-              reason:
-                'Could not parse custom opt out directives. Update React Compiler config to fix the error',
-              description: `${fromZodError(result.error)}`,
-              loc: null,
-              suggestions: null,
-            });
-          }
-          break;
-        }
         default: {
           parsedOptions[key] = value;
         }

compiler/packages/babel-plugin-react-compiler/src/Entrypoint/Pipeline.ts

@@ -8,7 +8,7 @@
 import {NodePath} from '@babel/traverse';
 import * as t from '@babel/types';
 import prettyFormat from 'pretty-format';
-import {Logger, ProgramContext} from '.';
+import {Logger} from '.';
 import {
   HIRFunction,
   ReactiveFunction,
@@ -24,7 +24,6 @@ import {
   pruneUnusedLabelsHIR,
 } from '../HIR';
 import {
-  CompilerMode,
   Environment,
   EnvironmentConfig,
   ReactFunctionType,
@@ -94,18 +93,13 @@ import {validateLocalsNotReassignedAfterRender} from '../Validation/ValidateLoca
 import {outlineFunctions} from '../Optimization/OutlineFunctions';
 import {propagatePhiTypes} from '../TypeInference/PropagatePhiTypes';
 import {lowerContextAccess} from '../Optimization/LowerContextAccess';
-import {validateNoSetStateInEffects} from '../Validation/ValidateNoSetStateInEffects';
+import {validateNoSetStateInPassiveEffects} from '../Validation/ValidateNoSetStateInPassiveEffects';
 import {validateNoJSXInTryStatement} from '../Validation/ValidateNoJSXInTryStatement';
 import {propagateScopeDependenciesHIR} from '../HIR/PropagateScopeDependenciesHIR';
 import {outlineJSX} from '../Optimization/OutlineJsx';
 import {optimizePropsMethodCalls} from '../Optimization/OptimizePropsMethodCalls';
 import {transformFire} from '../Transform';
-import {validateNoImpureFunctionsInRender} from '../Validation/ValidateNoImpureFunctionsInRender';
-import {CompilerError} from '..';
-import {validateStaticComponents} from '../Validation/ValidateStaticComponents';
-import {validateNoFreezingKnownMutableFunctions} from '../Validation/ValidateNoFreezingKnownMutableFunctions';
-import {inferMutationAliasingEffects} from '../Inference/InferMutationAliasingEffects';
-import {inferMutationAliasingRanges} from '../Inference/InferMutationAliasingRanges';
+import {validateNoImpureFunctionsInRender} from '../Validation/ValiateNoImpureFunctionsInRender';
 
 export type CompilerPipelineValue =
   | {kind: 'ast'; name: string; value: CodegenFunction}
@@ -119,8 +113,7 @@ function run(
   >,
   config: EnvironmentConfig,
   fnType: ReactFunctionType,
-  mode: CompilerMode,
-  programContext: ProgramContext,
+  useMemoCacheIdentifier: string,
   logger: Logger | null,
   filename: string | null,
   code: string | null,
@@ -129,14 +122,12 @@ function run(
   const env = new Environment(
     func.scope,
     fnType,
-    mode,
     config,
     contextIdentifiers,
-    func,
     logger,
     filename,
     code,
-    programContext,
+    useMemoCacheIdentifier,
   );
   env.logger?.debugLogIRs?.({
     kind: 'debug',
@@ -166,15 +157,15 @@ function runWithEnvironment(
   log({kind: 'hir', name: 'PruneMaybeThrows', value: hir});
 
   validateContextVariableLValues(hir);
-  validateUseMemo(hir).unwrap();
+  validateUseMemo(hir);
 
   if (
-    env.isInferredMemoEnabled &&
     !env.config.enablePreserveExistingManualUseMemo &&
     !env.config.disableMemoizationForDebugging &&
-    !env.config.enableChangeDetectionForDebugging
+    !env.config.enableChangeDetectionForDebugging &&
+    !env.config.enableMinimalTransformsForRetry
   ) {
-    dropManualMemoization(hir).unwrap();
+    dropManualMemoization(hir);
     log({kind: 'hir', name: 'DropManualMemoization', value: hir});
   }
 
@@ -205,13 +196,8 @@ function runWithEnvironment(
   inferTypes(hir);
   log({kind: 'hir', name: 'InferTypes', value: hir});
 
-  if (env.isInferredMemoEnabled) {
-    if (env.config.validateHooksUsage) {
-      validateHooksUsage(hir).unwrap();
-    }
-    if (env.config.validateNoCapitalizedCalls) {
-      validateNoCapitalizedCalls(hir).unwrap();
-    }
+  if (env.config.validateHooksUsage) {
+    validateHooksUsage(hir);
   }
 
   if (env.config.enableFire) {
@@ -219,6 +205,10 @@ function runWithEnvironment(
     log({kind: 'hir', name: 'TransformFire', value: hir});
   }
 
+  if (env.config.validateNoCapitalizedCalls) {
+    validateNoCapitalizedCalls(hir);
+  }
+
   if (env.config.lowerContextAccess) {
     lowerContextAccess(hir, env.config.lowerContextAccess);
   }
@@ -229,27 +219,10 @@ function runWithEnvironment(
   analyseFunctions(hir);
   log({kind: 'hir', name: 'AnalyseFunctions', value: hir});
 
-  if (!env.config.enableNewMutationAliasingModel) {
-    const fnEffectErrors = inferReferenceEffects(hir);
-    if (env.isInferredMemoEnabled) {
-      if (fnEffectErrors.length > 0) {
-        CompilerError.throw(fnEffectErrors[0]);
-      }
-    }
-    log({kind: 'hir', name: 'InferReferenceEffects', value: hir});
-  } else {
-    const mutabilityAliasingErrors = inferMutationAliasingEffects(hir);
-    log({kind: 'hir', name: 'InferMutationAliasingEffects', value: hir});
-    if (env.isInferredMemoEnabled) {
-      if (mutabilityAliasingErrors.isErr()) {
-        throw mutabilityAliasingErrors.unwrapErr();
-      }
-    }
-  }
+  inferReferenceEffects(hir);
+  log({kind: 'hir', name: 'InferReferenceEffects', value: hir});
 
-  if (!env.config.enableNewMutationAliasingModel) {
-    validateLocalsNotReassignedAfterRender(hir);
-  }
+  validateLocalsNotReassignedAfterRender(hir);
 
   // Note: Has to come after infer reference effects because "dead" code may still affect inference
   deadCodeElimination(hir);
@@ -263,53 +236,31 @@ function runWithEnvironment(
   pruneMaybeThrows(hir);
   log({kind: 'hir', name: 'PruneMaybeThrows', value: hir});
 
-  if (!env.config.enableNewMutationAliasingModel) {
-    inferMutableRanges(hir);
-    log({kind: 'hir', name: 'InferMutableRanges', value: hir});
-  } else {
-    const mutabilityAliasingErrors = inferMutationAliasingRanges(hir, {
-      isFunctionExpression: false,
-    });
-    log({kind: 'hir', name: 'InferMutationAliasingRanges', value: hir});
-    if (env.isInferredMemoEnabled) {
-      if (mutabilityAliasingErrors.isErr()) {
-        throw mutabilityAliasingErrors.unwrapErr();
-      }
-      validateLocalsNotReassignedAfterRender(hir);
-    }
+  inferMutableRanges(hir);
+  log({kind: 'hir', name: 'InferMutableRanges', value: hir});
+
+  if (env.config.assertValidMutableRanges) {
+    assertValidMutableRanges(hir);
   }
 
-  if (env.isInferredMemoEnabled) {
-    if (env.config.assertValidMutableRanges) {
-      assertValidMutableRanges(hir);
-    }
+  if (env.config.validateRefAccessDuringRender) {
+    validateNoRefAccessInRender(hir);
+  }
 
-    if (env.config.validateRefAccessDuringRender) {
-      validateNoRefAccessInRender(hir).unwrap();
-    }
+  if (env.config.validateNoSetStateInRender) {
+    validateNoSetStateInRender(hir);
+  }
 
-    if (env.config.validateNoSetStateInRender) {
-      validateNoSetStateInRender(hir).unwrap();
-    }
+  if (env.config.validateNoSetStateInPassiveEffects) {
+    validateNoSetStateInPassiveEffects(hir);
+  }
 
-    if (env.config.validateNoSetStateInEffects) {
-      env.logErrors(validateNoSetStateInEffects(hir));
-    }
+  if (env.config.validateNoJSXInTryStatements) {
+    validateNoJSXInTryStatement(hir);
+  }
 
-    if (env.config.validateNoJSXInTryStatements) {
-      env.logErrors(validateNoJSXInTryStatement(hir));
-    }
-
-    if (env.config.validateNoImpureFunctionsInRender) {
-      validateNoImpureFunctionsInRender(hir).unwrap();
-    }
-
-    if (
-      env.config.validateNoFreezingKnownMutableFunctions ||
-      env.config.enableNewMutationAliasingModel
-    ) {
-      validateNoFreezingKnownMutableFunctions(hir).unwrap();
-    }
+  if (env.config.validateNoImpureFunctionsInRender) {
+    validateNoImpureFunctionsInRender(hir);
   }
 
   inferReactivePlaces(hir);
@@ -329,16 +280,7 @@ function runWithEnvironment(
     value: hir,
   });
 
-  if (env.isInferredMemoEnabled) {
-    if (env.config.validateStaticComponents) {
-      env.logErrors(validateStaticComponents(hir));
-    }
-
-    /**
-     * Only create reactive scopes (which directly map to generated memo blocks)
-     * if inferred memoization is enabled. This makes all later passes which
-     * transform reactive-scope labeled instructions no-ops.
-     */
+  if (!env.config.enableMinimalTransformsForRetry) {
     inferReactiveScopeVariables(hir);
     log({kind: 'hir', name: 'InferReactiveScopeVariables', value: hir});
   }
@@ -428,11 +370,6 @@ function runWithEnvironment(
 
   if (env.config.inferEffectDependencies) {
     inferEffectDependencies(hir);
-    log({
-      kind: 'hir',
-      name: 'InferEffectDependencies',
-      value: hir,
-    });
   }
 
   if (env.config.inlineJsxTransform) {
@@ -555,14 +492,14 @@ function runWithEnvironment(
   });
 
   if (env.config.validateMemoizedEffectDependencies) {
-    validateMemoizedEffectDependencies(reactiveFunction).unwrap();
+    validateMemoizedEffectDependencies(reactiveFunction);
   }
 
   if (
     env.config.enablePreserveExistingMemoizationGuarantees ||
     env.config.validatePreserveExistingMemoizationGuarantees
   ) {
-    validatePreservedManualMemoization(reactiveFunction).unwrap();
+    validatePreservedManualMemoization(reactiveFunction);
   }
 
   const ast = codegenFunction(reactiveFunction, {
@@ -592,8 +529,7 @@ export function compileFn(
   >,
   config: EnvironmentConfig,
   fnType: ReactFunctionType,
-  mode: CompilerMode,
-  programContext: ProgramContext,
+  useMemoCacheIdentifier: string,
   logger: Logger | null,
   filename: string | null,
   code: string | null,
@@ -602,8 +538,7 @@ export function compileFn(
     func,
     config,
     fnType,
-    mode,
-    programContext,
+    useMemoCacheIdentifier,
     logger,
     filename,
     code,

compiler/packages/babel-plugin-react-compiler/src/Entrypoint/Reanimated.ts

@@ -1,10 +1,3 @@
-/**
- * Copyright (c) Meta Platforms, Inc. and affiliates.
- *
- * This source code is licensed under the MIT license found in the
- * LICENSE file in the root directory of this source tree.
- */
-
 import type * as BabelCore from '@babel/core';
 import {hasOwnProperty} from '../Utils/utils';
 import {PluginOptions} from './Options';

compiler/packages/babel-plugin-react-compiler/src/Entrypoint/Suppression.ts

@@ -8,8 +8,8 @@
 import {NodePath} from '@babel/core';
 import * as t from '@babel/types';
 import {
-  CompilerDiagnostic,
   CompilerError,
+  CompilerErrorDetail,
   CompilerSuggestionOperation,
   ErrorSeverity,
 } from '../CompilerError';
@@ -181,11 +181,12 @@ export function suppressionsToCompilerError(
           'Unhandled suppression source',
         );
     }
-    error.pushDiagnostic(
-      CompilerDiagnostic.create({
-        category: reason,
-        description: `React Compiler only works when your components follow all the rules of React, disabling them may result in unexpected or incorrect behavior. Found suppression \`${suppressionRange.disableComment.value.trim()}\``,
+    error.pushErrorDetail(
+      new CompilerErrorDetail({
+        reason: `${reason}. React Compiler only works when your components follow all the rules of React, disabling them may result in unexpected or incorrect behavior`,
+        description: suppressionRange.disableComment.value.trim(),
         severity: ErrorSeverity.InvalidReact,
+        loc: suppressionRange.disableComment.loc ?? null,
         suggestions: [
           {
             description: suggestion,
@@ -196,10 +197,6 @@ export function suppressionsToCompilerError(
             op: CompilerSuggestionOperation.Remove,
           },
         ],
-      }).withDetail({
-        kind: 'error',
-        loc: suppressionRange.disableComment.loc ?? null,
-        message: 'Found React rule suppression',
       }),
     );
   }

compiler/packages/babel-plugin-react-compiler/src/Entrypoint/ValidateNoUntransformedReferences.ts

@@ -1,328 +0,0 @@
-/**
- * Copyright (c) Meta Platforms, Inc. and affiliates.
- *
- * This source code is licensed under the MIT license found in the
- * LICENSE file in the root directory of this source tree.
- */
-
-import {NodePath} from '@babel/core';
-import * as t from '@babel/types';
-
-import {CompilerError, EnvironmentConfig, ErrorSeverity, Logger} from '..';
-import {getOrInsertWith} from '../Utils/utils';
-import {Environment, GeneratedSource} from '../HIR';
-import {DEFAULT_EXPORT} from '../HIR/Environment';
-import {CompileProgramMetadata} from './Program';
-import {CompilerDiagnostic, CompilerDiagnosticOptions} from '../CompilerError';
-
-function throwInvalidReact(
-  options: Omit<CompilerDiagnosticOptions, 'severity'>,
-  {logger, filename}: TraversalState,
-): never {
-  const detail: CompilerDiagnosticOptions = {
-    severity: ErrorSeverity.InvalidReact,
-    ...options,
-  };
-  logger?.logEvent(filename, {
-    kind: 'CompileError',
-    fnLoc: null,
-    detail: new CompilerDiagnostic(detail),
-  });
-  CompilerError.throwDiagnostic(detail);
-}
-
-function isAutodepsSigil(
-  arg: NodePath<t.ArgumentPlaceholder | t.SpreadElement | t.Expression>,
-): boolean {
-  // Check for AUTODEPS identifier imported from React
-  if (arg.isIdentifier() && arg.node.name === 'AUTODEPS') {
-    const binding = arg.scope.getBinding(arg.node.name);
-    if (binding && binding.path.isImportSpecifier()) {
-      const importSpecifier = binding.path.node as t.ImportSpecifier;
-      if (importSpecifier.imported.type === 'Identifier') {
-        return (importSpecifier.imported as t.Identifier).name === 'AUTODEPS';
-      }
-    }
-    return false;
-  }
-
-  // Check for React.AUTODEPS member expression
-  if (arg.isMemberExpression() && !arg.node.computed) {
-    const object = arg.get('object');
-    const property = arg.get('property');
-
-    if (
-      object.isIdentifier() &&
-      object.node.name === 'React' &&
-      property.isIdentifier() &&
-      property.node.name === 'AUTODEPS'
-    ) {
-      return true;
-    }
-  }
-
-  return false;
-}
-function assertValidEffectImportReference(
-  autodepsIndex: number,
-  paths: Array<NodePath<t.Node>>,
-  context: TraversalState,
-): void {
-  for (const path of paths) {
-    const parent = path.parentPath;
-    if (parent != null && parent.isCallExpression()) {
-      const args = parent.get('arguments');
-      const maybeCalleeLoc = path.node.loc;
-      const hasInferredEffect =
-        maybeCalleeLoc != null &&
-        context.inferredEffectLocations.has(maybeCalleeLoc);
-      /**
-       * Error on effect calls that still have AUTODEPS in their args
-       */
-      const hasAutodepsArg = args.some(isAutodepsSigil);
-      if (hasAutodepsArg && !hasInferredEffect) {
-        const maybeErrorDiagnostic = matchCompilerDiagnostic(
-          path,
-          context.transformErrors,
-        );
-        /**
-         * Note that we cannot easily check the type of the first argument here,
-         * as it may have already been transformed by the compiler (and not
-         * memoized).
-         */
-        throwInvalidReact(
-          {
-            category:
-              'Cannot infer dependencies of this effect. This will break your build!',
-            description:
-              'To resolve, either pass a dependency array or fix reported compiler bailout diagnostics.' +
-              (maybeErrorDiagnostic ? ` ${maybeErrorDiagnostic}` : ''),
-            details: [
-              {
-                kind: 'error',
-                message: 'Cannot infer dependencies',
-                loc: parent.node.loc ?? GeneratedSource,
-              },
-            ],
-          },
-          context,
-        );
-      }
-    }
-  }
-}
-
-function assertValidFireImportReference(
-  paths: Array<NodePath<t.Node>>,
-  context: TraversalState,
-): void {
-  if (paths.length > 0) {
-    const maybeErrorDiagnostic = matchCompilerDiagnostic(
-      paths[0],
-      context.transformErrors,
-    );
-    throwInvalidReact(
-      {
-        category:
-          '[Fire] Untransformed reference to compiler-required feature.',
-        description:
-          'Either remove this `fire` call or ensure it is successfully transformed by the compiler' +
-          maybeErrorDiagnostic
-            ? ` ${maybeErrorDiagnostic}`
-            : '',
-        details: [
-          {
-            kind: 'error',
-            message: 'Untransformed `fire` call',
-            loc: paths[0].node.loc ?? GeneratedSource,
-          },
-        ],
-      },
-      context,
-    );
-  }
-}
-export default function validateNoUntransformedReferences(
-  path: NodePath<t.Program>,
-  filename: string | null,
-  logger: Logger | null,
-  env: EnvironmentConfig,
-  compileResult: CompileProgramMetadata | null,
-): void {
-  const moduleLoadChecks = new Map<
-    string,
-    Map<string, CheckInvalidReferenceFn>
-  >();
-  if (env.enableFire) {
-    /**
-     * Error on any untransformed references to `fire` (e.g. including non-call
-     * expressions)
-     */
-    for (const module of Environment.knownReactModules) {
-      const react = getOrInsertWith(moduleLoadChecks, module, () => new Map());
-      react.set('fire', assertValidFireImportReference);
-    }
-  }
-  if (env.inferEffectDependencies) {
-    for (const {
-      function: {source, importSpecifierName},
-      autodepsIndex,
-    } of env.inferEffectDependencies) {
-      const module = getOrInsertWith(moduleLoadChecks, source, () => new Map());
-      module.set(
-        importSpecifierName,
-        assertValidEffectImportReference.bind(null, autodepsIndex),
-      );
-    }
-  }
-  if (moduleLoadChecks.size > 0) {
-    transformProgram(path, moduleLoadChecks, filename, logger, compileResult);
-  }
-}
-
-type TraversalState = {
-  shouldInvalidateScopes: boolean;
-  program: NodePath<t.Program>;
-  logger: Logger | null;
-  filename: string | null;
-  transformErrors: Array<{fn: NodePath<t.Node>; error: CompilerError}>;
-  inferredEffectLocations: Set<t.SourceLocation>;
-};
-type CheckInvalidReferenceFn = (
-  paths: Array<NodePath<t.Node>>,
-  context: TraversalState,
-) => void;
-
-function validateImportSpecifier(
-  specifier: NodePath<t.ImportSpecifier>,
-  importSpecifierChecks: Map<string, CheckInvalidReferenceFn>,
-  state: TraversalState,
-): void {
-  const imported = specifier.get('imported');
-  const specifierName: string =
-    imported.node.type === 'Identifier'
-      ? imported.node.name
-      : imported.node.value;
-  const checkFn = importSpecifierChecks.get(specifierName);
-  if (checkFn == null) {
-    return;
-  }
-  if (state.shouldInvalidateScopes) {
-    state.shouldInvalidateScopes = false;
-    state.program.scope.crawl();
-  }
-
-  const local = specifier.get('local');
-  const binding = local.scope.getBinding(local.node.name);
-  CompilerError.invariant(binding != null, {
-    reason: 'Expected binding to be found for import specifier',
-    loc: local.node.loc ?? null,
-  });
-  checkFn(binding.referencePaths, state);
-}
-
-function validateNamespacedImport(
-  specifier: NodePath<t.ImportNamespaceSpecifier | t.ImportDefaultSpecifier>,
-  importSpecifierChecks: Map<string, CheckInvalidReferenceFn>,
-  state: TraversalState,
-): void {
-  if (state.shouldInvalidateScopes) {
-    state.shouldInvalidateScopes = false;
-    state.program.scope.crawl();
-  }
-  const local = specifier.get('local');
-  const binding = local.scope.getBinding(local.node.name);
-  const defaultCheckFn = importSpecifierChecks.get(DEFAULT_EXPORT);
-
-  CompilerError.invariant(binding != null, {
-    reason: 'Expected binding to be found for import specifier',
-    loc: local.node.loc ?? null,
-  });
-  const filteredReferences = new Map<
-    CheckInvalidReferenceFn,
-    Array<NodePath<t.Node>>
-  >();
-  for (const reference of binding.referencePaths) {
-    if (defaultCheckFn != null) {
-      getOrInsertWith(filteredReferences, defaultCheckFn, () => []).push(
-        reference,
-      );
-    }
-    const parent = reference.parentPath;
-    if (
-      parent != null &&
-      parent.isMemberExpression() &&
-      parent.get('object') === reference
-    ) {
-      if (parent.node.computed || parent.node.property.type !== 'Identifier') {
-        continue;
-      }
-      const checkFn = importSpecifierChecks.get(parent.node.property.name);
-      if (checkFn != null) {
-        getOrInsertWith(filteredReferences, checkFn, () => []).push(parent);
-      }
-    }
-  }
-
-  for (const [checkFn, references] of filteredReferences) {
-    checkFn(references, state);
-  }
-}
-function transformProgram(
-  path: NodePath<t.Program>,
-
-  moduleLoadChecks: Map<string, Map<string, CheckInvalidReferenceFn>>,
-  filename: string | null,
-  logger: Logger | null,
-  compileResult: CompileProgramMetadata | null,
-): void {
-  const traversalState: TraversalState = {
-    shouldInvalidateScopes: true,
-    program: path,
-    filename,
-    logger,
-    transformErrors: compileResult?.retryErrors ?? [],
-    inferredEffectLocations:
-      compileResult?.inferredEffectLocations ?? new Set(),
-  };
-  path.traverse({
-    ImportDeclaration(path: NodePath<t.ImportDeclaration>) {
-      const importSpecifierChecks = moduleLoadChecks.get(
-        path.node.source.value,
-      );
-      if (importSpecifierChecks == null) {
-        return;
-      }
-      const specifiers = path.get('specifiers');
-      for (const specifier of specifiers) {
-        if (specifier.isImportSpecifier()) {
-          validateImportSpecifier(
-            specifier,
-            importSpecifierChecks,
-            traversalState,
-          );
-        } else {
-          validateNamespacedImport(
-            specifier as NodePath<
-              t.ImportNamespaceSpecifier | t.ImportDefaultSpecifier
-            >,
-            importSpecifierChecks,
-            traversalState,
-          );
-        }
-      }
-    },
-  });
-}
-
-function matchCompilerDiagnostic(
-  badReference: NodePath<t.Node>,
-  transformErrors: Array<{fn: NodePath<t.Node>; error: CompilerError}>,
-): string | null {
-  for (const {fn, error} of transformErrors) {
-    if (fn.isAncestor(badReference)) {
-      return error.toString();
-    }
-  }
-  return null;
-}

compiler/packages/babel-plugin-react-compiler/src/HIR/AssertValidBlockNesting.ts

@@ -1,10 +1,3 @@
-/**
- * Copyright (c) Meta Platforms, Inc. and affiliates.
- *
- * This source code is licensed under the MIT license found in the
- * LICENSE file in the root directory of this source tree.
- */
-
 import {CompilerError} from '..';
 import {
   BlockId,

compiler/packages/babel-plugin-react-compiler/src/HIR/AssertValidMutableRanges.ts

@@ -5,14 +5,13 @@
  * LICENSE file in the root directory of this source tree.
  */
 
-import {HIRFunction, MutableRange, Place} from './HIR';
+import invariant from 'invariant';
+import {HIRFunction, Identifier, MutableRange} from './HIR';
 import {
   eachInstructionLValue,
   eachInstructionOperand,
   eachTerminalOperand,
 } from './visitors';
-import {CompilerError} from '..';
-import {printPlace} from './PrintHIR';
 
 /*
  * Checks that all mutable ranges in the function are well-formed, with
@@ -21,43 +20,38 @@ import {printPlace} from './PrintHIR';
 export function assertValidMutableRanges(fn: HIRFunction): void {
   for (const [, block] of fn.body.blocks) {
     for (const phi of block.phis) {
-      visit(phi.place, `phi for block bb${block.id}`);
-      for (const [pred, operand] of phi.operands) {
-        visit(operand, `phi predecessor bb${pred} for block bb${block.id}`);
+      visitIdentifier(phi.place.identifier);
+      for (const [, operand] of phi.operands) {
+        visitIdentifier(operand.identifier);
       }
     }
     for (const instr of block.instructions) {
       for (const operand of eachInstructionLValue(instr)) {
-        visit(operand, `instruction [${instr.id}]`);
+        visitIdentifier(operand.identifier);
       }
       for (const operand of eachInstructionOperand(instr)) {
-        visit(operand, `instruction [${instr.id}]`);
+        visitIdentifier(operand.identifier);
       }
     }
     for (const operand of eachTerminalOperand(block.terminal)) {
-      visit(operand, `terminal [${block.terminal.id}]`);
+      visitIdentifier(operand.identifier);
     }
   }
 }
 
-function visit(place: Place, description: string): void {
-  validateMutableRange(place, place.identifier.mutableRange, description);
-  if (place.identifier.scope !== null) {
-    validateMutableRange(place, place.identifier.scope.range, description);
+function visitIdentifier(identifier: Identifier): void {
+  validateMutableRange(identifier.mutableRange);
+  if (identifier.scope !== null) {
+    validateMutableRange(identifier.scope.range);
   }
 }
 
-function validateMutableRange(
-  place: Place,
-  range: MutableRange,
-  description: string,
-): void {
-  CompilerError.invariant(
-    (range.start === 0 && range.end === 0) || range.end > range.start,
-    {
-      reason: `Invalid mutable range: [${range.start}:${range.end}]`,
-      description: `${printPlace(place)} in ${description}`,
-      loc: place.loc,
-    },
+function validateMutableRange(mutableRange: MutableRange): void {
+  invariant(
+    (mutableRange.start === 0 && mutableRange.end === 0) ||
+      mutableRange.end > mutableRange.start,
+    'Identifier scope mutableRange was invalid: [%s:%s]',
+    mutableRange.start,
+    mutableRange.end,
   );
 }

compiler/packages/babel-plugin-react-compiler/src/HIR/BuildHIR.ts

@@ -9,7 +9,6 @@ import {NodePath, Scope} from '@babel/traverse';
 import * as t from '@babel/types';
 import invariant from 'invariant';
 import {
-  CompilerDiagnostic,
   CompilerError,
   CompilerSuggestionOperation,
   ErrorSeverity,
@@ -48,7 +47,7 @@ import {
   makeType,
   promoteTemporary,
 } from './HIR';
-import HIRBuilder, {Bindings, createTemporaryPlace} from './HIRBuilder';
+import HIRBuilder, {Bindings} from './HIRBuilder';
 import {BuiltInArrayId} from './ObjectShape';
 
 /*
@@ -71,23 +70,21 @@ import {BuiltInArrayId} from './ObjectShape';
 export function lower(
   func: NodePath<t.Function>,
   env: Environment,
-  // Bindings captured from the outer function, in case lower() is called recursively (for lambdas)
   bindings: Bindings | null = null,
-  capturedRefs: Map<t.Identifier, SourceLocation> = new Map(),
+  capturedRefs: Array<t.Identifier> = [],
+  // the outermost function being compiled, in case lower() is called recursively (for lambdas)
+  parent: NodePath<t.Function> | null = null,
 ): Result<HIRFunction, CompilerError> {
-  const builder = new HIRBuilder(env, {
-    bindings,
-    context: capturedRefs,
-  });
+  const builder = new HIRBuilder(env, parent ?? func, bindings, capturedRefs);
   const context: HIRFunction['context'] = [];
 
-  for (const [ref, loc] of capturedRefs ?? []) {
+  for (const ref of capturedRefs ?? []) {
     context.push({
       kind: 'Identifier',
       identifier: builder.resolveBinding(ref),
       effect: Effect.Unknown,
       reactive: false,
-      loc,
+      loc: ref.loc ?? GeneratedSource,
     });
   }
 
@@ -105,17 +102,12 @@ export function lower(
     if (param.isIdentifier()) {
       const binding = builder.resolveIdentifier(param);
       if (binding.kind !== 'Identifier') {
-        builder.errors.pushDiagnostic(
-          CompilerDiagnostic.create({
-            severity: ErrorSeverity.Invariant,
-            category: 'Could not find binding',
-            description: `[BuildHIR] Could not find binding for param \`${param.node.name}\`.`,
-          }).withDetail({
-            kind: 'error',
-            loc: param.node.loc ?? null,
-            message: 'Could not find binding',
-          }),
-        );
+        builder.errors.push({
+          reason: `(BuildHIR::lower) Could not find binding for param \`${param.node.name}\``,
+          severity: ErrorSeverity.Invariant,
+          loc: param.node.loc ?? null,
+          suggestions: null,
+        });
         return;
       }
       const place: Place = {
@@ -169,17 +161,12 @@ export function lower(
         'Assignment',
       );
     } else {
-      builder.errors.pushDiagnostic(
-        CompilerDiagnostic.create({
-          severity: ErrorSeverity.Todo,
-          category: `Handle ${param.node.type} parameters`,
-          description: `[BuildHIR] Add support for ${param.node.type} parameters.`,
-        }).withDetail({
-          kind: 'error',
-          loc: param.node.loc ?? null,
-          message: 'Unsupported parameter type',
-        }),
-      );
+      builder.errors.push({
+        reason: `(BuildHIR::lower) Handle ${param.node.type} params`,
+        severity: ErrorSeverity.Todo,
+        loc: param.node.loc ?? null,
+        suggestions: null,
+      });
     }
   });
 
@@ -189,28 +176,22 @@ export function lower(
     const fallthrough = builder.reserve('block');
     const terminal: ReturnTerminal = {
       kind: 'return',
-      returnVariant: 'Implicit',
       loc: GeneratedSource,
       value: lowerExpressionToTemporary(builder, body),
       id: makeInstructionId(0),
-      effects: null,
     };
     builder.terminateWithContinuation(terminal, fallthrough);
   } else if (body.isBlockStatement()) {
     lowerStatement(builder, body);
     directives = body.get('directives').map(d => d.node.value.value);
   } else {
-    builder.errors.pushDiagnostic(
-      CompilerDiagnostic.create({
-        severity: ErrorSeverity.InvalidJS,
-        category: `Unexpected function body kind`,
-        description: `Expected function body to be an expression or a block statement, got \`${body.type}\`.`,
-      }).withDetail({
-        kind: 'error',
-        loc: body.node.loc ?? null,
-        message: 'Expected a block statement or expression',
-      }),
-    );
+    builder.errors.push({
+      severity: ErrorSeverity.InvalidJS,
+      reason: `Unexpected function body kind`,
+      description: `Expected function body to be an expression or a block statement, got \`${body.type}\``,
+      loc: body.node.loc ?? null,
+      suggestions: null,
+    });
   }
 
   if (builder.errors.hasErrors()) {
@@ -220,7 +201,6 @@ export function lower(
   builder.terminate(
     {
       kind: 'return',
-      returnVariant: 'Void',
       loc: GeneratedSource,
       value: lowerValueToTemporary(builder, {
         kind: 'Primitive',
@@ -228,7 +208,6 @@ export function lower(
         loc: GeneratedSource,
       }),
       id: makeInstructionId(0),
-      effects: null,
     },
     null,
   );
@@ -236,9 +215,9 @@ export function lower(
   return Ok({
     id,
     params,
-    fnType: bindings == null ? env.fnType : 'Other',
+    fnType: parent == null ? env.fnType : 'Other',
     returnTypeAnnotation: null, // TODO: extract the actual return type node if present
-    returns: createTemporaryPlace(env, func.node.loc ?? GeneratedSource),
+    returnType: makeType(),
     body: builder.build(),
     context,
     generator: func.node.generator === true,
@@ -246,7 +225,6 @@ export function lower(
     loc: func.node.loc ?? GeneratedSource,
     env,
     effects: null,
-    aliasingEffects: null,
     directives,
   });
 }
@@ -304,11 +282,9 @@ function lowerStatement(
       }
       const terminal: ReturnTerminal = {
         kind: 'return',
-        returnVariant: 'Explicit',
         loc: stmt.node.loc ?? GeneratedSource,
         value,
         id: makeInstructionId(0),
-        effects: null,
       };
       builder.terminate(terminal, 'block');
       return;
@@ -1259,7 +1235,6 @@ function lowerStatement(
           kind: 'Debugger',
           loc,
         },
-        effects: null,
         loc,
       });
       return;
@@ -1373,85 +1348,13 @@ function lowerStatement(
 
       return;
     }
-    case 'WithStatement': {
-      builder.errors.push({
-        reason: `JavaScript 'with' syntax is not supported`,
-        description: `'with' syntax is considered deprecated and removed from JavaScript standards, consider alternatives`,
-        severity: ErrorSeverity.UnsupportedJS,
-        loc: stmtPath.node.loc ?? null,
-        suggestions: null,
-      });
-      lowerValueToTemporary(builder, {
-        kind: 'UnsupportedNode',
-        loc: stmtPath.node.loc ?? GeneratedSource,
-        node: stmtPath.node,
-      });
-      return;
-    }
-    case 'ClassDeclaration': {
-      /**
-       * In theory we could support inline class declarations, but this is rare enough in practice
-       * and complex enough to support that we don't anticipate supporting anytime soon. Developers
-       * are encouraged to lift classes out of component/hook declarations.
-       */
-      builder.errors.push({
-        reason: 'Inline `class` declarations are not supported',
-        description: `Move class declarations outside of components/hooks`,
-        severity: ErrorSeverity.UnsupportedJS,
-        loc: stmtPath.node.loc ?? null,
-        suggestions: null,
-      });
-      lowerValueToTemporary(builder, {
-        kind: 'UnsupportedNode',
-        loc: stmtPath.node.loc ?? GeneratedSource,
-        node: stmtPath.node,
-      });
-      return;
-    }
-    case 'EnumDeclaration':
-    case 'TSEnumDeclaration': {
-      lowerValueToTemporary(builder, {
-        kind: 'UnsupportedNode',
-        loc: stmtPath.node.loc ?? GeneratedSource,
-        node: stmtPath.node,
-      });
-      return;
-    }
-    case 'ExportAllDeclaration':
-    case 'ExportDefaultDeclaration':
-    case 'ExportNamedDeclaration':
-    case 'ImportDeclaration':
-    case 'TSExportAssignment':
-    case 'TSImportEqualsDeclaration': {
-      builder.errors.push({
-        reason:
-          'JavaScript `import` and `export` statements may only appear at the top level of a module',
-        severity: ErrorSeverity.InvalidJS,
-        loc: stmtPath.node.loc ?? null,
-        suggestions: null,
-      });
-      lowerValueToTemporary(builder, {
-        kind: 'UnsupportedNode',
-        loc: stmtPath.node.loc ?? GeneratedSource,
-        node: stmtPath.node,
-      });
-      return;
-    }
-    case 'TSNamespaceExportDeclaration': {
-      builder.errors.push({
-        reason:
-          'TypeScript `namespace` statements may only appear at the top level of a module',
-        severity: ErrorSeverity.InvalidJS,
-        loc: stmtPath.node.loc ?? null,
-        suggestions: null,
-      });
-      lowerValueToTemporary(builder, {
-        kind: 'UnsupportedNode',
-        loc: stmtPath.node.loc ?? GeneratedSource,
-        node: stmtPath.node,
-      });
+    case 'TypeAlias':
+    case 'TSInterfaceDeclaration':
+    case 'TSTypeAliasDeclaration': {
+      // We do not preserve type annotations/syntax through transformation
       return;
     }
+    case 'ClassDeclaration':
     case 'DeclareClass':
     case 'DeclareExportAllDeclaration':
     case 'DeclareExportDeclaration':
@@ -1462,14 +1365,31 @@ function lowerStatement(
     case 'DeclareOpaqueType':
     case 'DeclareTypeAlias':
     case 'DeclareVariable':
+    case 'EnumDeclaration':
+    case 'ExportAllDeclaration':
+    case 'ExportDefaultDeclaration':
+    case 'ExportNamedDeclaration':
+    case 'ImportDeclaration':
     case 'InterfaceDeclaration':
     case 'OpaqueType':
     case 'TSDeclareFunction':
-    case 'TSInterfaceDeclaration':
+    case 'TSEnumDeclaration':
+    case 'TSExportAssignment':
+    case 'TSImportEqualsDeclaration':
     case 'TSModuleDeclaration':
-    case 'TSTypeAliasDeclaration':
-    case 'TypeAlias': {
-      // We do not preserve type annotations/syntax through transformation
+    case 'TSNamespaceExportDeclaration':
+    case 'WithStatement': {
+      builder.errors.push({
+        reason: `(BuildHIR::lowerStatement) Handle ${stmtPath.type} statements`,
+        severity: ErrorSeverity.Todo,
+        loc: stmtPath.node.loc ?? null,
+        suggestions: null,
+      });
+      lowerValueToTemporary(builder, {
+        kind: 'UnsupportedNode',
+        loc: stmtPath.node.loc ?? GeneratedSource,
+        node: stmtPath.node,
+      });
       return;
     }
     default: {
@@ -1535,11 +1455,6 @@ function lowerObjectPropertyKey(
       kind: 'identifier',
       name: key.node.name,
     };
-  } else if (key.isNumericLiteral()) {
-    return {
-      kind: 'identifier',
-      name: String(key.node.value),
-    };
   }
 
   builder.errors.push({
@@ -1972,7 +1887,6 @@ function lowerExpression(
           place: leftValue,
           loc: exprLoc,
         },
-        effects: null,
         loc: exprLoc,
       });
       builder.terminateWithContinuation(
@@ -2289,17 +2203,11 @@ function lowerExpression(
         });
         for (const [name, locations] of Object.entries(fbtLocations)) {
           if (locations.length > 1) {
-            CompilerError.throwDiagnostic({
-              severity: ErrorSeverity.Todo,
-              category: 'Support duplicate fbt tags',
-              description: `Support \`<${tagName}>\` tags with multiple \`<${tagName}:${name}>\` values`,
-              details: locations.map(loc => {
-                return {
-                  kind: 'error',
-                  message: `Multiple \`<${tagName}:${name}>\` tags found`,
-                  loc,
-                };
-              }),
+            CompilerError.throwTodo({
+              reason: `Support <${tagName}> tags with multiple <${tagName}:${name}> values`,
+              loc: locations.at(-1) ?? GeneratedSource,
+              description: null,
+              suggestions: null,
             });
           }
         }
@@ -2493,19 +2401,6 @@ function lowerExpression(
         kind: 'TypeCastExpression',
         value: lowerExpressionToTemporary(builder, expr.get('expression')),
         typeAnnotation: typeAnnotation.node,
-        typeAnnotationKind: 'cast',
-        type: lowerType(typeAnnotation.node),
-        loc: exprLoc,
-      };
-    }
-    case 'TSSatisfiesExpression': {
-      let expr = exprPath as NodePath<t.TSSatisfiesExpression>;
-      const typeAnnotation = expr.get('typeAnnotation');
-      return {
-        kind: 'TypeCastExpression',
-        value: lowerExpressionToTemporary(builder, expr.get('expression')),
-        typeAnnotation: typeAnnotation.node,
-        typeAnnotationKind: 'satisfies',
         type: lowerType(typeAnnotation.node),
         loc: exprLoc,
       };
@@ -2517,7 +2412,6 @@ function lowerExpression(
         kind: 'TypeCastExpression',
         value: lowerExpressionToTemporary(builder, expr.get('expression')),
         typeAnnotation: typeAnnotation.node,
-        typeAnnotationKind: 'as',
         type: lowerType(typeAnnotation.node),
         loc: exprLoc,
       };
@@ -2914,7 +2808,6 @@ function lowerOptionalCallExpression(
           args,
           loc,
         },
-        effects: null,
         loc,
       });
     } else {
@@ -2928,7 +2821,6 @@ function lowerOptionalCallExpression(
           args,
           loc,
         },
-        effects: null,
         loc,
       });
     }
@@ -3025,8 +2917,6 @@ function isReorderableExpression(
         }
       }
     }
-    case 'TSAsExpression':
-    case 'TSNonNullExpression':
     case 'TypeCastExpression': {
       return isReorderableExpression(
         builder,
@@ -3508,7 +3398,7 @@ function lowerFunction(
     | t.ObjectMethod
   >,
 ): LoweredFunction | null {
-  const componentScope: Scope = builder.environment.parentFunction.scope;
+  const componentScope: Scope = builder.parentFunction.scope;
   const capturedContext = gatherCapturedContext(expr, componentScope);
 
   /*
@@ -3523,12 +3413,14 @@ function lowerFunction(
     expr,
     builder.environment,
     builder.bindings,
-    new Map([...builder.context, ...capturedContext]),
+    [...builder.context, ...capturedContext],
+    builder.parentFunction,
   );
   let loweredFunc: HIRFunction;
   if (lowering.isErr()) {
-    const functionErrors = lowering.unwrapErr();
-    builder.errors.merge(functionErrors);
+    lowering
+      .unwrapErr()
+      .details.forEach(detail => builder.errors.pushErrorDetail(detail));
     return null;
   }
   loweredFunc = lowering.unwrap();
@@ -3545,7 +3437,7 @@ function lowerExpressionToTemporary(
   return lowerValueToTemporary(builder, value);
 }
 
-export function lowerValueToTemporary(
+function lowerValueToTemporary(
   builder: HIRBuilder,
   value: InstructionValue,
 ): Place {
@@ -3555,10 +3447,9 @@ export function lowerValueToTemporary(
   const place: Place = buildTemporaryPlace(builder, value.loc);
   builder.push({
     id: makeInstructionId(0),
-    lvalue: {...place},
     value: value,
-    effects: null,
     loc: value.loc,
+    lvalue: {...place},
   });
   return place;
 }
@@ -3582,16 +3473,6 @@ function lowerIdentifier(
       return place;
     }
     default: {
-      if (binding.kind === 'Global' && binding.name === 'eval') {
-        builder.errors.push({
-          reason: `The 'eval' function is not supported`,
-          description:
-            'Eval is an anti-pattern in JavaScript, and the code executed cannot be evaluated by React Compiler',
-          severity: ErrorSeverity.UnsupportedJS,
-          loc: exprPath.node.loc ?? null,
-          suggestions: null,
-        });
-      }
       return lowerValueToTemporary(builder, {
         kind: 'LoadGlobal',
         binding,
@@ -3709,40 +3590,31 @@ function lowerAssignment(
 
       let temporary;
       if (builder.isContextIdentifier(lvalue)) {
-        if (kind === InstructionKind.Const && !isHoistedIdentifier) {
-          builder.errors.push({
-            reason: `Expected \`const\` declaration not to be reassigned`,
-            severity: ErrorSeverity.InvalidJS,
-            loc: lvalue.node.loc ?? null,
-            suggestions: null,
+        if (kind !== InstructionKind.Reassign && !isHoistedIdentifier) {
+          if (kind === InstructionKind.Const) {
+            builder.errors.push({
+              reason: `Expected \`const\` declaration not to be reassigned`,
+              severity: ErrorSeverity.InvalidJS,
+              loc: lvalue.node.loc ?? null,
+              suggestions: null,
+            });
+          }
+          lowerValueToTemporary(builder, {
+            kind: 'DeclareContext',
+            lvalue: {
+              kind: InstructionKind.Let,
+              place: {...place},
+            },
+            loc: place.loc,
           });
         }
 
-        if (
-          kind !== InstructionKind.Const &&
-          kind !== InstructionKind.Reassign &&
-          kind !== InstructionKind.Let &&
-          kind !== InstructionKind.Function
-        ) {
-          builder.errors.push({
-            reason: `Unexpected context variable kind`,
-            severity: ErrorSeverity.InvalidJS,
-            loc: lvalue.node.loc ?? null,
-            suggestions: null,
-          });
-          temporary = lowerValueToTemporary(builder, {
-            kind: 'UnsupportedNode',
-            node: lvalueNode,
-            loc: lvalueNode.loc ?? GeneratedSource,
-          });
-        } else {
-          temporary = lowerValueToTemporary(builder, {
-            kind: 'StoreContext',
-            lvalue: {place: {...place}, kind},
-            value,
-            loc,
-          });
-        }
+        temporary = lowerValueToTemporary(builder, {
+          kind: 'StoreContext',
+          lvalue: {place: {...place}, kind: InstructionKind.Reassign},
+          value,
+          loc,
+        });
       } else {
         const typeAnnotation = lvalue.get('typeAnnotation');
         let type: t.FlowType | t.TSType | null;
@@ -4251,11 +4123,6 @@ function captureScopes({from, to}: {from: Scope; to: Scope}): Set<Scope> {
   return scopes;
 }
 
-/**
- * Returns a mapping of "context" identifiers — references to free variables that
- * will become part of the function expression's `context` array — along with the
- * source location of their first reference within the function.
- */
 function gatherCapturedContext(
   fn: NodePath<
     | t.FunctionExpression
@@ -4264,8 +4131,8 @@ function gatherCapturedContext(
     | t.ObjectMethod
   >,
   componentScope: Scope,
-): Map<t.Identifier, SourceLocation> {
-  const capturedIds = new Map<t.Identifier, SourceLocation>();
+): Array<t.Identifier> {
+  const capturedIds = new Set<t.Identifier>();
 
   /*
    * Capture all the scopes from the parent of this function up to and including
@@ -4308,15 +4175,8 @@ function gatherCapturedContext(
 
     // Add the base identifier binding as a dependency.
     const binding = baseIdentifier.scope.getBinding(baseIdentifier.node.name);
-    if (
-      binding !== undefined &&
-      pureScopes.has(binding.scope) &&
-      !capturedIds.has(binding.identifier)
-    ) {
-      capturedIds.set(
-        binding.identifier,
-        path.node.loc ?? binding.identifier.loc ?? GeneratedSource,
-      );
+    if (binding !== undefined && pureScopes.has(binding.scope)) {
+      capturedIds.add(binding.identifier);
     }
   }
 
@@ -4353,7 +4213,7 @@ function gatherCapturedContext(
     },
   });
 
-  return capturedIds;
+  return [...capturedIds.keys()];
 }
 
 function notNull<T>(value: T | null): value is T {

compiler/packages/babel-plugin-react-compiler/src/HIR/BuildReactiveScopeTerminalsHIR.ts

@@ -1,10 +1,3 @@
-/**
- * Copyright (c) Meta Platforms, Inc. and affiliates.
- *
- * This source code is licensed under the MIT license found in the
- * LICENSE file in the root directory of this source tree.
- */
-
 import {CompilerError} from '../CompilerError';
 import {getScopes, recursivelyTraverseItems} from './AssertValidBlockNesting';
 import {Environment} from './Environment';

compiler/packages/babel-plugin-react-compiler/src/HIR/CollectHoistablePropertyLoads.ts

@@ -1,10 +1,3 @@
-/**
- * Copyright (c) Meta Platforms, Inc. and affiliates.
- *
- * This source code is licensed under the MIT license found in the
- * LICENSE file in the root directory of this source tree.
- */
-
 import {CompilerError} from '../CompilerError';
 import {inRange} from '../ReactiveScopes/InferReactiveScopeVariables';
 import {printDependency} from '../ReactiveScopes/PrintReactiveFunction';
@@ -19,19 +12,15 @@ import {
   BasicBlock,
   BlockId,
   DependencyPathEntry,
-  FunctionExpression,
   GeneratedSource,
-  getHookKind,
   HIRFunction,
   Identifier,
   IdentifierId,
   InstructionId,
   InstructionValue,
-  LoweredFunction,
   PropertyLiteral,
   ReactiveScopeDependency,
   ScopeId,
-  TInstruction,
 } from './HIR';
 
 const DEBUG_PRINT = false;
@@ -123,39 +112,9 @@ export function collectHoistablePropertyLoads(
     hoistableFromOptionals,
     registry,
     nestedFnImmutableContext: null,
-    assumedInvokedFns: fn.env.config.enableTreatFunctionDepsAsConditional
-      ? new Set()
-      : getAssumedInvokedFunctions(fn),
   });
 }
 
-export function collectHoistablePropertyLoadsInInnerFn(
-  fnInstr: TInstruction<FunctionExpression>,
-  temporaries: ReadonlyMap<IdentifierId, ReactiveScopeDependency>,
-  hoistableFromOptionals: ReadonlyMap<BlockId, ReactiveScopeDependency>,
-): ReadonlyMap<BlockId, BlockInfo> {
-  const fn = fnInstr.value.loweredFunc.func;
-  const initialContext: CollectHoistablePropertyLoadsContext = {
-    temporaries,
-    knownImmutableIdentifiers: new Set(),
-    hoistableFromOptionals,
-    registry: new PropertyPathRegistry(),
-    nestedFnImmutableContext: null,
-    assumedInvokedFns: fn.env.config.enableTreatFunctionDepsAsConditional
-      ? new Set()
-      : getAssumedInvokedFunctions(fn),
-  };
-  const nestedFnImmutableContext = new Set(
-    fn.context
-      .filter(place =>
-        isImmutableAtInstr(place.identifier, fnInstr.id, initialContext),
-      )
-      .map(place => place.identifier.id),
-  );
-  initialContext.nestedFnImmutableContext = nestedFnImmutableContext;
-  return collectHoistablePropertyLoadsImpl(fn, initialContext);
-}
-
 type CollectHoistablePropertyLoadsContext = {
   temporaries: ReadonlyMap<IdentifierId, ReactiveScopeDependency>;
   knownImmutableIdentifiers: ReadonlySet<IdentifierId>;
@@ -168,11 +127,6 @@ type CollectHoistablePropertyLoadsContext = {
    * but are currently kept separate for readability.
    */
   nestedFnImmutableContext: ReadonlySet<IdentifierId> | null;
-  /**
-   * Functions which are assumed to be eventually called (as opposed to ones which might
-   * not be called, e.g. the 0th argument of Array.map)
-   */
-  assumedInvokedFns: ReadonlySet<LoweredFunction>;
 };
 function collectHoistablePropertyLoadsImpl(
   fn: HIRFunction,
@@ -241,10 +195,7 @@ type PropertyPathNode =
 class PropertyPathRegistry {
   roots: Map<IdentifierId, RootNode> = new Map();
 
-  getOrCreateIdentifier(
-    identifier: Identifier,
-    reactive: boolean,
-  ): PropertyPathNode {
+  getOrCreateIdentifier(identifier: Identifier): PropertyPathNode {
     /**
      * Reads from a statically scoped variable are always safe in JS,
      * with the exception of TDZ (not addressed by this pass).
@@ -258,19 +209,12 @@ class PropertyPathRegistry {
         optionalProperties: new Map(),
         fullPath: {
           identifier,
-          reactive,
           path: [],
         },
         hasOptional: false,
         parent: null,
       };
       this.roots.set(identifier.id, rootNode);
-    } else {
-      CompilerError.invariant(reactive === rootNode.fullPath.reactive, {
-        reason:
-          '[HoistablePropertyLoads] Found inconsistencies in `reactive` flag when deduping identifier reads within the same scope',
-        loc: identifier.loc,
-      });
     }
     return rootNode;
   }
@@ -288,7 +232,6 @@ class PropertyPathRegistry {
         parent: parent,
         fullPath: {
           identifier: parent.fullPath.identifier,
-          reactive: parent.fullPath.reactive,
           path: parent.fullPath.path.concat(entry),
         },
         hasOptional: parent.hasOptional || entry.optional,
@@ -304,7 +247,7 @@ class PropertyPathRegistry {
      * so all subpaths of a PropertyLoad should already exist
      * (e.g. a.b is added before a.b.c),
      */
-    let currNode = this.getOrCreateIdentifier(n.identifier, n.reactive);
+    let currNode = this.getOrCreateIdentifier(n.identifier);
     if (n.path.length === 0) {
       return currNode;
     }
@@ -326,11 +269,10 @@ function getMaybeNonNullInInstruction(
   instr: InstructionValue,
   context: CollectHoistablePropertyLoadsContext,
 ): PropertyPathNode | null {
-  let path: ReactiveScopeDependency | null = null;
+  let path = null;
   if (instr.kind === 'PropertyLoad') {
     path = context.temporaries.get(instr.object.identifier.id) ?? {
       identifier: instr.object.identifier,
-      reactive: instr.object.reactive,
       path: [],
     };
   } else if (instr.kind === 'Destructure') {
@@ -393,16 +335,10 @@ function collectNonNullsInBlocks(
   ) {
     const identifier = fn.params[0].identifier;
     knownNonNullIdentifiers.add(
-      context.registry.getOrCreateIdentifier(identifier, true),
+      context.registry.getOrCreateIdentifier(identifier),
     );
   }
-  const nodes = new Map<
-    BlockId,
-    {
-      block: BasicBlock;
-      assumedNonNullObjects: Set<PropertyPathNode>;
-    }
-  >();
+  const nodes = new Map<BlockId, BlockInfo>();
   for (const [_, block] of fn.body.blocks) {
     const assumedNonNullObjects = new Set<PropertyPathNode>(
       knownNonNullIdentifiers,
@@ -422,30 +358,32 @@ function collectNonNullsInBlocks(
       ) {
         assumedNonNullObjects.add(maybeNonNull);
       }
-      if (instr.value.kind === 'FunctionExpression') {
+      if (
+        (instr.value.kind === 'FunctionExpression' ||
+          instr.value.kind === 'ObjectMethod') &&
+        !fn.env.config.enableTreatFunctionDepsAsConditional
+      ) {
         const innerFn = instr.value.loweredFunc;
-        if (context.assumedInvokedFns.has(innerFn)) {
-          const innerHoistableMap = collectHoistablePropertyLoadsImpl(
-            innerFn.func,
-            {
-              ...context,
-              nestedFnImmutableContext:
-                context.nestedFnImmutableContext ??
-                new Set(
-                  innerFn.func.context
-                    .filter(place =>
-                      isImmutableAtInstr(place.identifier, instr.id, context),
-                    )
-                    .map(place => place.identifier.id),
-                ),
-            },
-          );
-          const innerHoistables = assertNonNull(
-            innerHoistableMap.get(innerFn.func.body.entry),
-          );
-          for (const entry of innerHoistables.assumedNonNullObjects) {
-            assumedNonNullObjects.add(entry);
-          }
+        const innerHoistableMap = collectHoistablePropertyLoadsImpl(
+          innerFn.func,
+          {
+            ...context,
+            nestedFnImmutableContext:
+              context.nestedFnImmutableContext ??
+              new Set(
+                innerFn.func.context
+                  .filter(place =>
+                    isImmutableAtInstr(place.identifier, instr.id, context),
+                  )
+                  .map(place => place.identifier.id),
+              ),
+          },
+        );
+        const innerHoistables = assertNonNull(
+          innerHoistableMap.get(innerFn.func.body.entry),
+        );
+        for (const entry of innerHoistables.assumedNonNullObjects) {
+          assumedNonNullObjects.add(entry);
         }
       }
     }
@@ -628,11 +566,9 @@ function reduceMaybeOptionalChains(
     changed = false;
 
     for (const original of optionalChainNodes) {
-      let {identifier, path: origPath, reactive} = original.fullPath;
-      let currNode: PropertyPathNode = registry.getOrCreateIdentifier(
-        identifier,
-        reactive,
-      );
+      let {identifier, path: origPath} = original.fullPath;
+      let currNode: PropertyPathNode =
+        registry.getOrCreateIdentifier(identifier);
       for (let i = 0; i < origPath.length; i++) {
         const entry = origPath[i];
         // If the base is known to be non-null, replace with a non-optional load
@@ -655,130 +591,3 @@ function reduceMaybeOptionalChains(
     }
   } while (changed);
 }
-
-function getAssumedInvokedFunctions(
-  fn: HIRFunction,
-  temporaries: Map<
-    IdentifierId,
-    {fn: LoweredFunction; mayInvoke: Set<LoweredFunction>}
-  > = new Map(),
-): ReadonlySet<LoweredFunction> {
-  const hoistableFunctions = new Set<LoweredFunction>();
-  /**
-   * Step 1: Conservatively collect identifier to function expression mappings
-   */
-  for (const block of fn.body.blocks.values()) {
-    for (const {lvalue, value} of block.instructions) {
-      /**
-       * Conservatively only match function expressions which can have guaranteed ssa.
-       * ObjectMethods and ObjectProperties do not.
-       */
-      if (value.kind === 'FunctionExpression') {
-        temporaries.set(lvalue.identifier.id, {
-          fn: value.loweredFunc,
-          mayInvoke: new Set(),
-        });
-      } else if (value.kind === 'StoreLocal') {
-        const lvalue = value.lvalue.place.identifier;
-        const maybeLoweredFunc = temporaries.get(value.value.identifier.id);
-        if (maybeLoweredFunc != null) {
-          temporaries.set(lvalue.id, maybeLoweredFunc);
-        }
-      } else if (value.kind === 'LoadLocal') {
-        const maybeLoweredFunc = temporaries.get(value.place.identifier.id);
-        if (maybeLoweredFunc != null) {
-          temporaries.set(lvalue.identifier.id, maybeLoweredFunc);
-        }
-      }
-    }
-  }
-  /**
-   * Step 2: Forward pass to do analysis of assumed function calls. Note that
-   * this is conservative and does not count indirect references through
-   * containers (e.g. `return {cb: () => {...}})`).
-   */
-  for (const block of fn.body.blocks.values()) {
-    for (const {lvalue, value} of block.instructions) {
-      if (value.kind === 'CallExpression') {
-        const callee = value.callee;
-        const maybeHook = getHookKind(fn.env, callee.identifier);
-        const maybeLoweredFunc = temporaries.get(callee.identifier.id);
-        if (maybeLoweredFunc != null) {
-          // Direct calls
-          hoistableFunctions.add(maybeLoweredFunc.fn);
-        } else if (maybeHook != null) {
-          /**
-           * Assume arguments to all hooks are safe to invoke
-           */
-          for (const arg of value.args) {
-            if (arg.kind === 'Identifier') {
-              const maybeLoweredFunc = temporaries.get(arg.identifier.id);
-              if (maybeLoweredFunc != null) {
-                hoistableFunctions.add(maybeLoweredFunc.fn);
-              }
-            }
-          }
-        }
-      } else if (value.kind === 'JsxExpression') {
-        /**
-         * Assume JSX attributes and children are safe to invoke
-         */
-        for (const attr of value.props) {
-          if (attr.kind === 'JsxSpreadAttribute') {
-            continue;
-          }
-          const maybeLoweredFunc = temporaries.get(attr.place.identifier.id);
-          if (maybeLoweredFunc != null) {
-            hoistableFunctions.add(maybeLoweredFunc.fn);
-          }
-        }
-        for (const child of value.children ?? []) {
-          const maybeLoweredFunc = temporaries.get(child.identifier.id);
-          if (maybeLoweredFunc != null) {
-            hoistableFunctions.add(maybeLoweredFunc.fn);
-          }
-        }
-      } else if (value.kind === 'FunctionExpression') {
-        /**
-         * Recursively traverse into other function expressions which may invoke
-         * or pass already declared functions to react (e.g. as JSXAttributes).
-         *
-         * If lambda A calls lambda B, we assume lambda B is safe to invoke if
-         * lambda A is -- even if lambda B is conditionally called. (see
-         * `conditional-call-chain` fixture for example).
-         */
-        const loweredFunc = value.loweredFunc.func;
-        const lambdasCalled = getAssumedInvokedFunctions(
-          loweredFunc,
-          temporaries,
-        );
-        const maybeLoweredFunc = temporaries.get(lvalue.identifier.id);
-        if (maybeLoweredFunc != null) {
-          for (const called of lambdasCalled) {
-            maybeLoweredFunc.mayInvoke.add(called);
-          }
-        }
-      }
-    }
-    if (block.terminal.kind === 'return') {
-      /**
-       * Assume directly returned functions are safe to call
-       */
-      const maybeLoweredFunc = temporaries.get(
-        block.terminal.value.identifier.id,
-      );
-      if (maybeLoweredFunc != null) {
-        hoistableFunctions.add(maybeLoweredFunc.fn);
-      }
-    }
-  }
-
-  for (const [_, {fn, mayInvoke}] of temporaries) {
-    if (hoistableFunctions.has(fn)) {
-      for (const called of mayInvoke) {
-        hoistableFunctions.add(called);
-      }
-    }
-  }
-  return hoistableFunctions;
-}

compiler/packages/babel-plugin-react-compiler/src/HIR/CollectOptionalChainDependencies.ts

@@ -1,10 +1,3 @@
-/**
- * Copyright (c) Meta Platforms, Inc. and affiliates.
- *
- * This source code is licensed under the MIT license found in the
- * LICENSE file in the root directory of this source tree.
- */
-
 import {CompilerError} from '..';
 import {assertNonNull} from './CollectHoistablePropertyLoads';
 import {
@@ -290,7 +283,6 @@ function traverseOptionalBlock(
     );
     baseObject = {
       identifier: maybeTest.instructions[0].value.place.identifier,
-      reactive: maybeTest.instructions[0].value.place.reactive,
       path,
     };
     test = maybeTest.terminal;
@@ -392,7 +384,6 @@ function traverseOptionalBlock(
   );
   const load = {
     identifier: baseObject.identifier,
-    reactive: baseObject.reactive,
     path: [
       ...baseObject.path,
       {

compiler/packages/babel-plugin-react-compiler/src/HIR/DeriveMinimalDependenciesHIR.ts

@@ -25,9 +25,8 @@ export class ReactiveScopeDependencyTreeHIR {
    * `identifier.path`, or `identifier?.path` is in this map, it is safe to
    * evaluate (non-optional) PropertyLoads from.
    */
-  #hoistableObjects: Map<Identifier, HoistableNode & {reactive: boolean}> =
-    new Map();
-  #deps: Map<Identifier, DependencyNode & {reactive: boolean}> = new Map();
+  #hoistableObjects: Map<Identifier, HoistableNode> = new Map();
+  #deps: Map<Identifier, DependencyNode> = new Map();
 
   /**
    * @param hoistableObjects a set of paths from which we can safely evaluate
@@ -36,10 +35,9 @@ export class ReactiveScopeDependencyTreeHIR {
    * duplicates when traversing the CFG.
    */
   constructor(hoistableObjects: Iterable<ReactiveScopeDependency>) {
-    for (const {path, identifier, reactive} of hoistableObjects) {
+    for (const {path, identifier} of hoistableObjects) {
       let currNode = ReactiveScopeDependencyTreeHIR.#getOrCreateRoot(
         identifier,
-        reactive,
         this.#hoistableObjects,
         path.length > 0 && path[0].optional ? 'Optional' : 'NonNull',
       );
@@ -72,8 +70,7 @@ export class ReactiveScopeDependencyTreeHIR {
 
   static #getOrCreateRoot<T extends string>(
     identifier: Identifier,
-    reactive: boolean,
-    roots: Map<Identifier, TreeNode<T> & {reactive: boolean}>,
+    roots: Map<Identifier, TreeNode<T>>,
     defaultAccessType: T,
   ): TreeNode<T> {
     // roots can always be accessed unconditionally in JS
@@ -82,16 +79,9 @@ export class ReactiveScopeDependencyTreeHIR {
     if (rootNode === undefined) {
       rootNode = {
         properties: new Map(),
-        reactive,
         accessType: defaultAccessType,
       };
       roots.set(identifier, rootNode);
-    } else {
-      CompilerError.invariant(reactive === rootNode.reactive, {
-        reason: '[DeriveMinimalDependenciesHIR] Conflicting reactive root flag',
-        description: `Identifier ${printIdentifier(identifier)}`,
-        loc: GeneratedSource,
-      });
     }
     return rootNode;
   }
@@ -102,10 +92,9 @@ export class ReactiveScopeDependencyTreeHIR {
    * safe-to-evaluate subpath
    */
   addDependency(dep: ReactiveScopeDependency): void {
-    const {identifier, reactive, path} = dep;
+    const {identifier, path} = dep;
     let depCursor = ReactiveScopeDependencyTreeHIR.#getOrCreateRoot(
       identifier,
-      reactive,
       this.#deps,
       PropertyAccessType.UnconditionalAccess,
     );
@@ -183,13 +172,7 @@ export class ReactiveScopeDependencyTreeHIR {
   deriveMinimalDependencies(): Set<ReactiveScopeDependency> {
     const results = new Set<ReactiveScopeDependency>();
     for (const [rootId, rootNode] of this.#deps.entries()) {
-      collectMinimalDependenciesInSubtree(
-        rootNode,
-        rootNode.reactive,
-        rootId,
-        [],
-        results,
-      );
+      collectMinimalDependenciesInSubtree(rootNode, rootId, [], results);
     }
 
     return results;
@@ -311,24 +294,25 @@ type HoistableNode = TreeNode<'Optional' | 'NonNull'>;
 type DependencyNode = TreeNode<PropertyAccessType>;
 
 /**
+ * TODO: this is directly pasted from DeriveMinimalDependencies. Since we no
+ * longer have conditionally accessed nodes, we can simplify
+ *
  * Recursively calculates minimal dependencies in a subtree.
  * @param node DependencyNode representing a dependency subtree.
  * @returns a minimal list of dependencies in this subtree.
  */
 function collectMinimalDependenciesInSubtree(
   node: DependencyNode,
-  reactive: boolean,
   rootIdentifier: Identifier,
   path: Array<DependencyPathEntry>,
   results: Set<ReactiveScopeDependency>,
 ): void {
   if (isDependency(node.accessType)) {
-    results.add({identifier: rootIdentifier, reactive, path});
+    results.add({identifier: rootIdentifier, path});
   } else {
     for (const [childName, childNode] of node.properties) {
       collectMinimalDependenciesInSubtree(
         childNode,
-        reactive,
         rootIdentifier,
         [
           ...path,

compiler/packages/babel-plugin-react-compiler/src/HIR/Environment.ts

@@ -9,7 +9,13 @@ import * as t from '@babel/types';
 import {ZodError, z} from 'zod';
 import {fromZodError} from 'zod-validation-error';
 import {CompilerError} from '../CompilerError';
-import {Logger, ProgramContext} from '../Entrypoint';
+import {
+  CompilationMode,
+  Logger,
+  PanicThresholdOptions,
+  parsePluginOptions,
+  PluginOptions,
+} from '../Entrypoint';
 import {Err, Ok, Result} from '../Utils/Result';
 import {
   DEFAULT_GLOBALS,
@@ -47,7 +53,7 @@ import {
   ShapeRegistry,
   addHook,
 } from './ObjectShape';
-import {Scope as BabelScope, NodePath} from '@babel/traverse';
+import {Scope as BabelScope} from '@babel/traverse';
 import {TypeSchema} from './TypeSchema';
 
 export const ReactElementSymbolSchema = z.object({
@@ -78,8 +84,6 @@ export const InstrumentationSchema = z
   );
 
 export type ExternalFunction = z.infer<typeof ExternalFunctionSchema>;
-export const USE_FIRE_FUNCTION_NAME = 'useFire';
-export const EMIT_FREEZE_GLOBAL_GATING = '__DEV__';
 
 export const MacroMethodSchema = z.union([
   z.object({type: z.literal('wildcard')}),
@@ -92,8 +96,6 @@ export const MacroSchema = z.union([
   z.tuple([z.string(), z.array(MacroMethodSchema)]),
 ]);
 
-export type CompilerMode = 'all_features' | 'no_inferred_memo';
-
 export type Macro = z.infer<typeof MacroSchema>;
 export type MacroMethod = z.infer<typeof MacroMethodSchema>;
 
@@ -150,7 +152,7 @@ export type Hook = z.infer<typeof HookSchema>;
  *   missing some recursive Object / Function shapeIds
  */
 
-export const EnvironmentConfigSchema = z.object({
+const EnvironmentConfigSchema = z.object({
   customHooks: z.map(z.string(), HookSchema).default(new Map()),
 
   /**
@@ -243,11 +245,6 @@ export const EnvironmentConfigSchema = z.object({
    */
   enableUseTypeAnnotations: z.boolean().default(false),
 
-  /**
-   * Enable a new model for mutability and aliasing inference
-   */
-  enableNewMutationAliasingModel: z.boolean().default(true),
-
   /**
    * Enables inference of optional dependency chains. Without this flag
    * a property chain such as `props?.items?.foo` will infer as a dep on
@@ -265,19 +262,21 @@ export const EnvironmentConfigSchema = z.object({
    *   {
    *     module: 'react',
    *     imported: 'useEffect',
-   *     autodepsIndex: 1,
+   *     numRequiredArgs: 1,
    *   },{
    *     module: 'MyExperimentalEffectHooks',
    *     imported: 'useExperimentalEffect',
-   *     autodepsIndex: 2,
+   *     numRequiredArgs: 2,
    *   },
    * ]
    * would insert dependencies for calls of `useEffect` imported from `react` and calls of
    * useExperimentalEffect` from `MyExperimentalEffectHooks`.
    *
-   * `autodepsIndex` tells the compiler which index we expect the AUTODEPS to appear in.
-   *  With the configuration above, we'd insert dependencies for `useEffect` if it has two
-   *  arguments, and the second is AUTODEPS.
+   * `numRequiredArgs` tells the compiler the amount of arguments required to append a dependency
+   *  array to the end of the call. With the configuration above, we'd insert dependencies for
+   *  `useEffect` if it is only given a single argument and it would be appended to the argument list.
+   *
+   * numRequiredArgs must always be greater than 0, otherwise there is no function to analyze for dependencies
    *
    * Still experimental.
    */
@@ -286,7 +285,7 @@ export const EnvironmentConfigSchema = z.object({
       z.array(
         z.object({
           function: ExternalFunctionSchema,
-          autodepsIndex: z.number().min(1, 'autodepsIndex must be > 0'),
+          numRequiredArgs: z.number().min(1, 'numRequiredArgs must be > 0'),
         }),
       ),
     )
@@ -318,10 +317,10 @@ export const EnvironmentConfigSchema = z.object({
   validateNoSetStateInRender: z.boolean().default(true),
 
   /**
-   * Validates that setState is not called synchronously within an effect (useEffect and friends).
+   * Validates that setState is not called directly within a passive effect (useEffect).
    * Scheduling a setState (with an event listener, subscription, etc) is valid.
    */
-  validateNoSetStateInEffects: z.boolean().default(false),
+  validateNoSetStateInPassiveEffects: z.boolean().default(false),
 
   /**
    * Validates against creating JSX within a try block and recommends using an error boundary
@@ -329,11 +328,6 @@ export const EnvironmentConfigSchema = z.object({
    */
   validateNoJSXInTryStatements: z.boolean().default(false),
 
-  /**
-   * Validates against dynamically creating components during render.
-   */
-  validateStaticComponents: z.boolean().default(false),
-
   /**
    * Validates that the dependencies of all effect hooks are memoized. This helps ensure
    * that Forget does not introduce infinite renders caused by a dependency changing,
@@ -362,11 +356,6 @@ export const EnvironmentConfigSchema = z.object({
    */
   validateNoImpureFunctionsInRender: z.boolean().default(false),
 
-  /**
-   * Validate against passing mutable functions to hooks
-   */
-  validateNoFreezingKnownMutableFunctions: z.boolean().default(false),
-
   /*
    * When enabled, the compiler assumes that hooks follow the Rules of React:
    * - Hooks may memoize computation based on any of their parameters, thus
@@ -561,6 +550,8 @@ export const EnvironmentConfigSchema = z.object({
    */
   disableMemoizationForDebugging: z.boolean().default(false),
 
+  enableMinimalTransformsForRetry: z.boolean().default(false),
+
   /**
    * When true, rather using memoized values, the compiler will always re-compute
    * values, and then use a heuristic to compare the memoized value to the newly
@@ -631,21 +622,200 @@ export const EnvironmentConfigSchema = z.object({
    * ```
    */
   lowerContextAccess: ExternalFunctionSchema.nullable().default(null),
-
-  /**
-   * If enabled, will validate useMemos that don't return any values:
-   *
-   * Valid:
-   *   useMemo(() => foo, [foo]);
-   *   useMemo(() => { return foo }, [foo]);
-   * Invalid:
-   *   useMemo(() => { ... }, [...]);
-   */
-  validateNoVoidUseMemo: z.boolean().default(false),
 });
 
 export type EnvironmentConfig = z.infer<typeof EnvironmentConfigSchema>;
 
+export const MINIMAL_RETRY_CONFIG: PartialEnvironmentConfig = {
+  validateHooksUsage: false,
+  validateRefAccessDuringRender: false,
+  validateNoSetStateInRender: false,
+  validateNoSetStateInPassiveEffects: false,
+  validateNoJSXInTryStatements: false,
+  validateMemoizedEffectDependencies: false,
+  validateNoCapitalizedCalls: null,
+  validateBlocklistedImports: null,
+  enableMinimalTransformsForRetry: true,
+};
+/**
+ * For test fixtures and playground only.
+ *
+ * Pragmas are straightforward to parse for boolean options (`:true` and
+ * `:false`). These are 'enabled' config values for non-boolean configs (i.e.
+ * what is used when parsing `:true`).
+ */
+const testComplexConfigDefaults: PartialEnvironmentConfig = {
+  validateNoCapitalizedCalls: [],
+  enableChangeDetectionForDebugging: {
+    source: 'react-compiler-runtime',
+    importSpecifierName: '$structuralCheck',
+  },
+  enableEmitFreeze: {
+    source: 'react-compiler-runtime',
+    importSpecifierName: 'makeReadOnly',
+  },
+  enableEmitInstrumentForget: {
+    fn: {
+      source: 'react-compiler-runtime',
+      importSpecifierName: 'useRenderCounter',
+    },
+    gating: {
+      source: 'react-compiler-runtime',
+      importSpecifierName: 'shouldInstrument',
+    },
+    globalGating: '__DEV__',
+  },
+  enableEmitHookGuards: {
+    source: 'react-compiler-runtime',
+    importSpecifierName: '$dispatcherGuard',
+  },
+  inlineJsxTransform: {
+    elementSymbol: 'react.transitional.element',
+    globalDevVar: 'DEV',
+  },
+  lowerContextAccess: {
+    source: 'react-compiler-runtime',
+    importSpecifierName: 'useContext_withSelector',
+  },
+  inferEffectDependencies: [
+    {
+      function: {
+        source: 'react',
+        importSpecifierName: 'useEffect',
+      },
+      numRequiredArgs: 1,
+    },
+    {
+      function: {
+        source: 'shared-runtime',
+        importSpecifierName: 'useSpecialEffect',
+      },
+      numRequiredArgs: 2,
+    },
+    {
+      function: {
+        source: 'useEffectWrapper',
+        importSpecifierName: 'default',
+      },
+      numRequiredArgs: 1,
+    },
+  ],
+};
+
+/**
+ * For snap test fixtures and playground only.
+ */
+function parseConfigPragmaEnvironmentForTest(
+  pragma: string,
+): EnvironmentConfig {
+  const maybeConfig: any = {};
+  // Get the defaults to programmatically check for boolean properties
+  const defaultConfig = EnvironmentConfigSchema.parse({});
+
+  for (const token of pragma.split(' ')) {
+    if (!token.startsWith('@')) {
+      continue;
+    }
+    const keyVal = token.slice(1);
+    let [key, val = undefined] = keyVal.split(':');
+    const isSet = val === undefined || val === 'true';
+
+    if (isSet && key in testComplexConfigDefaults) {
+      maybeConfig[key] =
+        testComplexConfigDefaults[key as keyof PartialEnvironmentConfig];
+      continue;
+    }
+
+    if (key === 'customMacros' && val) {
+      const valSplit = val.split('.');
+      if (valSplit.length > 0) {
+        const props = [];
+        for (const elt of valSplit.slice(1)) {
+          if (elt === '*') {
+            props.push({type: 'wildcard'});
+          } else if (elt.length > 0) {
+            props.push({type: 'name', name: elt});
+          }
+        }
+        maybeConfig[key] = [[valSplit[0], props]];
+      }
+      continue;
+    }
+
+    if (
+      key !== 'enableResetCacheOnSourceFileChanges' &&
+      typeof defaultConfig[key as keyof EnvironmentConfig] !== 'boolean'
+    ) {
+      // skip parsing non-boolean properties
+      continue;
+    }
+    if (val === undefined || val === 'true') {
+      maybeConfig[key] = true;
+    } else {
+      maybeConfig[key] = false;
+    }
+  }
+  const config = EnvironmentConfigSchema.safeParse(maybeConfig);
+  if (config.success) {
+    /**
+     * Unless explicitly enabled, do not insert HMR handling code
+     * in test fixtures or playground to reduce visual noise.
+     */
+    if (config.data.enableResetCacheOnSourceFileChanges == null) {
+      config.data.enableResetCacheOnSourceFileChanges = false;
+    }
+    return config.data;
+  }
+  CompilerError.invariant(false, {
+    reason: 'Internal error, could not parse config from pragma string',
+    description: `${fromZodError(config.error)}`,
+    loc: null,
+    suggestions: null,
+  });
+}
+export function parseConfigPragmaForTests(
+  pragma: string,
+  defaults: {
+    compilationMode: CompilationMode;
+  },
+): PluginOptions {
+  const environment = parseConfigPragmaEnvironmentForTest(pragma);
+  let compilationMode: CompilationMode = defaults.compilationMode;
+  let panicThreshold: PanicThresholdOptions = 'all_errors';
+  for (const token of pragma.split(' ')) {
+    if (!token.startsWith('@')) {
+      continue;
+    }
+    switch (token) {
+      case '@compilationMode(annotation)': {
+        compilationMode = 'annotation';
+        break;
+      }
+      case '@compilationMode(infer)': {
+        compilationMode = 'infer';
+        break;
+      }
+      case '@compilationMode(all)': {
+        compilationMode = 'all';
+        break;
+      }
+      case '@compilationMode(syntax)': {
+        compilationMode = 'syntax';
+        break;
+      }
+      case '@panicThreshold(none)': {
+        panicThreshold = 'none';
+        break;
+      }
+    }
+  }
+  return parsePluginOptions({
+    environment,
+    compilationMode,
+    panicThreshold,
+  });
+}
+
 export type PartialEnvironmentConfig = Partial<EnvironmentConfig>;
 
 export type ReactFunctionType = 'Component' | 'Hook' | 'Other';
@@ -681,40 +851,34 @@ export class Environment {
   code: string | null;
   config: EnvironmentConfig;
   fnType: ReactFunctionType;
-  compilerMode: CompilerMode;
-  programContext: ProgramContext;
+  useMemoCacheIdentifier: string;
+  hasLoweredContextAccess: boolean;
   hasFireRewrite: boolean;
-  hasInferredEffect: boolean;
-  inferredEffectLocations: Set<SourceLocation> = new Set();
 
   #contextIdentifiers: Set<t.Identifier>;
   #hoistedIdentifiers: Set<t.Identifier>;
-  parentFunction: NodePath<t.Function>;
 
   constructor(
     scope: BabelScope,
     fnType: ReactFunctionType,
-    compilerMode: CompilerMode,
     config: EnvironmentConfig,
     contextIdentifiers: Set<t.Identifier>,
-    parentFunction: NodePath<t.Function>, // the outermost function being compiled
     logger: Logger | null,
     filename: string | null,
     code: string | null,
-    programContext: ProgramContext,
+    useMemoCacheIdentifier: string,
   ) {
     this.#scope = scope;
     this.fnType = fnType;
-    this.compilerMode = compilerMode;
     this.config = config;
     this.filename = filename;
     this.code = code;
     this.logger = logger;
-    this.programContext = programContext;
+    this.useMemoCacheIdentifier = useMemoCacheIdentifier;
     this.#shapes = new Map(DEFAULT_SHAPES);
     this.#globals = new Map(DEFAULT_GLOBALS);
+    this.hasLoweredContextAccess = false;
     this.hasFireRewrite = false;
-    this.hasInferredEffect = false;
 
     if (
       config.disableMemoizationForDebugging &&
@@ -756,15 +920,10 @@ export class Environment {
       this.#moduleTypes.set(REANIMATED_MODULE_NAME, reanimatedModuleType);
     }
 
-    this.parentFunction = parentFunction;
     this.#contextIdentifiers = contextIdentifiers;
     this.#hoistedIdentifiers = new Set();
   }
 
-  get isInferredMemoEnabled(): boolean {
-    return this.compilerMode !== 'no_inferred_memo';
-  }
-
   get nextIdentifierId(): IdentifierId {
     return makeIdentifierId(this.#nextIdentifer++);
   }
@@ -777,23 +936,6 @@ export class Environment {
     return makeScopeId(this.#nextScope++);
   }
 
-  get scope(): BabelScope {
-    return this.#scope;
-  }
-
-  logErrors(errors: Result<void, CompilerError>): void {
-    if (errors.isOk() || this.logger == null) {
-      return;
-    }
-    for (const error of errors.unwrapErr().details) {
-      this.logger.logEvent(this.filename, {
-        kind: 'CompileError',
-        detail: error,
-        fnLoc: null,
-      });
-    }
-  }
-
   isContextIdentifier(node: t.Identifier): boolean {
     return this.#contextIdentifiers.has(node);
   }
@@ -983,34 +1125,10 @@ export class Environment {
       moduleName.toLowerCase() === 'react-dom'
     );
   }
-  static knownReactModules: ReadonlyArray<string> = ['react', 'react-dom'];
-
-  getFallthroughPropertyType(
-    receiver: Type,
-    _property: Type,
-  ): BuiltInType | PolyType | null {
-    let shapeId = null;
-    if (receiver.kind === 'Object' || receiver.kind === 'Function') {
-      shapeId = receiver.shapeId;
-    }
-
-    if (shapeId !== null) {
-      const shape = this.#shapes.get(shapeId);
-
-      CompilerError.invariant(shape !== undefined, {
-        reason: `[HIR] Forget internal error: cannot resolve shape ${shapeId}`,
-        description: null,
-        loc: null,
-        suggestions: null,
-      });
-      return shape.properties.get('*') ?? null;
-    }
-    return null;
-  }
 
   getPropertyType(
     receiver: Type,
-    property: string | number,
+    property: string,
   ): BuiltInType | PolyType | null {
     let shapeId = null;
     if (receiver.kind === 'Object' || receiver.kind === 'Function') {
@@ -1028,19 +1146,17 @@ export class Environment {
         loc: null,
         suggestions: null,
       });
-      if (typeof property === 'string') {
-        return (
-          shape.properties.get(property) ??
-          shape.properties.get('*') ??
-          (isHookName(property) ? this.#getCustomHookType() : null)
-        );
-      } else {
-        return shape.properties.get('*') ?? null;
+      let value =
+        shape.properties.get(property) ?? shape.properties.get('*') ?? null;
+      if (value === null && isHookName(property)) {
+        value = this.#getCustomHookType();
       }
-    } else if (typeof property === 'string' && isHookName(property)) {
+      return value;
+    } else if (isHookName(property)) {
       return this.#getCustomHookType();
+    } else {
+      return null;
     }
-    return null;
   }
 
   getFunctionSignature(type: FunctionType): FunctionSignature | null {

compiler/packages/babel-plugin-react-compiler/src/HIR/Globals.ts

@@ -9,16 +9,10 @@ import {Effect, ValueKind, ValueReason} from './HIR';
 import {
   BUILTIN_SHAPES,
   BuiltInArrayId,
-  BuiltInAutodepsId,
-  BuiltInFireFunctionId,
   BuiltInFireId,
-  BuiltInMapId,
   BuiltInMixedReadonlyId,
-  BuiltInObjectId,
-  BuiltInSetId,
   BuiltInUseActionStateId,
   BuiltInUseContextHookId,
-  BuiltInUseEffectEventId,
   BuiltInUseEffectHookId,
   BuiltInUseInsertionEffectHookId,
   BuiltInUseLayoutEffectHookId,
@@ -27,10 +21,6 @@ import {
   BuiltInUseRefId,
   BuiltInUseStateId,
   BuiltInUseTransitionId,
-  BuiltInWeakMapId,
-  BuiltInWeakSetId,
-  BuiltinEffectEventId,
-  ReanimatedSharedValueId,
   ShapeRegistry,
   addFunction,
   addHook,
@@ -55,23 +45,29 @@ export const DEFAULT_SHAPES: ShapeRegistry = new Map(BUILTIN_SHAPES);
 
 // Hack until we add ObjectShapes for all globals
 const UNTYPED_GLOBALS: Set<string> = new Set([
+  'String',
   'Object',
   'Function',
+  'Number',
   'RegExp',
   'Date',
   'Error',
+  'Function',
   'TypeError',
   'RangeError',
   'ReferenceError',
   'SyntaxError',
   'URIError',
   'EvalError',
+  'Boolean',
   'DataView',
   'Float32Array',
   'Float64Array',
   'Int8Array',
   'Int16Array',
   'Int32Array',
+  'Map',
+  'Set',
   'WeakMap',
   'Uint8Array',
   'Uint8ClampedArray',
@@ -79,8 +75,16 @@ const UNTYPED_GLOBALS: Set<string> = new Set([
   'Uint32Array',
   'ArrayBuffer',
   'JSON',
+  'parseFloat',
+  'parseInt',
   'console',
+  'isNaN',
   'eval',
+  'isFinite',
+  'encodeURI',
+  'decodeURI',
+  'encodeURIComponent',
+  'decodeURIComponent',
 ]);
 
 const TYPED_GLOBALS: Array<[string, BuiltInType]> = [
@@ -97,23 +101,6 @@ const TYPED_GLOBALS: Array<[string, BuiltInType]> = [
           returnValueKind: ValueKind.Mutable,
         }),
       ],
-      [
-        /**
-         * Object.fromEntries(iterable)
-         * iterable: An iterable, such as an Array or Map, containing a list of
-         *           objects. Each object should have two properties.
-         * Returns a new object whose properties are given by the entries of the
-         * iterable.
-         */
-        'fromEntries',
-        addFunction(DEFAULT_SHAPES, [], {
-          positionalParams: [Effect.ConditionallyMutate],
-          restParam: null,
-          returnType: {kind: 'Object', shapeId: BuiltInObjectId},
-          calleeEffect: Effect.Read,
-          returnValueKind: ValueKind.Mutable,
-        }),
-      ],
     ]),
   ],
   [
@@ -145,7 +132,7 @@ const TYPED_GLOBALS: Array<[string, BuiltInType]> = [
         'from',
         addFunction(DEFAULT_SHAPES, [], {
           positionalParams: [
-            Effect.ConditionallyMutateIterator,
+            Effect.ConditionallyMutate,
             Effect.ConditionallyMutate,
             Effect.ConditionallyMutate,
           ],
@@ -385,150 +372,6 @@ const TYPED_GLOBALS: Array<[string, BuiltInType]> = [
       returnValueKind: ValueKind.Primitive,
     }),
   ],
-  [
-    'parseInt',
-    addFunction(DEFAULT_SHAPES, [], {
-      positionalParams: [],
-      restParam: Effect.Read,
-      returnType: {kind: 'Primitive'},
-      calleeEffect: Effect.Read,
-      returnValueKind: ValueKind.Primitive,
-    }),
-  ],
-  [
-    'parseFloat',
-    addFunction(DEFAULT_SHAPES, [], {
-      positionalParams: [],
-      restParam: Effect.Read,
-      returnType: {kind: 'Primitive'},
-      calleeEffect: Effect.Read,
-      returnValueKind: ValueKind.Primitive,
-    }),
-  ],
-  [
-    'isNaN',
-    addFunction(DEFAULT_SHAPES, [], {
-      positionalParams: [],
-      restParam: Effect.Read,
-      returnType: {kind: 'Primitive'},
-      calleeEffect: Effect.Read,
-      returnValueKind: ValueKind.Primitive,
-    }),
-  ],
-  [
-    'isFinite',
-    addFunction(DEFAULT_SHAPES, [], {
-      positionalParams: [],
-      restParam: Effect.Read,
-      returnType: {kind: 'Primitive'},
-      calleeEffect: Effect.Read,
-      returnValueKind: ValueKind.Primitive,
-    }),
-  ],
-  [
-    'encodeURI',
-    addFunction(DEFAULT_SHAPES, [], {
-      positionalParams: [],
-      restParam: Effect.Read,
-      returnType: {kind: 'Primitive'},
-      calleeEffect: Effect.Read,
-      returnValueKind: ValueKind.Primitive,
-    }),
-  ],
-  [
-    'encodeURIComponent',
-    addFunction(DEFAULT_SHAPES, [], {
-      positionalParams: [],
-      restParam: Effect.Read,
-      returnType: {kind: 'Primitive'},
-      calleeEffect: Effect.Read,
-      returnValueKind: ValueKind.Primitive,
-    }),
-  ],
-  [
-    'decodeURI',
-    addFunction(DEFAULT_SHAPES, [], {
-      positionalParams: [],
-      restParam: Effect.Read,
-      returnType: {kind: 'Primitive'},
-      calleeEffect: Effect.Read,
-      returnValueKind: ValueKind.Primitive,
-    }),
-  ],
-  [
-    'decodeURIComponent',
-    addFunction(DEFAULT_SHAPES, [], {
-      positionalParams: [],
-      restParam: Effect.Read,
-      returnType: {kind: 'Primitive'},
-      calleeEffect: Effect.Read,
-      returnValueKind: ValueKind.Primitive,
-    }),
-  ],
-  [
-    'Map',
-    addFunction(
-      DEFAULT_SHAPES,
-      [],
-      {
-        positionalParams: [Effect.ConditionallyMutateIterator],
-        restParam: null,
-        returnType: {kind: 'Object', shapeId: BuiltInMapId},
-        calleeEffect: Effect.Read,
-        returnValueKind: ValueKind.Mutable,
-      },
-      null,
-      true,
-    ),
-  ],
-  [
-    'Set',
-    addFunction(
-      DEFAULT_SHAPES,
-      [],
-      {
-        positionalParams: [Effect.ConditionallyMutateIterator],
-        restParam: null,
-        returnType: {kind: 'Object', shapeId: BuiltInSetId},
-        calleeEffect: Effect.Read,
-        returnValueKind: ValueKind.Mutable,
-      },
-      null,
-      true,
-    ),
-  ],
-  [
-    'WeakMap',
-    addFunction(
-      DEFAULT_SHAPES,
-      [],
-      {
-        positionalParams: [Effect.ConditionallyMutateIterator],
-        restParam: null,
-        returnType: {kind: 'Object', shapeId: BuiltInWeakMapId},
-        calleeEffect: Effect.Read,
-        returnValueKind: ValueKind.Mutable,
-      },
-      null,
-      true,
-    ),
-  ],
-  [
-    'WeakSet',
-    addFunction(
-      DEFAULT_SHAPES,
-      [],
-      {
-        positionalParams: [Effect.ConditionallyMutateIterator],
-        restParam: null,
-        returnType: {kind: 'Object', shapeId: BuiltInWeakSetId},
-        calleeEffect: Effect.Read,
-        returnValueKind: ValueKind.Mutable,
-      },
-      null,
-      true,
-    ),
-  ],
   // TODO: rest of Global objects
 ];
 
@@ -645,41 +488,6 @@ const REACT_APIS: Array<[string, BuiltInType]> = [
         calleeEffect: Effect.Read,
         hookKind: 'useEffect',
         returnValueKind: ValueKind.Frozen,
-        aliasing: {
-          receiver: '@receiver',
-          params: [],
-          rest: '@rest',
-          returns: '@returns',
-          temporaries: ['@effect'],
-          effects: [
-            // Freezes the function and deps
-            {
-              kind: 'Freeze',
-              value: '@rest',
-              reason: ValueReason.Effect,
-            },
-            // Internally creates an effect object that captures the function and deps
-            {
-              kind: 'Create',
-              into: '@effect',
-              value: ValueKind.Frozen,
-              reason: ValueReason.KnownReturnSignature,
-            },
-            // The effect stores the function and dependencies
-            {
-              kind: 'Capture',
-              from: '@rest',
-              into: '@effect',
-            },
-            // Returns undefined
-            {
-              kind: 'Create',
-              into: '@returns',
-              value: ValueKind.Primitive,
-              reason: ValueReason.KnownReturnSignature,
-            },
-          ],
-        },
       },
       BuiltInUseEffectHookId,
     ),
@@ -748,40 +556,13 @@ const REACT_APIS: Array<[string, BuiltInType]> = [
       {
         positionalParams: [],
         restParam: null,
-        returnType: {
-          kind: 'Function',
-          return: {kind: 'Poly'},
-          shapeId: BuiltInFireFunctionId,
-          isConstructor: false,
-        },
+        returnType: {kind: 'Primitive'},
         calleeEffect: Effect.Read,
         returnValueKind: ValueKind.Frozen,
       },
       BuiltInFireId,
     ),
   ],
-  [
-    'useEffectEvent',
-    addHook(
-      DEFAULT_SHAPES,
-      {
-        positionalParams: [],
-        restParam: Effect.Freeze,
-        returnType: {
-          kind: 'Function',
-          return: {kind: 'Poly'},
-          shapeId: BuiltinEffectEventId,
-          isConstructor: false,
-        },
-        calleeEffect: Effect.Read,
-        hookKind: 'useEffectEvent',
-        // Frozen because it should not mutate any locally-bound values
-        returnValueKind: ValueKind.Frozen,
-      },
-      BuiltInUseEffectEventId,
-    ),
-  ],
-  ['AUTODEPS', addObject(DEFAULT_SHAPES, BuiltInAutodepsId, [])],
 ];
 
 TYPED_GLOBALS.push(
@@ -907,7 +688,6 @@ export function installTypeConfig(
         noAlias: typeConfig.noAlias === true,
         mutableOnlyIfOperandsAreMutable:
           typeConfig.mutableOnlyIfOperandsAreMutable === true,
-        aliasing: typeConfig.aliasing,
       });
     }
     case 'hook': {
@@ -925,7 +705,6 @@ export function installTypeConfig(
         ),
         returnValueKind: typeConfig.returnValueKind ?? ValueKind.Frozen,
         noAlias: typeConfig.noAlias === true,
-        aliasing: typeConfig.aliasing,
       });
     }
     case 'object': {
@@ -1005,7 +784,7 @@ export function getReanimatedModuleType(registry: ShapeRegistry): ObjectType {
       addHook(registry, {
         positionalParams: [],
         restParam: Effect.Freeze,
-        returnType: {kind: 'Object', shapeId: ReanimatedSharedValueId},
+        returnType: {kind: 'Poly'},
         returnValueKind: ValueKind.Mutable,
         noAlias: true,
         calleeEffect: Effect.Read,

compiler/packages/babel-plugin-react-compiler/src/HIR/HIR.ts

@@ -10,10 +10,9 @@ import * as t from '@babel/types';
 import {CompilerError, CompilerErrorDetailOptions} from '../CompilerError';
 import {assertExhaustive} from '../Utils/utils';
 import {Environment, ReactFunctionType} from './Environment';
-import type {HookKind} from './ObjectShape';
+import {HookKind} from './ObjectShape';
 import {Type, makeType} from './Types';
 import {z} from 'zod';
-import type {AliasingEffect} from '../Inference/AliasingEffects';
 
 /*
  * *******************************************************************************************
@@ -101,7 +100,6 @@ export type ReactiveInstruction = {
   id: InstructionId;
   lvalue: Place | null;
   value: ReactiveValue;
-  effects?: Array<AliasingEffect> | null; // TODO make non-optional
   loc: SourceLocation;
 };
 
@@ -279,14 +277,13 @@ export type HIRFunction = {
   env: Environment;
   params: Array<Place | SpreadPattern>;
   returnTypeAnnotation: t.FlowType | t.TSType | null;
-  returns: Place;
+  returnType: Type;
   context: Array<Place>;
   effects: Array<FunctionEffect> | null;
   body: HIR;
   generator: boolean;
   async: boolean;
   directives: Array<string>;
-  aliasingEffects?: Array<AliasingEffect> | null;
 };
 
 export type FunctionEffect =
@@ -446,25 +443,12 @@ export type ThrowTerminal = {
 };
 export type Case = {test: Place | null; block: BlockId};
 
-export type ReturnVariant = 'Void' | 'Implicit' | 'Explicit';
 export type ReturnTerminal = {
   kind: 'return';
-  /**
-   * Void:
-   *   () => { ... }
-   *   function() { ... }
-   * Implicit (ArrowFunctionExpression only):
-   *   () => foo
-   * Explicit:
-   *   () => { return ... }
-   *   function () { return ... }
-   */
-  returnVariant: ReturnVariant;
   loc: SourceLocation;
   value: Place;
   id: InstructionId;
   fallthrough?: never;
-  effects: Array<AliasingEffect> | null;
 };
 
 export type GotoTerminal = {
@@ -625,7 +609,6 @@ export type MaybeThrowTerminal = {
   id: InstructionId;
   loc: SourceLocation;
   fallthrough?: never;
-  effects: Array<AliasingEffect> | null;
 };
 
 export type ReactiveScopeTerminal = {
@@ -662,14 +645,12 @@ export type Instruction = {
   lvalue: Place;
   value: InstructionValue;
   loc: SourceLocation;
-  effects: Array<AliasingEffect> | null;
 };
 
 export type TInstruction<T extends InstructionValue> = {
   id: InstructionId;
   lvalue: Place;
   value: T;
-  effects: Array<AliasingEffect> | null;
   loc: SourceLocation;
 };
 
@@ -722,10 +703,6 @@ export type ObjectPropertyKey =
   | {
       kind: 'computed';
       name: Place;
-    }
-  | {
-      kind: 'number';
-      name: number;
     };
 
 export type ObjectProperty = {
@@ -765,27 +742,6 @@ export enum InstructionKind {
   Function = 'Function',
 }
 
-export function convertHoistedLValueKind(
-  kind: InstructionKind,
-): InstructionKind | null {
-  switch (kind) {
-    case InstructionKind.HoistedLet:
-      return InstructionKind.Let;
-    case InstructionKind.HoistedConst:
-      return InstructionKind.Const;
-    case InstructionKind.HoistedFunction:
-      return InstructionKind.Function;
-    case InstructionKind.Let:
-    case InstructionKind.Const:
-    case InstructionKind.Function:
-    case InstructionKind.Reassign:
-    case InstructionKind.Catch:
-      return null;
-    default:
-      assertExhaustive(kind, 'Unexpected lvalue kind');
-  }
-}
-
 function _staticInvariantInstructionValueHasLocation(
   value: InstructionValue,
 ): SourceLocation {
@@ -869,13 +825,6 @@ export type CallExpression = {
   typeArguments?: Array<t.FlowType>;
 };
 
-export type NewExpression = {
-  kind: 'NewExpression';
-  callee: Place;
-  args: Array<Place | SpreadPattern>;
-  loc: SourceLocation;
-};
-
 export type LoadLocal = {
   kind: 'LoadLocal';
   place: Place;
@@ -920,20 +869,8 @@ export type InstructionValue =
   | StoreLocal
   | {
       kind: 'StoreContext';
-      /**
-       * StoreContext kinds:
-       * Reassign: context variable reassignment in source
-       * Const:    const declaration + assignment in source
-       *           ('const' context vars are ones whose declarations are hoisted)
-       * Let:      let declaration + assignment in source
-       * Function: function declaration in source (similar to `const`)
-       */
       lvalue: {
-        kind:
-          | InstructionKind.Reassign
-          | InstructionKind.Const
-          | InstructionKind.Let
-          | InstructionKind.Function;
+        kind: InstructionKind.Reassign;
         place: Place;
       };
       value: Place;
@@ -953,7 +890,12 @@ export type InstructionValue =
       right: Place;
       loc: SourceLocation;
     }
-  | NewExpression
+  | {
+      kind: 'NewExpression';
+      callee: Place;
+      args: Array<Place | SpreadPattern>;
+      loc: SourceLocation;
+    }
   | CallExpression
   | MethodCall
   | {
@@ -962,21 +904,13 @@ export type InstructionValue =
       value: Place;
       loc: SourceLocation;
     }
-  | ({
+  | {
       kind: 'TypeCastExpression';
       value: Place;
+      typeAnnotation: t.FlowType | t.TSType;
       type: Type;
       loc: SourceLocation;
-    } & (
-      | {
-          typeAnnotation: t.FlowType;
-          typeAnnotationKind: 'cast';
-        }
-      | {
-          typeAnnotation: t.TSType;
-          typeAnnotationKind: 'as' | 'satisfies';
-        }
-    ))
+    }
   | JsxExpression
   | {
       kind: 'ObjectExpression';
@@ -1227,21 +1161,18 @@ export type VariableBinding =
   // bindings declard outside the current component/hook
   | NonLocalBinding;
 
-// `import {bar as baz} from 'foo'`: name=baz, module=foo, imported=bar
-export type NonLocalImportSpecifier = {
-  kind: 'ImportSpecifier';
-  name: string;
-  module: string;
-  imported: string;
-};
-
 export type NonLocalBinding =
   // `import Foo from 'foo'`: name=Foo, module=foo
   | {kind: 'ImportDefault'; name: string; module: string}
   // `import * as Foo from 'foo'`: name=Foo, module=foo
   | {kind: 'ImportNamespace'; name: string; module: string}
-  // `import {bar as baz} from 'foo'`
-  | NonLocalImportSpecifier
+  // `import {bar as baz} from 'foo'`: name=baz, module=foo, imported=bar
+  | {
+      kind: 'ImportSpecifier';
+      name: string;
+      module: string;
+      imported: string;
+    }
   // let, const, function, etc declared in the module but outside the current component/hook
   | {kind: 'ModuleLocal'; name: string}
   // an unresolved binding
@@ -1399,21 +1330,6 @@ export enum ValueReason {
    */
   JsxCaptured = 'jsx-captured',
 
-  /**
-   * Argument to a hook
-   */
-  HookCaptured = 'hook-captured',
-
-  /**
-   * Return value of a hook
-   */
-  HookReturn = 'hook-return',
-
-  /**
-   * Passed to an effect
-   */
-  Effect = 'effect',
-
   /**
    * Return value of a function with known frozen return value, e.g. `useState`.
    */
@@ -1464,20 +1380,6 @@ export const ValueKindSchema = z.enum([
   ValueKind.Context,
 ]);
 
-export const ValueReasonSchema = z.enum([
-  ValueReason.Context,
-  ValueReason.Effect,
-  ValueReason.Global,
-  ValueReason.HookCaptured,
-  ValueReason.HookReturn,
-  ValueReason.JsxCaptured,
-  ValueReason.KnownReturnSignature,
-  ValueReason.Other,
-  ValueReason.ReactiveFunctionArgument,
-  ValueReason.ReducerState,
-  ValueReason.State,
-]);
-
 // The effect with which a value is modified.
 export enum Effect {
   // Default value: not allowed after lifetime inference
@@ -1488,7 +1390,6 @@ export enum Effect {
   Read = 'read',
   // This reference reads and stores the value
   Capture = 'capture',
-  ConditionallyMutateIterator = 'mutate-iterator?',
   /*
    * This reference *may* write to (mutate) the value. This covers two similar cases:
    * - The compiler is being conservative and assuming that a value *may* be mutated
@@ -1507,11 +1408,11 @@ export enum Effect {
   // This reference may alias to (mutate) the value
   Store = 'store',
 }
+
 export const EffectSchema = z.enum([
   Effect.Read,
   Effect.Mutate,
   Effect.ConditionallyMutate,
-  Effect.ConditionallyMutateIterator,
   Effect.Capture,
   Effect.Store,
   Effect.Freeze,
@@ -1525,7 +1426,6 @@ export function isMutableEffect(
     case Effect.Capture:
     case Effect.Store:
     case Effect.ConditionallyMutate:
-    case Effect.ConditionallyMutateIterator:
     case Effect.Mutate: {
       return true;
     }
@@ -1616,18 +1516,6 @@ export type DependencyPathEntry = {
 export type DependencyPath = Array<DependencyPathEntry>;
 export type ReactiveScopeDependency = {
   identifier: Identifier;
-  /**
-   * Reflects whether the base identifier is reactive. Note that some reactive
-   * objects may have non-reactive properties, but we do not currently track
-   * this.
-   *
-   * ```js
-   * // Technically, result[0] is reactive and result[1] is not.
-   * // Currently, both dependencies would be marked as reactive.
-   * const result = useState();
-   * ```
-   */
-  reactive: boolean;
   path: DependencyPath;
 };
 
@@ -1757,14 +1645,6 @@ export function isArrayType(id: Identifier): boolean {
   return id.type.kind === 'Object' && id.type.shapeId === 'BuiltInArray';
 }
 
-export function isMapType(id: Identifier): boolean {
-  return id.type.kind === 'Object' && id.type.shapeId === 'BuiltInMap';
-}
-
-export function isSetType(id: Identifier): boolean {
-  return id.type.kind === 'Object' && id.type.shapeId === 'BuiltInSet';
-}
-
 export function isPropsType(id: Identifier): boolean {
   return id.type.kind === 'Object' && id.type.shapeId === 'BuiltInProps';
 }
@@ -1781,26 +1661,10 @@ export function isUseStateType(id: Identifier): boolean {
   return id.type.kind === 'Object' && id.type.shapeId === 'BuiltInUseState';
 }
 
-export function isJsxType(type: Type): boolean {
-  return type.kind === 'Object' && type.shapeId === 'BuiltInJsx';
-}
-
 export function isRefOrRefValue(id: Identifier): boolean {
   return isUseRefType(id) || isRefValueType(id);
 }
 
-/*
- * Returns true if the type is a Ref or a custom user type that acts like a ref when it
- * shouldn't. For now the only other case of this is Reanimated's shared values.
- */
-export function isRefOrRefLikeMutableType(type: Type): boolean {
-  return (
-    type.kind === 'Object' &&
-    (type.shapeId === 'BuiltInUseRefId' ||
-      type.shapeId == 'ReanimatedSharedValueId')
-  );
-}
-
 export function isSetStateType(id: Identifier): boolean {
   return id.type.kind === 'Function' && id.type.shapeId === 'BuiltInSetState';
 }
@@ -1831,19 +1695,6 @@ export function isDispatcherType(id: Identifier): boolean {
   return id.type.kind === 'Function' && id.type.shapeId === 'BuiltInDispatch';
 }
 
-export function isFireFunctionType(id: Identifier): boolean {
-  return (
-    id.type.kind === 'Function' && id.type.shapeId === 'BuiltInFireFunction'
-  );
-}
-
-export function isEffectEventFunctionType(id: Identifier): boolean {
-  return (
-    id.type.kind === 'Function' &&
-    id.type.shapeId === 'BuiltInEffectEventFunction'
-  );
-}
-
 export function isStableType(id: Identifier): boolean {
   return (
     isSetStateType(id) ||
@@ -1854,40 +1705,6 @@ export function isStableType(id: Identifier): boolean {
   );
 }
 
-export function isStableTypeContainer(id: Identifier): boolean {
-  const type_ = id.type;
-  if (type_.kind !== 'Object') {
-    return false;
-  }
-  return (
-    isUseStateType(id) || // setState
-    type_.shapeId === 'BuiltInUseActionState' || // setActionState
-    isUseReducerType(id) || // dispatcher
-    type_.shapeId === 'BuiltInUseTransition' // startTransition
-  );
-}
-
-export function evaluatesToStableTypeOrContainer(
-  env: Environment,
-  {value}: Instruction,
-): boolean {
-  if (value.kind === 'CallExpression' || value.kind === 'MethodCall') {
-    const callee =
-      value.kind === 'CallExpression' ? value.callee : value.property;
-
-    const calleeHookKind = getHookKind(env, callee.identifier);
-    switch (calleeHookKind) {
-      case 'useState':
-      case 'useReducer':
-      case 'useActionState':
-      case 'useRef':
-      case 'useTransition':
-        return true;
-    }
-  }
-  return false;
-}
-
 export function isUseEffectHookType(id: Identifier): boolean {
   return (
     id.type.kind === 'Function' && id.type.shapeId === 'BuiltInUseEffectHook'

compiler/packages/babel-plugin-react-compiler/src/HIR/HIRBuilder.ts

@@ -7,7 +7,7 @@
 
 import {Binding, NodePath} from '@babel/traverse';
 import * as t from '@babel/types';
-import {CompilerError, ErrorSeverity} from '../CompilerError';
+import {CompilerError} from '../CompilerError';
 import {Environment} from './Environment';
 import {
   BasicBlock,
@@ -106,10 +106,11 @@ export default class HIRBuilder {
   #current: WipBlock;
   #entry: BlockId;
   #scopes: Array<Scope> = [];
-  #context: Map<t.Identifier, SourceLocation>;
+  #context: Array<t.Identifier>;
   #bindings: Bindings;
   #env: Environment;
   #exceptionHandlerStack: Array<BlockId> = [];
+  parentFunction: NodePath<t.Function>;
   errors: CompilerError = new CompilerError();
   /**
    * Traversal context: counts the number of `fbt` tag parents
@@ -121,7 +122,7 @@ export default class HIRBuilder {
     return this.#env.nextIdentifierId;
   }
 
-  get context(): Map<t.Identifier, SourceLocation> {
+  get context(): Array<t.Identifier> {
     return this.#context;
   }
 
@@ -135,17 +136,16 @@ export default class HIRBuilder {
 
   constructor(
     env: Environment,
-    options?: {
-      bindings?: Bindings | null;
-      context?: Map<t.Identifier, SourceLocation>;
-      entryBlockKind?: BlockKind;
-    },
+    parentFunction: NodePath<t.Function>, // the outermost function being compiled
+    bindings: Bindings | null = null,
+    context: Array<t.Identifier> | null = null,
   ) {
     this.#env = env;
-    this.#bindings = options?.bindings ?? new Map();
-    this.#context = options?.context ?? new Map();
+    this.#bindings = bindings ?? new Map();
+    this.parentFunction = parentFunction;
+    this.#context = context ?? [];
     this.#entry = makeBlockId(env.nextBlockId);
-    this.#current = newBlock(this.#entry, options?.entryBlockKind ?? 'block');
+    this.#current = newBlock(this.#entry, 'block');
   }
 
   currentBlockKind(): BlockKind {
@@ -165,7 +165,6 @@ export default class HIRBuilder {
           handler: exceptionHandler,
           id: makeInstructionId(0),
           loc: instruction.loc,
-          effects: null,
         },
         continuationBlock,
       );
@@ -240,7 +239,7 @@ export default class HIRBuilder {
 
     // Check if the binding is from module scope
     const outerBinding =
-      this.#env.parentFunction.scope.parent.getBinding(originalName);
+      this.parentFunction.scope.parent.getBinding(originalName);
     if (babelBinding === outerBinding) {
       const path = babelBinding.path;
       if (path.isImportDefaultSpecifier()) {
@@ -294,7 +293,7 @@ export default class HIRBuilder {
     const binding = this.#resolveBabelBinding(path);
     if (binding) {
       // Check if the binding is from module scope, if so return null
-      const outerBinding = this.#env.parentFunction.scope.parent.getBinding(
+      const outerBinding = this.parentFunction.scope.parent.getBinding(
         path.node.name,
       );
       if (binding === outerBinding) {
@@ -308,18 +307,9 @@ export default class HIRBuilder {
 
   resolveBinding(node: t.Identifier): Identifier {
     if (node.name === 'fbt') {
-      CompilerError.throwDiagnostic({
-        severity: ErrorSeverity.Todo,
-        category: 'Support local variables named `fbt`',
-        description:
-          'Local variables named `fbt` may conflict with the fbt plugin and are not yet supported',
-        details: [
-          {
-            kind: 'error',
-            message: 'Rename to avoid conflict with fbt plugin',
-            loc: node.loc ?? GeneratedSource,
-          },
-        ],
+      CompilerError.throwTodo({
+        reason: 'Support local variables named "fbt"',
+        loc: node.loc ?? null,
       });
     }
     const originalName = node.name;
@@ -341,7 +331,6 @@ export default class HIRBuilder {
           type: makeType(),
           loc: node.loc ?? GeneratedSource,
         };
-        this.#env.programContext.addNewReference(name);
         this.#bindings.set(name, {node, identifier});
         return identifier;
       } else if (mapping.node === node) {
@@ -386,7 +375,7 @@ export default class HIRBuilder {
   }
 
   // Terminate the current block w the given terminal, and start a new block
-  terminate(terminal: Terminal, nextBlockKind: BlockKind | null): BlockId {
+  terminate(terminal: Terminal, nextBlockKind: BlockKind | null): void {
     const {id: blockId, kind, instructions} = this.#current;
     this.#completed.set(blockId, {
       kind,
@@ -400,7 +389,6 @@ export default class HIRBuilder {
       const nextId = this.#env.nextBlockId;
       this.#current = newBlock(nextId, nextBlockKind);
     }
-    return blockId;
   }
 
   /*
@@ -757,11 +745,6 @@ function getReversePostorderedBlocks(func: HIR): HIR['blocks'] {
      * (eg bb2 then bb1), we ensure that they get reversed back to the correct order.
      */
     const block = func.blocks.get(blockId)!;
-    CompilerError.invariant(block != null, {
-      reason: '[HIRBuilder] Unexpected null block',
-      description: `expected block ${blockId} to exist`,
-      loc: GeneratedSource,
-    });
     const successors = [...eachTerminalSuccessor(block.terminal)].reverse();
     const fallthrough = terminalFallthrough(block.terminal);
 

compiler/packages/babel-plugin-react-compiler/src/HIR/MergeConsecutiveBlocks.ts

@@ -12,7 +12,6 @@ import {
   GeneratedSource,
   HIRFunction,
   Instruction,
-  Place,
 } from './HIR';
 import {markPredecessors} from './HIRBuilder';
 import {terminalFallthrough, terminalHasFallthrough} from './visitors';
@@ -81,22 +80,20 @@ export function mergeConsecutiveBlocks(fn: HIRFunction): void {
         suggestions: null,
       });
       const operand = Array.from(phi.operands.values())[0]!;
-      const lvalue: Place = {
-        kind: 'Identifier',
-        identifier: phi.place.identifier,
-        effect: Effect.ConditionallyMutate,
-        reactive: false,
-        loc: GeneratedSource,
-      };
       const instr: Instruction = {
         id: predecessor.terminal.id,
-        lvalue: {...lvalue},
+        lvalue: {
+          kind: 'Identifier',
+          identifier: phi.place.identifier,
+          effect: Effect.ConditionallyMutate,
+          reactive: false,
+          loc: GeneratedSource,
+        },
         value: {
           kind: 'LoadLocal',
           place: {...operand},
           loc: GeneratedSource,
         },
-        effects: [{kind: 'Alias', from: {...operand}, into: {...lvalue}}],
         loc: GeneratedSource,
       };
       predecessor.instructions.push(instr);
@@ -107,17 +104,6 @@ export function mergeConsecutiveBlocks(fn: HIRFunction): void {
     merged.merge(block.id, predecessorId);
     fn.body.blocks.delete(block.id);
   }
-  for (const [, block] of fn.body.blocks) {
-    for (const phi of block.phis) {
-      for (const [predecessorId, operand] of phi.operands) {
-        const mapped = merged.get(predecessorId);
-        if (mapped !== predecessorId) {
-          phi.operands.delete(predecessorId);
-          phi.operands.set(mapped, operand);
-        }
-      }
-    }
-  }
   markPredecessors(fn.body);
   for (const [, {terminal}] of fn.body.blocks) {
     if (terminalHasFallthrough(terminal)) {

compiler/packages/babel-plugin-react-compiler/src/HIR/MergeOverlappingReactiveScopesHIR.ts

@@ -1,10 +1,3 @@
-/**
- * Copyright (c) Meta Platforms, Inc. and affiliates.
- *
- * This source code is licensed under the MIT license found in the
- * LICENSE file in the root directory of this source tree.
- */
-
 import {
   HIRFunction,
   InstructionId,

compiler/packages/babel-plugin-react-compiler/src/HIR/ObjectShape.ts

@@ -6,30 +6,14 @@
  */
 
 import {CompilerError} from '../CompilerError';
-import {AliasingEffect, AliasingSignature} from '../Inference/AliasingEffects';
-import {assertExhaustive} from '../Utils/utils';
-import {
-  Effect,
-  GeneratedSource,
-  Hole,
-  makeDeclarationId,
-  makeIdentifierId,
-  makeInstructionId,
-  Place,
-  SourceLocation,
-  SpreadPattern,
-  ValueKind,
-  ValueReason,
-} from './HIR';
+import {Effect, ValueKind, ValueReason} from './HIR';
 import {
   BuiltInType,
   FunctionType,
-  makeType,
   ObjectType,
   PolyType,
   PrimitiveType,
 } from './Types';
-import {AliasingEffectConfig, AliasingSignatureConfig} from './TypeSchema';
 
 /*
  * This file exports types and defaults for JavaScript object shapes. These are
@@ -58,27 +42,18 @@ function createAnonId(): string {
 export function addFunction(
   registry: ShapeRegistry,
   properties: Iterable<[string, BuiltInType | PolyType]>,
-  fn: Omit<FunctionSignature, 'hookKind' | 'aliasing'> & {
-    aliasing?: AliasingSignatureConfig | null | undefined;
-  },
+  fn: Omit<FunctionSignature, 'hookKind'>,
   id: string | null = null,
-  isConstructor: boolean = false,
 ): FunctionType {
   const shapeId = id ?? createAnonId();
-  const aliasing =
-    fn.aliasing != null
-      ? parseAliasingSignatureConfig(fn.aliasing, '<builtin>', GeneratedSource)
-      : null;
   addShape(registry, shapeId, properties, {
     ...fn,
-    aliasing,
     hookKind: null,
   });
   return {
     kind: 'Function',
     return: fn.returnType,
     shapeId,
-    isConstructor,
   };
 }
 
@@ -89,146 +64,15 @@ export function addFunction(
  */
 export function addHook(
   registry: ShapeRegistry,
-  fn: Omit<FunctionSignature, 'aliasing'> & {
-    hookKind: HookKind;
-    aliasing?: AliasingSignatureConfig | null | undefined;
-  },
+  fn: FunctionSignature & {hookKind: HookKind},
   id: string | null = null,
 ): FunctionType {
   const shapeId = id ?? createAnonId();
-  const aliasing =
-    fn.aliasing != null
-      ? parseAliasingSignatureConfig(fn.aliasing, '<builtin>', GeneratedSource)
-      : null;
-  addShape(registry, shapeId, [], {...fn, aliasing});
+  addShape(registry, shapeId, [], fn);
   return {
     kind: 'Function',
     return: fn.returnType,
     shapeId,
-    isConstructor: false,
-  };
-}
-
-function parseAliasingSignatureConfig(
-  typeConfig: AliasingSignatureConfig,
-  moduleName: string,
-  loc: SourceLocation,
-): AliasingSignature {
-  const lifetimes = new Map<string, Place>();
-  function define(temp: string): Place {
-    CompilerError.invariant(!lifetimes.has(temp), {
-      reason: `Invalid type configuration for module`,
-      description: `Expected aliasing signature to have unique names for receiver, params, rest, returns, and temporaries in module '${moduleName}'`,
-      loc,
-    });
-    const place = signatureArgument(lifetimes.size);
-    lifetimes.set(temp, place);
-    return place;
-  }
-  function lookup(temp: string): Place {
-    const place = lifetimes.get(temp);
-    CompilerError.invariant(place != null, {
-      reason: `Invalid type configuration for module`,
-      description: `Expected aliasing signature effects to reference known names from receiver/params/rest/returns/temporaries, but '${temp}' is not a known name in '${moduleName}'`,
-      loc,
-    });
-    return place;
-  }
-  const receiver = define(typeConfig.receiver);
-  const params = typeConfig.params.map(define);
-  const rest = typeConfig.rest != null ? define(typeConfig.rest) : null;
-  const returns = define(typeConfig.returns);
-  const temporaries = typeConfig.temporaries.map(define);
-  const effects = typeConfig.effects.map(
-    (effect: AliasingEffectConfig): AliasingEffect => {
-      switch (effect.kind) {
-        case 'CreateFrom':
-        case 'Capture':
-        case 'Alias':
-        case 'Assign': {
-          const from = lookup(effect.from);
-          const into = lookup(effect.into);
-          return {
-            kind: effect.kind,
-            from,
-            into,
-          };
-        }
-        case 'Mutate':
-        case 'MutateTransitiveConditionally': {
-          const value = lookup(effect.value);
-          return {kind: effect.kind, value};
-        }
-        case 'Create': {
-          const into = lookup(effect.into);
-          return {
-            kind: 'Create',
-            into,
-            reason: effect.reason,
-            value: effect.value,
-          };
-        }
-        case 'Freeze': {
-          const value = lookup(effect.value);
-          return {
-            kind: 'Freeze',
-            value,
-            reason: effect.reason,
-          };
-        }
-        case 'Impure': {
-          const place = lookup(effect.place);
-          return {
-            kind: 'Impure',
-            place,
-            error: CompilerError.throwTodo({
-              reason: 'Support impure effect declarations',
-              loc: GeneratedSource,
-            }),
-          };
-        }
-        case 'Apply': {
-          const receiver = lookup(effect.receiver);
-          const fn = lookup(effect.function);
-          const args: Array<Place | SpreadPattern | Hole> = effect.args.map(
-            arg => {
-              if (typeof arg === 'string') {
-                return lookup(arg);
-              } else if (arg.kind === 'Spread') {
-                return {kind: 'Spread', place: lookup(arg.place)};
-              } else {
-                return arg;
-              }
-            },
-          );
-          const into = lookup(effect.into);
-          return {
-            kind: 'Apply',
-            receiver,
-            function: fn,
-            mutatesFunction: effect.mutatesFunction,
-            args,
-            into,
-            loc,
-            signature: null,
-          };
-        }
-        default: {
-          assertExhaustive(
-            effect,
-            `Unexpected effect kind '${(effect as any).kind}'`,
-          );
-        }
-      }
-    },
-  );
-  return {
-    receiver: receiver.identifier.id,
-    params: params.map(p => p.identifier.id),
-    rest: rest != null ? rest.identifier.id : null,
-    returns: returns.identifier.id,
-    temporaries,
-    effects,
   };
 }
 
@@ -284,7 +128,6 @@ export type HookKind =
   | 'useCallback'
   | 'useTransition'
   | 'useImperativeHandle'
-  | 'useEffectEvent'
   | 'Custom';
 
 /*
@@ -333,8 +176,6 @@ export type FunctionSignature = {
   impure?: boolean;
 
   canonicalName?: string;
-
-  aliasing?: AliasingSignature | null | undefined;
 };
 
 /*
@@ -357,10 +198,6 @@ export type ObjectShape = {
 export type ShapeRegistry = Map<string, ObjectShape>;
 export const BuiltInPropsId = 'BuiltInProps';
 export const BuiltInArrayId = 'BuiltInArray';
-export const BuiltInSetId = 'BuiltInSet';
-export const BuiltInMapId = 'BuiltInMap';
-export const BuiltInWeakSetId = 'BuiltInWeakSet';
-export const BuiltInWeakMapId = 'BuiltInWeakMap';
 export const BuiltInFunctionId = 'BuiltInFunction';
 export const BuiltInJsxId = 'BuiltInJsx';
 export const BuiltInObjectId = 'BuiltInObject';
@@ -381,13 +218,6 @@ export const BuiltInUseContextHookId = 'BuiltInUseContextHook';
 export const BuiltInUseTransitionId = 'BuiltInUseTransition';
 export const BuiltInStartTransitionId = 'BuiltInStartTransition';
 export const BuiltInFireId = 'BuiltInFire';
-export const BuiltInFireFunctionId = 'BuiltInFireFunction';
-export const BuiltInUseEffectEventId = 'BuiltInUseEffectEvent';
-export const BuiltinEffectEventId = 'BuiltInEffectEventFunction';
-export const BuiltInAutodepsId = 'BuiltInAutoDepsId';
-
-// See getReanimatedModuleType() in Globals.ts — this is part of supporting Reanimated's ref-like types
-export const ReanimatedSharedValueId = 'ReanimatedSharedValueId';
 
 // ShapeRegistry with default definitions for built-ins.
 export const BUILTIN_SHAPES: ShapeRegistry = new Map();
@@ -461,30 +291,6 @@ addObject(BUILTIN_SHAPES, BuiltInArrayId, [
       returnType: PRIMITIVE_TYPE,
       calleeEffect: Effect.Store,
       returnValueKind: ValueKind.Primitive,
-      aliasing: {
-        receiver: '@receiver',
-        params: [],
-        rest: '@rest',
-        returns: '@returns',
-        temporaries: [],
-        effects: [
-          // Push directly mutates the array itself
-          {kind: 'Mutate', value: '@receiver'},
-          // The arguments are captured into the array
-          {
-            kind: 'Capture',
-            from: '@rest',
-            into: '@receiver',
-          },
-          // Returns the new length, a primitive
-          {
-            kind: 'Create',
-            into: '@returns',
-            value: ValueKind.Primitive,
-            reason: ValueReason.KnownReturnSignature,
-          },
-        ],
-      },
     }),
   ],
   [
@@ -515,60 +321,6 @@ addObject(BUILTIN_SHAPES, BuiltInArrayId, [
       returnValueKind: ValueKind.Mutable,
       noAlias: true,
       mutableOnlyIfOperandsAreMutable: true,
-      aliasing: {
-        receiver: '@receiver',
-        params: ['@callback'],
-        rest: null,
-        returns: '@returns',
-        temporaries: [
-          // Temporary representing captured items of the receiver
-          '@item',
-          // Temporary representing the result of the callback
-          '@callbackReturn',
-          /*
-           * Undefined `this` arg to the callback. Note the signature does not
-           * support passing an explicit thisArg second param
-           */
-          '@thisArg',
-        ],
-        effects: [
-          // Map creates a new mutable array
-          {
-            kind: 'Create',
-            into: '@returns',
-            value: ValueKind.Mutable,
-            reason: ValueReason.KnownReturnSignature,
-          },
-          // The first arg to the callback is an item extracted from the receiver array
-          {
-            kind: 'CreateFrom',
-            from: '@receiver',
-            into: '@item',
-          },
-          // The undefined this for the callback
-          {
-            kind: 'Create',
-            into: '@thisArg',
-            value: ValueKind.Primitive,
-            reason: ValueReason.KnownReturnSignature,
-          },
-          // calls the callback, returning the result into a temporary
-          {
-            kind: 'Apply',
-            receiver: '@thisArg',
-            args: ['@item', {kind: 'Hole'}, '@receiver'],
-            function: '@callback',
-            into: '@callbackReturn',
-            mutatesFunction: false,
-          },
-          // captures the result of the callback into the return array
-          {
-            kind: 'Capture',
-            from: '@callbackReturn',
-            into: '@returns',
-          },
-        ],
-      },
     }),
   ],
   [
@@ -699,434 +451,6 @@ addObject(BUILTIN_SHAPES, BuiltInObjectId, [
    */
 ]);
 
-/* Built-in Set shape */
-addObject(BUILTIN_SHAPES, BuiltInSetId, [
-  [
-    /**
-     * add(value)
-     * Parameters
-     *   value: the value of the element to add to the Set object.
-     * Returns the Set object with added value.
-     */
-    'add',
-    addFunction(BUILTIN_SHAPES, [], {
-      positionalParams: [Effect.Capture],
-      restParam: null,
-      returnType: {kind: 'Object', shapeId: BuiltInSetId},
-      calleeEffect: Effect.Store,
-      // returnValueKind is technically dependent on the ValueKind of the set itself
-      returnValueKind: ValueKind.Mutable,
-      aliasing: {
-        receiver: '@receiver',
-        params: [],
-        rest: '@rest',
-        returns: '@returns',
-        temporaries: [],
-        effects: [
-          // Set.add returns the receiver Set
-          {
-            kind: 'Assign',
-            from: '@receiver',
-            into: '@returns',
-          },
-          // Set.add mutates the set itself
-          {
-            kind: 'Mutate',
-            value: '@receiver',
-          },
-          // Captures the rest params into the set
-          {
-            kind: 'Capture',
-            from: '@rest',
-            into: '@receiver',
-          },
-        ],
-      },
-    }),
-  ],
-  [
-    /**
-     * clear()
-     * Parameters none
-     * Returns undefined
-     */
-    'clear',
-    addFunction(BUILTIN_SHAPES, [], {
-      positionalParams: [],
-      restParam: null,
-      returnType: PRIMITIVE_TYPE,
-      calleeEffect: Effect.Store,
-      returnValueKind: ValueKind.Primitive,
-    }),
-  ],
-  [
-    /**
-     * setInstance.delete(value)
-     * Returns true if value was already in Set; otherwise false.
-     */
-    'delete',
-    addFunction(BUILTIN_SHAPES, [], {
-      positionalParams: [Effect.Read],
-      restParam: null,
-      returnType: PRIMITIVE_TYPE,
-      calleeEffect: Effect.Store,
-      returnValueKind: ValueKind.Primitive,
-    }),
-  ],
-  [
-    'has',
-    addFunction(BUILTIN_SHAPES, [], {
-      positionalParams: [Effect.Read],
-      restParam: null,
-      returnType: PRIMITIVE_TYPE,
-      calleeEffect: Effect.Read,
-      returnValueKind: ValueKind.Primitive,
-    }),
-  ],
-  ['size', PRIMITIVE_TYPE],
-  [
-    /**
-     * difference(other)
-     * Parameters
-     *   other: A Set object, or set-like object.
-     * Returns a new Set object containing elements in this set but not in the other set.
-     */
-    'difference',
-    addFunction(BUILTIN_SHAPES, [], {
-      positionalParams: [Effect.Capture],
-      restParam: null,
-      returnType: {kind: 'Object', shapeId: BuiltInSetId},
-      calleeEffect: Effect.Capture,
-      returnValueKind: ValueKind.Mutable,
-    }),
-  ],
-  [
-    /**
-     * union(other)
-     * Parameters
-     *   other: A Set object, or set-like object.
-     * Returns a new Set object containing elements in either this set or the other set.
-     */
-    'union',
-    addFunction(BUILTIN_SHAPES, [], {
-      positionalParams: [Effect.Capture],
-      restParam: null,
-      returnType: {kind: 'Object', shapeId: BuiltInSetId},
-      calleeEffect: Effect.Capture,
-      returnValueKind: ValueKind.Mutable,
-    }),
-  ],
-  [
-    /**
-     * symmetricalDifference(other)
-     * Parameters
-     *   other: A Set object, or set-like object.
-     * A new Set object containing elements which are in either this set or the other set, but not in both.
-     */
-    'symmetricalDifference',
-    addFunction(BUILTIN_SHAPES, [], {
-      positionalParams: [Effect.Capture],
-      restParam: null,
-      returnType: {kind: 'Object', shapeId: BuiltInSetId},
-      calleeEffect: Effect.Capture,
-      returnValueKind: ValueKind.Mutable,
-    }),
-  ],
-  [
-    /**
-     * isSubsetOf(other)
-     * Parameters
-     *   other: A Set object, or set-like object.
-     * Returns true if all elements in this set are also in the other set, and false otherwise.
-     */
-    'isSubsetOf',
-    addFunction(BUILTIN_SHAPES, [], {
-      positionalParams: [Effect.Read],
-      restParam: null,
-      returnType: PRIMITIVE_TYPE,
-      calleeEffect: Effect.Read,
-      returnValueKind: ValueKind.Primitive,
-    }),
-  ],
-  [
-    /**
-     * isSupersetOf(other)
-     * Parameters
-     *  other: A Set object, or set-like object.
-     * Returns true if all elements in the other set are also in this set, and false otherwise.
-     */
-    'isSupersetOf',
-    addFunction(BUILTIN_SHAPES, [], {
-      positionalParams: [Effect.Read],
-      restParam: null,
-      returnType: PRIMITIVE_TYPE,
-      calleeEffect: Effect.Read,
-      returnValueKind: ValueKind.Primitive,
-    }),
-  ],
-  [
-    /**
-     * forEach(callbackFn)
-     * forEach(callbackFn, thisArg)
-     */
-    'forEach',
-    addFunction(BUILTIN_SHAPES, [], {
-      /**
-       * see Array.map explanation for why arguments are marked `ConditionallyMutate`
-       */
-      positionalParams: [],
-      restParam: Effect.ConditionallyMutate,
-      returnType: PRIMITIVE_TYPE,
-      calleeEffect: Effect.ConditionallyMutate,
-      returnValueKind: ValueKind.Primitive,
-      noAlias: true,
-      mutableOnlyIfOperandsAreMutable: true,
-    }),
-  ],
-  /**
-   * Iterators
-   */
-  [
-    'entries',
-    addFunction(BUILTIN_SHAPES, [], {
-      positionalParams: [],
-      restParam: null,
-      returnType: {kind: 'Poly'},
-      calleeEffect: Effect.Capture,
-      returnValueKind: ValueKind.Mutable,
-    }),
-  ],
-  [
-    'keys',
-    addFunction(BUILTIN_SHAPES, [], {
-      positionalParams: [],
-      restParam: null,
-      returnType: {kind: 'Poly'},
-      calleeEffect: Effect.Capture,
-      returnValueKind: ValueKind.Mutable,
-    }),
-  ],
-  [
-    'values',
-    addFunction(BUILTIN_SHAPES, [], {
-      positionalParams: [],
-      restParam: null,
-      returnType: {kind: 'Poly'},
-      calleeEffect: Effect.Capture,
-      returnValueKind: ValueKind.Mutable,
-    }),
-  ],
-]);
-addObject(BUILTIN_SHAPES, BuiltInMapId, [
-  [
-    /**
-     * clear()
-     * Parameters none
-     * Returns undefined
-     */
-    'clear',
-    addFunction(BUILTIN_SHAPES, [], {
-      positionalParams: [],
-      restParam: null,
-      returnType: PRIMITIVE_TYPE,
-      calleeEffect: Effect.Store,
-      returnValueKind: ValueKind.Primitive,
-    }),
-  ],
-  [
-    'delete',
-    addFunction(BUILTIN_SHAPES, [], {
-      positionalParams: [Effect.Read],
-      restParam: null,
-      returnType: PRIMITIVE_TYPE,
-      calleeEffect: Effect.Store,
-      returnValueKind: ValueKind.Primitive,
-    }),
-  ],
-  [
-    'get',
-    addFunction(BUILTIN_SHAPES, [], {
-      positionalParams: [Effect.Read],
-      restParam: null,
-      returnType: {kind: 'Poly'},
-      calleeEffect: Effect.Capture,
-      returnValueKind: ValueKind.Mutable,
-    }),
-  ],
-  [
-    'has',
-    addFunction(BUILTIN_SHAPES, [], {
-      positionalParams: [Effect.Read],
-      restParam: null,
-      returnType: PRIMITIVE_TYPE,
-      calleeEffect: Effect.Read,
-      returnValueKind: ValueKind.Primitive,
-    }),
-  ],
-  [
-    /**
-     * Params
-     *   key: the key of the element to add to the Map object. The key may be
-     *   any JavaScript type (any primitive value or any type of JavaScript
-     *   object).
-     *   value: the value of the element to add to the Map object.
-     * Returns the Map object.
-     */
-    'set',
-    addFunction(BUILTIN_SHAPES, [], {
-      positionalParams: [Effect.Capture, Effect.Capture],
-      restParam: null,
-      returnType: {kind: 'Object', shapeId: BuiltInMapId},
-      calleeEffect: Effect.Store,
-      returnValueKind: ValueKind.Mutable,
-    }),
-  ],
-  ['size', PRIMITIVE_TYPE],
-  [
-    'forEach',
-    addFunction(BUILTIN_SHAPES, [], {
-      /**
-       * see Array.map explanation for why arguments are marked `ConditionallyMutate`
-       */
-      positionalParams: [],
-      restParam: Effect.ConditionallyMutate,
-      returnType: PRIMITIVE_TYPE,
-      calleeEffect: Effect.ConditionallyMutate,
-      returnValueKind: ValueKind.Primitive,
-      noAlias: true,
-      mutableOnlyIfOperandsAreMutable: true,
-    }),
-  ],
-  /**
-   * Iterators
-   */
-  [
-    'entries',
-    addFunction(BUILTIN_SHAPES, [], {
-      positionalParams: [],
-      restParam: null,
-      returnType: {kind: 'Poly'},
-      calleeEffect: Effect.Capture,
-      returnValueKind: ValueKind.Mutable,
-    }),
-  ],
-  [
-    'keys',
-    addFunction(BUILTIN_SHAPES, [], {
-      positionalParams: [],
-      restParam: null,
-      returnType: {kind: 'Poly'},
-      calleeEffect: Effect.Capture,
-      returnValueKind: ValueKind.Mutable,
-    }),
-  ],
-  [
-    'values',
-    addFunction(BUILTIN_SHAPES, [], {
-      positionalParams: [],
-      restParam: null,
-      returnType: {kind: 'Poly'},
-      calleeEffect: Effect.Capture,
-      returnValueKind: ValueKind.Mutable,
-    }),
-  ],
-]);
-
-addObject(BUILTIN_SHAPES, BuiltInWeakSetId, [
-  [
-    /**
-     * add(value)
-     * Parameters
-     *   value: the value of the element to add to the Set object.
-     * Returns the Set object with added value.
-     */
-    'add',
-    addFunction(BUILTIN_SHAPES, [], {
-      positionalParams: [Effect.Capture],
-      restParam: null,
-      returnType: {kind: 'Object', shapeId: BuiltInWeakSetId},
-      calleeEffect: Effect.Store,
-      // returnValueKind is technically dependent on the ValueKind of the set itself
-      returnValueKind: ValueKind.Mutable,
-    }),
-  ],
-  [
-    /**
-     * setInstance.delete(value)
-     * Returns true if value was already in Set; otherwise false.
-     */
-    'delete',
-    addFunction(BUILTIN_SHAPES, [], {
-      positionalParams: [Effect.Read],
-      restParam: null,
-      returnType: PRIMITIVE_TYPE,
-      calleeEffect: Effect.Store,
-      returnValueKind: ValueKind.Primitive,
-    }),
-  ],
-  [
-    'has',
-    addFunction(BUILTIN_SHAPES, [], {
-      positionalParams: [Effect.Read],
-      restParam: null,
-      returnType: PRIMITIVE_TYPE,
-      calleeEffect: Effect.Read,
-      returnValueKind: ValueKind.Primitive,
-    }),
-  ],
-]);
-
-addObject(BUILTIN_SHAPES, BuiltInWeakMapId, [
-  [
-    'delete',
-    addFunction(BUILTIN_SHAPES, [], {
-      positionalParams: [Effect.Read],
-      restParam: null,
-      returnType: PRIMITIVE_TYPE,
-      calleeEffect: Effect.Store,
-      returnValueKind: ValueKind.Primitive,
-    }),
-  ],
-  [
-    'get',
-    addFunction(BUILTIN_SHAPES, [], {
-      positionalParams: [Effect.Read],
-      restParam: null,
-      returnType: {kind: 'Poly'},
-      calleeEffect: Effect.Capture,
-      returnValueKind: ValueKind.Mutable,
-    }),
-  ],
-  [
-    'has',
-    addFunction(BUILTIN_SHAPES, [], {
-      positionalParams: [Effect.Read],
-      restParam: null,
-      returnType: PRIMITIVE_TYPE,
-      calleeEffect: Effect.Read,
-      returnValueKind: ValueKind.Primitive,
-    }),
-  ],
-  [
-    /**
-     * Params
-     *   key: the key of the element to add to the Map object. The key may be
-     *   any JavaScript type (any primitive value or any type of JavaScript
-     *   object).
-     *   value: the value of the element to add to the Map object.
-     * Returns the Map object.
-     */
-    'set',
-    addFunction(BUILTIN_SHAPES, [], {
-      positionalParams: [Effect.Capture, Effect.Capture],
-      restParam: null,
-      returnType: {kind: 'Object', shapeId: BuiltInWeakMapId},
-      calleeEffect: Effect.Store,
-      returnValueKind: ValueKind.Mutable,
-    }),
-  ],
-]);
-
 addObject(BUILTIN_SHAPES, BuiltInUseStateId, [
   ['0', {kind: 'Poly'}],
   [
@@ -1211,45 +535,6 @@ addObject(BUILTIN_SHAPES, BuiltInRefValueId, [
   ['*', {kind: 'Object', shapeId: BuiltInRefValueId}],
 ]);
 
-addObject(BUILTIN_SHAPES, ReanimatedSharedValueId, []);
-
-addFunction(
-  BUILTIN_SHAPES,
-  [],
-  {
-    positionalParams: [],
-    restParam: Effect.ConditionallyMutate,
-    returnType: {kind: 'Poly'},
-    calleeEffect: Effect.ConditionallyMutate,
-    returnValueKind: ValueKind.Mutable,
-  },
-  BuiltinEffectEventId,
-);
-
-/**
- * MixedReadOnly =
- *   | primitive
- *   | simple objects (Record<string, MixedReadOnly>)
- *   | Array<MixedReadOnly>
- *
- * APIs such as Relay — but also Flux and other data stores — often return a
- * union of types with some interesting properties in terms of analysis.
- *
- * Given this constraint, if data came from Relay, then we should be able to
- * infer things like `data.items.map(): Array`. That may seem like a leap at
- * first but remember, we assume you're not patching builtins. Thus the only way
- * data.items.map can exist and be a function, given the above set of data types
- * and builtin JS methods, is if `data.items` was an Array, and `data.items.map`
- * is therefore calling Array.prototype.map. Then we know that function returns
- * an Array as well. This relies on the fact that map() is being called, so if
- * data.items was some other type it would error at runtime - so it's sound.
- *
- * Note that this shape is currently only used for hook return values, which
- * means that it's safe to type aliasing method-call return kinds as `Frozen`.
- *
- * Also note that all newly created arrays from method-calls (e.g. `.map`)
- * have the appropriate mutable `BuiltInArray` shape
- */
 addObject(BUILTIN_SHAPES, BuiltInMixedReadonlyId, [
   [
     'toString',
@@ -1261,36 +546,6 @@ addObject(BUILTIN_SHAPES, BuiltInMixedReadonlyId, [
       returnValueKind: ValueKind.Primitive,
     }),
   ],
-  [
-    'indexOf',
-    addFunction(BUILTIN_SHAPES, [], {
-      positionalParams: [],
-      restParam: Effect.Read,
-      returnType: {kind: 'Primitive'},
-      calleeEffect: Effect.Read,
-      returnValueKind: ValueKind.Primitive,
-    }),
-  ],
-  [
-    'includes',
-    addFunction(BUILTIN_SHAPES, [], {
-      positionalParams: [],
-      restParam: Effect.Read,
-      returnType: {kind: 'Primitive'},
-      calleeEffect: Effect.Read,
-      returnValueKind: ValueKind.Primitive,
-    }),
-  ],
-  [
-    'at',
-    addFunction(BUILTIN_SHAPES, [], {
-      positionalParams: [Effect.Read],
-      restParam: null,
-      returnType: {kind: 'Object', shapeId: BuiltInMixedReadonlyId},
-      calleeEffect: Effect.Capture,
-      returnValueKind: ValueKind.Frozen,
-    }),
-  ],
   [
     'map',
     addFunction(BUILTIN_SHAPES, [], {
@@ -1387,9 +642,9 @@ addObject(BUILTIN_SHAPES, BuiltInMixedReadonlyId, [
     addFunction(BUILTIN_SHAPES, [], {
       positionalParams: [],
       restParam: Effect.ConditionallyMutate,
-      returnType: {kind: 'Object', shapeId: BuiltInMixedReadonlyId},
+      returnType: {kind: 'Poly'},
       calleeEffect: Effect.ConditionallyMutate,
-      returnValueKind: ValueKind.Frozen,
+      returnValueKind: ValueKind.Mutable,
       noAlias: true,
       mutableOnlyIfOperandsAreMutable: true,
     }),
@@ -1444,53 +699,6 @@ export const DefaultNonmutatingHook = addHook(
     calleeEffect: Effect.Read,
     hookKind: 'Custom',
     returnValueKind: ValueKind.Frozen,
-    aliasing: {
-      receiver: '@receiver',
-      params: [],
-      rest: '@rest',
-      returns: '@returns',
-      temporaries: [],
-      effects: [
-        // Freeze the arguments
-        {
-          kind: 'Freeze',
-          value: '@rest',
-          reason: ValueReason.HookCaptured,
-        },
-        // Returns a frozen value
-        {
-          kind: 'Create',
-          into: '@returns',
-          value: ValueKind.Frozen,
-          reason: ValueReason.HookReturn,
-        },
-        // May alias any arguments into the return
-        {
-          kind: 'Alias',
-          from: '@rest',
-          into: '@returns',
-        },
-      ],
-    },
   },
   'DefaultNonmutatingHook',
 );
-
-export function signatureArgument(id: number): Place {
-  const place: Place = {
-    kind: 'Identifier',
-    effect: Effect.Unknown,
-    loc: GeneratedSource,
-    reactive: false,
-    identifier: {
-      declarationId: makeDeclarationId(id),
-      id: makeIdentifierId(id),
-      loc: GeneratedSource,
-      mutableRange: {start: makeInstructionId(0), end: makeInstructionId(0)},
-      name: null,
-      scope: null,
-      type: makeType(),
-    },
-  };
-  return place;
-}

compiler/packages/babel-plugin-react-compiler/src/HIR/PrintHIR.ts

@@ -5,6 +5,7 @@
  * LICENSE file in the root directory of this source tree.
  */
 
+import generate from '@babel/generator';
 import {CompilerError} from '../CompilerError';
 import {printReactiveScopeSummary} from '../ReactiveScopes/PrintReactiveFunction';
 import DisjointSet from '../Utils/DisjointSet';
@@ -34,7 +35,6 @@ import type {
   Type,
 } from './HIR';
 import {GotoVariant, InstructionKind} from './HIR';
-import {AliasingEffect, AliasingSignature} from '../Inference/AliasingEffects';
 
 export type Options = {
   indent: number;
@@ -53,8 +53,6 @@ export function printFunction(fn: HIRFunction): string {
   let definition = '';
   if (fn.id !== null) {
     definition += fn.id;
-  } else {
-    definition += '<<anonymous>>';
   }
   if (fn.params.length !== 0) {
     definition +=
@@ -69,13 +67,13 @@ export function printFunction(fn: HIRFunction): string {
         })
         .join(', ') +
       ')';
-  } else {
-    definition += '()';
   }
-  definition += `: ${printPlace(fn.returns)}`;
-  output.push(definition);
-  output.push(...fn.directives);
+  if (definition.length !== 0) {
+    output.push(definition);
+  }
+  output.push(printType(fn.returnType));
   output.push(printHIR(fn.body));
+  output.push(...fn.directives);
   return output.join('\n');
 }
 
@@ -153,10 +151,7 @@ export function printMixedHIR(
 
 export function printInstruction(instr: ReactiveInstruction): string {
   const id = `[${instr.id}]`;
-  let value = printInstructionValue(instr.value);
-  if (instr.effects != null) {
-    value += `\n    ${instr.effects.map(printAliasingEffect).join('\n    ')}`;
-  }
+  const value = printInstructionValue(instr.value);
 
   if (instr.lvalue !== null) {
     return `${id} ${printPlace(instr.lvalue)} = ${value}`;
@@ -215,12 +210,9 @@ export function printTerminal(terminal: Terminal): Array<string> | string {
       break;
     }
     case 'return': {
-      value = `[${terminal.id}] Return ${terminal.returnVariant}${
+      value = `[${terminal.id}] Return${
         terminal.value != null ? ' ' + printPlace(terminal.value) : ''
       }`;
-      if (terminal.effects != null) {
-        value += `\n    ${terminal.effects.map(printAliasingEffect).join('\n    ')}`;
-      }
       break;
     }
     case 'goto': {
@@ -289,9 +281,6 @@ export function printTerminal(terminal: Terminal): Array<string> | string {
     }
     case 'maybe-throw': {
       value = `[${terminal.id}] MaybeThrow continuation=bb${terminal.continuation} handler=bb${terminal.handler}`;
-      if (terminal.effects != null) {
-        value += `\n    ${terminal.effects.map(printAliasingEffect).join('\n    ')}`;
-      }
       break;
     }
     case 'scope': {
@@ -341,9 +330,6 @@ function printObjectPropertyKey(key: ObjectPropertyKey): string {
     case 'computed': {
       return `[${printPlace(key.name)}]`;
     }
-    case 'number': {
-      return String(key.name);
-    }
   }
 }
 
@@ -465,7 +451,7 @@ export function printInstructionValue(instrValue: ReactiveValue): string {
       break;
     }
     case 'UnsupportedNode': {
-      value = `UnsupportedNode ${instrValue.node.type}`;
+      value = `UnsupportedNode(${generate(instrValue.node).code})`;
       break;
     }
     case 'LoadLocal': {
@@ -566,11 +552,8 @@ export function printInstructionValue(instrValue: ReactiveValue): string {
             }
           })
           .join(', ') ?? '';
-      const aliasingEffects =
-        instrValue.loweredFunc.func.aliasingEffects
-          ?.map(printAliasingEffect)
-          ?.join(', ') ?? '';
-      value = `${kind} ${name} @context[${context}] @effects[${effects}] @aliasingEffects=[${aliasingEffects}]\n${fn}`;
+      const type = printType(instrValue.loweredFunc.func.returnType).trim();
+      value = `${kind} ${name} @context[${context}] @effects[${effects}]${type !== '' ? ` return${type}` : ''}:\n${fn}`;
       break;
     }
     case 'TaggedTemplateExpression': {
@@ -714,7 +697,7 @@ export function printInstructionValue(instrValue: ReactiveValue): string {
       break;
     }
     case 'FinishMemoize': {
-      value = `FinishMemoize decl=${printPlace(instrValue.decl)}${instrValue.pruned ? ' pruned' : ''}`;
+      value = `FinishMemoize decl=${printPlace(instrValue.decl)}`;
       break;
     }
     default: {
@@ -936,110 +919,3 @@ function getFunctionName(
       return defaultValue;
   }
 }
-
-export function printAliasingEffect(effect: AliasingEffect): string {
-  switch (effect.kind) {
-    case 'Assign': {
-      return `Assign ${printPlaceForAliasEffect(effect.into)} = ${printPlaceForAliasEffect(effect.from)}`;
-    }
-    case 'Alias': {
-      return `Alias ${printPlaceForAliasEffect(effect.into)} <- ${printPlaceForAliasEffect(effect.from)}`;
-    }
-    case 'MaybeAlias': {
-      return `MaybeAlias ${printPlaceForAliasEffect(effect.into)} <- ${printPlaceForAliasEffect(effect.from)}`;
-    }
-    case 'Capture': {
-      return `Capture ${printPlaceForAliasEffect(effect.into)} <- ${printPlaceForAliasEffect(effect.from)}`;
-    }
-    case 'ImmutableCapture': {
-      return `ImmutableCapture ${printPlaceForAliasEffect(effect.into)} <- ${printPlaceForAliasEffect(effect.from)}`;
-    }
-    case 'Create': {
-      return `Create ${printPlaceForAliasEffect(effect.into)} = ${effect.value}`;
-    }
-    case 'CreateFrom': {
-      return `Create ${printPlaceForAliasEffect(effect.into)} = kindOf(${printPlaceForAliasEffect(effect.from)})`;
-    }
-    case 'CreateFunction': {
-      return `Function ${printPlaceForAliasEffect(effect.into)} = Function captures=[${effect.captures.map(printPlaceForAliasEffect).join(', ')}]`;
-    }
-    case 'Apply': {
-      const receiverCallee =
-        effect.receiver.identifier.id === effect.function.identifier.id
-          ? printPlaceForAliasEffect(effect.receiver)
-          : `${printPlaceForAliasEffect(effect.receiver)}.${printPlaceForAliasEffect(effect.function)}`;
-      const args = effect.args
-        .map(arg => {
-          if (arg.kind === 'Identifier') {
-            return printPlaceForAliasEffect(arg);
-          } else if (arg.kind === 'Hole') {
-            return ' ';
-          }
-          return `...${printPlaceForAliasEffect(arg.place)}`;
-        })
-        .join(', ');
-      let signature = '';
-      if (effect.signature != null) {
-        if (effect.signature.aliasing != null) {
-          signature = printAliasingSignature(effect.signature.aliasing);
-        } else {
-          signature = JSON.stringify(effect.signature, null, 2);
-        }
-      }
-      return `Apply ${printPlaceForAliasEffect(effect.into)} = ${receiverCallee}(${args})${signature != '' ? '\n     ' : ''}${signature}`;
-    }
-    case 'Freeze': {
-      return `Freeze ${printPlaceForAliasEffect(effect.value)} ${effect.reason}`;
-    }
-    case 'Mutate':
-    case 'MutateConditionally':
-    case 'MutateTransitive':
-    case 'MutateTransitiveConditionally': {
-      return `${effect.kind} ${printPlaceForAliasEffect(effect.value)}`;
-    }
-    case 'MutateFrozen': {
-      return `MutateFrozen ${printPlaceForAliasEffect(effect.place)} reason=${JSON.stringify(effect.error.category)}`;
-    }
-    case 'MutateGlobal': {
-      return `MutateGlobal ${printPlaceForAliasEffect(effect.place)} reason=${JSON.stringify(effect.error.category)}`;
-    }
-    case 'Impure': {
-      return `Impure ${printPlaceForAliasEffect(effect.place)} reason=${JSON.stringify(effect.error.category)}`;
-    }
-    case 'Render': {
-      return `Render ${printPlaceForAliasEffect(effect.place)}`;
-    }
-    default: {
-      assertExhaustive(effect, `Unexpected kind '${(effect as any).kind}'`);
-    }
-  }
-}
-
-function printPlaceForAliasEffect(place: Place): string {
-  return printIdentifier(place.identifier);
-}
-
-export function printAliasingSignature(signature: AliasingSignature): string {
-  const tokens: Array<string> = ['function '];
-  if (signature.temporaries.length !== 0) {
-    tokens.push('<');
-    tokens.push(
-      signature.temporaries.map(temp => `$${temp.identifier.id}`).join(', '),
-    );
-    tokens.push('>');
-  }
-  tokens.push('(');
-  tokens.push('this=$' + String(signature.receiver));
-  for (const param of signature.params) {
-    tokens.push(', $' + String(param));
-  }
-  if (signature.rest != null) {
-    tokens.push(`, ...$${String(signature.rest)}`);
-  }
-  tokens.push('): ');
-  tokens.push('$' + String(signature.returns) + ':');
-  for (const effect of signature.effects) {
-    tokens.push('\n  ' + printAliasingEffect(effect));
-  }
-  return tokens.join('');
-}

compiler/packages/babel-plugin-react-compiler/src/HIR/PropagateScopeDependenciesHIR.ts

@@ -1,10 +1,3 @@
-/**
- * Copyright (c) Meta Platforms, Inc. and affiliates.
- *
- * This source code is licensed under the MIT license found in the
- * LICENSE file in the root directory of this source tree.
- */
-
 import {
   ScopeId,
   HIRFunction,
@@ -30,7 +23,6 @@ import {
   FunctionExpression,
   ObjectMethod,
   PropertyLiteral,
-  convertHoistedLValueKind,
 } from './HIR';
 import {
   collectHoistablePropertyLoads,
@@ -117,7 +109,7 @@ export function propagateScopeDependenciesHIR(fn: HIRFunction): void {
   }
 }
 
-export function findTemporariesUsedOutsideDeclaringScope(
+function findTemporariesUsedOutsideDeclaringScope(
   fn: HIRFunction,
 ): ReadonlySet<DeclarationId> {
   /*
@@ -247,18 +239,12 @@ function isLoadContextMutable(
   id: InstructionId,
 ): instrValue is LoadContext {
   if (instrValue.kind === 'LoadContext') {
-    /**
-     * Not all context variables currently have scopes due to limitations of
-     * mutability analysis for function expressions.
-     *
-     * Currently, many function expressions references are inferred to be
-     * 'Read' | 'Freeze' effects which don't replay mutable effects of captured
-     * context.
-     */
-    return (
-      instrValue.place.identifier.scope != null &&
-      id >= instrValue.place.identifier.scope.range.end
-    );
+    CompilerError.invariant(instrValue.place.identifier.scope != null, {
+      reason:
+        '[PropagateScopeDependencies] Expected all context variables to be assigned a scope',
+      loc: instrValue.loc,
+    });
+    return id >= instrValue.place.identifier.scope.range.end;
   }
   return false;
 }
@@ -316,7 +302,6 @@ function collectTemporariesSidemapImpl(
         ) {
           temporaries.set(lvalue.identifier.id, {
             identifier: value.place.identifier,
-            reactive: value.place.reactive,
             path: [],
           });
         }
@@ -370,13 +355,11 @@ function getProperty(
   if (resolvedDependency == null) {
     property = {
       identifier: object.identifier,
-      reactive: object.reactive,
       path: [{property: propertyName, optional}],
     };
   } else {
     property = {
       identifier: resolvedDependency.identifier,
-      reactive: resolvedDependency.reactive,
       path: [...resolvedDependency.path, {property: propertyName, optional}],
     };
   }
@@ -388,7 +371,7 @@ type Decl = {
   scope: Stack<ReactiveScope>;
 };
 
-export class DependencyCollectionContext {
+class Context {
   #declarations: Map<DeclarationId, Decl> = new Map();
   #reassignments: Map<Identifier, Decl> = new Map();
 
@@ -481,9 +464,6 @@ export class DependencyCollectionContext {
     }
     this.#reassignments.set(identifier, decl);
   }
-  hasDeclared(identifier: Identifier): boolean {
-    return this.#declarations.has(identifier.declarationId);
-  }
 
   // Checks if identifier is a valid dependency in the current scope
   #checkValidDependency(maybeDependency: ReactiveScopeDependency): boolean {
@@ -535,7 +515,6 @@ export class DependencyCollectionContext {
     this.visitDependency(
       this.#temporaries.get(place.identifier.id) ?? {
         identifier: place.identifier,
-        reactive: place.reactive,
         path: [],
       },
     );
@@ -600,7 +579,6 @@ export class DependencyCollectionContext {
     ) {
       maybeDependency = {
         identifier: maybeDependency.identifier,
-        reactive: maybeDependency.reactive,
         path: [],
       };
     }
@@ -622,11 +600,7 @@ export class DependencyCollectionContext {
         identifier =>
           identifier.declarationId === place.identifier.declarationId,
       ) &&
-      this.#checkValidDependency({
-        identifier: place.identifier,
-        reactive: place.reactive,
-        path: [],
-      })
+      this.#checkValidDependency({identifier: place.identifier, path: []})
     ) {
       currentScope.reassignments.add(place.identifier);
     }
@@ -664,10 +638,7 @@ enum HIRValue {
   Terminal,
 }
 
-export function handleInstruction(
-  instr: Instruction,
-  context: DependencyCollectionContext,
-): void {
+function handleInstruction(instr: Instruction, context: Context): void {
   const {id, value, lvalue} = instr;
   context.declare(lvalue.identifier, {
     id,
@@ -691,21 +662,21 @@ export function handleInstruction(
     });
   } else if (value.kind === 'DeclareLocal' || value.kind === 'DeclareContext') {
     /*
-     * Some variables may be declared and never initialized. We need to retain
-     * (and hoist) these declarations if they are included in a reactive scope.
-     * One approach is to simply add all `DeclareLocal`s as scope declarations.
-     *
-     * Context variables with hoisted declarations only become live after their
-     * first assignment. We only declare real DeclareLocal / DeclareContext
-     * instructions (not hoisted ones) to avoid generating dependencies on
-     * hoisted declarations.
+     * Some variables may be declared and never initialized. We need
+     * to retain (and hoist) these declarations if they are included
+     * in a reactive scope. One approach is to simply add all `DeclareLocal`s
+     * as scope declarations.
      */
-    if (convertHoistedLValueKind(value.lvalue.kind) === null) {
-      context.declare(value.lvalue.place.identifier, {
-        id,
-        scope: context.currentScope,
-      });
-    }
+
+    /*
+     * We add context variable declarations here, not at `StoreContext`, since
+     * context Store / Loads are modeled as reads and mutates to the underlying
+     * variable reference (instead of through intermediate / inlined temporaries)
+     */
+    context.declare(value.lvalue.place.identifier, {
+      id,
+      scope: context.currentScope,
+    });
   } else if (value.kind === 'Destructure') {
     context.visitOperand(value.value);
     for (const place of eachPatternOperand(value.lvalue.pattern)) {
@@ -717,26 +688,6 @@ export function handleInstruction(
         scope: context.currentScope,
       });
     }
-  } else if (value.kind === 'StoreContext') {
-    /**
-     * Some StoreContext variables have hoisted declarations. If we're storing
-     * to a context variable that hasn't yet been declared, the StoreContext is
-     * the declaration.
-     * (see corresponding logic in PruneHoistedContext)
-     */
-    if (
-      !context.hasDeclared(value.lvalue.place.identifier) ||
-      value.lvalue.kind !== InstructionKind.Reassign
-    ) {
-      context.declare(value.lvalue.place.identifier, {
-        id,
-        scope: context.currentScope,
-      });
-    }
-
-    for (const operand of eachInstructionValueOperand(value)) {
-      context.visitOperand(operand);
-    }
   } else {
     for (const operand of eachInstructionValueOperand(value)) {
       context.visitOperand(operand);
@@ -750,7 +701,7 @@ function collectDependencies(
   temporaries: ReadonlyMap<IdentifierId, ReactiveScopeDependency>,
   processedInstrsInOptional: ReadonlySet<Instruction | Terminal>,
 ): Map<ReactiveScope, Array<ReactiveScopeDependency>> {
-  const context = new DependencyCollectionContext(
+  const context = new Context(
     usedOutsideDeclaringScope,
     temporaries,
     processedInstrsInOptional,

compiler/packages/babel-plugin-react-compiler/src/HIR/PruneUnusedLabelsHIR.ts

@@ -1,10 +1,3 @@
-/**
- * Copyright (c) Meta Platforms, Inc. and affiliates.
- *
- * This source code is licensed under the MIT license found in the
- * LICENSE file in the root directory of this source tree.
- */
-
 import {CompilerError} from '..';
 import {BlockId, GotoVariant, HIRFunction} from './HIR';
 

compiler/packages/babel-plugin-react-compiler/src/HIR/ScopeDependencyUtils.ts

@@ -1,285 +0,0 @@
-import {
-  Place,
-  ReactiveScopeDependency,
-  Identifier,
-  makeInstructionId,
-  InstructionKind,
-  GeneratedSource,
-  BlockId,
-  makeTemporaryIdentifier,
-  Effect,
-  GotoVariant,
-  HIR,
-} from './HIR';
-import {CompilerError} from '../CompilerError';
-import {Environment} from './Environment';
-import HIRBuilder from './HIRBuilder';
-import {lowerValueToTemporary} from './BuildHIR';
-
-type DependencyInstructions = {
-  place: Place;
-  value: HIR;
-  exitBlockId: BlockId;
-};
-
-export function buildDependencyInstructions(
-  dep: ReactiveScopeDependency,
-  env: Environment,
-): DependencyInstructions {
-  const builder = new HIRBuilder(env, {
-    entryBlockKind: 'value',
-  });
-  let dependencyValue: Identifier;
-  if (dep.path.every(path => !path.optional)) {
-    dependencyValue = writeNonOptionalDependency(dep, env, builder);
-  } else {
-    dependencyValue = writeOptionalDependency(dep, builder, null);
-  }
-
-  const exitBlockId = builder.terminate(
-    {
-      kind: 'unsupported',
-      loc: GeneratedSource,
-      id: makeInstructionId(0),
-    },
-    null,
-  );
-  return {
-    place: {
-      kind: 'Identifier',
-      identifier: dependencyValue,
-      effect: Effect.Freeze,
-      reactive: dep.reactive,
-      loc: GeneratedSource,
-    },
-    value: builder.build(),
-    exitBlockId,
-  };
-}
-
-/**
- * Write instructions for a simple dependency (without optional chains)
- */
-function writeNonOptionalDependency(
-  dep: ReactiveScopeDependency,
-  env: Environment,
-  builder: HIRBuilder,
-): Identifier {
-  const loc = dep.identifier.loc;
-  let curr: Identifier = makeTemporaryIdentifier(env.nextIdentifierId, loc);
-  builder.push({
-    lvalue: {
-      identifier: curr,
-      kind: 'Identifier',
-      effect: Effect.Mutate,
-      reactive: dep.reactive,
-      loc,
-    },
-    value: {
-      kind: 'LoadLocal',
-      place: {
-        identifier: dep.identifier,
-        kind: 'Identifier',
-        effect: Effect.Freeze,
-        reactive: dep.reactive,
-        loc,
-      },
-      loc,
-    },
-    id: makeInstructionId(1),
-    loc: loc,
-    effects: null,
-  });
-
-  /**
-   * Iteratively build up dependency instructions by reading from the last written
-   * instruction.
-   */
-  for (const path of dep.path) {
-    const next = makeTemporaryIdentifier(env.nextIdentifierId, loc);
-    builder.push({
-      lvalue: {
-        identifier: next,
-        kind: 'Identifier',
-        effect: Effect.Mutate,
-        reactive: dep.reactive,
-        loc,
-      },
-      value: {
-        kind: 'PropertyLoad',
-        object: {
-          identifier: curr,
-          kind: 'Identifier',
-          effect: Effect.Freeze,
-          reactive: dep.reactive,
-          loc,
-        },
-        property: path.property,
-        loc,
-      },
-      id: makeInstructionId(1),
-      loc: loc,
-      effects: null,
-    });
-    curr = next;
-  }
-  return curr;
-}
-
-/**
- * Write a dependency into optional blocks.
- *
- * e.g. `a.b?.c.d` is written to an optional block that tests `a.b` and
- * conditionally evaluates `c.d`.
- */
-function writeOptionalDependency(
-  dep: ReactiveScopeDependency,
-  builder: HIRBuilder,
-  parentAlternate: BlockId | null,
-): Identifier {
-  const env = builder.environment;
-  /**
-   * Reserve an identifier which will be used to store the result of this
-   * dependency.
-   */
-  const dependencyValue: Place = {
-    kind: 'Identifier',
-    identifier: makeTemporaryIdentifier(env.nextIdentifierId, GeneratedSource),
-    effect: Effect.Mutate,
-    reactive: dep.reactive,
-    loc: GeneratedSource,
-  };
-
-  /**
-   * Reserve a block which is the fallthrough (and transitive successor) of this
-   * optional chain.
-   */
-  const continuationBlock = builder.reserve(builder.currentBlockKind());
-  let alternate;
-  if (parentAlternate != null) {
-    alternate = parentAlternate;
-  } else {
-    /**
-     * If an outermost alternate block has not been reserved, write one
-     *
-     * $N = Primitive undefined
-     * $M = StoreLocal $OptionalResult = $N
-     * goto fallthrough
-     */
-    alternate = builder.enter('value', () => {
-      const temp = lowerValueToTemporary(builder, {
-        kind: 'Primitive',
-        value: undefined,
-        loc: GeneratedSource,
-      });
-      lowerValueToTemporary(builder, {
-        kind: 'StoreLocal',
-        lvalue: {kind: InstructionKind.Const, place: {...dependencyValue}},
-        value: {...temp},
-        type: null,
-        loc: GeneratedSource,
-      });
-      return {
-        kind: 'goto',
-        variant: GotoVariant.Break,
-        block: continuationBlock.id,
-        id: makeInstructionId(0),
-        loc: GeneratedSource,
-      };
-    });
-  }
-
-  // Reserve the consequent block, which is the successor of the test block
-  const consequent = builder.reserve('value');
-
-  let testIdentifier: Identifier | null = null;
-  const testBlock = builder.enter('value', () => {
-    const testDependency = {
-      ...dep,
-      path: dep.path.slice(0, dep.path.length - 1),
-    };
-    const firstOptional = dep.path.findIndex(path => path.optional);
-    CompilerError.invariant(firstOptional !== -1, {
-      reason:
-        '[ScopeDependencyUtils] Internal invariant broken: expected optional path',
-      loc: dep.identifier.loc,
-      description: null,
-      suggestions: null,
-    });
-    if (firstOptional === dep.path.length - 1) {
-      // Base case: the test block is simple
-      testIdentifier = writeNonOptionalDependency(testDependency, env, builder);
-    } else {
-      // Otherwise, the test block is a nested optional chain
-      testIdentifier = writeOptionalDependency(
-        testDependency,
-        builder,
-        alternate,
-      );
-    }
-
-    return {
-      kind: 'branch',
-      test: {
-        identifier: testIdentifier,
-        effect: Effect.Freeze,
-        kind: 'Identifier',
-        loc: GeneratedSource,
-        reactive: dep.reactive,
-      },
-      consequent: consequent.id,
-      alternate,
-      id: makeInstructionId(0),
-      loc: GeneratedSource,
-      fallthrough: continuationBlock.id,
-    };
-  });
-
-  builder.enterReserved(consequent, () => {
-    CompilerError.invariant(testIdentifier !== null, {
-      reason: 'Satisfy type checker',
-      description: null,
-      loc: null,
-      suggestions: null,
-    });
-
-    lowerValueToTemporary(builder, {
-      kind: 'StoreLocal',
-      lvalue: {kind: InstructionKind.Const, place: {...dependencyValue}},
-      value: lowerValueToTemporary(builder, {
-        kind: 'PropertyLoad',
-        object: {
-          identifier: testIdentifier,
-          kind: 'Identifier',
-          effect: Effect.Freeze,
-          reactive: dep.reactive,
-          loc: GeneratedSource,
-        },
-        property: dep.path.at(-1)!.property,
-        loc: GeneratedSource,
-      }),
-      type: null,
-      loc: GeneratedSource,
-    });
-    return {
-      kind: 'goto',
-      variant: GotoVariant.Break,
-      block: continuationBlock.id,
-      id: makeInstructionId(0),
-      loc: GeneratedSource,
-    };
-  });
-  builder.terminateWithContinuation(
-    {
-      kind: 'optional',
-      optional: dep.path.at(-1)!.optional,
-      test: testBlock,
-      fallthrough: continuationBlock.id,
-      id: makeInstructionId(0),
-      loc: GeneratedSource,
-    },
-    continuationBlock,
-  );
-
-  return dependencyValue.identifier;
-}

compiler/packages/babel-plugin-react-compiler/src/HIR/TypeSchema.ts

@@ -8,12 +8,7 @@
 import {isValidIdentifier} from '@babel/types';
 import {z} from 'zod';
 import {Effect, ValueKind} from '..';
-import {
-  EffectSchema,
-  ValueKindSchema,
-  ValueReason,
-  ValueReasonSchema,
-} from './HIR';
+import {EffectSchema, ValueKindSchema} from './HIR';
 
 export type ObjectPropertiesConfig = {[key: string]: TypeConfig};
 export const ObjectPropertiesSchema: z.ZodType<ObjectPropertiesConfig> = z
@@ -36,194 +31,6 @@ export const ObjectTypeSchema: z.ZodType<ObjectTypeConfig> = z.object({
   properties: ObjectPropertiesSchema.nullable(),
 });
 
-export const LifetimeIdSchema = z.string().refine(id => id.startsWith('@'), {
-  message: "Placeholder names must start with '@'",
-});
-
-export type FreezeEffectConfig = {
-  kind: 'Freeze';
-  value: string;
-  reason: ValueReason;
-};
-
-export const FreezeEffectSchema: z.ZodType<FreezeEffectConfig> = z.object({
-  kind: z.literal('Freeze'),
-  value: LifetimeIdSchema,
-  reason: ValueReasonSchema,
-});
-
-export type MutateEffectConfig = {
-  kind: 'Mutate';
-  value: string;
-};
-
-export const MutateEffectSchema: z.ZodType<MutateEffectConfig> = z.object({
-  kind: z.literal('Mutate'),
-  value: LifetimeIdSchema,
-});
-
-export type MutateTransitiveConditionallyConfig = {
-  kind: 'MutateTransitiveConditionally';
-  value: string;
-};
-
-export const MutateTransitiveConditionallySchema: z.ZodType<MutateTransitiveConditionallyConfig> =
-  z.object({
-    kind: z.literal('MutateTransitiveConditionally'),
-    value: LifetimeIdSchema,
-  });
-
-export type CreateEffectConfig = {
-  kind: 'Create';
-  into: string;
-  value: ValueKind;
-  reason: ValueReason;
-};
-
-export const CreateEffectSchema: z.ZodType<CreateEffectConfig> = z.object({
-  kind: z.literal('Create'),
-  into: LifetimeIdSchema,
-  value: ValueKindSchema,
-  reason: ValueReasonSchema,
-});
-
-export type AssignEffectConfig = {
-  kind: 'Assign';
-  from: string;
-  into: string;
-};
-
-export const AssignEffectSchema: z.ZodType<AssignEffectConfig> = z.object({
-  kind: z.literal('Assign'),
-  from: LifetimeIdSchema,
-  into: LifetimeIdSchema,
-});
-
-export type AliasEffectConfig = {
-  kind: 'Alias';
-  from: string;
-  into: string;
-};
-
-export const AliasEffectSchema: z.ZodType<AliasEffectConfig> = z.object({
-  kind: z.literal('Alias'),
-  from: LifetimeIdSchema,
-  into: LifetimeIdSchema,
-});
-
-export type CaptureEffectConfig = {
-  kind: 'Capture';
-  from: string;
-  into: string;
-};
-
-export const CaptureEffectSchema: z.ZodType<CaptureEffectConfig> = z.object({
-  kind: z.literal('Capture'),
-  from: LifetimeIdSchema,
-  into: LifetimeIdSchema,
-});
-
-export type CreateFromEffectConfig = {
-  kind: 'CreateFrom';
-  from: string;
-  into: string;
-};
-
-export const CreateFromEffectSchema: z.ZodType<CreateFromEffectConfig> =
-  z.object({
-    kind: z.literal('CreateFrom'),
-    from: LifetimeIdSchema,
-    into: LifetimeIdSchema,
-  });
-
-export type ApplyArgConfig =
-  | string
-  | {kind: 'Spread'; place: string}
-  | {kind: 'Hole'};
-
-export const ApplyArgSchema: z.ZodType<ApplyArgConfig> = z.union([
-  LifetimeIdSchema,
-  z.object({
-    kind: z.literal('Spread'),
-    place: LifetimeIdSchema,
-  }),
-  z.object({
-    kind: z.literal('Hole'),
-  }),
-]);
-
-export type ApplyEffectConfig = {
-  kind: 'Apply';
-  receiver: string;
-  function: string;
-  mutatesFunction: boolean;
-  args: Array<ApplyArgConfig>;
-  into: string;
-};
-
-export const ApplyEffectSchema: z.ZodType<ApplyEffectConfig> = z.object({
-  kind: z.literal('Apply'),
-  receiver: LifetimeIdSchema,
-  function: LifetimeIdSchema,
-  mutatesFunction: z.boolean(),
-  args: z.array(ApplyArgSchema),
-  into: LifetimeIdSchema,
-});
-
-export type ImpureEffectConfig = {
-  kind: 'Impure';
-  place: string;
-};
-
-export const ImpureEffectSchema: z.ZodType<ImpureEffectConfig> = z.object({
-  kind: z.literal('Impure'),
-  place: LifetimeIdSchema,
-});
-
-export type AliasingEffectConfig =
-  | FreezeEffectConfig
-  | CreateEffectConfig
-  | CreateFromEffectConfig
-  | AssignEffectConfig
-  | AliasEffectConfig
-  | CaptureEffectConfig
-  | ImpureEffectConfig
-  | MutateEffectConfig
-  | MutateTransitiveConditionallyConfig
-  | ApplyEffectConfig;
-
-export const AliasingEffectSchema: z.ZodType<AliasingEffectConfig> = z.union([
-  FreezeEffectSchema,
-  CreateEffectSchema,
-  CreateFromEffectSchema,
-  AssignEffectSchema,
-  AliasEffectSchema,
-  CaptureEffectSchema,
-  ImpureEffectSchema,
-  MutateEffectSchema,
-  MutateTransitiveConditionallySchema,
-  ApplyEffectSchema,
-]);
-
-export type AliasingSignatureConfig = {
-  receiver: string;
-  params: Array<string>;
-  rest: string | null;
-  returns: string;
-  effects: Array<AliasingEffectConfig>;
-  temporaries: Array<string>;
-};
-
-export const AliasingSignatureSchema: z.ZodType<AliasingSignatureConfig> =
-  z.object({
-    receiver: LifetimeIdSchema,
-    params: z.array(LifetimeIdSchema),
-    rest: LifetimeIdSchema.nullable(),
-    returns: LifetimeIdSchema,
-    effects: z.array(AliasingEffectSchema),
-    temporaries: z.array(LifetimeIdSchema),
-  });
-
 export type FunctionTypeConfig = {
   kind: 'function';
   positionalParams: Array<Effect>;
@@ -235,7 +42,6 @@ export type FunctionTypeConfig = {
   mutableOnlyIfOperandsAreMutable?: boolean | null | undefined;
   impure?: boolean | null | undefined;
   canonicalName?: string | null | undefined;
-  aliasing?: AliasingSignatureConfig | null | undefined;
 };
 export const FunctionTypeSchema: z.ZodType<FunctionTypeConfig> = z.object({
   kind: z.literal('function'),
@@ -248,7 +54,6 @@ export const FunctionTypeSchema: z.ZodType<FunctionTypeConfig> = z.object({
   mutableOnlyIfOperandsAreMutable: z.boolean().nullable().optional(),
   impure: z.boolean().nullable().optional(),
   canonicalName: z.string().nullable().optional(),
-  aliasing: AliasingSignatureSchema.nullable().optional(),
 });
 
 export type HookTypeConfig = {
@@ -258,7 +63,6 @@ export type HookTypeConfig = {
   returnType: TypeConfig;
   returnValueKind?: ValueKind | null | undefined;
   noAlias?: boolean | null | undefined;
-  aliasing?: AliasingSignatureConfig | null | undefined;
 };
 export const HookTypeSchema: z.ZodType<HookTypeConfig> = z.object({
   kind: z.literal('hook'),
@@ -267,7 +71,6 @@ export const HookTypeSchema: z.ZodType<HookTypeConfig> = z.object({
   returnType: z.lazy(() => TypeSchema),
   returnValueKind: ValueKindSchema.nullable().optional(),
   noAlias: z.boolean().nullable().optional(),
-  aliasing: AliasingSignatureSchema.nullable().optional(),
 });
 
 export type BuiltInTypeConfig =

compiler/packages/babel-plugin-react-compiler/src/HIR/Types.ts

@@ -38,7 +38,6 @@ export type FunctionType = {
   kind: 'Function';
   shapeId: string | null;
   return: Type;
-  isConstructor: boolean;
 };
 
 export type ObjectType = {
@@ -61,15 +60,7 @@ export type PropType = {
   kind: 'Property';
   objectType: Type;
   objectName: string;
-  propertyName:
-    | {
-        kind: 'literal';
-        value: PropertyLiteral;
-      }
-    | {
-        kind: 'computed';
-        value: Type;
-      };
+  propertyName: PropertyLiteral;
 };
 
 export type ObjectMethod = {
@@ -112,7 +103,6 @@ export function duplicateType(type: Type): Type {
         kind: 'Function',
         return: duplicateType(type.return),
         shapeId: type.shapeId,
-        isConstructor: type.isConstructor,
       };
     }
     case 'Object': {

compiler/packages/babel-plugin-react-compiler/src/HIR/index.ts

@@ -17,6 +17,7 @@ export {buildReactiveScopeTerminalsHIR} from './BuildReactiveScopeTerminalsHIR';
 export {computeDominatorTree, computePostDominatorTree} from './Dominator';
 export {
   Environment,
+  parseConfigPragmaForTests,
   validateEnvironmentConfig,
   type EnvironmentConfig,
   type ExternalFunction,
@@ -31,5 +32,5 @@ export {
 } from './HIRBuilder';
 export {mergeConsecutiveBlocks} from './MergeConsecutiveBlocks';
 export {mergeOverlappingReactiveScopesHIR} from './MergeOverlappingReactiveScopesHIR';
-export {printFunction, printHIR, printFunctionWithOutlined} from './PrintHIR';
+export {printFunction, printHIR} from './PrintHIR';
 export {pruneUnusedLabelsHIR} from './PruneUnusedLabelsHIR';

compiler/packages/babel-plugin-react-compiler/src/HIR/visitors.ts

@@ -345,51 +345,6 @@ export function* eachPatternOperand(pattern: Pattern): Iterable<Place> {
   }
 }
 
-export function* eachPatternItem(
-  pattern: Pattern,
-): Iterable<Place | SpreadPattern> {
-  switch (pattern.kind) {
-    case 'ArrayPattern': {
-      for (const item of pattern.items) {
-        if (item.kind === 'Identifier') {
-          yield item;
-        } else if (item.kind === 'Spread') {
-          yield item;
-        } else if (item.kind === 'Hole') {
-          continue;
-        } else {
-          assertExhaustive(
-            item,
-            `Unexpected item kind \`${(item as any).kind}\``,
-          );
-        }
-      }
-      break;
-    }
-    case 'ObjectPattern': {
-      for (const property of pattern.properties) {
-        if (property.kind === 'ObjectProperty') {
-          yield property.place;
-        } else if (property.kind === 'Spread') {
-          yield property;
-        } else {
-          assertExhaustive(
-            property,
-            `Unexpected item kind \`${(property as any).kind}\``,
-          );
-        }
-      }
-      break;
-    }
-    default: {
-      assertExhaustive(
-        pattern,
-        `Unexpected pattern kind \`${(pattern as any).kind}\``,
-      );
-    }
-  }
-}
-
 export function mapInstructionLValues(
   instr: Instruction,
   fn: (place: Place) => Place,
@@ -777,11 +732,9 @@ export function mapTerminalSuccessors(
     case 'return': {
       return {
         kind: 'return',
-        returnVariant: terminal.returnVariant,
         loc: terminal.loc,
         value: terminal.value,
         id: makeInstructionId(0),
-        effects: terminal.effects,
       };
     }
     case 'throw': {
@@ -889,7 +842,6 @@ export function mapTerminalSuccessors(
         handler,
         id: makeInstructionId(0),
         loc: terminal.loc,
-        effects: terminal.effects,
       };
     }
     case 'try': {

compiler/packages/babel-plugin-react-compiler/src/Inference/AliasingEffects.ts

@@ -1,262 +0,0 @@
-/**
- * Copyright (c) Meta Platforms, Inc. and affiliates.
- *
- * This source code is licensed under the MIT license found in the
- * LICENSE file in the root directory of this source tree.
- */
-
-import {CompilerDiagnostic} from '../CompilerError';
-import {
-  FunctionExpression,
-  GeneratedSource,
-  Hole,
-  IdentifierId,
-  ObjectMethod,
-  Place,
-  SourceLocation,
-  SpreadPattern,
-  ValueKind,
-  ValueReason,
-} from '../HIR';
-import {FunctionSignature} from '../HIR/ObjectShape';
-import {printSourceLocation} from '../HIR/PrintHIR';
-
-/**
- * `AliasingEffect` describes a set of "effects" that an instruction/terminal has on one or
- * more values in a program. These effects include mutation of values, freezing values,
- * tracking data flow between values, and other specialized cases.
- */
-export type AliasingEffect =
-  /**
-   * Marks the given value and its direct aliases as frozen.
-   *
-   * Captured values are *not* considered frozen, because we cannot be sure that a previously
-   * captured value will still be captured at the point of the freeze.
-   *
-   * For example:
-   * const x = {};
-   * const y = [x];
-   * y.pop(); // y dosn't contain x anymore!
-   * freeze(y);
-   * mutate(x); // safe to mutate!
-   *
-   * The exception to this is FunctionExpressions - since it is impossible to change which
-   * value a function closes over[1] we can transitively freeze functions and their captures.
-   *
-   * [1] Except for `let` values that are reassigned and closed over by a function, but we
-   * handle this explicitly with StoreContext/LoadContext.
-   */
-  | {kind: 'Freeze'; value: Place; reason: ValueReason}
-  /**
-   * Mutate the value and any direct aliases (not captures). Errors if the value is not mutable.
-   */
-  | {kind: 'Mutate'; value: Place}
-  /**
-   * Mutate the value and any direct aliases (not captures), but only if the value is known mutable.
-   * This should be rare.
-   *
-   * TODO: this is only used for IteratorNext, but even then MutateTransitiveConditionally is more
-   * correct for iterators of unknown types.
-   */
-  | {kind: 'MutateConditionally'; value: Place}
-  /**
-   * Mutate the value, any direct aliases, and any transitive captures. Errors if the value is not mutable.
-   */
-  | {kind: 'MutateTransitive'; value: Place}
-  /**
-   * Mutates any of the value, its direct aliases, and its transitive captures that are mutable.
-   */
-  | {kind: 'MutateTransitiveConditionally'; value: Place}
-  /**
-   * Records information flow from `from` to `into` in cases where local mutation of the destination
-   * will *not* mutate the source:
-   *
-   * - Capture a -> b and Mutate(b) X=> (does not imply) Mutate(a)
-   * - Capture a -> b and MutateTransitive(b) => (does imply) Mutate(a)
-   *
-   * Example: `array.push(item)`. Information from item is captured into array, but there is not a
-   * direct aliasing, and local mutations of array will not modify item.
-   */
-  | {kind: 'Capture'; from: Place; into: Place}
-  /**
-   * Records information flow from `from` to `into` in cases where local mutation of the destination
-   * *will* mutate the source:
-   *
-   * - Alias a -> b and Mutate(b) => (does imply) Mutate(a)
-   * - Alias a -> b and MutateTransitive(b) => (does imply) Mutate(a)
-   *
-   * Example: `c = identity(a)`. We don't know what `identity()` returns so we can't use Assign.
-   * But we have to assume that it _could_ be returning its input, such that a local mutation of
-   * c could be mutating a.
-   */
-  | {kind: 'Alias'; from: Place; into: Place}
-
-  /**
-   * Indicates the potential for information flow from `from` to `into`. This is used for a specific
-   * case: functions with unknown signatures. If the compiler sees a call such as `foo(x)`, it has to
-   * consider several possibilities (which may depend on the arguments):
-   * - foo(x) returns a new mutable value that does not capture any information from x.
-   * - foo(x) returns a new mutable value that *does* capture information from x.
-   * - foo(x) returns x itself, ie foo is the identity function
-   *
-   * The same is true of functions that take multiple arguments: `cond(a, b, c)` could conditionally
-   * return b or c depending on the value of a.
-   *
-   * To represent this case, MaybeAlias represents the fact that an aliasing relationship could exist.
-   * Any mutations that flow through this relationship automatically become conditional.
-   */
-  | {kind: 'MaybeAlias'; from: Place; into: Place}
-
-  /**
-   * Records direct assignment: `into = from`.
-   */
-  | {kind: 'Assign'; from: Place; into: Place}
-  /**
-   * Creates a value of the given type at the given place
-   */
-  | {kind: 'Create'; into: Place; value: ValueKind; reason: ValueReason}
-  /**
-   * Creates a new value with the same kind as the starting value.
-   */
-  | {kind: 'CreateFrom'; from: Place; into: Place}
-  /**
-   * Immutable data flow, used for escape analysis. Does not influence mutable range analysis:
-   */
-  | {kind: 'ImmutableCapture'; from: Place; into: Place}
-  /**
-   * Calls the function at the given place with the given arguments either captured or aliased,
-   * and captures/aliases the result into the given place.
-   */
-  | {
-      kind: 'Apply';
-      receiver: Place;
-      function: Place;
-      mutatesFunction: boolean;
-      args: Array<Place | SpreadPattern | Hole>;
-      into: Place;
-      signature: FunctionSignature | null;
-      loc: SourceLocation;
-    }
-  /**
-   * Constructs a function value with the given captures. The mutability of the function
-   * will be determined by the mutability of the capture values when evaluated.
-   */
-  | {
-      kind: 'CreateFunction';
-      captures: Array<Place>;
-      function: FunctionExpression | ObjectMethod;
-      into: Place;
-    }
-  /**
-   * Mutation of a value known to be immutable
-   */
-  | {kind: 'MutateFrozen'; place: Place; error: CompilerDiagnostic}
-  /**
-   * Mutation of a global
-   */
-  | {
-      kind: 'MutateGlobal';
-      place: Place;
-      error: CompilerDiagnostic;
-    }
-  /**
-   * Indicates a side-effect that is not safe during render
-   */
-  | {kind: 'Impure'; place: Place; error: CompilerDiagnostic}
-  /**
-   * Indicates that a given place is accessed during render. Used to distingush
-   * hook arguments that are known to be called immediately vs those used for
-   * event handlers/effects, and for JSX values known to be called during render
-   * (tags, children) vs those that may be events/effect (other props).
-   */
-  | {
-      kind: 'Render';
-      place: Place;
-    };
-
-export function hashEffect(effect: AliasingEffect): string {
-  switch (effect.kind) {
-    case 'Apply': {
-      return [
-        effect.kind,
-        effect.receiver.identifier.id,
-        effect.function.identifier.id,
-        effect.mutatesFunction,
-        effect.args
-          .map(a => {
-            if (a.kind === 'Hole') {
-              return '';
-            } else if (a.kind === 'Identifier') {
-              return a.identifier.id;
-            } else {
-              return `...${a.place.identifier.id}`;
-            }
-          })
-          .join(','),
-        effect.into.identifier.id,
-      ].join(':');
-    }
-    case 'CreateFrom':
-    case 'ImmutableCapture':
-    case 'Assign':
-    case 'Alias':
-    case 'Capture':
-    case 'MaybeAlias': {
-      return [
-        effect.kind,
-        effect.from.identifier.id,
-        effect.into.identifier.id,
-      ].join(':');
-    }
-    case 'Create': {
-      return [
-        effect.kind,
-        effect.into.identifier.id,
-        effect.value,
-        effect.reason,
-      ].join(':');
-    }
-    case 'Freeze': {
-      return [effect.kind, effect.value.identifier.id, effect.reason].join(':');
-    }
-    case 'Impure':
-    case 'Render': {
-      return [effect.kind, effect.place.identifier.id].join(':');
-    }
-    case 'MutateFrozen':
-    case 'MutateGlobal': {
-      return [
-        effect.kind,
-        effect.place.identifier.id,
-        effect.error.severity,
-        effect.error.category,
-        effect.error.description,
-        printSourceLocation(effect.error.primaryLocation() ?? GeneratedSource),
-      ].join(':');
-    }
-    case 'Mutate':
-    case 'MutateConditionally':
-    case 'MutateTransitive':
-    case 'MutateTransitiveConditionally': {
-      return [effect.kind, effect.value.identifier.id].join(':');
-    }
-    case 'CreateFunction': {
-      return [
-        effect.kind,
-        effect.into.identifier.id,
-        // return places are a unique way to identify functions themselves
-        effect.function.loweredFunc.func.returns.identifier.id,
-        effect.captures.map(p => p.identifier.id).join(','),
-      ].join(':');
-    }
-  }
-}
-
-export type AliasingSignature = {
-  receiver: IdentifierId;
-  params: Array<IdentifierId>;
-  rest: IdentifierId | null;
-  returns: IdentifierId;
-  effects: Array<AliasingEffect>;
-  temporaries: Array<Place>;
-};

compiler/packages/babel-plugin-react-compiler/src/Inference/AnalyseFunctions.ts

@@ -10,7 +10,6 @@ import {
   Effect,
   HIRFunction,
   Identifier,
-  IdentifierId,
   LoweredFunction,
   isRefOrRefValue,
   makeInstructionId,
@@ -20,9 +19,6 @@ import {inferReactiveScopeVariables} from '../ReactiveScopes';
 import {rewriteInstructionKindsBasedOnReassignment} from '../SSA';
 import {inferMutableRanges} from './InferMutableRanges';
 import inferReferenceEffects from './InferReferenceEffects';
-import {assertExhaustive} from '../Utils/utils';
-import {inferMutationAliasingEffects} from './InferMutationAliasingEffects';
-import {inferMutationAliasingRanges} from './InferMutationAliasingRanges';
 
 export default function analyseFunctions(func: HIRFunction): void {
   for (const [_, block] of func.body.blocks) {
@@ -30,27 +26,15 @@ export default function analyseFunctions(func: HIRFunction): void {
       switch (instr.value.kind) {
         case 'ObjectMethod':
         case 'FunctionExpression': {
-          if (!func.env.config.enableNewMutationAliasingModel) {
-            lower(instr.value.loweredFunc.func);
-            infer(instr.value.loweredFunc);
-          } else {
-            lowerWithMutationAliasing(instr.value.loweredFunc.func);
-          }
+          lower(instr.value.loweredFunc.func);
+          infer(instr.value.loweredFunc);
 
           /**
            * Reset mutable range for outer inferReferenceEffects
            */
           for (const operand of instr.value.loweredFunc.func.context) {
-            /**
-             * NOTE: inferReactiveScopeVariables makes identifiers in the scope
-             * point to the *same* mutableRange instance. Resetting start/end
-             * here is insufficient, because a later mutation of the range
-             * for any one identifier could affect the range for other identifiers.
-             */
-            operand.identifier.mutableRange = {
-              start: makeInstructionId(0),
-              end: makeInstructionId(0),
-            };
+            operand.identifier.mutableRange.start = makeInstructionId(0);
+            operand.identifier.mutableRange.end = makeInstructionId(0);
             operand.identifier.scope = null;
           }
           break;
@@ -60,87 +44,6 @@ export default function analyseFunctions(func: HIRFunction): void {
   }
 }
 
-function lowerWithMutationAliasing(fn: HIRFunction): void {
-  /**
-   * Phase 1: similar to lower(), but using the new mutation/aliasing inference
-   */
-  analyseFunctions(fn);
-  inferMutationAliasingEffects(fn, {isFunctionExpression: true});
-  deadCodeElimination(fn);
-  const functionEffects = inferMutationAliasingRanges(fn, {
-    isFunctionExpression: true,
-  }).unwrap();
-  rewriteInstructionKindsBasedOnReassignment(fn);
-  inferReactiveScopeVariables(fn);
-  fn.aliasingEffects = functionEffects;
-
-  /**
-   * Phase 2: populate the Effect of each context variable to use in inferring
-   * the outer function. For example, InferMutationAliasingEffects uses context variable
-   * effects to decide if the function may be mutable or not.
-   */
-  const capturedOrMutated = new Set<IdentifierId>();
-  for (const effect of functionEffects) {
-    switch (effect.kind) {
-      case 'Assign':
-      case 'Alias':
-      case 'Capture':
-      case 'CreateFrom':
-      case 'MaybeAlias': {
-        capturedOrMutated.add(effect.from.identifier.id);
-        break;
-      }
-      case 'Apply': {
-        CompilerError.invariant(false, {
-          reason: `[AnalyzeFunctions] Expected Apply effects to be replaced with more precise effects`,
-          loc: effect.function.loc,
-        });
-      }
-      case 'Mutate':
-      case 'MutateConditionally':
-      case 'MutateTransitive':
-      case 'MutateTransitiveConditionally': {
-        capturedOrMutated.add(effect.value.identifier.id);
-        break;
-      }
-      case 'Impure':
-      case 'Render':
-      case 'MutateFrozen':
-      case 'MutateGlobal':
-      case 'CreateFunction':
-      case 'Create':
-      case 'Freeze':
-      case 'ImmutableCapture': {
-        // no-op
-        break;
-      }
-      default: {
-        assertExhaustive(
-          effect,
-          `Unexpected effect kind ${(effect as any).kind}`,
-        );
-      }
-    }
-  }
-
-  for (const operand of fn.context) {
-    if (
-      capturedOrMutated.has(operand.identifier.id) ||
-      operand.effect === Effect.Capture
-    ) {
-      operand.effect = Effect.Capture;
-    } else {
-      operand.effect = Effect.Read;
-    }
-  }
-
-  fn.env.logger?.debugLogIRs?.({
-    kind: 'hir',
-    name: 'AnalyseFunction (inner)',
-    value: fn,
-  });
-}
-
 function lower(func: HIRFunction): void {
   analyseFunctions(func);
   inferReferenceEffects(func, {isFunctionExpression: true});

compiler/packages/babel-plugin-react-compiler/src/Inference/DropManualMemoization.ts

@@ -5,12 +5,7 @@
  * LICENSE file in the root directory of this source tree.
  */
 
-import {
-  CompilerDiagnostic,
-  CompilerError,
-  ErrorSeverity,
-  SourceLocation,
-} from '..';
+import {CompilerError, SourceLocation} from '..';
 import {
   CallExpression,
   Effect,
@@ -35,7 +30,6 @@ import {
   makeInstructionId,
 } from '../HIR';
 import {createTemporaryPlace, markInstructionIds} from '../HIR/HIRBuilder';
-import {Result} from '../Utils/Result';
 
 type ManualMemoCallee = {
   kind: 'useMemo' | 'useCallback';
@@ -203,7 +197,6 @@ function makeManualMemoizationMarkers(
         deps: depsList,
         loc: fnExpr.loc,
       },
-      effects: null,
       loc: fnExpr.loc,
     },
     {
@@ -215,7 +208,6 @@ function makeManualMemoizationMarkers(
         decl: {...memoDecl},
         loc: fnExpr.loc,
       },
-      effects: null,
       loc: fnExpr.loc,
     },
   ];
@@ -289,43 +281,26 @@ function extractManualMemoizationArgs(
   instr: TInstruction<CallExpression> | TInstruction<MethodCall>,
   kind: 'useCallback' | 'useMemo',
   sidemap: IdentifierSidemap,
-  errors: CompilerError,
 ): {
-  fnPlace: Place | null;
+  fnPlace: Place;
   depsList: Array<ManualMemoDependency> | null;
 } {
   const [fnPlace, depsListPlace] = instr.value.args as Array<
     Place | SpreadPattern | undefined
   >;
   if (fnPlace == null) {
-    errors.pushDiagnostic(
-      CompilerDiagnostic.create({
-        severity: ErrorSeverity.InvalidReact,
-        category: `Expected a callback function to be passed to ${kind}`,
-        description: `Expected a callback function to be passed to ${kind}`,
-        suggestions: null,
-      }).withDetail({
-        kind: 'error',
-        loc: instr.value.loc,
-        message: `Expected a callback function to be passed to ${kind}`,
-      }),
-    );
-    return {fnPlace: null, depsList: null};
+    CompilerError.throwInvalidReact({
+      reason: `Expected a callback function to be passed to ${kind}`,
+      loc: instr.value.loc,
+      suggestions: null,
+    });
   }
   if (fnPlace.kind === 'Spread' || depsListPlace?.kind === 'Spread') {
-    errors.pushDiagnostic(
-      CompilerDiagnostic.create({
-        severity: ErrorSeverity.InvalidReact,
-        category: `Unexpected spread argument to ${kind}`,
-        description: `Unexpected spread argument to ${kind}`,
-        suggestions: null,
-      }).withDetail({
-        kind: 'error',
-        loc: instr.value.loc,
-        message: `Unexpected spread argument to ${kind}`,
-      }),
-    );
-    return {fnPlace: null, depsList: null};
+    CompilerError.throwInvalidReact({
+      reason: `Unexpected spread argument to ${kind}`,
+      loc: instr.value.loc,
+      suggestions: null,
+    });
   }
   let depsList: Array<ManualMemoDependency> | null = null;
   if (depsListPlace != null) {
@@ -333,40 +308,23 @@ function extractManualMemoizationArgs(
       depsListPlace.identifier.id,
     );
     if (maybeDepsList == null) {
-      errors.pushDiagnostic(
-        CompilerDiagnostic.create({
-          severity: ErrorSeverity.InvalidReact,
-          category: `Expected the dependency list for ${kind} to be an array literal`,
-          description: `Expected the dependency list for ${kind} to be an array literal`,
-          suggestions: null,
-        }).withDetail({
-          kind: 'error',
-          loc: depsListPlace.loc,
-          message: `Expected the dependency list for ${kind} to be an array literal`,
-        }),
-      );
-      return {fnPlace, depsList: null};
+      CompilerError.throwInvalidReact({
+        reason: `Expected the dependency list for ${kind} to be an array literal`,
+        suggestions: null,
+        loc: depsListPlace.loc,
+      });
     }
-    depsList = [];
-    for (const dep of maybeDepsList) {
+    depsList = maybeDepsList.map(dep => {
       const maybeDep = sidemap.maybeDeps.get(dep.identifier.id);
       if (maybeDep == null) {
-        errors.pushDiagnostic(
-          CompilerDiagnostic.create({
-            severity: ErrorSeverity.InvalidReact,
-            category: `Expected the dependency list to be an array of simple expressions (e.g. \`x\`, \`x.y.z\`, \`x?.y?.z\`)`,
-            description: `Expected the dependency list to be an array of simple expressions (e.g. \`x\`, \`x.y.z\`, \`x?.y?.z\`)`,
-            suggestions: null,
-          }).withDetail({
-            kind: 'error',
-            loc: dep.loc,
-            message: `Expected the dependency list to be an array of simple expressions (e.g. \`x\`, \`x.y.z\`, \`x?.y?.z\`)`,
-          }),
-        );
-      } else {
-        depsList.push(maybeDep);
+        CompilerError.throwInvalidReact({
+          reason: `Expected the dependency list to be an array of simple expressions (e.g. \`x\`, \`x.y.z\`, \`x?.y?.z\`)`,
+          suggestions: null,
+          loc: dep.loc,
+        });
       }
-    }
+      return maybeDep;
+    });
   }
   return {
     fnPlace,
@@ -381,14 +339,8 @@ function extractManualMemoizationArgs(
  * rely on type inference to find useMemo/useCallback invocations, and instead does basic tracking
  * of globals and property loads to find both direct calls as well as usage via the React namespace,
  * eg `React.useMemo()`.
- *
- * This pass also validates that useMemo callbacks return a value (not void), ensuring that useMemo
- * is only used for memoizing values and not for running arbitrary side effects.
  */
-export function dropManualMemoization(
-  func: HIRFunction,
-): Result<void, CompilerError> {
-  const errors = new CompilerError();
+export function dropManualMemoization(func: HIRFunction): void {
   const isValidationEnabled =
     func.env.config.validatePreserveExistingMemoizationGuarantees ||
     func.env.config.validateNoSetStateInRender ||
@@ -435,47 +387,7 @@ export function dropManualMemoization(
             instr as TInstruction<CallExpression> | TInstruction<MethodCall>,
             manualMemo.kind,
             sidemap,
-            errors,
           );
-
-          if (fnPlace == null) {
-            continue;
-          }
-
-          /**
-           * Bailout on void return useMemos. This is an anti-pattern where code might be using
-           * useMemo like useEffect: running arbirtary side-effects synced to changes in specific
-           * values.
-           */
-          if (
-            func.env.config.validateNoVoidUseMemo &&
-            manualMemo.kind === 'useMemo'
-          ) {
-            const funcToCheck = sidemap.functions.get(
-              fnPlace.identifier.id,
-            )?.value;
-            if (funcToCheck !== undefined && funcToCheck.loweredFunc.func) {
-              if (!hasNonVoidReturn(funcToCheck.loweredFunc.func)) {
-                errors.pushDiagnostic(
-                  CompilerDiagnostic.create({
-                    severity: ErrorSeverity.InvalidReact,
-                    category: 'useMemo() callbacks must return a value',
-                    description: `This ${
-                      manualMemo.loadInstr.value.kind === 'PropertyLoad'
-                        ? 'React.useMemo'
-                        : 'useMemo'
-                    } callback doesn't return a value. useMemo is for computing and caching values, not for arbitrary side effects.`,
-                    suggestions: null,
-                  }).withDetail({
-                    kind: 'error',
-                    loc: instr.value.loc,
-                    message: 'useMemo() callbacks must return a value',
-                  }),
-                );
-              }
-            }
-          }
-
           instr.value = getManualMemoizationReplacement(
             fnPlace,
             instr.value.loc,
@@ -496,19 +408,11 @@ export function dropManualMemoization(
              * is rare and likely sketchy.
              */
             if (!sidemap.functions.has(fnPlace.identifier.id)) {
-              errors.pushDiagnostic(
-                CompilerDiagnostic.create({
-                  severity: ErrorSeverity.InvalidReact,
-                  category: `Expected the first argument to be an inline function expression`,
-                  description: `Expected the first argument to be an inline function expression`,
-                  suggestions: [],
-                }).withDetail({
-                  kind: 'error',
-                  loc: fnPlace.loc,
-                  message: `Expected the first argument to be an inline function expression`,
-                }),
-              );
-              continue;
+              CompilerError.throwInvalidReact({
+                reason: `Expected the first argument to be an inline function expression`,
+                suggestions: [],
+                loc: fnPlace.loc,
+              });
             }
             const memoDecl: Place =
               manualMemo.kind === 'useMemo'
@@ -580,8 +484,6 @@ export function dropManualMemoization(
       markInstructionIds(func.body);
     }
   }
-
-  return errors.asResult();
 }
 
 function findOptionalPlaces(fn: HIRFunction): Set<IdentifierId> {
@@ -626,17 +528,3 @@ function findOptionalPlaces(fn: HIRFunction): Set<IdentifierId> {
   }
   return optionals;
 }
-
-function hasNonVoidReturn(func: HIRFunction): boolean {
-  for (const [, block] of func.body.blocks) {
-    if (block.terminal.kind === 'return') {
-      if (
-        block.terminal.returnVariant === 'Explicit' ||
-        block.terminal.returnVariant === 'Implicit'
-      ) {
-        return true;
-      }
-    }
-  }
-  return false;
-}

compiler/packages/babel-plugin-react-compiler/src/Inference/InerAliasForUncalledFunctions.ts

@@ -1,134 +0,0 @@
-/**
- * Copyright (c) Meta Platforms, Inc. and affiliates.
- *
- * This source code is licensed under the MIT license found in the
- * LICENSE file in the root directory of this source tree.
- */
-
-import {
-  Effect,
-  HIRFunction,
-  Identifier,
-  isMutableEffect,
-  isRefOrRefLikeMutableType,
-  makeInstructionId,
-} from '../HIR/HIR';
-import {eachInstructionValueOperand} from '../HIR/visitors';
-import {isMutable} from '../ReactiveScopes/InferReactiveScopeVariables';
-import DisjointSet from '../Utils/DisjointSet';
-
-/**
- * If a function captures a mutable value but never gets called, we don't infer a
- * mutable range for that function. This means that we also don't alias the function
- * with its mutable captures.
- *
- * This case is tricky, because we don't generally know for sure what is a mutation
- * and what may just be a normal function call. For example:
- *
- * ```
- * hook useFoo() {
- *   const x = makeObject();
- *   return () => {
- *     return readObject(x); // could be a mutation!
- *   }
- * }
- * ```
- *
- * If we pessimistically assume that all such cases are mutations, we'd have to group
- * lots of memo scopes together unnecessarily. However, if there is definitely a mutation:
- *
- * ```
- * hook useFoo(createEntryForKey) {
- *   const cache = new WeakMap();
- *   return (key) => {
- *     let entry = cache.get(key);
- *     if (entry == null) {
- *       entry = createEntryForKey(key);
- *       cache.set(key, entry); // known mutation!
- *     }
- *     return entry;
- *   }
- * }
- * ```
- *
- * Then we have to ensure that the function and its mutable captures alias together and
- * end up in the same scope. However, aliasing together isn't enough if the function
- * and operands all have empty mutable ranges (end = start + 1).
- *
- * This pass finds function expressions and object methods that have an empty mutable range
- * and known-mutable operands which also don't have a mutable range, and ensures that the
- * function and those operands are aliased together *and* that their ranges are updated to
- * end after the function expression. This is sufficient to ensure that a reactive scope is
- * created for the alias set.
- */
-export function inferAliasForUncalledFunctions(
-  fn: HIRFunction,
-  aliases: DisjointSet<Identifier>,
-): void {
-  for (const block of fn.body.blocks.values()) {
-    instrs: for (const instr of block.instructions) {
-      const {lvalue, value} = instr;
-      if (
-        value.kind !== 'ObjectMethod' &&
-        value.kind !== 'FunctionExpression'
-      ) {
-        continue;
-      }
-      /*
-       * If the function is known to be mutated, we will have
-       * already aliased any mutable operands with it
-       */
-      const range = lvalue.identifier.mutableRange;
-      if (range.end > range.start + 1) {
-        continue;
-      }
-      /*
-       * If the function already has operands with an active mutable range,
-       * then we don't need to do anything — the function will have already
-       * been visited and included in some mutable alias set. This case can
-       * also occur due to visiting the same function in an earlier iteration
-       * of the outer fixpoint loop.
-       */
-      for (const operand of eachInstructionValueOperand(value)) {
-        if (isMutable(instr, operand)) {
-          continue instrs;
-        }
-      }
-      const operands: Set<Identifier> = new Set();
-      for (const effect of value.loweredFunc.func.effects ?? []) {
-        if (effect.kind !== 'ContextMutation') {
-          continue;
-        }
-        /*
-         * We're looking for known-mutations only, so we look at the effects
-         * rather than function context
-         */
-        if (effect.effect === Effect.Store || effect.effect === Effect.Mutate) {
-          for (const operand of effect.places) {
-            /*
-             * It's possible that function effect analysis thinks there was a context mutation,
-             * but then InferReferenceEffects figures out some operands are globals and therefore
-             * creates a non-mutable effect for those operands.
-             * We should change InferReferenceEffects to swap the ContextMutation for a global
-             * mutation in that case, but for now we just filter them out here
-             */
-            if (
-              isMutableEffect(operand.effect, operand.loc) &&
-              !isRefOrRefLikeMutableType(operand.identifier.type)
-            ) {
-              operands.add(operand.identifier);
-            }
-          }
-        }
-      }
-      if (operands.size !== 0) {
-        operands.add(lvalue.identifier);
-        aliases.union([...operands]);
-        // Update mutable ranges, if the ranges are empty then a reactive scope isn't created
-        for (const operand of operands) {
-          operand.mutableRange.end = makeInstructionId(instr.id + 1);
-        }
-      }
-    }
-  }
-}

compiler/packages/babel-plugin-react-compiler/src/Inference/InferEffectDependencies.ts

@@ -1,15 +1,8 @@
-/**
- * Copyright (c) Meta Platforms, Inc. and affiliates.
- *
- * This source code is licensed under the MIT license found in the
- * LICENSE file in the root directory of this source tree.
- */
-
-import * as t from '@babel/types';
 import {CompilerError, SourceLocation} from '..';
 import {
   ArrayExpression,
   Effect,
+  Environment,
   FunctionExpression,
   GeneratedSource,
   HIRFunction,
@@ -21,50 +14,25 @@ import {
   ScopeId,
   ReactiveScopeDependency,
   Place,
-  ReactiveScope,
   ReactiveScopeDependencies,
-  Terminal,
   isUseRefType,
   isSetStateType,
-  isFireFunctionType,
-  makeScopeId,
-  HIR,
-  BasicBlock,
-  BlockId,
-  isEffectEventFunctionType,
 } from '../HIR';
-import {collectHoistablePropertyLoadsInInnerFn} from '../HIR/CollectHoistablePropertyLoads';
-import {collectOptionalChainSidemap} from '../HIR/CollectOptionalChainDependencies';
-import {ReactiveScopeDependencyTreeHIR} from '../HIR/DeriveMinimalDependenciesHIR';
 import {DEFAULT_EXPORT} from '../HIR/Environment';
 import {
   createTemporaryPlace,
   fixScopeAndIdentifierRanges,
   markInstructionIds,
-  markPredecessors,
-  reversePostorderBlocks,
 } from '../HIR/HIRBuilder';
-import {
-  collectTemporariesSidemap,
-  DependencyCollectionContext,
-  handleInstruction,
-} from '../HIR/PropagateScopeDependenciesHIR';
-import {buildDependencyInstructions} from '../HIR/ScopeDependencyUtils';
-import {
-  eachInstructionOperand,
-  eachTerminalOperand,
-  terminalFallthrough,
-} from '../HIR/visitors';
-import {empty} from '../Utils/Stack';
+import {eachInstructionOperand, eachTerminalOperand} from '../HIR/visitors';
 import {getOrInsertWith} from '../Utils/utils';
-import {deadCodeElimination} from '../Optimization';
-import {BuiltInAutodepsId} from '../HIR/ObjectShape';
 
 /**
  * Infers reactive dependencies captured by useEffect lambdas and adds them as
  * a second argument to the useEffect call if no dependency array is provided.
  */
 export function inferEffectDependencies(fn: HIRFunction): void {
+  let hasRewrite = false;
   const fnExpressions = new Map<
     IdentifierId,
     TInstruction<FunctionExpression>
@@ -79,13 +47,16 @@ export function inferEffectDependencies(fn: HIRFunction): void {
     );
     moduleTargets.set(
       effectTarget.function.importSpecifierName,
-      effectTarget.autodepsIndex,
+      effectTarget.numRequiredArgs,
     );
   }
   const autodepFnLoads = new Map<IdentifierId, number>();
   const autodepModuleLoads = new Map<IdentifierId, Map<string, number>>();
 
-  const scopeInfos = new Map<ScopeId, ReactiveScopeDependencies>();
+  const scopeInfos = new Map<
+    ScopeId,
+    {pruned: boolean; deps: ReactiveScopeDependencies; hasSingleInstr: boolean}
+  >();
 
   const loadGlobals = new Set<IdentifierId>();
 
@@ -97,23 +68,23 @@ export function inferEffectDependencies(fn: HIRFunction): void {
    * reactive(Identifier i) = Union_{reference of i}(reactive(reference))
    */
   const reactiveIds = inferReactiveIdentifiers(fn);
-  const rewriteBlocks: Array<BasicBlock> = [];
 
   for (const [, block] of fn.body.blocks) {
-    if (block.terminal.kind === 'scope') {
+    if (
+      block.terminal.kind === 'scope' ||
+      block.terminal.kind === 'pruned-scope'
+    ) {
       const scopeBlock = fn.body.blocks.get(block.terminal.block)!;
-      if (
-        scopeBlock.instructions.length === 1 &&
-        scopeBlock.terminal.kind === 'goto' &&
-        scopeBlock.terminal.block === block.terminal.fallthrough
-      ) {
-        scopeInfos.set(
-          block.terminal.scope.id,
-          block.terminal.scope.dependencies,
-        );
-      }
+      scopeInfos.set(block.terminal.scope.id, {
+        pruned: block.terminal.kind === 'pruned-scope',
+        deps: block.terminal.scope.dependencies,
+        hasSingleInstr:
+          scopeBlock.instructions.length === 1 &&
+          scopeBlock.terminal.kind === 'goto' &&
+          scopeBlock.terminal.block === block.terminal.fallthrough,
+      });
     }
-    const rewriteInstrs: Array<SpliceInfo> = [];
+    const rewriteInstrs = new Map<InstructionId, Array<Instruction>>();
     for (const instr of block.instructions) {
       const {value, lvalue} = instr;
       if (value.kind === 'FunctionExpression') {
@@ -137,6 +108,7 @@ export function inferEffectDependencies(fn: HIRFunction): void {
         }
       } else if (value.kind === 'LoadGlobal') {
         loadGlobals.add(lvalue.identifier.id);
+
         /*
          * TODO: Handle properties on default exports, like
          * import React from 'react';
@@ -170,26 +142,13 @@ export function inferEffectDependencies(fn: HIRFunction): void {
       ) {
         const callee =
           value.kind === 'CallExpression' ? value.callee : value.property;
-
-        const autodepsArgIndex = value.args.findIndex(
-          arg =>
-            arg.kind === 'Identifier' &&
-            arg.identifier.type.kind === 'Object' &&
-            arg.identifier.type.shapeId === BuiltInAutodepsId,
-        );
-        const autodepsArgExpectedIndex = autodepFnLoads.get(
-          callee.identifier.id,
-        );
-
         if (
-          value.args.length > 0 &&
-          autodepsArgExpectedIndex != null &&
-          autodepsArgIndex === autodepsArgExpectedIndex &&
-          autodepFnLoads.has(callee.identifier.id) &&
+          value.args.length === autodepFnLoads.get(callee.identifier.id) &&
           value.args[0].kind === 'Identifier'
         ) {
           // We have a useEffect call with no deps array, so we need to infer the deps
           const effectDeps: Array<Place> = [];
+          const newInstructions: Array<Instruction> = [];
           const deps: ArrayExpression = {
             kind: 'ArrayExpression',
             elements: effectDeps,
@@ -205,12 +164,22 @@ export function inferEffectDependencies(fn: HIRFunction): void {
               fnExpr.lvalue.identifier.scope != null
                 ? scopeInfos.get(fnExpr.lvalue.identifier.scope.id)
                 : null;
-            let minimalDeps: Set<ReactiveScopeDependency>;
-            if (scopeInfo != null) {
-              minimalDeps = new Set(scopeInfo);
-            } else {
-              minimalDeps = inferMinimalDependencies(fnExpr);
+            CompilerError.invariant(scopeInfo != null, {
+              reason: 'Expected function expression scope to exist',
+              loc: value.loc,
+            });
+            if (scopeInfo.pruned || !scopeInfo.hasSingleInstr) {
+              /**
+               * TODO: retry pipeline that ensures effect function expressions
+               * are placed into their own scope
+               */
+              CompilerError.throwTodo({
+                reason:
+                  '[InferEffectDependencies] Expected effect function to have non-pruned scope and its scope to have exactly one instruction',
+                loc: fnExpr.loc,
+              });
             }
+
             /**
              * Step 1: push dependencies to the effect deps array
              *
@@ -218,275 +187,128 @@ export function inferEffectDependencies(fn: HIRFunction): void {
              * the `infer-effect-deps/pruned-nonreactive-obj` fixture for an
              * explanation.
              */
-
-            const usedDeps = [];
-            for (const maybeDep of minimalDeps) {
+            for (const dep of scopeInfo.deps) {
               if (
-                ((isUseRefType(maybeDep.identifier) ||
-                  isSetStateType(maybeDep.identifier)) &&
-                  !reactiveIds.has(maybeDep.identifier.id)) ||
-                isFireFunctionType(maybeDep.identifier) ||
-                isEffectEventFunctionType(maybeDep.identifier)
+                (isUseRefType(dep.identifier) ||
+                  isSetStateType(dep.identifier)) &&
+                !reactiveIds.has(dep.identifier.id)
               ) {
                 // exclude non-reactive hook results, which will never be in a memo block
                 continue;
               }
 
-              const dep = truncateDepAtCurrent(maybeDep);
-              const {place, value, exitBlockId} = buildDependencyInstructions(
+              const {place, instructions} = writeDependencyToInstructions(
                 dep,
+                reactiveIds.has(dep.identifier.id),
                 fn.env,
+                fnExpr.loc,
               );
-              rewriteInstrs.push({
-                kind: 'block',
-                location: instr.id,
-                value,
-                exitBlockId: exitBlockId,
-              });
+              newInstructions.push(...instructions);
               effectDeps.push(place);
-              usedDeps.push(dep);
             }
 
-            // For LSP autodeps feature.
-            const decorations: Array<t.SourceLocation> = [];
-            for (const loc of collectDepUsages(usedDeps, fnExpr.value)) {
-              if (typeof loc === 'symbol') {
-                continue;
-              }
-              decorations.push(loc);
-            }
-            if (typeof value.loc !== 'symbol') {
-              fn.env.logger?.logEvent(fn.env.filename, {
-                kind: 'AutoDepsDecorations',
-                fnLoc: value.loc,
-                decorations,
-              });
-            }
+            newInstructions.push({
+              id: makeInstructionId(0),
+              loc: GeneratedSource,
+              lvalue: {...depsPlace, effect: Effect.Mutate},
+              value: deps,
+            });
 
             // Step 2: push the inferred deps array as an argument of the useEffect
-            rewriteInstrs.push({
-              kind: 'instr',
-              location: instr.id,
-              value: {
-                id: makeInstructionId(0),
-                loc: GeneratedSource,
-                lvalue: {...depsPlace, effect: Effect.Mutate},
-                value: deps,
-                effects: null,
-              },
-            });
-            value.args[autodepsArgIndex] = {
-              ...depsPlace,
-              effect: Effect.Freeze,
-            };
-            fn.env.inferredEffectLocations.add(callee.loc);
+            value.args.push({...depsPlace, effect: Effect.Freeze});
+            rewriteInstrs.set(instr.id, newInstructions);
           } else if (loadGlobals.has(value.args[0].identifier.id)) {
             // Global functions have no reactive dependencies, so we can insert an empty array
-            rewriteInstrs.push({
-              kind: 'instr',
-              location: instr.id,
-              value: {
-                id: makeInstructionId(0),
-                loc: GeneratedSource,
-                lvalue: {...depsPlace, effect: Effect.Mutate},
-                value: deps,
-                effects: null,
-              },
-            });
-            value.args[autodepsArgIndex] = {
-              ...depsPlace,
-              effect: Effect.Freeze,
-            };
-            fn.env.inferredEffectLocations.add(callee.loc);
-          }
-        } else if (
-          value.args.length >= 2 &&
-          value.args.length - 1 === autodepFnLoads.get(callee.identifier.id) &&
-          value.args[0] != null &&
-          value.args[0].kind === 'Identifier'
-        ) {
-          const penultimateArg = value.args[value.args.length - 2];
-          const depArrayArg = value.args[value.args.length - 1];
-          if (
-            depArrayArg.kind !== 'Spread' &&
-            penultimateArg.kind !== 'Spread' &&
-            typeof depArrayArg.loc !== 'symbol' &&
-            typeof penultimateArg.loc !== 'symbol' &&
-            typeof value.loc !== 'symbol'
-          ) {
-            fn.env.logger?.logEvent(fn.env.filename, {
-              kind: 'AutoDepsEligible',
-              fnLoc: value.loc,
-              depArrayLoc: {
-                ...depArrayArg.loc,
-                start: penultimateArg.loc.end,
-                end: depArrayArg.loc.end,
-              },
+            newInstructions.push({
+              id: makeInstructionId(0),
+              loc: GeneratedSource,
+              lvalue: {...depsPlace, effect: Effect.Mutate},
+              value: deps,
             });
+            value.args.push({...depsPlace, effect: Effect.Freeze});
+            rewriteInstrs.set(instr.id, newInstructions);
           }
         }
       }
     }
-    rewriteSplices(block, rewriteInstrs, rewriteBlocks);
-  }
-
-  if (rewriteBlocks.length > 0) {
-    for (const block of rewriteBlocks) {
-      fn.body.blocks.set(block.id, block);
+    if (rewriteInstrs.size > 0) {
+      hasRewrite = true;
+      const newInstrs = [];
+      for (const instr of block.instructions) {
+        const newInstr = rewriteInstrs.get(instr.id);
+        if (newInstr != null) {
+          newInstrs.push(...newInstr, instr);
+        } else {
+          newInstrs.push(instr);
+        }
+      }
+      block.instructions = newInstrs;
     }
-
-    /**
-     * Fixup the HIR to restore RPO, ensure correct predecessors, and renumber
-     * instructions.
-     */
-    reversePostorderBlocks(fn.body);
-    markPredecessors(fn.body);
+  }
+  if (hasRewrite) {
     // Renumber instructions and fix scope ranges
     markInstructionIds(fn.body);
     fixScopeAndIdentifierRanges(fn.body);
-    deadCodeElimination(fn);
-
-    fn.env.hasInferredEffect = true;
   }
 }
 
-function truncateDepAtCurrent(
+function writeDependencyToInstructions(
   dep: ReactiveScopeDependency,
-): ReactiveScopeDependency {
-  const idx = dep.path.findIndex(path => path.property === 'current');
-  if (idx === -1) {
-    return dep;
-  } else {
-    return {...dep, path: dep.path.slice(0, idx)};
-  }
-}
-
-type SpliceInfo =
-  | {kind: 'instr'; location: InstructionId; value: Instruction}
-  | {
-      kind: 'block';
-      location: InstructionId;
-      value: HIR;
-      exitBlockId: BlockId;
-    };
-
-function rewriteSplices(
-  originalBlock: BasicBlock,
-  splices: Array<SpliceInfo>,
-  rewriteBlocks: Array<BasicBlock>,
-): void {
-  if (splices.length === 0) {
-    return;
-  }
-  /**
-   * Splice instructions or value blocks into the original block.
-   * --- original block ---
-   * bb_original
-   *   instr1
-   *   ...
-   *   instr2 <-- splice location
-   *   instr3
-   *   ...
-   *   <original terminal>
-   *
-   * If there is more than one block in the splice, this means that we're
-   * splicing in a set of value-blocks of the following structure:
-   * --- blocks we're splicing in ---
-   * bb_entry:
-   *   instrEntry
-   *   ...
-   *   <splice terminal> fallthrough=bb_exit
-   *
-   * bb1(value):
-   *   ...
-   *
-   * bb_exit:
-   *   instrExit
-   *   ...
-   *   <synthetic terminal>
-   *
-   *
-   * --- rewritten blocks ---
-   * bb_original
-   *   instr1
-   *   ... (original instructions)
-   *   instr2
-   *   instrEntry
-   *   ... (spliced instructions)
-   *   <splice terminal> fallthrough=bb_exit
-   *
-   * bb1(value):
-   *   ...
-   *
-   * bb_exit:
-   *   instrExit
-   *   ... (spliced instructions)
-   *   instr3
-   *   ... (original instructions)
-   *   <original terminal>
-   */
-  const originalInstrs = originalBlock.instructions;
-  let currBlock: BasicBlock = {...originalBlock, instructions: []};
-  rewriteBlocks.push(currBlock);
-
-  let cursor = 0;
-
-  for (const rewrite of splices) {
-    while (originalInstrs[cursor].id < rewrite.location) {
-      CompilerError.invariant(
-        originalInstrs[cursor].id < originalInstrs[cursor + 1].id,
-        {
-          reason:
-            '[InferEffectDependencies] Internal invariant broken: expected block instructions to be sorted',
-          loc: originalInstrs[cursor].loc,
-        },
-      );
-      currBlock.instructions.push(originalInstrs[cursor]);
-      cursor++;
+  reactive: boolean,
+  env: Environment,
+  loc: SourceLocation,
+): {place: Place; instructions: Array<Instruction>} {
+  const instructions: Array<Instruction> = [];
+  let currValue = createTemporaryPlace(env, GeneratedSource);
+  currValue.reactive = reactive;
+  instructions.push({
+    id: makeInstructionId(0),
+    loc: GeneratedSource,
+    lvalue: {...currValue, effect: Effect.Mutate},
+    value: {
+      kind: 'LoadLocal',
+      place: {
+        kind: 'Identifier',
+        identifier: dep.identifier,
+        effect: Effect.Capture,
+        reactive,
+        loc: loc,
+      },
+      loc: loc,
+    },
+  });
+  for (const path of dep.path) {
+    if (path.optional) {
+      /**
+       * TODO: instead of truncating optional paths, reuse
+       * instructions from hoisted dependencies block(s)
+       */
+      break;
     }
-    CompilerError.invariant(originalInstrs[cursor].id === rewrite.location, {
-      reason:
-        '[InferEffectDependencies] Internal invariant broken: splice location not found',
-      loc: originalInstrs[cursor].loc,
+    if (path.property === 'current') {
+      /*
+       * Prune ref.current accesses. This may over-capture for non-ref values with
+       * a current property, but that's fine.
+       */
+      break;
+    }
+    const nextValue = createTemporaryPlace(env, GeneratedSource);
+    nextValue.reactive = reactive;
+    instructions.push({
+      id: makeInstructionId(0),
+      loc: GeneratedSource,
+      lvalue: {...nextValue, effect: Effect.Mutate},
+      value: {
+        kind: 'PropertyLoad',
+        object: {...currValue, effect: Effect.Capture},
+        property: path.property,
+        loc: loc,
+      },
     });
-
-    if (rewrite.kind === 'instr') {
-      currBlock.instructions.push(rewrite.value);
-    } else if (rewrite.kind === 'block') {
-      const {entry, blocks} = rewrite.value;
-      const entryBlock = blocks.get(entry)!;
-      // splice in all instructions from the entry block
-      currBlock.instructions.push(...entryBlock.instructions);
-      if (blocks.size > 1) {
-        /**
-         * We're splicing in a set of value-blocks, which means we need
-         * to push new blocks and update terminals.
-         */
-        CompilerError.invariant(
-          terminalFallthrough(entryBlock.terminal) === rewrite.exitBlockId,
-          {
-            reason:
-              '[InferEffectDependencies] Internal invariant broken: expected entry block to have a fallthrough',
-            loc: entryBlock.terminal.loc,
-          },
-        );
-        const originalTerminal = currBlock.terminal;
-        currBlock.terminal = entryBlock.terminal;
-
-        for (const [id, block] of blocks) {
-          if (id === entry) {
-            continue;
-          }
-          if (id === rewrite.exitBlockId) {
-            block.terminal = originalTerminal;
-            currBlock = block;
-          }
-          rewriteBlocks.push(block);
-        }
-      }
-    }
+    currValue = nextValue;
   }
-  currBlock.instructions.push(...originalInstrs.slice(cursor));
+  currValue.effect = Effect.Freeze;
+  return {place: currValue, instructions};
 }
 
 function inferReactiveIdentifiers(fn: HIRFunction): Set<IdentifierId> {
@@ -513,163 +335,3 @@ function inferReactiveIdentifiers(fn: HIRFunction): Set<IdentifierId> {
   }
   return reactiveIds;
 }
-
-function collectDepUsages(
-  deps: Array<ReactiveScopeDependency>,
-  fnExpr: FunctionExpression,
-): Array<SourceLocation> {
-  const identifiers: Map<IdentifierId, ReactiveScopeDependency> = new Map();
-  const loadedDeps: Set<IdentifierId> = new Set();
-  const sourceLocations = [];
-  for (const dep of deps) {
-    identifiers.set(dep.identifier.id, dep);
-  }
-
-  for (const [, block] of fnExpr.loweredFunc.func.body.blocks) {
-    for (const instr of block.instructions) {
-      if (
-        instr.value.kind === 'LoadLocal' &&
-        identifiers.has(instr.value.place.identifier.id)
-      ) {
-        loadedDeps.add(instr.lvalue.identifier.id);
-      }
-      for (const place of eachInstructionOperand(instr)) {
-        if (loadedDeps.has(place.identifier.id)) {
-          // TODO(@jbrown215): handle member exprs!!
-          sourceLocations.push(place.identifier.loc);
-        }
-      }
-    }
-  }
-
-  return sourceLocations;
-}
-
-function inferMinimalDependencies(
-  fnInstr: TInstruction<FunctionExpression>,
-): Set<ReactiveScopeDependency> {
-  const fn = fnInstr.value.loweredFunc.func;
-
-  const temporaries = collectTemporariesSidemap(fn, new Set());
-  const {
-    hoistableObjects,
-    processedInstrsInOptional,
-    temporariesReadInOptional,
-  } = collectOptionalChainSidemap(fn);
-
-  const hoistablePropertyLoads = collectHoistablePropertyLoadsInInnerFn(
-    fnInstr,
-    temporaries,
-    hoistableObjects,
-  );
-  const hoistableToFnEntry = hoistablePropertyLoads.get(fn.body.entry);
-  CompilerError.invariant(hoistableToFnEntry != null, {
-    reason:
-      '[InferEffectDependencies] Internal invariant broken: missing entry block',
-    loc: fnInstr.loc,
-  });
-
-  const dependencies = inferDependencies(
-    fnInstr,
-    new Map([...temporaries, ...temporariesReadInOptional]),
-    processedInstrsInOptional,
-  );
-
-  const tree = new ReactiveScopeDependencyTreeHIR(
-    [...hoistableToFnEntry.assumedNonNullObjects].map(o => o.fullPath),
-  );
-  for (const dep of dependencies) {
-    tree.addDependency({...dep});
-  }
-
-  return tree.deriveMinimalDependencies();
-}
-
-function inferDependencies(
-  fnInstr: TInstruction<FunctionExpression>,
-  temporaries: ReadonlyMap<IdentifierId, ReactiveScopeDependency>,
-  processedInstrsInOptional: ReadonlySet<Instruction | Terminal>,
-): Set<ReactiveScopeDependency> {
-  const fn = fnInstr.value.loweredFunc.func;
-  const context = new DependencyCollectionContext(
-    new Set(),
-    temporaries,
-    processedInstrsInOptional,
-  );
-  for (const dep of fn.context) {
-    context.declare(dep.identifier, {
-      id: makeInstructionId(0),
-      scope: empty(),
-    });
-  }
-  const placeholderScope: ReactiveScope = {
-    id: makeScopeId(0),
-    range: {
-      start: fnInstr.id,
-      end: makeInstructionId(fnInstr.id + 1),
-    },
-    dependencies: new Set(),
-    reassignments: new Set(),
-    declarations: new Map(),
-    earlyReturnValue: null,
-    merged: new Set(),
-    loc: GeneratedSource,
-  };
-  context.enterScope(placeholderScope);
-  inferDependenciesInFn(fn, context, temporaries);
-  context.exitScope(placeholderScope, false);
-  const resultUnfiltered = context.deps.get(placeholderScope);
-  CompilerError.invariant(resultUnfiltered != null, {
-    reason:
-      '[InferEffectDependencies] Internal invariant broken: missing scope dependencies',
-    loc: fn.loc,
-  });
-
-  const fnContext = new Set(fn.context.map(dep => dep.identifier.id));
-  const result = new Set<ReactiveScopeDependency>();
-  for (const dep of resultUnfiltered) {
-    if (fnContext.has(dep.identifier.id)) {
-      result.add(dep);
-    }
-  }
-
-  return result;
-}
-
-function inferDependenciesInFn(
-  fn: HIRFunction,
-  context: DependencyCollectionContext,
-  temporaries: ReadonlyMap<IdentifierId, ReactiveScopeDependency>,
-): void {
-  for (const [, block] of fn.body.blocks) {
-    // Record referenced optional chains in phis
-    for (const phi of block.phis) {
-      for (const operand of phi.operands) {
-        const maybeOptionalChain = temporaries.get(operand[1].identifier.id);
-        if (maybeOptionalChain) {
-          context.visitDependency(maybeOptionalChain);
-        }
-      }
-    }
-    for (const instr of block.instructions) {
-      if (
-        instr.value.kind === 'FunctionExpression' ||
-        instr.value.kind === 'ObjectMethod'
-      ) {
-        context.declare(instr.lvalue.identifier, {
-          id: instr.id,
-          scope: context.currentScope,
-        });
-        /**
-         * Recursively visit the inner function to extract dependencies
-         */
-        const innerFn = instr.value.loweredFunc.func;
-        context.enterInnerFn(instr as TInstruction<FunctionExpression>, () => {
-          inferDependenciesInFn(innerFn, context, temporaries);
-        });
-      } else {
-        handleInstruction(instr, context);
-      }
-    }
-  }
-}

compiler/packages/babel-plugin-react-compiler/src/Inference/InferFunctionEffects.ts

@@ -5,12 +5,7 @@
  * LICENSE file in the root directory of this source tree.
  */
 
-import {
-  CompilerError,
-  CompilerErrorDetailOptions,
-  ErrorSeverity,
-  ValueKind,
-} from '..';
+import {CompilerError, ErrorSeverity, ValueKind} from '..';
 import {
   AbstractValue,
   BasicBlock,
@@ -295,21 +290,21 @@ export function inferTerminalFunctionEffects(
   return functionEffects;
 }
 
-export function transformFunctionEffectErrors(
+export function raiseFunctionEffectErrors(
   functionEffects: Array<FunctionEffect>,
-): Array<CompilerErrorDetailOptions> {
-  return functionEffects.map(eff => {
+): void {
+  functionEffects.forEach(eff => {
     switch (eff.kind) {
       case 'ReactMutation':
       case 'GlobalMutation': {
-        return eff.error;
+        CompilerError.throw(eff.error);
       }
       case 'ContextMutation': {
-        return {
+        CompilerError.throw({
           severity: ErrorSeverity.Invariant,
           reason: `Unexpected ContextMutation in top-level function effects`,
           loc: eff.loc,
-        };
+        });
       }
       default:
         assertExhaustive(
@@ -324,28 +319,22 @@ function isEffectSafeOutsideRender(effect: FunctionEffect): boolean {
   return effect.kind === 'GlobalMutation';
 }
 
-export function getWriteErrorReason(abstractValue: AbstractValue): string {
+function getWriteErrorReason(abstractValue: AbstractValue): string {
   if (abstractValue.reason.has(ValueReason.Global)) {
-    return 'Modifying a variable defined outside a component or hook is not allowed. Consider using an effect';
+    return 'Writing to a variable defined outside a component or hook is not allowed. Consider using an effect';
   } else if (abstractValue.reason.has(ValueReason.JsxCaptured)) {
-    return 'Modifying a value used previously in JSX is not allowed. Consider moving the modification before the JSX';
+    return 'Updating a value used previously in JSX is not allowed. Consider moving the mutation before the JSX';
   } else if (abstractValue.reason.has(ValueReason.Context)) {
-    return `Modifying a value returned from 'useContext()' is not allowed.`;
+    return `Mutating a value returned from 'useContext()', which should not be mutated`;
   } else if (abstractValue.reason.has(ValueReason.KnownReturnSignature)) {
-    return 'Modifying a value returned from a function whose return value should not be mutated';
+    return 'Mutating a value returned from a function whose return value should not be mutated';
   } else if (abstractValue.reason.has(ValueReason.ReactiveFunctionArgument)) {
-    return 'Modifying component props or hook arguments is not allowed. Consider using a local variable instead';
+    return 'Mutating component props or hook arguments is not allowed. Consider using a local variable instead';
   } else if (abstractValue.reason.has(ValueReason.State)) {
-    return "Modifying a value returned from 'useState()', which should not be modified directly. Use the setter function to update instead";
+    return "Mutating a value returned from 'useState()', which should not be mutated. Use the setter function to update instead";
   } else if (abstractValue.reason.has(ValueReason.ReducerState)) {
-    return "Modifying a value returned from 'useReducer()', which should not be modified directly. Use the dispatch function to update instead";
-  } else if (abstractValue.reason.has(ValueReason.Effect)) {
-    return 'Modifying a value used previously in an effect function or as an effect dependency is not allowed. Consider moving the modification before calling useEffect()';
-  } else if (abstractValue.reason.has(ValueReason.HookCaptured)) {
-    return 'Modifying a value previously passed as an argument to a hook is not allowed. Consider moving the modification before calling the hook';
-  } else if (abstractValue.reason.has(ValueReason.HookReturn)) {
-    return 'Modifying a value returned from a hook is not allowed. Consider moving the modification into the hook where the value is constructed';
+    return "Mutating a value returned from 'useReducer()', which should not be mutated. Use the dispatch function to update instead";
   } else {
-    return 'This modifies a variable that React considers immutable';
+    return 'This mutates a variable that React considers immutable';
   }
 }

compiler/packages/babel-plugin-react-compiler/src/Inference/InferMutableLifetimes.ts

@@ -11,10 +11,7 @@ import {
   Identifier,
   InstructionId,
   InstructionKind,
-  isArrayType,
-  isMapType,
   isRefOrRefValue,
-  isSetType,
   makeInstructionId,
   Place,
 } from '../HIR/HIR';
@@ -93,17 +90,6 @@ function inferPlace(
         infer(place, instrId);
       }
       return;
-    case Effect.ConditionallyMutateIterator: {
-      const identifier = place.identifier;
-      if (
-        !isArrayType(identifier) &&
-        !isSetType(identifier) &&
-        !isMapType(identifier)
-      ) {
-        infer(place, instrId);
-      }
-      return;
-    }
     case Effect.ConditionallyMutate:
     case Effect.Mutate: {
       infer(place, instrId);
@@ -176,15 +162,9 @@ export function inferMutableLifetimes(
       if (
         instr.value.kind === 'DeclareContext' ||
         (instr.value.kind === 'StoreContext' &&
-          instr.value.lvalue.kind !== InstructionKind.Reassign &&
-          !contextVariableDeclarationInstructions.has(
-            instr.value.lvalue.place.identifier,
-          ))
+          instr.value.lvalue.kind !== InstructionKind.Reassign)
       ) {
-        /**
-         * Save declarations of context variables if they hasn't already been
-         * declared (due to hoisted declarations).
-         */
+        // Save declarations of context variables
         contextVariableDeclarationInstructions.set(
           instr.value.lvalue.place.identifier,
           instr.id,

compiler/packages/babel-plugin-react-compiler/src/Inference/InferMutableRanges.ts

@@ -6,7 +6,6 @@
  */
 
 import {HIRFunction, Identifier} from '../HIR/HIR';
-import {inferAliasForUncalledFunctions} from './InerAliasForUncalledFunctions';
 import {inferAliases} from './InferAlias';
 import {inferAliasForPhis} from './InferAliasForPhis';
 import {inferAliasForStores} from './InferAliasForStores';
@@ -77,7 +76,6 @@ export function inferMutableRanges(ir: HIRFunction): void {
   while (true) {
     inferMutableRangesForAlias(ir, aliases);
     inferAliasForPhis(ir, aliases);
-    inferAliasForUncalledFunctions(ir, aliases);
     const nextAliases = aliases.canonicalize();
     if (areEqualMaps(prevAliases, nextAliases)) {
       break;
@@ -86,7 +84,7 @@ export function inferMutableRanges(ir: HIRFunction): void {
   }
 }
 
-function areEqualMaps<T, U>(a: Map<T, U>, b: Map<T, U>): boolean {
+function areEqualMaps<T>(a: Map<T, T>, b: Map<T, T>): boolean {
   if (a.size !== b.size) {
     return false;
   }

compiler/packages/babel-plugin-react-compiler/src/Inference/InferMutationAliasingRanges.ts

@@ -1,818 +0,0 @@
-/**
- * Copyright (c) Meta Platforms, Inc. and affiliates.
- *
- * This source code is licensed under the MIT license found in the
- * LICENSE file in the root directory of this source tree.
- */
-
-import {CompilerError, SourceLocation} from '..';
-import {
-  BlockId,
-  Effect,
-  HIRFunction,
-  Identifier,
-  IdentifierId,
-  InstructionId,
-  isJsxType,
-  makeInstructionId,
-  ValueKind,
-  ValueReason,
-  Place,
-  isPrimitiveType,
-} from '../HIR/HIR';
-import {
-  eachInstructionLValue,
-  eachInstructionValueOperand,
-  eachTerminalOperand,
-} from '../HIR/visitors';
-import {assertExhaustive, getOrInsertWith} from '../Utils/utils';
-import {Err, Ok, Result} from '../Utils/Result';
-import {AliasingEffect} from './AliasingEffects';
-
-/**
- * This pass builds an abstract model of the heap and interprets the effects of the
- * given function in order to determine the following:
- * - The mutable ranges of all identifiers in the function
- * - The externally-visible effects of the function, such as mutations of params and
- *   context-vars, aliasing between params/context-vars/return-value, and impure side
- *   effects.
- * - The legacy `Effect` to store on each Place.
- *
- * This pass builds a data flow graph using the effects, tracking an abstract notion
- * of "when" each effect occurs relative to the others. It then walks each mutation
- * effect against the graph, updating the range of each node that would be reachable
- * at the "time" that the effect occurred.
- *
- * This pass also validates against invalid effects: any function that is reachable
- * by being called, or via a Render effect, is validated against mutating globals
- * or calling impure code.
- *
- * Note that this function also populates the outer function's aliasing effects with
- * any mutations that apply to its params or context variables.
- *
- * ## Example
- * A function expression such as the following:
- *
- * ```
- * (x) => { x.y = true }
- * ```
- *
- * Would populate a `Mutate x` aliasing effect on the outer function.
- *
- * ## Returned Function Effects
- *
- * The function returns (if successful) a list of externally-visible effects.
- * This is determined by simulating a conditional, transitive mutation against
- * each param, context variable, and return value in turn, and seeing which other
- * such values are affected. If they're affected, they must be captured, so we
- * record a Capture.
- *
- * The only tricky bit is the return value, which could _alias_ (or even assign)
- * one or more of the params/context-vars rather than just capturing. So we have
- * to do a bit more tracking for returns.
- */
-export function inferMutationAliasingRanges(
-  fn: HIRFunction,
-  {isFunctionExpression}: {isFunctionExpression: boolean},
-): Result<Array<AliasingEffect>, CompilerError> {
-  // The set of externally-visible effects
-  const functionEffects: Array<AliasingEffect> = [];
-
-  /**
-   * Part 1: Infer mutable ranges for values. We build an abstract model of
-   * values, the alias/capture edges between them, and the set of mutations.
-   * Edges and mutations are ordered, with mutations processed against the
-   * abstract model only after it is fully constructed by visiting all blocks
-   * _and_ connecting phis. Phis are considered ordered at the time of the
-   * phi node.
-   *
-   * This should (may?) mean that mutations are able to see the full state
-   * of the graph and mark all the appropriate identifiers as mutated at
-   * the correct point, accounting for both backward and forward edges.
-   * Ie a mutation of x accounts for both values that flowed into x,
-   * and values that x flowed into.
-   */
-  const state = new AliasingState();
-  type PendingPhiOperand = {from: Place; into: Place; index: number};
-  const pendingPhis = new Map<BlockId, Array<PendingPhiOperand>>();
-  const mutations: Array<{
-    index: number;
-    id: InstructionId;
-    transitive: boolean;
-    kind: MutationKind;
-    place: Place;
-  }> = [];
-  const renders: Array<{index: number; place: Place}> = [];
-
-  let index = 0;
-
-  const errors = new CompilerError();
-
-  for (const param of [...fn.params, ...fn.context, fn.returns]) {
-    const place = param.kind === 'Identifier' ? param : param.place;
-    state.create(place, {kind: 'Object'});
-  }
-  const seenBlocks = new Set<BlockId>();
-  for (const block of fn.body.blocks.values()) {
-    for (const phi of block.phis) {
-      state.create(phi.place, {kind: 'Phi'});
-      for (const [pred, operand] of phi.operands) {
-        if (!seenBlocks.has(pred)) {
-          // NOTE: annotation required to actually typecheck and not silently infer `any`
-          const blockPhis = getOrInsertWith<BlockId, Array<PendingPhiOperand>>(
-            pendingPhis,
-            pred,
-            () => [],
-          );
-          blockPhis.push({from: operand, into: phi.place, index: index++});
-        } else {
-          state.assign(index++, operand, phi.place);
-        }
-      }
-    }
-    seenBlocks.add(block.id);
-
-    for (const instr of block.instructions) {
-      if (instr.effects == null) continue;
-      for (const effect of instr.effects) {
-        if (effect.kind === 'Create') {
-          state.create(effect.into, {kind: 'Object'});
-        } else if (effect.kind === 'CreateFunction') {
-          state.create(effect.into, {
-            kind: 'Function',
-            function: effect.function.loweredFunc.func,
-          });
-        } else if (effect.kind === 'CreateFrom') {
-          state.createFrom(index++, effect.from, effect.into);
-        } else if (effect.kind === 'Assign') {
-          /**
-           * TODO: Invariant that the node is not initialized yet
-           *
-           * InferFunctionExpressionAliasingEffectSignatures currently infers
-           * Assign effects in some places that should be Alias, leading to
-           * Assign effects that reinitialize a value. The end result appears to
-           * be fine, but we should fix that inference pass so that we add the
-           * invariant here.
-           */
-          if (!state.nodes.has(effect.into.identifier)) {
-            state.create(effect.into, {kind: 'Object'});
-          }
-          state.assign(index++, effect.from, effect.into);
-        } else if (effect.kind === 'Alias') {
-          state.assign(index++, effect.from, effect.into);
-        } else if (effect.kind === 'MaybeAlias') {
-          state.maybeAlias(index++, effect.from, effect.into);
-        } else if (effect.kind === 'Capture') {
-          state.capture(index++, effect.from, effect.into);
-        } else if (
-          effect.kind === 'MutateTransitive' ||
-          effect.kind === 'MutateTransitiveConditionally'
-        ) {
-          mutations.push({
-            index: index++,
-            id: instr.id,
-            transitive: true,
-            kind:
-              effect.kind === 'MutateTransitive'
-                ? MutationKind.Definite
-                : MutationKind.Conditional,
-            place: effect.value,
-          });
-        } else if (
-          effect.kind === 'Mutate' ||
-          effect.kind === 'MutateConditionally'
-        ) {
-          mutations.push({
-            index: index++,
-            id: instr.id,
-            transitive: false,
-            kind:
-              effect.kind === 'Mutate'
-                ? MutationKind.Definite
-                : MutationKind.Conditional,
-            place: effect.value,
-          });
-        } else if (
-          effect.kind === 'MutateFrozen' ||
-          effect.kind === 'MutateGlobal' ||
-          effect.kind === 'Impure'
-        ) {
-          errors.pushDiagnostic(effect.error);
-          functionEffects.push(effect);
-        } else if (effect.kind === 'Render') {
-          renders.push({index: index++, place: effect.place});
-          functionEffects.push(effect);
-        }
-      }
-    }
-    const blockPhis = pendingPhis.get(block.id);
-    if (blockPhis != null) {
-      for (const {from, into, index} of blockPhis) {
-        state.assign(index, from, into);
-      }
-    }
-    if (block.terminal.kind === 'return') {
-      state.assign(index++, block.terminal.value, fn.returns);
-    }
-
-    if (
-      (block.terminal.kind === 'maybe-throw' ||
-        block.terminal.kind === 'return') &&
-      block.terminal.effects != null
-    ) {
-      for (const effect of block.terminal.effects) {
-        if (effect.kind === 'Alias') {
-          state.assign(index++, effect.from, effect.into);
-        } else {
-          CompilerError.invariant(effect.kind === 'Freeze', {
-            reason: `Unexpected '${effect.kind}' effect for MaybeThrow terminal`,
-            loc: block.terminal.loc,
-          });
-        }
-      }
-    }
-  }
-
-  for (const mutation of mutations) {
-    state.mutate(
-      mutation.index,
-      mutation.place.identifier,
-      makeInstructionId(mutation.id + 1),
-      mutation.transitive,
-      mutation.kind,
-      mutation.place.loc,
-      errors,
-    );
-  }
-  for (const render of renders) {
-    state.render(render.index, render.place.identifier, errors);
-  }
-  for (const param of [...fn.context, ...fn.params]) {
-    const place = param.kind === 'Identifier' ? param : param.place;
-
-    const node = state.nodes.get(place.identifier);
-    if (node == null) {
-      continue;
-    }
-    let mutated = false;
-    if (node.local != null) {
-      if (node.local.kind === MutationKind.Conditional) {
-        mutated = true;
-        functionEffects.push({
-          kind: 'MutateConditionally',
-          value: {...place, loc: node.local.loc},
-        });
-      } else if (node.local.kind === MutationKind.Definite) {
-        mutated = true;
-        functionEffects.push({
-          kind: 'Mutate',
-          value: {...place, loc: node.local.loc},
-        });
-      }
-    }
-    if (node.transitive != null) {
-      if (node.transitive.kind === MutationKind.Conditional) {
-        mutated = true;
-        functionEffects.push({
-          kind: 'MutateTransitiveConditionally',
-          value: {...place, loc: node.transitive.loc},
-        });
-      } else if (node.transitive.kind === MutationKind.Definite) {
-        mutated = true;
-        functionEffects.push({
-          kind: 'MutateTransitive',
-          value: {...place, loc: node.transitive.loc},
-        });
-      }
-    }
-    if (mutated) {
-      place.effect = Effect.Capture;
-    }
-  }
-
-  /**
-   * Part 2
-   * Add legacy operand-specific effects based on instruction effects and mutable ranges.
-   * Also fixes up operand mutable ranges, making sure that start is non-zero if the value
-   * is mutated (depended on by later passes like InferReactiveScopeVariables which uses this
-   * to filter spurious mutations of globals, which we now guard against more precisely)
-   */
-  for (const block of fn.body.blocks.values()) {
-    for (const phi of block.phis) {
-      // TODO: we don't actually set these effects today!
-      phi.place.effect = Effect.Store;
-      const isPhiMutatedAfterCreation: boolean =
-        phi.place.identifier.mutableRange.end >
-        (block.instructions.at(0)?.id ?? block.terminal.id);
-      for (const operand of phi.operands.values()) {
-        operand.effect = isPhiMutatedAfterCreation
-          ? Effect.Capture
-          : Effect.Read;
-      }
-      if (
-        isPhiMutatedAfterCreation &&
-        phi.place.identifier.mutableRange.start === 0
-      ) {
-        /*
-         * TODO: ideally we'd construct a precise start range, but what really
-         * matters is that the phi's range appears mutable (end > start + 1)
-         * so we just set the start to the previous instruction before this block
-         */
-        const firstInstructionIdOfBlock =
-          block.instructions.at(0)?.id ?? block.terminal.id;
-        phi.place.identifier.mutableRange.start = makeInstructionId(
-          firstInstructionIdOfBlock - 1,
-        );
-      }
-    }
-    for (const instr of block.instructions) {
-      for (const lvalue of eachInstructionLValue(instr)) {
-        lvalue.effect = Effect.ConditionallyMutate;
-        if (lvalue.identifier.mutableRange.start === 0) {
-          lvalue.identifier.mutableRange.start = instr.id;
-        }
-        if (lvalue.identifier.mutableRange.end === 0) {
-          lvalue.identifier.mutableRange.end = makeInstructionId(
-            Math.max(instr.id + 1, lvalue.identifier.mutableRange.end),
-          );
-        }
-      }
-      for (const operand of eachInstructionValueOperand(instr.value)) {
-        operand.effect = Effect.Read;
-      }
-      if (instr.effects == null) {
-        continue;
-      }
-      const operandEffects = new Map<IdentifierId, Effect>();
-      for (const effect of instr.effects) {
-        switch (effect.kind) {
-          case 'Assign':
-          case 'Alias':
-          case 'Capture':
-          case 'CreateFrom':
-          case 'MaybeAlias': {
-            const isMutatedOrReassigned =
-              effect.into.identifier.mutableRange.end > instr.id;
-            if (isMutatedOrReassigned) {
-              operandEffects.set(effect.from.identifier.id, Effect.Capture);
-              operandEffects.set(effect.into.identifier.id, Effect.Store);
-            } else {
-              operandEffects.set(effect.from.identifier.id, Effect.Read);
-              operandEffects.set(effect.into.identifier.id, Effect.Store);
-            }
-            break;
-          }
-          case 'CreateFunction':
-          case 'Create': {
-            break;
-          }
-          case 'Mutate': {
-            operandEffects.set(effect.value.identifier.id, Effect.Store);
-            break;
-          }
-          case 'Apply': {
-            CompilerError.invariant(false, {
-              reason: `[AnalyzeFunctions] Expected Apply effects to be replaced with more precise effects`,
-              loc: effect.function.loc,
-            });
-          }
-          case 'MutateTransitive':
-          case 'MutateConditionally':
-          case 'MutateTransitiveConditionally': {
-            operandEffects.set(
-              effect.value.identifier.id,
-              Effect.ConditionallyMutate,
-            );
-            break;
-          }
-          case 'Freeze': {
-            operandEffects.set(effect.value.identifier.id, Effect.Freeze);
-            break;
-          }
-          case 'ImmutableCapture': {
-            // no-op, Read is the default
-            break;
-          }
-          case 'Impure':
-          case 'Render':
-          case 'MutateFrozen':
-          case 'MutateGlobal': {
-            // no-op
-            break;
-          }
-          default: {
-            assertExhaustive(
-              effect,
-              `Unexpected effect kind ${(effect as any).kind}`,
-            );
-          }
-        }
-      }
-      for (const lvalue of eachInstructionLValue(instr)) {
-        const effect =
-          operandEffects.get(lvalue.identifier.id) ??
-          Effect.ConditionallyMutate;
-        lvalue.effect = effect;
-      }
-      for (const operand of eachInstructionValueOperand(instr.value)) {
-        if (
-          operand.identifier.mutableRange.end > instr.id &&
-          operand.identifier.mutableRange.start === 0
-        ) {
-          operand.identifier.mutableRange.start = instr.id;
-        }
-        const effect = operandEffects.get(operand.identifier.id) ?? Effect.Read;
-        operand.effect = effect;
-      }
-
-      /**
-       * This case is targeted at hoisted functions like:
-       *
-       * ```
-       * x();
-       * function x() { ... }
-       * ```
-       *
-       * Which turns into:
-       *
-       * t0 = DeclareContext HoistedFunction x
-       * t1 = LoadContext x
-       * t2 = CallExpression t1 ( )
-       * t3 = FunctionExpression ...
-       * t4 = StoreContext Function x = t3
-       *
-       * If the function had captured mutable values, it would already have its
-       * range extended to include the StoreContext. But if the function doesn't
-       * capture any mutable values its range won't have been extended yet. We
-       * want to ensure that the value is memoized along with the context variable,
-       * not independently of it (bc of the way we do codegen for hoisted functions).
-       * So here we check for StoreContext rvalues and if they haven't already had
-       * their range extended to at least this instruction, we extend it.
-       */
-      if (
-        instr.value.kind === 'StoreContext' &&
-        instr.value.value.identifier.mutableRange.end <= instr.id
-      ) {
-        instr.value.value.identifier.mutableRange.end = makeInstructionId(
-          instr.id + 1,
-        );
-      }
-    }
-    if (block.terminal.kind === 'return') {
-      block.terminal.value.effect = isFunctionExpression
-        ? Effect.Read
-        : Effect.Freeze;
-    } else {
-      for (const operand of eachTerminalOperand(block.terminal)) {
-        operand.effect = Effect.Read;
-      }
-    }
-  }
-
-  /**
-   * Part 3
-   * Finish populating the externally visible effects. Above we bubble-up the side effects
-   * (MutateFrozen/MutableGlobal/Impure/Render) as well as mutations of context variables.
-   * Here we populate an effect to create the return value as well as populating alias/capture
-   * effects for how data flows between the params, context vars, and return.
-   */
-  const returns = fn.returns.identifier;
-  functionEffects.push({
-    kind: 'Create',
-    into: fn.returns,
-    value: isPrimitiveType(returns)
-      ? ValueKind.Primitive
-      : isJsxType(returns.type)
-        ? ValueKind.Frozen
-        : ValueKind.Mutable,
-    reason: ValueReason.KnownReturnSignature,
-  });
-  /**
-   * Determine precise data-flow effects by simulating transitive mutations of the params/
-   * captures and seeing what other params/context variables are affected. Anything that
-   * would be transitively mutated needs a capture relationship.
-   */
-  const tracked: Array<Place> = [];
-  const ignoredErrors = new CompilerError();
-  for (const param of [...fn.params, ...fn.context, fn.returns]) {
-    const place = param.kind === 'Identifier' ? param : param.place;
-    tracked.push(place);
-  }
-  for (const into of tracked) {
-    const mutationIndex = index++;
-    state.mutate(
-      mutationIndex,
-      into.identifier,
-      null,
-      true,
-      MutationKind.Conditional,
-      into.loc,
-      ignoredErrors,
-    );
-    for (const from of tracked) {
-      if (
-        from.identifier.id === into.identifier.id ||
-        from.identifier.id === fn.returns.identifier.id
-      ) {
-        continue;
-      }
-      const fromNode = state.nodes.get(from.identifier);
-      CompilerError.invariant(fromNode != null, {
-        reason: `Expected a node to exist for all parameters and context variables`,
-        loc: into.loc,
-      });
-      if (fromNode.lastMutated === mutationIndex) {
-        if (into.identifier.id === fn.returns.identifier.id) {
-          // The return value could be any of the params/context variables
-          functionEffects.push({
-            kind: 'Alias',
-            from,
-            into,
-          });
-        } else {
-          // Otherwise params/context-vars can only capture each other
-          functionEffects.push({
-            kind: 'Capture',
-            from,
-            into,
-          });
-        }
-      }
-    }
-  }
-
-  if (errors.hasErrors() && !isFunctionExpression) {
-    return Err(errors);
-  }
-  return Ok(functionEffects);
-}
-
-function appendFunctionErrors(errors: CompilerError, fn: HIRFunction): void {
-  for (const effect of fn.aliasingEffects ?? []) {
-    switch (effect.kind) {
-      case 'Impure':
-      case 'MutateFrozen':
-      case 'MutateGlobal': {
-        errors.pushDiagnostic(effect.error);
-        break;
-      }
-    }
-  }
-}
-
-export enum MutationKind {
-  None = 0,
-  Conditional = 1,
-  Definite = 2,
-}
-
-type Node = {
-  id: Identifier;
-  createdFrom: Map<Identifier, number>;
-  captures: Map<Identifier, number>;
-  aliases: Map<Identifier, number>;
-  maybeAliases: Map<Identifier, number>;
-  edges: Array<{
-    index: number;
-    node: Identifier;
-    kind: 'capture' | 'alias' | 'maybeAlias';
-  }>;
-  transitive: {kind: MutationKind; loc: SourceLocation} | null;
-  local: {kind: MutationKind; loc: SourceLocation} | null;
-  lastMutated: number;
-  value:
-    | {kind: 'Object'}
-    | {kind: 'Phi'}
-    | {kind: 'Function'; function: HIRFunction};
-};
-class AliasingState {
-  nodes: Map<Identifier, Node> = new Map();
-
-  create(place: Place, value: Node['value']): void {
-    this.nodes.set(place.identifier, {
-      id: place.identifier,
-      createdFrom: new Map(),
-      captures: new Map(),
-      aliases: new Map(),
-      maybeAliases: new Map(),
-      edges: [],
-      transitive: null,
-      local: null,
-      lastMutated: 0,
-      value,
-    });
-  }
-
-  createFrom(index: number, from: Place, into: Place): void {
-    this.create(into, {kind: 'Object'});
-    const fromNode = this.nodes.get(from.identifier);
-    const toNode = this.nodes.get(into.identifier);
-    if (fromNode == null || toNode == null) {
-      return;
-    }
-    fromNode.edges.push({index, node: into.identifier, kind: 'alias'});
-    if (!toNode.createdFrom.has(from.identifier)) {
-      toNode.createdFrom.set(from.identifier, index);
-    }
-  }
-
-  capture(index: number, from: Place, into: Place): void {
-    const fromNode = this.nodes.get(from.identifier);
-    const toNode = this.nodes.get(into.identifier);
-    if (fromNode == null || toNode == null) {
-      return;
-    }
-    fromNode.edges.push({index, node: into.identifier, kind: 'capture'});
-    if (!toNode.captures.has(from.identifier)) {
-      toNode.captures.set(from.identifier, index);
-    }
-  }
-
-  assign(index: number, from: Place, into: Place): void {
-    const fromNode = this.nodes.get(from.identifier);
-    const toNode = this.nodes.get(into.identifier);
-    if (fromNode == null || toNode == null) {
-      return;
-    }
-    fromNode.edges.push({index, node: into.identifier, kind: 'alias'});
-    if (!toNode.aliases.has(from.identifier)) {
-      toNode.aliases.set(from.identifier, index);
-    }
-  }
-
-  maybeAlias(index: number, from: Place, into: Place): void {
-    const fromNode = this.nodes.get(from.identifier);
-    const toNode = this.nodes.get(into.identifier);
-    if (fromNode == null || toNode == null) {
-      return;
-    }
-    fromNode.edges.push({index, node: into.identifier, kind: 'maybeAlias'});
-    if (!toNode.maybeAliases.has(from.identifier)) {
-      toNode.maybeAliases.set(from.identifier, index);
-    }
-  }
-
-  render(index: number, start: Identifier, errors: CompilerError): void {
-    const seen = new Set<Identifier>();
-    const queue: Array<Identifier> = [start];
-    while (queue.length !== 0) {
-      const current = queue.pop()!;
-      if (seen.has(current)) {
-        continue;
-      }
-      seen.add(current);
-      const node = this.nodes.get(current);
-      if (node == null || node.transitive != null || node.local != null) {
-        continue;
-      }
-      if (node.value.kind === 'Function') {
-        appendFunctionErrors(errors, node.value.function);
-      }
-      for (const [alias, when] of node.createdFrom) {
-        if (when >= index) {
-          continue;
-        }
-        queue.push(alias);
-      }
-      for (const [alias, when] of node.aliases) {
-        if (when >= index) {
-          continue;
-        }
-        queue.push(alias);
-      }
-      for (const [capture, when] of node.captures) {
-        if (when >= index) {
-          continue;
-        }
-        queue.push(capture);
-      }
-    }
-  }
-
-  mutate(
-    index: number,
-    start: Identifier,
-    // Null is used for simulated mutations
-    end: InstructionId | null,
-    transitive: boolean,
-    startKind: MutationKind,
-    loc: SourceLocation,
-    errors: CompilerError,
-  ): void {
-    const seen = new Map<Identifier, MutationKind>();
-    const queue: Array<{
-      place: Identifier;
-      transitive: boolean;
-      direction: 'backwards' | 'forwards';
-      kind: MutationKind;
-    }> = [{place: start, transitive, direction: 'backwards', kind: startKind}];
-    while (queue.length !== 0) {
-      const {place: current, transitive, direction, kind} = queue.pop()!;
-      const previousKind = seen.get(current);
-      if (previousKind != null && previousKind >= kind) {
-        continue;
-      }
-      seen.set(current, kind);
-      const node = this.nodes.get(current);
-      if (node == null) {
-        continue;
-      }
-      node.lastMutated = Math.max(node.lastMutated, index);
-      if (end != null) {
-        node.id.mutableRange.end = makeInstructionId(
-          Math.max(node.id.mutableRange.end, end),
-        );
-      }
-      if (
-        node.value.kind === 'Function' &&
-        node.transitive == null &&
-        node.local == null
-      ) {
-        appendFunctionErrors(errors, node.value.function);
-      }
-      if (transitive) {
-        if (node.transitive == null || node.transitive.kind < kind) {
-          node.transitive = {kind, loc};
-        }
-      } else {
-        if (node.local == null || node.local.kind < kind) {
-          node.local = {kind, loc};
-        }
-      }
-      /**
-       * all mutations affect "forward" edges by the rules:
-       * - Capture a -> b, mutate(a) => mutate(b)
-       * - Alias a -> b, mutate(a) => mutate(b)
-       */
-      for (const edge of node.edges) {
-        if (edge.index >= index) {
-          break;
-        }
-        queue.push({place: edge.node, transitive, direction: 'forwards', kind});
-      }
-      for (const [alias, when] of node.createdFrom) {
-        if (when >= index) {
-          continue;
-        }
-        queue.push({
-          place: alias,
-          transitive: true,
-          direction: 'backwards',
-          kind,
-        });
-      }
-      if (direction === 'backwards' || node.value.kind !== 'Phi') {
-        /**
-         * all mutations affect backward alias edges by the rules:
-         * - Alias a -> b, mutate(b) => mutate(a)
-         * - Alias a -> b, mutateTransitive(b) => mutate(a)
-         *
-         * However, if we reached a phi because one of its inputs was mutated
-         * (and we're advancing "forwards" through that node's edges), then
-         * we know we've already processed the mutation at its source. The
-         * phi's other inputs can't be affected.
-         */
-        for (const [alias, when] of node.aliases) {
-          if (when >= index) {
-            continue;
-          }
-          queue.push({place: alias, transitive, direction: 'backwards', kind});
-        }
-        /**
-         * MaybeAlias indicates potential data flow from unknown function calls,
-         * so we downgrade mutations through these aliases to consider them
-         * conditional. This means we'll consider them for mutation *range*
-         * purposes but not report validation errors for mutations, since
-         * we aren't sure that the `from` value could actually be aliased.
-         */
-        for (const [alias, when] of node.maybeAliases) {
-          if (when >= index) {
-            continue;
-          }
-          queue.push({
-            place: alias,
-            transitive,
-            direction: 'backwards',
-            kind: MutationKind.Conditional,
-          });
-        }
-      }
-      /**
-       * but only transitive mutations affect captures
-       */
-      if (transitive) {
-        for (const [capture, when] of node.captures) {
-          if (when >= index) {
-            continue;
-          }
-          queue.push({
-            place: capture,
-            transitive,
-            direction: 'backwards',
-            kind,
-          });
-        }
-      }
-    }
-  }
-}

compiler/packages/babel-plugin-react-compiler/src/Inference/InferReactivePlaces.ts

@@ -9,23 +9,18 @@ import {CompilerError} from '..';
 import {
   BlockId,
   Effect,
-  Environment,
   HIRFunction,
   Identifier,
   IdentifierId,
-  Instruction,
   Place,
   computePostDominatorTree,
-  evaluatesToStableTypeOrContainer,
   getHookKind,
   isStableType,
-  isStableTypeContainer,
   isUseOperator,
 } from '../HIR';
 import {PostDominator} from '../HIR/Dominator';
 import {
   eachInstructionLValue,
-  eachInstructionOperand,
   eachInstructionValueOperand,
   eachTerminalOperand,
 } from '../HIR/visitors';
@@ -36,96 +31,6 @@ import {
 import DisjointSet from '../Utils/DisjointSet';
 import {assertExhaustive} from '../Utils/utils';
 
-/**
- * Side map to track and propagate sources of stability (i.e. hook calls such as
- * `useRef()` and property reads such as `useState()[1]). Note that this
- * requires forward data flow analysis since stability is not part of React
- * Compiler's type system.
- */
-class StableSidemap {
-  map: Map<IdentifierId, {isStable: boolean}> = new Map();
-  env: Environment;
-
-  constructor(env: Environment) {
-    this.env = env;
-  }
-
-  handleInstruction(instr: Instruction): void {
-    const {value, lvalue} = instr;
-
-    switch (value.kind) {
-      case 'CallExpression':
-      case 'MethodCall': {
-        /**
-         * Sources of stability are known hook calls
-         */
-        if (evaluatesToStableTypeOrContainer(this.env, instr)) {
-          if (isStableType(lvalue.identifier)) {
-            this.map.set(lvalue.identifier.id, {
-              isStable: true,
-            });
-          } else {
-            this.map.set(lvalue.identifier.id, {
-              isStable: false,
-            });
-          }
-        }
-        break;
-      }
-
-      case 'Destructure':
-      case 'PropertyLoad': {
-        /**
-         * PropertyLoads may from stable containers may also produce stable
-         * values. ComputedLoads are technically safe for now (as all stable
-         * containers have differently-typed elements), but are not handled as
-         * they should be rare anyways.
-         */
-        const source =
-          value.kind === 'Destructure'
-            ? value.value.identifier.id
-            : value.object.identifier.id;
-        const entry = this.map.get(source);
-        if (entry) {
-          for (const lvalue of eachInstructionLValue(instr)) {
-            if (isStableTypeContainer(lvalue.identifier)) {
-              this.map.set(lvalue.identifier.id, {
-                isStable: false,
-              });
-            } else if (isStableType(lvalue.identifier)) {
-              this.map.set(lvalue.identifier.id, {
-                isStable: true,
-              });
-            }
-          }
-        }
-        break;
-      }
-
-      case 'StoreLocal': {
-        const entry = this.map.get(value.value.identifier.id);
-        if (entry) {
-          this.map.set(lvalue.identifier.id, entry);
-          this.map.set(value.lvalue.place.identifier.id, entry);
-        }
-        break;
-      }
-
-      case 'LoadLocal': {
-        const entry = this.map.get(value.place.identifier.id);
-        if (entry) {
-          this.map.set(lvalue.identifier.id, entry);
-        }
-        break;
-      }
-    }
-  }
-
-  isStable(id: IdentifierId): boolean {
-    const entry = this.map.get(id);
-    return entry != null ? entry.isStable : false;
-  }
-}
 /*
  * Infers which `Place`s are reactive, ie may *semantically* change
  * over the course of the component/hook's lifetime. Places are reactive
@@ -206,7 +111,6 @@ class StableSidemap {
  */
 export function inferReactivePlaces(fn: HIRFunction): void {
   const reactiveIdentifiers = new ReactivityMap(findDisjointMutableValues(fn));
-  const stableIdentifierSources = new StableSidemap(fn.env);
   for (const param of fn.params) {
     const place = param.kind === 'Identifier' ? param : param.place;
     reactiveIdentifiers.markReactive(place);
@@ -280,12 +184,11 @@ export function inferReactivePlaces(fn: HIRFunction): void {
         }
       }
       for (const instruction of block.instructions) {
-        stableIdentifierSources.handleInstruction(instruction);
         const {value} = instruction;
         let hasReactiveInput = false;
         /*
          * NOTE: we want to mark all operands as reactive or not, so we
-         * avoid short-circuiting here
+         * avoid short-circuting here
          */
         for (const operand of eachInstructionValueOperand(value)) {
           const reactive = reactiveIdentifiers.isReactive(operand);
@@ -315,13 +218,7 @@ export function inferReactivePlaces(fn: HIRFunction): void {
 
         if (hasReactiveInput) {
           for (const lvalue of eachInstructionLValue(instruction)) {
-            /**
-             * Note that it's not correct to mark all stable-typed identifiers
-             * as non-reactive, since ternaries and other value blocks can
-             * produce reactive identifiers typed as these.
-             * (e.g. `props.cond ? setState1 : setState2`)
-             */
-            if (stableIdentifierSources.isStable(lvalue.identifier.id)) {
+            if (isStableType(lvalue.identifier)) {
               continue;
             }
             reactiveIdentifiers.markReactive(lvalue);
@@ -333,7 +230,6 @@ export function inferReactivePlaces(fn: HIRFunction): void {
               case Effect.Capture:
               case Effect.Store:
               case Effect.ConditionallyMutate:
-              case Effect.ConditionallyMutateIterator:
               case Effect.Mutate: {
                 if (isMutable(instruction, operand)) {
                   reactiveIdentifiers.markReactive(operand);
@@ -368,41 +264,6 @@ export function inferReactivePlaces(fn: HIRFunction): void {
       }
     }
   } while (reactiveIdentifiers.snapshot());
-
-  function propagateReactivityToInnerFunctions(
-    fn: HIRFunction,
-    isOutermost: boolean,
-  ): void {
-    for (const [, block] of fn.body.blocks) {
-      for (const instr of block.instructions) {
-        if (!isOutermost) {
-          for (const operand of eachInstructionOperand(instr)) {
-            reactiveIdentifiers.isReactive(operand);
-          }
-        }
-        if (
-          instr.value.kind === 'ObjectMethod' ||
-          instr.value.kind === 'FunctionExpression'
-        ) {
-          propagateReactivityToInnerFunctions(
-            instr.value.loweredFunc.func,
-            false,
-          );
-        }
-      }
-      if (!isOutermost) {
-        for (const operand of eachTerminalOperand(block.terminal)) {
-          reactiveIdentifiers.isReactive(operand);
-        }
-      }
-    }
-  }
-
-  /**
-   * Propagate reactivity for inner functions, as we eventually hoist and dedupe
-   * dependency instructions for scopes.
-   */
-  propagateReactivityToInnerFunctions(fn, true);
 }
 
 /*

compiler/packages/babel-plugin-react-compiler/src/Inference/InferReferenceEffects.ts

@@ -5,14 +5,13 @@
  * LICENSE file in the root directory of this source tree.
  */
 
-import {CompilerError, CompilerErrorDetailOptions} from '../CompilerError';
+import {CompilerError} from '../CompilerError';
 import {Environment} from '../HIR';
 import {
   AbstractValue,
   BasicBlock,
   BlockId,
   CallExpression,
-  NewExpression,
   Effect,
   FunctionEffect,
   GeneratedSource,
@@ -24,15 +23,12 @@ import {
   Phi,
   Place,
   SpreadPattern,
-  TInstruction,
   Type,
   ValueKind,
   ValueReason,
   isArrayType,
-  isMapType,
   isMutableEffect,
   isObjectType,
-  isSetType,
 } from '../HIR/HIR';
 import {FunctionSignature} from '../HIR/ObjectShape';
 import {
@@ -42,17 +38,18 @@ import {
   printSourceLocation,
 } from '../HIR/PrintHIR';
 import {
+  eachCallArgument,
   eachInstructionOperand,
   eachInstructionValueOperand,
   eachPatternOperand,
   eachTerminalOperand,
   eachTerminalSuccessor,
 } from '../HIR/visitors';
-import {assertExhaustive, Set_isSuperset} from '../Utils/utils';
+import {assertExhaustive} from '../Utils/utils';
 import {
   inferTerminalFunctionEffects,
   inferInstructionFunctionEffects,
-  transformFunctionEffectErrors,
+  raiseFunctionEffectErrors,
 } from './InferFunctionEffects';
 
 const UndefinedValue: InstructionValue = {
@@ -106,15 +103,12 @@ const UndefinedValue: InstructionValue = {
 export default function inferReferenceEffects(
   fn: HIRFunction,
   options: {isFunctionExpression: boolean} = {isFunctionExpression: false},
-): Array<CompilerErrorDetailOptions> {
+): void {
   /*
    * Initial state contains function params
    * TODO: include module declarations here as well
    */
-  const initialState = InferenceState.empty(
-    fn.env,
-    options.isFunctionExpression,
-  );
+  const initialState = InferenceState.empty(fn.env);
   const value: InstructionValue = {
     kind: 'Primitive',
     loc: fn.loc,
@@ -247,9 +241,8 @@ export default function inferReferenceEffects(
 
   if (options.isFunctionExpression) {
     fn.effects = functionEffects;
-    return [];
-  } else {
-    return transformFunctionEffectErrors(functionEffects);
+  } else if (!fn.env.config.enableMinimalTransformsForRetry) {
+    raiseFunctionEffectErrors(functionEffects);
   }
 }
 
@@ -257,8 +250,7 @@ type FreezeAction = {values: Set<InstructionValue>; reason: Set<ValueReason>};
 
 // Maintains a mapping of top-level variables to the kind of value they hold
 class InferenceState {
-  env: Environment;
-  #isFunctionExpression: boolean;
+  #env: Environment;
 
   // The kind of each value, based on its allocation site
   #values: Map<InstructionValue, AbstractValue>;
@@ -271,25 +263,16 @@ class InferenceState {
 
   constructor(
     env: Environment,
-    isFunctionExpression: boolean,
     values: Map<InstructionValue, AbstractValue>,
     variables: Map<IdentifierId, Set<InstructionValue>>,
   ) {
-    this.env = env;
-    this.#isFunctionExpression = isFunctionExpression;
+    this.#env = env;
     this.#values = values;
     this.#variables = variables;
   }
 
-  static empty(
-    env: Environment,
-    isFunctionExpression: boolean,
-  ): InferenceState {
-    return new InferenceState(env, isFunctionExpression, new Map(), new Map());
-  }
-
-  get isFunctionExpression(): boolean {
-    return this.#isFunctionExpression;
+  static empty(env: Environment): InferenceState {
+    return new InferenceState(env, new Map(), new Map());
   }
 
   // (Re)initializes a @param value with its default @param kind.
@@ -407,14 +390,9 @@ class InferenceState {
 
   freezeValues(values: Set<InstructionValue>, reason: Set<ValueReason>): void {
     for (const value of values) {
-      if (
-        value.kind === 'DeclareContext' ||
-        (value.kind === 'StoreContext' &&
-          (value.lvalue.kind === InstructionKind.Let ||
-            value.lvalue.kind === InstructionKind.Const))
-      ) {
+      if (value.kind === 'DeclareContext') {
         /**
-         * Avoid freezing context variable declarations, hoisted or otherwise
+         * Avoid freezing hoisted context declarations
          * function Component() {
          *   const cb = useBar(() => foo(2)); // produces a hoisted context declaration
          *   const foo = useFoo();            // reassigns to the context variable
@@ -430,8 +408,8 @@ class InferenceState {
       });
       if (
         value.kind === 'FunctionExpression' &&
-        (this.env.config.enablePreserveExistingMemoizationGuarantees ||
-          this.env.config.enableTransitivelyFreezeFunctionExpressions)
+        (this.#env.config.enablePreserveExistingMemoizationGuarantees ||
+          this.#env.config.enableTransitivelyFreezeFunctionExpressions)
       ) {
         for (const operand of value.loweredFunc.func.context) {
           const operandValues = this.#variables.get(operand.identifier.id);
@@ -489,25 +467,6 @@ class InferenceState {
         }
         break;
       }
-      case Effect.ConditionallyMutateIterator: {
-        if (
-          valueKind.kind === ValueKind.Mutable ||
-          valueKind.kind === ValueKind.Context
-        ) {
-          if (
-            isArrayType(place.identifier) ||
-            isSetType(place.identifier) ||
-            isMapType(place.identifier)
-          ) {
-            effect = Effect.Capture;
-          } else {
-            effect = Effect.ConditionallyMutate;
-          }
-        } else {
-          effect = Effect.Read;
-        }
-        break;
-      }
       case Effect.Mutate: {
         effect = Effect.Mutate;
         break;
@@ -630,8 +589,7 @@ class InferenceState {
       return null;
     } else {
       return new InferenceState(
-        this.env,
-        this.#isFunctionExpression,
+        this.#env,
         nextValues ?? new Map(this.#values),
         nextVariables ?? new Map(this.#variables),
       );
@@ -645,8 +603,7 @@ class InferenceState {
    */
   clone(): InferenceState {
     return new InferenceState(
-      this.env,
-      this.#isFunctionExpression,
+      this.#env,
       new Map(this.#values),
       new Map(this.#variables),
     );
@@ -779,7 +736,7 @@ function inferParam(
  * │         Mutable          │───┘
  * └──────────────────────────┘
  */
-export function mergeValueKinds(a: ValueKind, b: ValueKind): ValueKind {
+function mergeValues(a: ValueKind, b: ValueKind): ValueKind {
   if (a === b) {
     return a;
   } else if (a === ValueKind.MaybeFrozen || b === ValueKind.MaybeFrozen) {
@@ -821,16 +778,28 @@ export function mergeValueKinds(a: ValueKind, b: ValueKind): ValueKind {
   }
 }
 
+/**
+ * @returns `true` if `a` is a superset of `b`.
+ */
+function isSuperset<T>(a: ReadonlySet<T>, b: ReadonlySet<T>): boolean {
+  for (const v of b) {
+    if (!a.has(v)) {
+      return false;
+    }
+  }
+  return true;
+}
+
 function mergeAbstractValues(
   a: AbstractValue,
   b: AbstractValue,
 ): AbstractValue {
-  const kind = mergeValueKinds(a.kind, b.kind);
+  const kind = mergeValues(a.kind, b.kind);
   if (
     kind === a.kind &&
     kind === b.kind &&
-    Set_isSuperset(a.reason, b.reason) &&
-    Set_isSuperset(a.context, b.context)
+    isSuperset(a.reason, b.reason) &&
+    isSuperset(a.context, b.context)
   ) {
     return a;
   }
@@ -909,7 +878,9 @@ function inferBlock(
             state.referenceAndRecordEffects(
               freezeActions,
               element.place,
-              Effect.ConditionallyMutateIterator,
+              isArrayType(element.place.identifier)
+                ? Effect.Capture
+                : Effect.ConditionallyMutate,
               ValueReason.Other,
             );
           } else if (element.kind === 'Identifier') {
@@ -932,12 +903,43 @@ function inferBlock(
         break;
       }
       case 'NewExpression': {
-        inferCallEffects(
-          state,
-          instr as TInstruction<NewExpression>,
+        /**
+         * For new expressions, we infer a `read` effect on the Class / Function type
+         * to avoid extending mutable ranges of locally created classes, e.g.
+         * ```js
+         * const MyClass = getClass();
+         * const value = new MyClass(val1, val2)
+         *                   ^ (read)   ^ (conditionally mutate)
+         * ```
+         *
+         * Risks:
+         * Classes / functions created during render could technically capture and
+         * mutate their enclosing scope, which we currently do not detect.
+         */
+        const valueKind: AbstractValue = {
+          kind: ValueKind.Mutable,
+          reason: new Set([ValueReason.Other]),
+          context: new Set(),
+        };
+        state.referenceAndRecordEffects(
           freezeActions,
-          getFunctionCallSignature(env, instrValue.callee.identifier.type),
+          instrValue.callee,
+          Effect.Read,
+          ValueReason.Other,
         );
+
+        for (const operand of eachCallArgument(instrValue.args)) {
+          state.referenceAndRecordEffects(
+            freezeActions,
+            operand,
+            Effect.ConditionallyMutate,
+            ValueReason.Other,
+          );
+        }
+
+        state.initialize(instrValue, valueKind);
+        state.define(instr.lvalue, instrValue);
+        instr.lvalue.effect = Effect.ConditionallyMutate;
         continuation = {kind: 'funeffects'};
         break;
       }
@@ -1235,12 +1237,62 @@ function inferBlock(
         break;
       }
       case 'CallExpression': {
-        inferCallEffects(
-          state,
-          instr as TInstruction<CallExpression>,
-          freezeActions,
-          getFunctionCallSignature(env, instrValue.callee.identifier.type),
+        const signature = getFunctionCallSignature(
+          env,
+          instrValue.callee.identifier.type,
         );
+
+        const effects =
+          signature !== null ? getFunctionEffects(instrValue, signature) : null;
+        const returnValueKind: AbstractValue =
+          signature !== null
+            ? {
+                kind: signature.returnValueKind,
+                reason: new Set([
+                  signature.returnValueReason ??
+                    ValueReason.KnownReturnSignature,
+                ]),
+                context: new Set(),
+              }
+            : {
+                kind: ValueKind.Mutable,
+                reason: new Set([ValueReason.Other]),
+                context: new Set(),
+              };
+        let hasCaptureArgument = false;
+        for (let i = 0; i < instrValue.args.length; i++) {
+          const arg = instrValue.args[i];
+          const place = arg.kind === 'Identifier' ? arg : arg.place;
+          state.referenceAndRecordEffects(
+            freezeActions,
+            place,
+            getArgumentEffect(effects != null ? effects[i] : null, arg),
+            ValueReason.Other,
+          );
+          hasCaptureArgument ||= place.effect === Effect.Capture;
+        }
+        if (signature !== null) {
+          state.referenceAndRecordEffects(
+            freezeActions,
+            instrValue.callee,
+            signature.calleeEffect,
+            ValueReason.Other,
+          );
+        } else {
+          state.referenceAndRecordEffects(
+            freezeActions,
+            instrValue.callee,
+            Effect.ConditionallyMutate,
+            ValueReason.Other,
+          );
+        }
+        hasCaptureArgument ||= instrValue.callee.effect === Effect.Capture;
+
+        state.initialize(instrValue, returnValueKind);
+        state.define(instr.lvalue, instrValue);
+        instr.lvalue.effect = hasCaptureArgument
+          ? Effect.Store
+          : Effect.ConditionallyMutate;
         continuation = {kind: 'funeffects'};
         break;
       }
@@ -1258,12 +1310,102 @@ function inferBlock(
           Effect.Read,
           ValueReason.Other,
         );
-        inferCallEffects(
-          state,
-          instr as TInstruction<MethodCall>,
-          freezeActions,
-          getFunctionCallSignature(env, instrValue.property.identifier.type),
+
+        const signature = getFunctionCallSignature(
+          env,
+          instrValue.property.identifier.type,
         );
+
+        const returnValueKind: AbstractValue =
+          signature !== null
+            ? {
+                kind: signature.returnValueKind,
+                reason: new Set([
+                  signature.returnValueReason ??
+                    ValueReason.KnownReturnSignature,
+                ]),
+                context: new Set(),
+              }
+            : {
+                kind: ValueKind.Mutable,
+                reason: new Set([ValueReason.Other]),
+                context: new Set(),
+              };
+
+        if (
+          signature !== null &&
+          signature.mutableOnlyIfOperandsAreMutable &&
+          areArgumentsImmutableAndNonMutating(state, instrValue.args)
+        ) {
+          /*
+           * None of the args are mutable or mutate their params, we can downgrade to
+           * treating as all reads (except that the receiver may be captured)
+           */
+          for (const arg of instrValue.args) {
+            const place = arg.kind === 'Identifier' ? arg : arg.place;
+            state.referenceAndRecordEffects(
+              freezeActions,
+              place,
+              Effect.Read,
+              ValueReason.Other,
+            );
+          }
+          state.referenceAndRecordEffects(
+            freezeActions,
+            instrValue.receiver,
+            Effect.Capture,
+            ValueReason.Other,
+          );
+          state.initialize(instrValue, returnValueKind);
+          state.define(instr.lvalue, instrValue);
+          instr.lvalue.effect =
+            instrValue.receiver.effect === Effect.Capture
+              ? Effect.Store
+              : Effect.ConditionallyMutate;
+          continuation = {kind: 'funeffects'};
+          break;
+        }
+
+        const effects =
+          signature !== null ? getFunctionEffects(instrValue, signature) : null;
+        let hasCaptureArgument = false;
+        for (let i = 0; i < instrValue.args.length; i++) {
+          const arg = instrValue.args[i];
+          const place = arg.kind === 'Identifier' ? arg : arg.place;
+          /*
+           * If effects are inferred for an argument, we should fail invalid
+           * mutating effects
+           */
+          state.referenceAndRecordEffects(
+            freezeActions,
+            place,
+            getArgumentEffect(effects != null ? effects[i] : null, arg),
+            ValueReason.Other,
+          );
+          hasCaptureArgument ||= place.effect === Effect.Capture;
+        }
+        if (signature !== null) {
+          state.referenceAndRecordEffects(
+            freezeActions,
+            instrValue.receiver,
+            signature.calleeEffect,
+            ValueReason.Other,
+          );
+        } else {
+          state.referenceAndRecordEffects(
+            freezeActions,
+            instrValue.receiver,
+            Effect.ConditionallyMutate,
+            ValueReason.Other,
+          );
+        }
+        hasCaptureArgument ||= instrValue.receiver.effect === Effect.Capture;
+
+        state.initialize(instrValue, returnValueKind);
+        state.define(instr.lvalue, instrValue);
+        instr.lvalue.effect = hasCaptureArgument
+          ? Effect.Store
+          : Effect.ConditionallyMutate;
         continuation = {kind: 'funeffects'};
         break;
       }
@@ -1599,14 +1741,6 @@ function inferBlock(
         );
 
         const lvalue = instr.lvalue;
-        if (instrValue.lvalue.kind !== InstructionKind.Reassign) {
-          state.initialize(instrValue, {
-            kind: ValueKind.Mutable,
-            reason: new Set([ValueReason.Other]),
-            context: new Set(),
-          });
-          state.define(instrValue.lvalue.place, instrValue);
-        }
         state.alias(lvalue, instrValue.value);
         lvalue.effect = Effect.Store;
         continuation = {kind: 'funeffects'};
@@ -1678,13 +1812,7 @@ function inferBlock(
           kind === ValueKind.Mutable || kind === ValueKind.Context;
         let effect;
         let valueKind: AbstractValue;
-        const iterator = instrValue.collection.identifier;
-        if (
-          !isMutable ||
-          isArrayType(iterator) ||
-          isMapType(iterator) ||
-          isSetType(iterator)
-        ) {
+        if (!isMutable || isArrayType(instrValue.collection.identifier)) {
           // Case 1, assume iterator is a separate mutable object
           effect = {
             kind: Effect.Read,
@@ -1725,7 +1853,7 @@ function inferBlock(
         state.referenceAndRecordEffects(
           freezeActions,
           instrValue.iterator,
-          Effect.ConditionallyMutateIterator,
+          Effect.ConditionallyMutate,
           ValueReason.Other,
         );
         /**
@@ -1797,15 +1925,8 @@ function inferBlock(
     if (block.terminal.kind === 'return' || block.terminal.kind === 'throw') {
       if (
         state.isDefined(operand) &&
-        ((operand.identifier.type.kind === 'Function' &&
-          state.isFunctionExpression) ||
-          state.kind(operand).kind === ValueKind.Context)
+        state.kind(operand).kind === ValueKind.Context
       ) {
-        /**
-         * Returned values should only be typed as 'frozen' if they are both (1)
-         * local and (2) not a function expression which may capture and mutate
-         * this function's outer context.
-         */
         effect = Effect.ConditionallyMutate;
       } else {
         effect = Effect.Freeze;
@@ -1861,7 +1982,7 @@ export function getFunctionCallSignature(
  * @returns Inferred effects of function arguments, or null if inference fails.
  */
 export function getFunctionEffects(
-  fn: MethodCall | CallExpression | NewExpression,
+  fn: MethodCall | CallExpression,
   sig: FunctionSignature,
 ): Array<Effect> | null {
   const results = [];
@@ -1890,33 +2011,6 @@ export function getFunctionEffects(
   return results;
 }
 
-export function isKnownMutableEffect(effect: Effect): boolean {
-  switch (effect) {
-    case Effect.Store:
-    case Effect.ConditionallyMutate:
-    case Effect.ConditionallyMutateIterator:
-    case Effect.Mutate: {
-      return true;
-    }
-
-    case Effect.Unknown: {
-      CompilerError.invariant(false, {
-        reason: 'Unexpected unknown effect',
-        description: null,
-        loc: GeneratedSource,
-        suggestions: null,
-      });
-    }
-    case Effect.Read:
-    case Effect.Capture:
-    case Effect.Freeze: {
-      return false;
-    }
-    default: {
-      assertExhaustive(effect, `Unexpected effect \`${effect}\``);
-    }
-  }
-}
 /**
  * Returns true if all of the arguments are both non-mutable (immutable or frozen)
  * _and_ are not functions which might mutate their arguments. Note that function
@@ -1928,20 +2022,10 @@ function areArgumentsImmutableAndNonMutating(
   args: MethodCall['args'],
 ): boolean {
   for (const arg of args) {
-    if (arg.kind === 'Identifier' && arg.identifier.type.kind === 'Function') {
-      const fnShape = state.env.getFunctionSignature(arg.identifier.type);
-      if (fnShape != null) {
-        return (
-          !fnShape.positionalParams.some(isKnownMutableEffect) &&
-          (fnShape.restParam == null ||
-            !isKnownMutableEffect(fnShape.restParam))
-        );
-      }
-    }
     const place = arg.kind === 'Identifier' ? arg : arg.place;
-
     const kind = state.kind(place).kind;
     switch (kind) {
+      case ValueKind.Global:
       case ValueKind.Primitive:
       case ValueKind.Frozen: {
         /*
@@ -1952,10 +2036,6 @@ function areArgumentsImmutableAndNonMutating(
         break;
       }
       default: {
-        /**
-         * Globals, module locals, and other locally defined functions may
-         * mutate their arguments.
-         */
         return false;
       }
     }
@@ -1977,7 +2057,7 @@ function areArgumentsImmutableAndNonMutating(
   return true;
 }
 
-export function getArgumentEffect(
+function getArgumentEffect(
   signatureEffect: Effect | null,
   arg: Place | SpreadPattern,
 ): Effect {
@@ -1998,128 +2078,9 @@ export function getArgumentEffect(
         });
       }
       // effects[i] is Effect.Capture | Effect.Read | Effect.Store
-      return Effect.ConditionallyMutateIterator;
+      return Effect.ConditionallyMutate;
     }
   } else {
     return Effect.ConditionallyMutate;
   }
 }
-
-function inferCallEffects(
-  state: InferenceState,
-  instr:
-    | TInstruction<CallExpression>
-    | TInstruction<MethodCall>
-    | TInstruction<NewExpression>,
-  freezeActions: Array<FreezeAction>,
-  signature: FunctionSignature | null,
-): void {
-  const instrValue = instr.value;
-  const returnValueKind: AbstractValue =
-    signature !== null
-      ? {
-          kind: signature.returnValueKind,
-          reason: new Set([
-            signature.returnValueReason ?? ValueReason.KnownReturnSignature,
-          ]),
-          context: new Set(),
-        }
-      : {
-          kind: ValueKind.Mutable,
-          reason: new Set([ValueReason.Other]),
-          context: new Set(),
-        };
-
-  if (
-    instrValue.kind === 'MethodCall' &&
-    signature !== null &&
-    signature.mutableOnlyIfOperandsAreMutable &&
-    areArgumentsImmutableAndNonMutating(state, instrValue.args)
-  ) {
-    /*
-     * None of the args are mutable or mutate their params, we can downgrade to
-     * treating as all reads (except that the receiver may be captured)
-     */
-    for (const arg of instrValue.args) {
-      const place = arg.kind === 'Identifier' ? arg : arg.place;
-      state.referenceAndRecordEffects(
-        freezeActions,
-        place,
-        Effect.Read,
-        ValueReason.Other,
-      );
-    }
-    state.referenceAndRecordEffects(
-      freezeActions,
-      instrValue.receiver,
-      Effect.Capture,
-      ValueReason.Other,
-    );
-    state.initialize(instrValue, returnValueKind);
-    state.define(instr.lvalue, instrValue);
-    instr.lvalue.effect =
-      instrValue.receiver.effect === Effect.Capture
-        ? Effect.Store
-        : Effect.ConditionallyMutate;
-    return;
-  }
-
-  const effects =
-    signature !== null ? getFunctionEffects(instrValue, signature) : null;
-  let hasCaptureArgument = false;
-  for (let i = 0; i < instrValue.args.length; i++) {
-    const arg = instrValue.args[i];
-    const place = arg.kind === 'Identifier' ? arg : arg.place;
-    /*
-     * If effects are inferred for an argument, we should fail invalid
-     * mutating effects
-     */
-    state.referenceAndRecordEffects(
-      freezeActions,
-      place,
-      getArgumentEffect(effects != null ? effects[i] : null, arg),
-      ValueReason.Other,
-    );
-    hasCaptureArgument ||= place.effect === Effect.Capture;
-  }
-  const callee =
-    instrValue.kind === 'MethodCall' ? instrValue.receiver : instrValue.callee;
-  if (signature !== null) {
-    state.referenceAndRecordEffects(
-      freezeActions,
-      callee,
-      signature.calleeEffect,
-      ValueReason.Other,
-    );
-  } else {
-    /**
-     * For new expressions, we infer a `read` effect on the Class / Function type
-     * to avoid extending mutable ranges of locally created classes, e.g.
-     * ```js
-     * const MyClass = getClass();
-     * const value = new MyClass(val1, val2)
-     *                   ^ (read)   ^ (conditionally mutate)
-     * ```
-     *
-     * Risks:
-     * Classes / functions created during render could technically capture and
-     * mutate their enclosing scope, which we currently do not detect.
-     */
-
-    state.referenceAndRecordEffects(
-      freezeActions,
-      callee,
-      instrValue.kind === 'NewExpression'
-        ? Effect.Read
-        : Effect.ConditionallyMutate,
-      ValueReason.Other,
-    );
-  }
-  hasCaptureArgument ||= callee.effect === Effect.Capture;
-
-  state.initialize(instrValue, returnValueKind);
-  state.define(instr.lvalue, instrValue);
-  instr.lvalue.effect = hasCaptureArgument
-    ? Effect.Store
-    : Effect.ConditionallyMutate;
-}

compiler/packages/babel-plugin-react-compiler/src/Inference/InlineImmediatelyInvokedFunctionExpressions.ts

@@ -11,16 +11,13 @@ import {
   Environment,
   FunctionExpression,
   GeneratedSource,
-  GotoTerminal,
   GotoVariant,
   HIRFunction,
   IdentifierId,
   InstructionKind,
   LabelTerminal,
   Place,
-  isStatementBlockKind,
   makeInstructionId,
-  mergeConsecutiveBlocks,
   promoteTemporary,
   reversePostorderBlocks,
 } from '../HIR';
@@ -75,10 +72,6 @@ import {retainWhere} from '../Utils/utils';
  * - All return statements in the original function expression are replaced with a
  *    StoreLocal to the temporary we allocated before plus a Goto to the fallthrough
  *    block (code following the CallExpression).
- *
- * Note that if the inliined function has only one return, we avoid the labeled block
- * and fully inline the code. The original return is replaced with an assignmen to the
- * IIFE's call expression lvalue.
  */
 export function inlineImmediatelyInvokedFunctionExpressions(
   fn: HIRFunction,
@@ -97,144 +90,100 @@ export function inlineImmediatelyInvokedFunctionExpressions(
    */
   const queue = Array.from(fn.body.blocks.values());
   queue: for (const block of queue) {
-    /*
-     * We can't handle labels inside expressions yet, so we don't inline IIFEs if they are in an
-     * expression block.
-     */
-    if (isStatementBlockKind(block.kind)) {
-      for (let ii = 0; ii < block.instructions.length; ii++) {
-        const instr = block.instructions[ii]!;
-        switch (instr.value.kind) {
-          case 'FunctionExpression': {
-            if (instr.lvalue.identifier.name === null) {
-              functions.set(instr.lvalue.identifier.id, instr.value);
-            }
-            break;
+    for (let ii = 0; ii < block.instructions.length; ii++) {
+      const instr = block.instructions[ii]!;
+      switch (instr.value.kind) {
+        case 'FunctionExpression': {
+          if (instr.lvalue.identifier.name === null) {
+            functions.set(instr.lvalue.identifier.id, instr.value);
           }
-          case 'CallExpression': {
-            if (instr.value.args.length !== 0) {
-              // We don't support inlining when there are arguments
-              continue;
-            }
-            const body = functions.get(instr.value.callee.identifier.id);
-            if (body === undefined) {
-              // Not invoking a local function expression, can't inline
-              continue;
-            }
-
-            if (
-              body.loweredFunc.func.params.length > 0 ||
-              body.loweredFunc.func.async ||
-              body.loweredFunc.func.generator
-            ) {
-              // Can't inline functions with params, or async/generator functions
-              continue;
-            }
-
-            // We know this function is used for an IIFE and can prune it later
-            inlinedFunctions.add(instr.value.callee.identifier.id);
-
-            // Create a new block which will contain code following the IIFE call
-            const continuationBlockId = fn.env.nextBlockId;
-            const continuationBlock: BasicBlock = {
-              id: continuationBlockId,
-              instructions: block.instructions.slice(ii + 1),
-              kind: block.kind,
-              phis: new Set(),
-              preds: new Set(),
-              terminal: block.terminal,
-            };
-            fn.body.blocks.set(continuationBlockId, continuationBlock);
-
-            /*
-             * Trim the original block to contain instructions up to (but not including)
-             * the IIFE
-             */
-            block.instructions.length = ii;
-
-            if (hasSingleExitReturnTerminal(body.loweredFunc.func)) {
-              block.terminal = {
-                kind: 'goto',
-                block: body.loweredFunc.func.body.entry,
-                id: block.terminal.id,
-                loc: block.terminal.loc,
-                variant: GotoVariant.Break,
-              } as GotoTerminal;
-              for (const block of body.loweredFunc.func.body.blocks.values()) {
-                if (block.terminal.kind === 'return') {
-                  block.instructions.push({
-                    id: makeInstructionId(0),
-                    loc: block.terminal.loc,
-                    lvalue: instr.lvalue,
-                    value: {
-                      kind: 'LoadLocal',
-                      loc: block.terminal.loc,
-                      place: block.terminal.value,
-                    },
-                    effects: null,
-                  });
-                  block.terminal = {
-                    kind: 'goto',
-                    block: continuationBlockId,
-                    id: block.terminal.id,
-                    loc: block.terminal.loc,
-                    variant: GotoVariant.Break,
-                  } as GotoTerminal;
-                }
-              }
-              for (const [id, block] of body.loweredFunc.func.body.blocks) {
-                block.preds.clear();
-                fn.body.blocks.set(id, block);
-              }
-            } else {
-              /*
-               * To account for multiple returns within the lambda, we treat the lambda
-               * as if it were a single labeled statement, and replace all returns with gotos
-               * to the label fallthrough.
-               */
-              const newTerminal: LabelTerminal = {
-                block: body.loweredFunc.func.body.entry,
-                id: makeInstructionId(0),
-                kind: 'label',
-                fallthrough: continuationBlockId,
-                loc: block.terminal.loc,
-              };
-              block.terminal = newTerminal;
-
-              // We store the result in the IIFE temporary
-              const result = instr.lvalue;
-
-              // Declare the IIFE temporary
-              declareTemporary(fn.env, block, result);
-
-              // Promote the temporary with a name as we require this to persist
-              if (result.identifier.name == null) {
-                promoteTemporary(result.identifier);
-              }
-
-              /*
-               * Rewrite blocks from the lambda to replace any `return` with a
-               * store to the result and `goto` the continuation block
-               */
-              for (const [id, block] of body.loweredFunc.func.body.blocks) {
-                block.preds.clear();
-                rewriteBlock(fn.env, block, continuationBlockId, result);
-                fn.body.blocks.set(id, block);
-              }
-            }
-
-            /*
-             * Ensure we visit the continuation block, since there may have been
-             * sequential IIFEs that need to be visited.
-             */
-            queue.push(continuationBlock);
-            continue queue;
+          break;
+        }
+        case 'CallExpression': {
+          if (instr.value.args.length !== 0) {
+            // We don't support inlining when there are arguments
+            continue;
           }
-          default: {
-            for (const place of eachInstructionValueOperand(instr.value)) {
-              // Any other use of a function expression means it isn't an IIFE
-              functions.delete(place.identifier.id);
-            }
+          const body = functions.get(instr.value.callee.identifier.id);
+          if (body === undefined) {
+            // Not invoking a local function expression, can't inline
+            continue;
+          }
+
+          if (
+            body.loweredFunc.func.params.length > 0 ||
+            body.loweredFunc.func.async ||
+            body.loweredFunc.func.generator
+          ) {
+            // Can't inline functions with params, or async/generator functions
+            continue;
+          }
+
+          // We know this function is used for an IIFE and can prune it later
+          inlinedFunctions.add(instr.value.callee.identifier.id);
+
+          // Create a new block which will contain code following the IIFE call
+          const continuationBlockId = fn.env.nextBlockId;
+          const continuationBlock: BasicBlock = {
+            id: continuationBlockId,
+            instructions: block.instructions.slice(ii + 1),
+            kind: block.kind,
+            phis: new Set(),
+            preds: new Set(),
+            terminal: block.terminal,
+          };
+          fn.body.blocks.set(continuationBlockId, continuationBlock);
+
+          /*
+           * Trim the original block to contain instructions up to (but not including)
+           * the IIFE
+           */
+          block.instructions.length = ii;
+
+          /*
+           * To account for complex control flow within the lambda, we treat the lambda
+           * as if it were a single labeled statement, and replace all returns with gotos
+           * to the label fallthrough.
+           */
+          const newTerminal: LabelTerminal = {
+            block: body.loweredFunc.func.body.entry,
+            id: makeInstructionId(0),
+            kind: 'label',
+            fallthrough: continuationBlockId,
+            loc: block.terminal.loc,
+          };
+          block.terminal = newTerminal;
+
+          // We store the result in the IIFE temporary
+          const result = instr.lvalue;
+
+          // Declare the IIFE temporary
+          declareTemporary(fn.env, block, result);
+
+          // Promote the temporary with a name as we require this to persist
+          promoteTemporary(result.identifier);
+
+          /*
+           * Rewrite blocks from the lambda to replace any `return` with a
+           * store to the result and `goto` the continuation block
+           */
+          for (const [id, block] of body.loweredFunc.func.body.blocks) {
+            block.preds.clear();
+            rewriteBlock(fn.env, block, continuationBlockId, result);
+            fn.body.blocks.set(id, block);
+          }
+
+          /*
+           * Ensure we visit the continuation block, since there may have been
+           * sequential IIFEs that need to be visited.
+           */
+          queue.push(continuationBlock);
+          continue queue;
+        }
+        default: {
+          for (const place of eachInstructionValueOperand(instr.value)) {
+            // Any other use of a function expression means it isn't an IIFE
+            functions.delete(place.identifier.id);
           }
         }
       }
@@ -243,7 +192,7 @@ export function inlineImmediatelyInvokedFunctionExpressions(
 
   if (inlinedFunctions.size !== 0) {
     // Remove instructions that define lambdas which we inlined
-    for (const block of fn.body.blocks.values()) {
+    for (const [, block] of fn.body.blocks) {
       retainWhere(
         block.instructions,
         instr => !inlinedFunctions.has(instr.lvalue.identifier.id),
@@ -257,25 +206,9 @@ export function inlineImmediatelyInvokedFunctionExpressions(
     reversePostorderBlocks(fn.body);
     markInstructionIds(fn.body);
     markPredecessors(fn.body);
-    mergeConsecutiveBlocks(fn);
   }
 }
 
-/**
- * Returns true if the function has a single exit terminal (throw/return) which is a return
- */
-function hasSingleExitReturnTerminal(fn: HIRFunction): boolean {
-  let hasReturn = false;
-  let exitCount = 0;
-  for (const [, block] of fn.body.blocks) {
-    if (block.terminal.kind === 'return' || block.terminal.kind === 'throw') {
-      hasReturn ||= block.terminal.kind === 'return';
-      exitCount++;
-    }
-  }
-  return exitCount === 1 && hasReturn;
-}
-
 /*
  * Rewrites the block so that all `return` terminals are replaced:
  * * Add a StoreLocal <returnValue> = <terminal.value>
@@ -302,7 +235,6 @@ function rewriteBlock(
       type: null,
       loc: terminal.loc,
     },
-    effects: null,
   });
   block.terminal = {
     kind: 'goto',
@@ -331,6 +263,5 @@ function declareTemporary(
       type: null,
       loc: result.loc,
     },
-    effects: null,
   });
 }

compiler/packages/babel-plugin-react-compiler/src/Inference/MUTABILITY_ALIASING_MODEL.md

@@ -1,559 +0,0 @@
-# The Mutability & Aliasing Model
-
-This document describes the new (as of June 2025) mutability and aliasing model powering React Compiler. The mutability and aliasing system is a conceptual subcomponent whose primary role is to determine minimal sets of values that mutate together, and the range of instructions over which those mutations occur. These minimal sets of values that mutate together, and the corresponding instructions doing those mutations, are ultimately grouped into reactive scopes, which then translate into memoization blocks in the output (after substantial additional processing described in the comments of those passes).
-
-To build an intuition, consider the following example:
-
-```js
-function Component() {
-    // a is created and mutated over the course of these two instructions:
-    const a = {};
-    mutate(a);
-
-    // b and c are created and mutated together — mutate might modify b via c
-    const b = {};
-    const c = {b};
-    mutate(c);
-
-    // does not modify a/b/c
-    return <Foo a={a} c={c} />
-}
-```
-
-The goal of mutability and aliasing inference is to understand the set of instructions that create/modify a, b, and c.
-
-In code, the mutability and aliasing model is compromised of the following phases:
-
-* `InferMutationAliasingEffects`. Infers a set of mutation and aliasing effects for each instruction. The approach is to generate a set of candidate effects based purely on the semantics of each instruction and the types of the operands, then use abstract interpretation to determine the actual effects (or errros) that would apply. For example, an instruction that by default has a Capture effect might downgrade to an ImmutableCapture effect if the value is known to be frozen.
-* `InferMutationAliasingRanges`. Infers a mutable range (start:end instruction ids) for each value in the program, and annotates each Place with its effect type for usage in later passes. This builds a graph of data flow through the program over time in order to understand which mutations effect which values.
-* `InferReactiveScopeVariables`. Given the per-Place effects, determines disjoint sets of values that mutate together and assigns all identifiers in each set to a unique scope, and updates the range to include the ranges of all constituent values.
-
-Finally, `AnalyzeFunctions` needs to understand the mutation and aliasing semantics of nested FunctionExpression and ObjectMethod values. `AnalyzeFunctions` calls `InferFunctionExpressionAliasingEffectsSignature` to determine the publicly observable set of mutation/aliasing effects for nested functions.
-
-## Mutation and Aliasing Effects
-
-The inference model is based on a set of "effects" that describe subtle aspects of mutation, aliasing, and other changes to the state of values over time
-
-### Creation Effects
-
-#### Create
-
-```js
-{
-    kind: 'Create';
-    into: Place;
-    value: ValueKind;
-    reason: ValueReason;
-}
-```
-
-Describes the creation of a new value with the given kind, and reason for having that kind. For example, `x = 10` might have an effect like `Create x = ValueKind.Primitive [ValueReason.Other]`.
-
-#### CreateFunction
-
-```js
-{
-    kind: 'CreateFunction';
-    captures: Array<Place>;
-    function: FunctionExpression | ObjectMethod;
-    into: Place;
-}
-```
-
-Describes the creation of new function value, capturing the given set of mutable values. CreateFunction is used to specifically track function types so that we can precisely model calls to those functions with `Apply`.
-
-#### Apply
-
-```js
-{
-    kind: 'Apply';
-    receiver: Place;
-    function: Place; // same as receiver for function calls
-    mutatesFunction: boolean; // indicates if this is a type that we consdier to mutate the function itself by default
-    args: Array<Place | SpreadPattern | Hole>;
-    into: Place; // where result is stored
-    signature: FunctionSignature | null;
-}
-```
-
-Describes the potential creation of a value by calling a function. This models `new`, function calls, and method calls. The inference algorithm uses the most precise signature it can determine:
-
-* If the function is a locally created function expression, we use a signature inferred from the behavior of that function to interpret the effects of calling it with the given arguments.
-* Else if the function has a known aliasing signature (new style precise effects signature), we apply the arguments to that signature to get a precise set of effects.
-* Else if the function has a legacy style signature (with per-param effects) we convert the legacy per-Place effects into aliasing effects (described in this doc) and apply those.
-* Else fall back to inferring a generic set of effects.
-
-The generic fallback is to assume:
-- The return value may alias any of the arguments (Alias param -> return)
-- Any arguments *may* be transitively mutated (MutateTransitiveConditionally param)
-- Any argument may be captured into any other argument (Capture paramN -> paramM for all N,M where N != M)
-
-### Aliasing Effects
-
-These effects describe data-flow only, separately from mutation or other state-changing semantics.
-
-#### Assign
-
-```js
-{
-    kind: 'Assign';
-    from: Place;
-    into: Place;
-}
-```
-
-Describes an `x = y` assignment, where the receiving (into) value is overwritten with a new (from) value. After this effect, any previous assignments/aliases to the receiving value are dropped. Note that `Alias` initializes the receiving value.
-
-> TODO: InferMutationAliasingRanges may not fully reset aliases on encountering this effect
-
-#### Alias
-
-```js
-{
-    kind: 'Alias';
-    from: Place;
-    into: Place;
-}
-```
-
-Describes that an assignment _may_ occur, but that the possible assignment is non-exclusive. The canonical use-case for `Alias` is a function that may return more than one of its arguments, such as `(x, y, z) => x ? y : z`. Here, the result of this function may be `y` or `z`, but neither one overwrites the other. Note that `Alias` does _not_ initialize the receiving value: it should always be paired with an effect to create the receiving value.
-
-#### Capture
-
-```js
-{
-    kind: 'Capture';
-    from: Place;
-    into: Place;
-}
-```
-
-Describes that a reference to one variable (from) is stored within another value (into). Examples include:
-- An array expression captures the items of the array (`array = [capturedValue]`)
-- Array.prototype.push captures the pushed values into the array (`array.push(capturedValue)`)
-- Property assignment captures the value onto the object (`object.property = capturedValue`)
-
-#### CreateFrom
-
-```js
-{
-    kind: 'CreateFrom';
-    from: Place;
-    into: Place;
-}
-```
-
-This is somewhat the inverse of `Capture`. The `CreateFrom` effect describes that a variable is initialized by extracting _part_ of another value, without taking a direct alias to the full other value. Examples include:
-
-- Indexing into an array (`createdFrom = array[0]`)
-- Reading an object property (`createdFrom = object.property`)
-- Getting a Map key (`createdFrom = map.get(key)`)
-
-#### ImmutableCapture
-
-Describes immutable data flow from one value to another. This is not currently used for anything, but is intended to eventually power a more sophisticated escape analysis.
-
-### MaybeAlias
-
-Describes potential data flow that the compiler knows may occur behind a function call, but cannot be sure about. For example, `foo(x)` _may_ be the identity function and return `x`, or `cond(a, b, c)` may conditionally return `b` or `c` depending on the value of `a`, but those functions could just as easily return new mutable values and not capture any information from their arguments. MaybeAlias represents that we have to consider the potential for data flow when deciding mutable ranges, but should be conservative about reporting errors. For example, `foo(someFrozenValue).property = true` should not error since we don't know for certain that foo returns its input.
-
-### State-Changing Effects
-
-The following effects describe state changes to specific values, not data flow. In many cases, JavaScript semantics will involve a combination of both data-flow effects *and* state-change effects. For example, `object.property = value` has data flow (`Capture object <- value`) and mutation (`Mutate object`).
-
-#### Freeze
-
-```js
-{
-    kind: 'Freeze',
-    // The reference being frozen
-    value: Place;
-    // The reason the value is frozen (passed to a hook, passed to jsx, etc)
-    reason: ValueReason;
-}
-```
-
-Once a reference to a value has been passed to React, that value is generally not safe to mutate further. This is not a strictly required property of React, but is a natural consequence of making components and hooks composable without leaking implementation details. Concretely, once a value has been passed as a JSX prop, passed as argument to a hook, or returned from a hook, it must be assumed that the other "side" — receiver of the prop/argument/return value — will use that value as an input to an effect or memoization unit. Mutating that value (instead of creating a new value) will fail to cause the consuming computation to update:
-
-```js
-// INVALID DO NOT DO THIS
-function Component(props) {
-    const array = useArray(props.value);
-    // OOPS! this value is memoized, the array won't get re-created
-    // when `props.value` changes, so we might just keep pushing new
-    // values to the same array on every render!
-    array.push(props.otherValue);
-}
-
-function useArray(a) {
-    return useMemo(() => [a], [a]);
-}
-```
-
-The **Freeze** effect accepts a variable reference and a reason that the value is being frozen. Note: _freeze only applies to the reference, not the underlying value_. Our inference is conservative, and assumes that there may still be other references to the same underlying value which are mutated later. For example:
-
-```js
-const x = {};
-const y = [];
-x.y = y;
-freeze(y); // y _reference_ is frozen
-x.y.push(props.value); // but y is still considered mutable bc of this
-```
-
-#### Mutate (and MutateConditionally)
-
-```js
-{
-    kind: 'Mutate';
-    value: Place;
-}
-```
-
-Mutate indicates that a value is mutated, without modifying any of the values that it may transitively have captured. Canonical examples include:
-
-- Pushing an item onto an array modifies the array, but does not modify any items stored _within_ the array (unless the array has a reference to itself!)
-- Assigning a value to an object property modifies the object, but not any values stored in the object's other properties.
-
-This helps explain the distinction between Assign/Alias and Capture: Mutate only affects assign/alias but not captures.
-
-`MutateConditionally` is an alternative in which the mutation _may_ happen depending on the type of the value. The conditional variant is not generally used and included for completeness.
-
-
-
-#### MutateTransitiveConditionally (and MutateTransitive)
-
-`MutateTransitiveConditionally` represents an operation that may mutate _any_ aspect of a value, including reaching arbitrarily deep into nested values to mutate them. This is the default semantic for unknown functions — we have no idea what they do, so we assume that they are idempotent but may mutate any aspect of the mutable values that are passed to them.
-
-There is also `MutateTransitive` for completeness, but this is not generally used.
-
-### Side Effects
-
-Finally, there are a few effects that describe error, or potential error, conditions:
-
-- `MutateFrozen` is always an error, because it indicates known mutation of a value that should not be mutated.
-- `MutateGlobal` indicates known mutation of a global value, which is not safe during render. This effect is an error if reachable during render, but allowed if only reachable via an event handler or useEffect.
-- `Impure` indicates calling some other logic that is impure/side-effecting. This is an error if reachable during render, but allowed if only reachable via an event handler or useEffect.
-  - TODO: we could probably merge this and MutateGlobal
-- `Render` indicates a value that is not mutated, but is known to be called during render. It's used for a few particular places like JSX tags and JSX children, which we assume are accessed during render (while other props may be event handlers etc). This helps to detect more MutateGlobal/Impure effects and reject more invalid programs.
-
-
-## Rules
-
-### Mutation of Alias Mutates the Source Value
-
-```
-Alias a <- b
-Mutate a
-=>
-Mutate b
-```
-
-Example:
-
-```js
-const a = maybeIdentity(b); // Alias a <- b
-a.property = value; // a could be b, so this mutates b
-```
-
-### Mutation of Assignment Mutates the Source Value
-
-```
-Assign a <- b
-Mutate a
-=>
-Mutate b
-```
-
-Example:
-
-```js
-const a = b;
-a.property = value // a _is_ b, this mutates b
-```
-
-### Mutation of CreateFrom Mutates the Source Value
-
-```
-CreateFrom a <- b
-Mutate a
-=>
-Mutate b
-```
-
-Example:
-
-```js
-const a = b[index];
-a.property = value // the contents of b are transitively mutated
-```
-
-
-### Mutation of Capture Does *Not* Mutate the Source Value
-
-```
-Capture a <- b
-Mutate a
-!=>
-~Mutate b~
-```
-
-Example:
-
-```js
-const a = {};
-a.b = b;
-a.property = value; // mutates a, not b
-```
-
-### Mutation of Source Affects Alias, Assignment, CreateFrom, and Capture
-
-```
-Alias a <- b OR Assign a <- b OR CreateFrom a <- b OR Capture a <- b
-Mutate b
-=>
-Mutate a
-```
-
-A derived value changes when it's source value is mutated.
-
-Example:
-
-```js
-const x = {};
-const y = [x];
-x.y = true; // this changes the value within `y` ie mutates y
-```
-
-
-### TransitiveMutation of Alias, Assignment, CreateFrom, or Capture Mutates the Source
-
-```
-Alias a <- b OR Assign a <- b OR CreateFrom a <- b OR Capture a <- b
-MutateTransitive a
-=>
-MutateTransitive b
-```
-
-Remember, the intuition for a transitive mutation is that it's something that could traverse arbitrarily deep into an object and mutate whatever it finds. Imagine something that recurses into every nested object/array and sets `.field = value`. Given a function `mutate()` that does this, then:
-
-```js
-const a = b; // assign
-mutate(a); // clearly can transitively mutate b
-
-const a = maybeIdentity(b); // alias
-mutate(a); // clearly can transitively mutate b
-
-const a = b[index]; // createfrom
-mutate(a); // clearly can transitively mutate b
-
-const a = {};
-a.b = b; // capture
-mutate(a); // can transitively mutate b
-```
-
-### MaybeAlias makes mutation conditional
-
-Because we don't know for certain that the aliasing occurs, we consider the mutation conditional against the source.
-
-```
-MaybeAlias a <- b
-Mutate a
-=>
-MutateConditional b
-```
-
-### Freeze Does Not Freeze the Value
-
-Freeze does not freeze the value itself:
-
-```
-Create x
-Assign y <- x OR Alias y <- x OR CreateFrom y <- x OR Capture y <- x
-Freeze y
-!=>
-~Freeze x~
-```
-
-This means that subsequent mutations of the original value are valid:
-
-```
-Create x
-Assign y <- x OR Alias y <- x OR CreateFrom y <- x OR Capture y <- x
-Freeze y
-Mutate x
-=>
-Mutate x (mutation is ok)
-```
-
-As well as mutations through other assignments/aliases/captures/createfroms of the original value:
-
-```
-Create x
-Assign y <- x OR Alias y <- x OR CreateFrom y <- x OR Capture y <- x
-Freeze y
-Alias z <- x OR Capture z <- x OR CreateFrom z <- x OR Assign z <- x
-Mutate z
-=>
-Mutate x (mutation is ok)
-```
-
-### Freeze Freezes The Reference 
-
-Although freeze doesn't freeze the value, it does affect the reference. The reference cannot be used to mutate.
-
-Conditional mutations of the reference are no-ops:
-
-```
-Create x
-Assign y <- x OR Alias y <- x OR CreateFrom y <- x OR Capture y <- x
-Freeze y
-MutateConditional y
-=>
-(no mutation)
-```
-
-And known mutations of the reference are errors:
-
-```
-Create x
-Assign y <- x OR Alias y <- x OR CreateFrom y <- x OR Capture y <- x
-Freeze y
-MutateConditional y
-=>
-MutateFrozen y error=...
-```
-
-### Corollary: Transitivity of Assign/Alias/CreateFrom/Capture
-
-A key part of the inference model is inferring a signature for function expressions. The signature is a minimal set of effects that describes the publicly observable behavior of the function. This can include "global" effects like side effects (MutateGlobal/Impure) as well as mutations/aliasing of parameters and free variables.
-
-In order to determine the aliasing of params and free variables into each other and/or the return value, we may encounter chains of assign, alias, createfrom, and capture effects. For example:
-
-```js
-const f = (x) => {
-    const y = [x];  // capture y <- x
-    const z = y[0]; // createfrom z <- y
-    return z;     // assign return <- z
-}
-// <Effect> return <- x
-```
-
-In this example we can see that there should be some effect on `f` that tracks the flow of data from `x` into the return value. The key constraint is preserving the semantics around how local/transitive mutations of the destination would affect the source.
-
-#### Each of the effects is transitive with itself
-
-```
-Assign b <- a
-Assign c <- b
-=>
-Assign c <- a
-```
-
-```
-Alias b <- a
-Alias c <- b
-=>
-Alias c <- a
-```
-
-```
-CreateFrom b <- a
-CreateFrom c <- b
-=>
-CreateFrom c <- a
-```
-
-```
-Capture b <- a
-Capture c <- b
-=>
-Capture c <- a
-```
-
-#### Alias > Assign
-
-```
-Assign b <- a
-Alias c <- b
-=>
-Alias c <- a
-```
-
-```
-Alias b <- a
-Assign c <- b
-=>
-Alias c <- a
-```
-
-### CreateFrom > Assign/Alias
-
-Intuition: 
-
-```
-CreateFrom b <- a
-Alias c <- b OR Assign c <- b
-=>
-CreateFrom c <- a
-```
-
-```
-Alias b <- a OR Assign b <- a
-CreateFrom c <- b
-=>
-CreateFrom c <- a
-```
-
-### Capture > Assign/Alias
-
-Intuition: capturing means that a local mutation of the destination will not affect the source, so we preserve the capture.
-
-```
-Capture b <- a
-Alias c <- b OR Assign c <- b
-=>
-Capture c <- a
-```
-
-```
-Alias b <- a OR Assign b <- a
-Capture c <- b
-=>
-Capture c <- a
-```
-
-### Capture And CreateFrom
-
-Intuition: these effects are inverses of each other (capturing into an object, extracting from an object). The result is based on the order of operations:
-
-Capture then CreatFrom is equivalent to Alias: we have to assume that the result _is_ the original value and that a local mutation of the result could mutate the original.
-
-```js
-const b = [a]; // capture
-const c = b[0]; // createfrom
-mutate(c); // this clearly can mutate a, so the result must be one of Assign/Alias/CreateFrom 
-```
-
-We use Alias as the return type because the mutability kind of the result is not derived from the source value (there's a fresh object in between due to the capture), so the full set of effects in practice would be a Create+Alias.
-
-```
-Capture b <- a
-CreateFrom c <- b
-=>
-Alias c <- a
-```
-
-Meanwhile the opposite direction preserves the capture, because the result is not the same as the source:
-
-```js
-const b = a[0]; // createfrom
-const c = [b]; // capture
-mutate(c); // does not mutate a, so the result must be Capture
-```
-
-```
-CreateFrom b <- a
-Capture c <- b
-=>
-Capture c <- a
-```

compiler/packages/babel-plugin-react-compiler/src/Optimization/ConstantPropagation.ts

@@ -327,23 +327,6 @@ function evaluateInstruction(
           }
           return null;
         }
-        case '-': {
-          const operand = read(constants, value.value);
-          if (
-            operand !== null &&
-            operand.kind === 'Primitive' &&
-            typeof operand.value === 'number'
-          ) {
-            const result: Primitive = {
-              kind: 'Primitive',
-              value: operand.value * -1,
-              loc: value.loc,
-            };
-            instr.value = result;
-            return result;
-          }
-          return null;
-        }
         default:
           return null;
       }
@@ -509,73 +492,6 @@ function evaluateInstruction(
       }
       return null;
     }
-    case 'TemplateLiteral': {
-      if (value.subexprs.length === 0) {
-        const result: InstructionValue = {
-          kind: 'Primitive',
-          value: value.quasis.map(q => q.cooked).join(''),
-          loc: value.loc,
-        };
-        instr.value = result;
-        return result;
-      }
-
-      if (value.subexprs.length !== value.quasis.length - 1) {
-        return null;
-      }
-
-      if (value.quasis.some(q => q.cooked === undefined)) {
-        return null;
-      }
-
-      let quasiIndex = 0;
-      let resultString = value.quasis[quasiIndex].cooked as string;
-      ++quasiIndex;
-
-      for (const subExpr of value.subexprs) {
-        const subExprValue = read(constants, subExpr);
-        if (!subExprValue || subExprValue.kind !== 'Primitive') {
-          return null;
-        }
-
-        const expressionValue = subExprValue.value;
-        if (
-          typeof expressionValue !== 'number' &&
-          typeof expressionValue !== 'string' &&
-          typeof expressionValue !== 'boolean' &&
-          !(typeof expressionValue === 'object' && expressionValue === null)
-        ) {
-          // value is not supported (function, object) or invalid (symbol), or something else
-          return null;
-        }
-
-        const suffix = value.quasis[quasiIndex].cooked;
-        ++quasiIndex;
-
-        if (suffix === undefined) {
-          return null;
-        }
-
-        /*
-         * Spec states that concat calls ToString(argument) internally on its parameters
-         * -> we don't have to implement ToString(argument) ourselves and just use the engine implementation
-         * Refs:
-         *  - https://tc39.es/ecma262/2024/#sec-tostring
-         *  - https://tc39.es/ecma262/2024/#sec-string.prototype.concat
-         *  - https://tc39.es/ecma262/2024/#sec-template-literals-runtime-semantics-evaluation
-         */
-        resultString = resultString.concat(expressionValue as string, suffix);
-      }
-
-      const result: InstructionValue = {
-        kind: 'Primitive',
-        value: resultString,
-        loc: value.loc,
-      };
-
-      instr.value = result;
-      return result;
-    }
     case 'LoadLocal': {
       const placeValue = read(constants, value.place);
       if (placeValue !== null) {

compiler/packages/babel-plugin-react-compiler/src/Optimization/InlineJsxTransform.ts

@@ -151,7 +151,6 @@ export function inlineJsxTransform(
               type: null,
               loc: instr.value.loc,
             },
-            effects: null,
             loc: instr.loc,
           };
           currentBlockInstructions.push(varInstruction);
@@ -168,7 +167,6 @@ export function inlineJsxTransform(
               },
               loc: instr.value.loc,
             },
-            effects: null,
             loc: instr.loc,
           };
           currentBlockInstructions.push(devGlobalInstruction);
@@ -222,7 +220,6 @@ export function inlineJsxTransform(
               type: null,
               loc: instr.value.loc,
             },
-            effects: null,
             loc: instr.loc,
           };
           thenBlockInstructions.push(reassignElseInstruction);
@@ -295,7 +292,6 @@ export function inlineJsxTransform(
               ],
               loc: instr.value.loc,
             },
-            effects: null,
             loc: instr.loc,
           };
           elseBlockInstructions.push(reactElementInstruction);
@@ -313,7 +309,6 @@ export function inlineJsxTransform(
               type: null,
               loc: instr.value.loc,
             },
-            effects: null,
             loc: instr.loc,
           };
           elseBlockInstructions.push(reassignConditionalInstruction);
@@ -441,7 +436,6 @@ function createSymbolProperty(
       binding: {kind: 'Global', name: 'Symbol'},
       loc: instr.value.loc,
     },
-    effects: null,
     loc: instr.loc,
   };
   nextInstructions.push(symbolInstruction);
@@ -456,7 +450,6 @@ function createSymbolProperty(
       property: makePropertyLiteral('for'),
       loc: instr.value.loc,
     },
-    effects: null,
     loc: instr.loc,
   };
   nextInstructions.push(symbolForInstruction);
@@ -470,7 +463,6 @@ function createSymbolProperty(
       value: symbolName,
       loc: instr.value.loc,
     },
-    effects: null,
     loc: instr.loc,
   };
   nextInstructions.push(symbolValueInstruction);
@@ -486,7 +478,6 @@ function createSymbolProperty(
       args: [symbolValueInstruction.lvalue],
       loc: instr.value.loc,
     },
-    effects: null,
     loc: instr.loc,
   };
   const $$typeofProperty: ObjectProperty = {
@@ -517,7 +508,6 @@ function createTagProperty(
           value: componentTag.name,
           loc: instr.value.loc,
         },
-        effects: null,
         loc: instr.loc,
       };
       tagProperty = {
@@ -644,7 +634,6 @@ function createPropsProperties(
           elements: [...children],
           loc: instr.value.loc,
         },
-        effects: null,
         loc: instr.loc,
       };
       nextInstructions.push(childrenPropInstruction);
@@ -668,7 +657,6 @@ function createPropsProperties(
         value: null,
         loc: instr.value.loc,
       },
-      effects: null,
       loc: instr.loc,
     };
     refProperty = {
@@ -690,7 +678,6 @@ function createPropsProperties(
         value: null,
         loc: instr.value.loc,
       },
-      effects: null,
       loc: instr.loc,
     };
     keyProperty = {
@@ -724,7 +711,6 @@ function createPropsProperties(
         properties: props,
         loc: instr.value.loc,
       },
-      effects: null,
       loc: instr.loc,
     };
     propsProperty = {

compiler/packages/babel-plugin-react-compiler/src/Optimization/LowerContextAccess.ts

@@ -18,13 +18,13 @@ import {
   Instruction,
   LoadGlobal,
   LoadLocal,
-  NonLocalImportSpecifier,
   Place,
   PropertyLoad,
   isUseContextHookType,
   makeBlockId,
   makeInstructionId,
   makePropertyLiteral,
+  makeType,
   markInstructionIds,
   promoteTemporary,
   reversePostorderBlocks,
@@ -35,7 +35,7 @@ import {inferTypes} from '../TypeInference';
 
 export function lowerContextAccess(
   fn: HIRFunction,
-  loweredContextCalleeConfig: ExternalFunction,
+  loweredContextCallee: ExternalFunction,
 ): void {
   const contextAccess: Map<IdentifierId, CallExpression> = new Map();
   const contextKeys: Map<IdentifierId, Array<string>> = new Map();
@@ -79,8 +79,6 @@ export function lowerContextAccess(
     }
   }
 
-  let importLoweredContextCallee: NonLocalImportSpecifier | null = null;
-
   if (contextAccess.size > 0 && contextKeys.size > 0) {
     for (const [, block] of fn.body.blocks) {
       let nextInstructions: Array<Instruction> | null = null;
@@ -93,13 +91,9 @@ export function lowerContextAccess(
           isUseContextHookType(value.callee.identifier) &&
           contextKeys.has(lvalue.identifier.id)
         ) {
-          importLoweredContextCallee ??=
-            fn.env.programContext.addImportSpecifier(
-              loweredContextCalleeConfig,
-            );
           const loweredContextCalleeInstr = emitLoadLoweredContextCallee(
             fn.env,
-            importLoweredContextCallee,
+            loweredContextCallee,
           );
 
           if (nextInstructions === null) {
@@ -128,16 +122,21 @@ export function lowerContextAccess(
     }
     markInstructionIds(fn.body);
     inferTypes(fn);
+    fn.env.hasLoweredContextAccess = true;
   }
 }
 
 function emitLoadLoweredContextCallee(
   env: Environment,
-  importedLowerContextCallee: NonLocalImportSpecifier,
+  loweredContextCallee: ExternalFunction,
 ): Instruction {
   const loadGlobal: LoadGlobal = {
     kind: 'LoadGlobal',
-    binding: {...importedLowerContextCallee},
+    binding: {
+      kind: 'ImportNamespace',
+      module: loweredContextCallee.source,
+      name: loweredContextCallee.importSpecifierName,
+    },
     loc: GeneratedSource,
   };
 
@@ -145,7 +144,6 @@ function emitLoadLoweredContextCallee(
     id: makeInstructionId(0),
     loc: GeneratedSource,
     lvalue: createTemporaryPlace(env, GeneratedSource),
-    effects: null,
     value: loadGlobal,
   };
 }
@@ -192,7 +190,6 @@ function emitPropertyLoad(
     lvalue: object,
     value: loadObj,
     id: makeInstructionId(0),
-    effects: null,
     loc: GeneratedSource,
   };
 
@@ -207,7 +204,6 @@ function emitPropertyLoad(
     lvalue: element,
     value: loadProp,
     id: makeInstructionId(0),
-    effects: null,
     loc: GeneratedSource,
   };
   return {
@@ -237,10 +233,8 @@ function emitSelectorFn(env: Environment, keys: Array<string>): Instruction {
     terminal: {
       id: makeInstructionId(0),
       kind: 'return',
-      returnVariant: 'Explicit',
       loc: GeneratedSource,
       value: arrayInstr.lvalue,
-      effects: null,
     },
     preds: new Set(),
     phis: new Set(),
@@ -253,7 +247,7 @@ function emitSelectorFn(env: Environment, keys: Array<string>): Instruction {
     env,
     params: [obj],
     returnTypeAnnotation: null,
-    returns: createTemporaryPlace(env, GeneratedSource),
+    returnType: makeType(),
     context: [],
     effects: null,
     body: {
@@ -282,7 +276,6 @@ function emitSelectorFn(env: Environment, keys: Array<string>): Instruction {
       loc: GeneratedSource,
     },
     lvalue: createTemporaryPlace(env, GeneratedSource),
-    effects: null,
     loc: GeneratedSource,
   };
   return fnInstr;
@@ -299,7 +292,6 @@ function emitArrayInstr(elements: Array<Place>, env: Environment): Instruction {
     id: makeInstructionId(0),
     value: array,
     lvalue: arrayLvalue,
-    effects: null,
     loc: GeneratedSource,
   };
   return arrayInstr;