[compiler] Adjustments to exhaustive deps messages, disable the lint rule

Similar to ValidateHookUsage, we implement this check in the compiler for safety but (for now) continue to rely on the existing rule for actually reporting errors to users.

.eslintrc.js

@@ -331,7 +331,6 @@ module.exports = {
         'packages/react-server-dom-turbopack/**/*.js',
         'packages/react-server-dom-parcel/**/*.js',
         'packages/react-server-dom-fb/**/*.js',
-        'packages/react-server-dom-unbundled/**/*.js',
         'packages/react-test-renderer/**/*.js',
         'packages/react-debug-tools/**/*.js',
         'packages/react-devtools-extensions/**/*.js',
@@ -593,7 +592,6 @@ module.exports = {
     mixin$Animatable: 'readonly',
     MouseEventHandler: 'readonly',
     NavigateEvent: 'readonly',
-    Partial: 'readonly',
     PerformanceMeasureOptions: 'readonly',
     PropagationPhases: 'readonly',
     PropertyDescriptor: 'readonly',
@@ -636,7 +634,6 @@ module.exports = {
     FocusOptions: 'readonly',
     OptionalEffectTiming: 'readonly',
 
-    __REACT_ROOT_PATH_TEST__: 'readonly',
     spyOnDev: 'readonly',
     spyOnDevAndProd: 'readonly',
     spyOnProd: 'readonly',

.github/workflows/runtime_build_and_test.yml

@@ -3,10 +3,6 @@ name: (Runtime) Build and Test
 on:
   push:
     branches: [main]
-    tags:
-      # To get CI for backport releases.
-      # This will duplicate CI for releases from main which is acceptable
-      - "v*"
   pull_request:
     paths-ignore:
       - compiler/**
@@ -45,7 +41,7 @@ jobs:
         with:
           path: |
             **/node_modules
-          key: runtime-node_modules-v7-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
+          key: runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
           lookup-only: true
       - uses: actions/setup-node@v4
         if: steps.node_modules.outputs.cache-hit != 'true'
@@ -59,8 +55,10 @@ jobs:
         with:
           path: |
             **/node_modules
-          key: runtime-node_modules-v7-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
-          # Don't use restore-keys here. Otherwise the cache grows indefinitely.
+          key: runtime-node_modules-v6-${{ 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
@@ -69,7 +67,7 @@ jobs:
         with:
           path: |
             **/node_modules
-          key: runtime-node_modules-v7-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
+          key: runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
 
   runtime_compiler_node_modules_cache:
     name: Cache Runtime, Compiler node_modules
@@ -84,7 +82,7 @@ jobs:
         with:
           path: |
             **/node_modules
-          key: runtime-and-compiler-node_modules-v7-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock', 'compiler/yarn.lock') }}
+          key: runtime-and-compiler-node_modules-v6-${{ 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'
@@ -100,8 +98,10 @@ jobs:
         with:
           path: |
             **/node_modules
-          key: runtime-and-compiler-node_modules-v7-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock', 'compiler/yarn.lock') }}
-          # Don't use restore-keys here. Otherwise the cache grows indefinitely.
+          key: runtime-and-compiler-node_modules-v6-${{ 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
@@ -112,7 +112,7 @@ jobs:
         with:
           path: |
             **/node_modules
-          key: runtime-and-compiler-node_modules-v7-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock', 'compiler/yarn.lock') }}
+          key: runtime-and-compiler-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock', 'compiler/yarn.lock') }}
 
   # ----- FLOW -----
   discover_flow_inline_configs:
@@ -154,8 +154,10 @@ jobs:
         with:
           path: |
             **/node_modules
-          key: runtime-node_modules-v7-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
-          # Don't use restore-keys here. Otherwise the cache grows indefinitely.
+          key: runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
+          restore-keys: |
+            runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-
+            runtime-node_modules-v6-
       - name: Ensure clean build directory
         run: rm -rf build
       - run: yarn install --frozen-lockfile
@@ -182,8 +184,10 @@ jobs:
         with:
           path: |
             **/node_modules
-          key: runtime-node_modules-v7-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
-          # Don't use restore-keys here. Otherwise the cache grows indefinitely.
+          key: runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
+          restore-keys: |
+            runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-
+            runtime-node_modules-v6-
       - name: Ensure clean build directory
         run: rm -rf build
       - run: yarn install --frozen-lockfile
@@ -212,7 +216,7 @@ jobs:
         with:
           path: |
             **/node_modules
-          key: runtime-node_modules-v7-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
+          key: runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
       - name: Ensure clean build directory
         run: rm -rf build
       - run: yarn install --frozen-lockfile
@@ -270,15 +274,16 @@ jobs:
         with:
           path: |
             **/node_modules
-          key: runtime-and-compiler-node_modules-v7-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock', 'compiler/yarn.lock') }}
-          # Don't use restore-keys here. Otherwise the cache grows indefinitely.
+          key: runtime-and-compiler-node_modules-v6-${{ 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: node --version
       - run: yarn test ${{ matrix.params }} --ci --shard=${{ matrix.shard }}
 
   # Hardcoded to improve parallelism
@@ -301,7 +306,7 @@ jobs:
         with:
           path: |
             **/node_modules
-          key: runtime-and-compiler-node_modules-v7-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock', 'compiler/yarn.lock') }}
+          key: runtime-and-compiler-node_modules-v6-${{ 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'
@@ -344,8 +349,10 @@ jobs:
         with:
           path: |
             **/node_modules
-          key: runtime-and-compiler-node_modules-v7-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock', 'compiler/yarn.lock') }}
-          # Don't use restore-keys here. Otherwise the cache grows indefinitely.
+          key: runtime-and-compiler-node_modules-v6-${{ 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
@@ -383,6 +390,9 @@ jobs:
           -r=experimental --env=development,
           -r=experimental --env=production,
 
+          # Dev Tools
+          --project=devtools -r=experimental,
+
           # TODO: Update test config to support www build tests
           # - "-r=www-classic --env=development --variant=false"
           # - "-r=www-classic --env=production --variant=false"
@@ -430,8 +440,10 @@ jobs:
         with:
           path: |
             **/node_modules
-          key: runtime-and-compiler-node_modules-v7-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock', 'compiler/yarn.lock') }}
-          # Don't use restore-keys here. Otherwise the cache grows indefinitely.
+          key: runtime-and-compiler-node_modules-v6-${{ 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
@@ -446,54 +458,8 @@ jobs:
           merge-multiple: true
       - name: Display structure of build
         run: ls -R build
-      - run: node --version
       - run: yarn test --build ${{ matrix.test_params }} --shard=${{ matrix.shard }} --ci
 
-  test_build_devtools:
-    name: yarn test-build (devtools)
-    needs: [build_and_lint, runtime_node_modules_cache]
-    strategy:
-      fail-fast: false
-      matrix:
-        shard:
-          - 1/5
-          - 2/5
-          - 3/5
-          - 4/5
-          - 5/5
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v4
-        with:
-          ref: ${{ github.event.inputs.commit_sha != '' && github.event.inputs.commit_sha || github.event.pull_request.head.sha || github.sha }}
-      - uses: actions/setup-node@v4
-        with:
-          node-version-file: '.nvmrc'
-          cache: yarn
-          cache-dependency-path: yarn.lock
-      - name: Restore cached node_modules
-        uses: actions/cache/restore@v4
-        id: node_modules
-        with:
-          path: |
-            **/node_modules
-          key: runtime-node_modules-v7-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
-          # Don't use restore-keys here. Otherwise the cache grows indefinitely.
-      - 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:
-          pattern: _build_*
-          path: build
-          merge-multiple: true
-      - name: Display structure of build
-        run: ls -R build
-      - run: node --version
-      - run: yarn test --build --project=devtools -r=experimental --shard=${{ matrix.shard }} --ci
-
   process_artifacts_combined:
     name: Process artifacts combined
     needs: [build_and_lint, runtime_node_modules_cache]
@@ -517,8 +483,10 @@ jobs:
         with:
           path: |
             **/node_modules
-          key: runtime-node_modules-v7-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
-          # Don't use restore-keys here. Otherwise the cache grows indefinitely.
+          key: runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
+          restore-keys: |
+            runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-
+            runtime-node_modules-v6-
       - name: Ensure clean build directory
         run: rm -rf build
       - run: yarn install --frozen-lockfile
@@ -580,8 +548,10 @@ jobs:
         with:
           path: |
             **/node_modules
-          key: runtime-node_modules-v7-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
-          # Don't use restore-keys here. Otherwise the cache grows indefinitely.
+          key: runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
+          restore-keys: |
+            runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-
+            runtime-node_modules-v6-
       - name: Ensure clean build directory
         run: rm -rf build
       - run: yarn install --frozen-lockfile
@@ -618,8 +588,10 @@ jobs:
         with:
           path: |
             **/node_modules
-          key: runtime-node_modules-v7-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
-          # Don't use restore-keys here. Otherwise the cache grows indefinitely.
+          key: runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
+          restore-keys: |
+            runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-
+            runtime-node_modules-v6-
       - name: Ensure clean build directory
         run: rm -rf build
       - run: yarn install --frozen-lockfile
@@ -768,8 +740,10 @@ jobs:
         with:
           path: |
             **/node_modules
-          key: runtime-node_modules-v7-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
-          # Don't use restore-keys here. Otherwise the cache grows indefinitely.
+          key: runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
+          restore-keys: |
+            runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-
+            runtime-node_modules-v6-
       - name: Ensure clean build directory
         run: rm -rf build
       - run: yarn install --frozen-lockfile
@@ -828,8 +802,10 @@ jobs:
         with:
           path: |
             **/node_modules
-          key: runtime-node_modules-v7-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
-          # Don't use restore-keys here. Otherwise the cache grows indefinitely.
+          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-
       - name: Ensure clean build directory
         run: rm -rf build
       - run: yarn install --frozen-lockfile

.gitignore

@@ -24,8 +24,6 @@ chrome-user-data
 *.swp
 *.swo
 /tmp
-/.worktrees
-.claude/*.local.*
 
 packages/react-devtools-core/dist
 packages/react-devtools-extensions/chrome/build

CHANGELOG.md

@@ -1,9 +1,3 @@
-## 19.2.1 (Dec 3, 2025)
-
-### React Server Components
-
-- Bring React Server Component fixes to Server Actions (@sebmarkbage [#35277](https://github.com/facebook/react/pull/35277))
-
 ## 19.2.0 (October 1st, 2025)
 
 Below is a list of all new features, APIs, and bug fixes.
@@ -77,12 +71,6 @@ Read the [React 19.2 release post](https://react.dev/blog/2025/10/01/react-19-2)
 
 - [createContainer](https://github.com/facebook/react/blob/v19.2.0/packages/react-reconciler/src/ReactFiberReconciler.js#L255-L261) and [createHydrationContainer](https://github.com/facebook/react/blob/v19.2.0/packages/react-reconciler/src/ReactFiberReconciler.js#L305-L312) had their parameter order adjusted after `on*` handlers to account for upcoming experimental APIs
 
-## 19.1.2 (Dec 3, 2025)
-
-### React Server Components
-
-- Bring React Server Component fixes to Server Actions (@sebmarkbage [#35277](https://github.com/facebook/react/pull/35277))
-
 ## 19.1.1 (July 28, 2025)
 
 ### React
@@ -135,12 +123,6 @@ An Owner Stack is a string representing the components that are directly respons
 * 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)
 
-## 19.0.1 (Dec 3, 2025)
-
-### React Server Components
-
-- Bring React Server Component fixes to Server Actions (@sebmarkbage [#35277](https://github.com/facebook/react/pull/35277))
-
 ## 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.

compiler/.claude/settings.json

@@ -1,11 +0,0 @@
-{
-  "permissions": {
-    "allow": [
-      "Bash(yarn snap:*)",
-      "Bash(yarn snap:build)",
-      "Bash(node scripts/enable-feature-flag.js:*)"
-    ],
-    "deny": [],
-    "ask": []
-  }
-}

compiler/.gitignore

@@ -8,9 +8,7 @@ dist
 .vscode
 !packages/playground/.vscode
 testfilter.txt
-.claude/settings.local.json
 
 # forgive
 *.vsix
 .vscode-test
-

compiler/CLAUDE.md

@@ -1,221 +0,0 @@
-# React Compiler Knowledge Base
-
-This document contains knowledge about the React Compiler gathered during development sessions. It serves as a reference for understanding the codebase architecture and key concepts.
-
-## Project Structure
-
-- `packages/babel-plugin-react-compiler/` - Main compiler package
-  - `src/HIR/` - High-level Intermediate Representation types and utilities
-  - `src/Inference/` - Effect inference passes (aliasing, mutation, etc.)
-  - `src/Validation/` - Validation passes that check for errors
-  - `src/Entrypoint/Pipeline.ts` - Main compilation pipeline with pass ordering
-  - `src/__tests__/fixtures/compiler/` - Test fixtures
-    - `error.todo-*.js` - Unsupported feature, correctly throws Todo error (graceful bailout)
-    - `error.bug-*.js` - Known bug, throws wrong error type or incorrect behavior
-    - `*.expect.md` - Expected output for each fixture
-
-## Running Tests
-
-```bash
-# Run all tests
-yarn snap
-
-# Run tests matching a pattern
-# Example: yarn snap -p 'error.*'
-yarn snap -p <pattern>
-
-# Run a single fixture in debug mode. Use the path relative to the __tests__/fixtures/compiler directory
-# For each step of compilation, outputs the step name and state of the compiled program
-# Example: yarn snap -p simple.js -d
-yarn snap -p <file-basename> -d
-
-# Update fixture outputs (also works with -p)
-yarn snap -u
-```
-
-## Version Control
-
-This repository uses Sapling (`sl`) for version control. Sapling is similar to Mercurial: there is not staging area, but new/deleted files must be explicitlyu added/removed.
-
-```bash
-# Check status
-sl status
-
-# Add new files, remove deleted files
-sl addremove
-
-# Commit all changes
-sl commit -m "Your commit message"
-
-# Commit with multi-line message using heredoc
-sl commit -m "$(cat <<'EOF'
-Summary line
-
-Detailed description here
-EOF
-)"
-```
-
-## Key Concepts
-
-### HIR (High-level Intermediate Representation)
-
-The compiler converts source code to HIR for analysis. Key types in `src/HIR/HIR.ts`:
-
-- **HIRFunction** - A function being compiled
-  - `body.blocks` - Map of BasicBlocks
-  - `context` - Captured variables from outer scope
-  - `params` - Function parameters
-  - `returns` - The function's return place
-  - `aliasingEffects` - Effects that describe the function's behavior when called
-
-- **Instruction** - A single operation
-  - `lvalue` - The place being assigned to
-  - `value` - The instruction kind (CallExpression, FunctionExpression, LoadLocal, etc.)
-  - `effects` - Array of AliasingEffects for this instruction
-
-- **Terminal** - Block terminators (return, branch, etc.)
-  - `effects` - Array of AliasingEffects
-
-- **Place** - A reference to a value
-  - `identifier.id` - Unique IdentifierId
-
-- **Phi nodes** - Join points for values from different control flow paths
-  - Located at `block.phis`
-  - `phi.place` - The result place
-  - `phi.operands` - Map of predecessor block to source place
-
-### AliasingEffects System
-
-Effects describe data flow and operations. Defined in `src/Inference/AliasingEffects.ts`:
-
-**Data Flow Effects:**
-- `Impure` - Marks a place as containing an impure value (e.g., Date.now() result, ref.current)
-- `Capture a -> b` - Value from `a` is captured into `b` (mutable capture)
-- `Alias a -> b` - `b` aliases `a`
-- `ImmutableCapture a -> b` - Immutable capture (like Capture but read-only)
-- `Assign a -> b` - Direct assignment
-- `MaybeAlias a -> b` - Possible aliasing
-- `CreateFrom a -> b` - Created from source
-
-**Mutation Effects:**
-- `Mutate value` - Value is mutated
-- `MutateTransitive value` - Value and transitive captures are mutated
-- `MutateConditionally value` - May mutate
-- `MutateTransitiveConditionally value` - May mutate transitively
-
-**Other Effects:**
-- `Render place` - Place is used in render context (JSX props, component return)
-- `Freeze place` - Place is frozen (made immutable)
-- `Create place` - New value created
-- `CreateFunction` - Function expression created, includes `captures` array
-- `Apply` - Function application with receiver, function, args, and result
-
-### Hook Aliasing Signatures
-
-Located in `src/HIR/Globals.ts`, hooks can define custom aliasing signatures to control how data flows through them.
-
-**Structure:**
-```typescript
-aliasing: {
-  receiver: '@receiver',    // The hook function itself
-  params: ['@param0'],      // Named positional parameters
-  rest: '@rest',            // Rest parameters (or null)
-  returns: '@returns',      // Return value
-  temporaries: [],          // Temporary values during execution
-  effects: [                // Array of effects to apply when hook is called
-    {kind: 'Freeze', value: '@param0', reason: ValueReason.HookCaptured},
-    {kind: 'Assign', from: '@param0', into: '@returns'},
-  ],
-}
-```
-
-**Common patterns:**
-
-1. **RenderHookAliasing** (useState, useContext, useMemo, useCallback):
-   - Freezes arguments (`Freeze @rest`)
-   - Marks arguments as render-time (`Render @rest`)
-   - Creates frozen return value
-   - Aliases arguments to return
-
-2. **EffectHookAliasing** (useEffect, useLayoutEffect, useInsertionEffect):
-   - Freezes function and deps
-   - Creates internal effect object
-   - Captures function and deps into effect
-   - Returns undefined
-
-3. **Event handler hooks** (useEffectEvent):
-   - Freezes callback (`Freeze @fn`)
-   - Aliases input to return (`Assign @fn -> @returns`)
-   - NO Render effect (callback not called during render)
-
-**Example: useEffectEvent**
-```typescript
-const UseEffectEventHook = addHook(
-  DEFAULT_SHAPES,
-  {
-    positionalParams: [Effect.Freeze],  // Takes one positional param
-    restParam: null,
-    returnType: {kind: 'Function', ...},
-    calleeEffect: Effect.Read,
-    hookKind: 'useEffectEvent',
-    returnValueKind: ValueKind.Frozen,
-    aliasing: {
-      receiver: '@receiver',
-      params: ['@fn'],              // Name for the callback parameter
-      rest: null,
-      returns: '@returns',
-      temporaries: [],
-      effects: [
-        {kind: 'Freeze', value: '@fn', reason: ValueReason.HookCaptured},
-        {kind: 'Assign', from: '@fn', into: '@returns'},
-        // Note: NO Render effect - callback is not called during render
-      ],
-    },
-  },
-  BuiltInUseEffectEventId,
-);
-
-// Add as both names for compatibility
-['useEffectEvent', UseEffectEventHook],
-['experimental_useEffectEvent', UseEffectEventHook],
-```
-
-**Key insight:** If a hook is missing an `aliasing` config, it falls back to `DefaultNonmutatingHook` which includes a `Render` effect on all arguments. This can cause false positives for hooks like `useEffectEvent` whose callbacks are not called during render.
-
-## Feature Flags
-
-Feature flags are configured in `src/HIR/Environment.ts`, for example `enableJsxOutlining`. Test fixtures can override the active feature flags used for that fixture via a comment pragma on the first line of the fixture input, for example:
-
-```javascript
-// enableJsxOutlining @enableChangeVariableCodegen:false
-
-...code...
-```
-
-Would enable the `enableJsxOutlining` feature and disable the `enableChangeVariableCodegen` feature.
-
-## Debugging Tips
-
-1. Run `yarn snap -p <fixture>` to see full HIR output with effects
-2. Look for `@aliasingEffects=` on FunctionExpressions
-3. Look for `Impure`, `Render`, `Capture` effects on instructions
-4. Check the pass ordering in Pipeline.ts to understand when effects are populated vs validated
-
-## Error Handling for Unsupported Features
-
-When the compiler encounters an unsupported but known pattern, use `CompilerError.throwTodo()` instead of `CompilerError.invariant()`. Todo errors cause graceful bailouts in production; Invariant errors are hard failures indicating unexpected/invalid states.
-
-```typescript
-// Unsupported but expected pattern - graceful bailout
-CompilerError.throwTodo({
-  reason: `Support [description of unsupported feature]`,
-  loc: terminal.loc,
-});
-
-// Invariant is for truly unexpected/invalid states - hard failure
-CompilerError.invariant(false, {
-  reason: `Unexpected [thing]`,
-  loc: terminal.loc,
-});
-```

compiler/apps/playground/.gitignore

@@ -12,7 +12,6 @@
 # next.js
 /.next/
 /out/
-/next-env.d.ts
 
 # production
 /build

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

@@ -14,6 +14,7 @@ import React, {
   unstable_ViewTransition as ViewTransition,
   unstable_addTransitionType as addTransitionType,
   startTransition,
+  Activity,
 } from 'react';
 import {Resizable} from 're-resizable';
 import {useStore, useStoreDispatch} from '../StoreContext';
@@ -33,14 +34,9 @@ export default function ConfigEditor({
 }): React.ReactElement {
   const [isExpanded, setIsExpanded] = useState(false);
 
-  // TODO: Add back <Activity> after upgrading next.js
   return (
     <>
-      <div
-        style={{
-          display: isExpanded ? 'block' : 'none',
-        }}>
-        {/* <Activity mode={isExpanded ? 'visible' : 'hidden'}> */}
+      <Activity mode={isExpanded ? 'visible' : 'hidden'}>
         <ExpandedEditor
           onToggle={() => {
             startTransition(() => {
@@ -50,13 +46,8 @@ export default function ConfigEditor({
           }}
           formattedAppliedConfig={formattedAppliedConfig}
         />
-      </div>
-      <div
-        style={{
-          display: !isExpanded ? 'block' : 'none',
-        }}>
-        {/* </Activity>
-        <Activity mode={isExpanded ? 'hidden' : 'visible'}></Activity> */}
+      </Activity>
+      <Activity mode={isExpanded ? 'hidden' : 'visible'}>
         <CollapsedEditor
           onToggle={() => {
             startTransition(() => {
@@ -65,8 +56,7 @@ export default function ConfigEditor({
             });
           }}
         />
-      </div>
-      {/* </Activity> */}
+      </Activity>
     </>
   );
 }
@@ -126,9 +116,8 @@ function ExpandedEditor({
 
   return (
     <ViewTransition
-      update={{[CONFIG_PANEL_TRANSITION]: 'slide-in', default: 'none'}}>
-      {/* enter={{[CONFIG_PANEL_TRANSITION]: 'slide-in', default: 'none'}}
-      exit={{[CONFIG_PANEL_TRANSITION]: 'slide-out', default: 'none'}}> */}
+      enter={{[CONFIG_PANEL_TRANSITION]: 'slide-in', default: 'none'}}
+      exit={{[CONFIG_PANEL_TRANSITION]: 'slide-out', default: 'none'}}>
       <Resizable
         minWidth={300}
         maxWidth={600}

compiler/apps/playground/next-env.d.ts

@@ -0,0 +1,6 @@
+/// <reference types="next" />
+/// <reference types="next/image-types/global" />
+import "./.next/types/routes.d.ts";
+
+// NOTE: This file should not be edited
+// see https://nextjs.org/docs/app/api-reference/config/typescript for more information.

compiler/apps/playground/package.json

@@ -35,13 +35,13 @@
     "lru-cache": "^11.2.2",
     "lz-string": "^1.5.0",
     "monaco-editor": "^0.52.0",
-    "next": "15.5.9",
+    "next": "15.6.0-canary.7",
     "notistack": "^3.0.0-alpha.7",
     "prettier": "^3.3.3",
     "pretty-format": "^29.3.1",
     "re-resizable": "^6.9.16",
-    "react": "19.2.3",
-    "react-dom": "19.2.3"
+    "react": "19.2",
+    "react-dom": "19.2"
   },
   "devDependencies": {
     "@types/node": "18.11.9",

compiler/apps/playground/tsconfig.json

@@ -19,7 +19,7 @@
     "moduleResolution": "node",
     "resolveJsonModule": true,
     "isolatedModules": true,
-    "jsx": "preserve",
+    "jsx": "react-jsx",
     "incremental": true,
     "plugins": [
       {

compiler/apps/playground/yarn.lock

@@ -715,10 +715,10 @@
   dependencies:
     "@monaco-editor/loader" "^1.6.1"
 
-"@next/env@15.5.9":
-  version "15.5.9"
-  resolved "https://registry.yarnpkg.com/@next/env/-/env-15.5.9.tgz#53c2c34dc17cd87b61f70c6cc211e303123b2ab8"
-  integrity sha512-4GlTZ+EJM7WaW2HEZcyU317tIQDjkQIyENDLxYJfSWlfqguN+dHkZgyQTV/7ykvobU7yEH5gKvreNrH4B6QgIg==
+"@next/env@15.6.0-canary.7":
+  version "15.6.0-canary.7"
+  resolved "https://registry.yarnpkg.com/@next/env/-/env-15.6.0-canary.7.tgz#cdbf2967a9437ef09eef755e203f315acc4d8d8f"
+  integrity sha512-LNZ7Yd3Cl9rKvjYdeJmszf2HmSDP76SQmfafKep2Ux16ZXKoN5OjwVHFTltKNdsB3vt2t+XJzLP2rhw5lBoFBA==
 
 "@next/eslint-plugin-next@15.5.2":
   version "15.5.2"
@@ -727,45 +727,45 @@
   dependencies:
     fast-glob "3.3.1"
 
-"@next/swc-darwin-arm64@15.5.7":
-  version "15.5.7"
-  resolved "https://registry.yarnpkg.com/@next/swc-darwin-arm64/-/swc-darwin-arm64-15.5.7.tgz#f0c9ccfec2cd87cbd4b241ce4c779a7017aed958"
-  integrity sha512-IZwtxCEpI91HVU/rAUOOobWSZv4P2DeTtNaCdHqLcTJU4wdNXgAySvKa/qJCgR5m6KI8UsKDXtO2B31jcaw1Yw==
+"@next/swc-darwin-arm64@15.6.0-canary.7":
+  version "15.6.0-canary.7"
+  resolved "https://registry.yarnpkg.com/@next/swc-darwin-arm64/-/swc-darwin-arm64-15.6.0-canary.7.tgz#628cd34ce9120000f1cb5b08963426431174fc57"
+  integrity sha512-POsBrxhrR3qvqXV+JZ6ZoBc8gJf8rhYe+OedceI1piPVqtJYOJa3EB4eaqcc+kMsllKRrH/goNlhLwtyhE+0Qg==
 
-"@next/swc-darwin-x64@15.5.7":
-  version "15.5.7"
-  resolved "https://registry.yarnpkg.com/@next/swc-darwin-x64/-/swc-darwin-x64-15.5.7.tgz#18009e9fcffc5c0687cc9db24182ddeac56280d9"
-  integrity sha512-UP6CaDBcqaCBuiq/gfCEJw7sPEoX1aIjZHnBWN9v9qYHQdMKvCKcAVs4OX1vIjeE+tC5EIuwDTVIoXpUes29lg==
+"@next/swc-darwin-x64@15.6.0-canary.7":
+  version "15.6.0-canary.7"
+  resolved "https://registry.yarnpkg.com/@next/swc-darwin-x64/-/swc-darwin-x64-15.6.0-canary.7.tgz#37d4ebab14da74a2f8028daf6d76aab410153e06"
+  integrity sha512-lmk9ysBuSiPlAJZTCo/3O4mXNFosg6EDIf4GrmynIwCG2as6/KxzyD1WqFp56Exp8eFDjP7SFapD10sV43vCsA==
 
-"@next/swc-linux-arm64-gnu@15.5.7":
-  version "15.5.7"
-  resolved "https://registry.yarnpkg.com/@next/swc-linux-arm64-gnu/-/swc-linux-arm64-gnu-15.5.7.tgz#fe7c7e08264cf522d4e524299f6d3e63d68d579a"
-  integrity sha512-NCslw3GrNIw7OgmRBxHtdWFQYhexoUCq+0oS2ccjyYLtcn1SzGzeM54jpTFonIMUjNbHmpKpziXnpxhSWLcmBA==
+"@next/swc-linux-arm64-gnu@15.6.0-canary.7":
+  version "15.6.0-canary.7"
+  resolved "https://registry.yarnpkg.com/@next/swc-linux-arm64-gnu/-/swc-linux-arm64-gnu-15.6.0-canary.7.tgz#ce700cc0e0d24763136838223105a524b36694fa"
+  integrity sha512-why8k6d0SBm3AKoOD5S7ir3g+BF34l9oFKIoZrLaZaKBvNGpFcjc7Ovc2TunNMeaMJzv9k1dHYSap0EI5oSuzg==
 
-"@next/swc-linux-arm64-musl@15.5.7":
-  version "15.5.7"
-  resolved "https://registry.yarnpkg.com/@next/swc-linux-arm64-musl/-/swc-linux-arm64-musl-15.5.7.tgz#94228fe293475ec34a5a54284e1056876f43a3cf"
-  integrity sha512-nfymt+SE5cvtTrG9u1wdoxBr9bVB7mtKTcj0ltRn6gkP/2Nu1zM5ei8rwP9qKQP0Y//umK+TtkKgNtfboBxRrw==
+"@next/swc-linux-arm64-musl@15.6.0-canary.7":
+  version "15.6.0-canary.7"
+  resolved "https://registry.yarnpkg.com/@next/swc-linux-arm64-musl/-/swc-linux-arm64-musl-15.6.0-canary.7.tgz#c791b8e15bf2c338b4cc0387fe7afb3ef83ecfcf"
+  integrity sha512-HzvTRsKvYj32Va4YuJN3n3xOxvk+6QwB63d/EsgmdkeA/vrqciUAmJDYpuzZEvRc3Yp2nyPq8KZxtHAr6ISZ2Q==
 
-"@next/swc-linux-x64-gnu@15.5.7":
-  version "15.5.7"
-  resolved "https://registry.yarnpkg.com/@next/swc-linux-x64-gnu/-/swc-linux-x64-gnu-15.5.7.tgz#078c71201dfe7fcfb8fa6dc92aae6c94bc011cdc"
-  integrity sha512-hvXcZvCaaEbCZcVzcY7E1uXN9xWZfFvkNHwbe/n4OkRhFWrs1J1QV+4U1BN06tXLdaS4DazEGXwgqnu/VMcmqw==
+"@next/swc-linux-x64-gnu@15.6.0-canary.7":
+  version "15.6.0-canary.7"
+  resolved "https://registry.yarnpkg.com/@next/swc-linux-x64-gnu/-/swc-linux-x64-gnu-15.6.0-canary.7.tgz#c01c3a3d8e71660c49298dd053d078379b6b5919"
+  integrity sha512-6yRFrg2qWXOqa+1BI53J9EmHWFzKg9U2r+5R7n7BFUp8PH5SC92WBsmYTnh/RkvAYvdupiVzMervwwswCs6kFg==
 
-"@next/swc-linux-x64-musl@15.5.7":
-  version "15.5.7"
-  resolved "https://registry.yarnpkg.com/@next/swc-linux-x64-musl/-/swc-linux-x64-musl-15.5.7.tgz#72947f5357f9226292353e0bb775643da3c7a182"
-  integrity sha512-4IUO539b8FmF0odY6/SqANJdgwn1xs1GkPO5doZugwZ3ETF6JUdckk7RGmsfSf7ws8Qb2YB5It33mvNL/0acqA==
+"@next/swc-linux-x64-musl@15.6.0-canary.7":
+  version "15.6.0-canary.7"
+  resolved "https://registry.yarnpkg.com/@next/swc-linux-x64-musl/-/swc-linux-x64-musl-15.6.0-canary.7.tgz#3f4b39faef4a5f88b13e4c726b008ddc9717f819"
+  integrity sha512-O/JjvOvNK/Wao/OIQaA6evDkxkmFFQgJ1/hI1dVk6/PAeKmW2/Q+6Dodh97eAkOwedS1ZdQl2mojf87TzLvzdQ==
 
-"@next/swc-win32-arm64-msvc@15.5.7":
-  version "15.5.7"
-  resolved "https://registry.yarnpkg.com/@next/swc-win32-arm64-msvc/-/swc-win32-arm64-msvc-15.5.7.tgz#397b912cd51c6a80e32b9c0507ecd82514353941"
-  integrity sha512-CpJVTkYI3ZajQkC5vajM7/ApKJUOlm6uP4BknM3XKvJ7VXAvCqSjSLmM0LKdYzn6nBJVSjdclx8nYJSa3xlTgQ==
+"@next/swc-win32-arm64-msvc@15.6.0-canary.7":
+  version "15.6.0-canary.7"
+  resolved "https://registry.yarnpkg.com/@next/swc-win32-arm64-msvc/-/swc-win32-arm64-msvc-15.6.0-canary.7.tgz#9bc5da0907b7ce67eedda02a6d56a09d9a539ccf"
+  integrity sha512-p9DvrDgnePofZCtiWVY7qZtwXxiOGJlAyy2LoGPYSGOUDhjbTG8j6XMUFXpV9UwpH+l7st522psO1BVzbpT8IQ==
 
-"@next/swc-win32-x64-msvc@15.5.7":
-  version "15.5.7"
-  resolved "https://registry.yarnpkg.com/@next/swc-win32-x64-msvc/-/swc-win32-x64-msvc-15.5.7.tgz#e02b543d9dc6c1631d4ac239cb1177245dfedfe4"
-  integrity sha512-gMzgBX164I6DN+9/PGA+9dQiwmTkE4TloBNx8Kv9UiGARsr9Nba7IpcBRA1iTV9vwlYnrE3Uy6I7Aj6qLjQuqw==
+"@next/swc-win32-x64-msvc@15.6.0-canary.7":
+  version "15.6.0-canary.7"
+  resolved "https://registry.yarnpkg.com/@next/swc-win32-x64-msvc/-/swc-win32-x64-msvc-15.6.0-canary.7.tgz#5b271c591ccbe67d5fa966dd22db86c547414fd1"
+  integrity sha512-f1ywT3xWu4StWKA1mZRyGfelu/h+W0OEEyBxQNXzXyYa0VGZb9LyCNb5cYoNKBm0Bw18Hp1PVe0bHuusemGCcw==
 
 "@nodelib/fs.scandir@2.1.5":
   version "2.1.5"
@@ -3204,25 +3204,25 @@ natural-compare@^1.4.0:
   resolved "https://registry.yarnpkg.com/natural-compare/-/natural-compare-1.4.0.tgz#4abebfeed7541f2c27acfb29bdbbd15c8d5ba4f7"
   integrity sha512-OWND8ei3VtNC9h7V60qff3SVobHr996CTwgxubgyQYEpg290h9J0buyECNNJexkFm5sOajh5G116RYA1c8ZMSw==
 
-next@15.5.9:
-  version "15.5.9"
-  resolved "https://registry.yarnpkg.com/next/-/next-15.5.9.tgz#1b80d05865cc27e710fb4dcfc6fd9e726ed12ad4"
-  integrity sha512-agNLK89seZEtC5zUHwtut0+tNrc0Xw4FT/Dg+B/VLEo9pAcS9rtTKpek3V6kVcVwsB2YlqMaHdfZL4eLEVYuCg==
+next@15.6.0-canary.7:
+  version "15.6.0-canary.7"
+  resolved "https://registry.yarnpkg.com/next/-/next-15.6.0-canary.7.tgz#bfc2ac3c9a78e23d550c303d18247a263e6b5bc1"
+  integrity sha512-4ukX2mxat9wWT6E0Gw/3TOR9ULV1q399E42F86cwsPSFgTWa04ABhcTqO0r9J/QR1YWPR8WEgh9qUzmWA/1yEw==
   dependencies:
-    "@next/env" "15.5.9"
+    "@next/env" "15.6.0-canary.7"
     "@swc/helpers" "0.5.15"
     caniuse-lite "^1.0.30001579"
     postcss "8.4.31"
     styled-jsx "5.1.6"
   optionalDependencies:
-    "@next/swc-darwin-arm64" "15.5.7"
-    "@next/swc-darwin-x64" "15.5.7"
-    "@next/swc-linux-arm64-gnu" "15.5.7"
-    "@next/swc-linux-arm64-musl" "15.5.7"
-    "@next/swc-linux-x64-gnu" "15.5.7"
-    "@next/swc-linux-x64-musl" "15.5.7"
-    "@next/swc-win32-arm64-msvc" "15.5.7"
-    "@next/swc-win32-x64-msvc" "15.5.7"
+    "@next/swc-darwin-arm64" "15.6.0-canary.7"
+    "@next/swc-darwin-x64" "15.6.0-canary.7"
+    "@next/swc-linux-arm64-gnu" "15.6.0-canary.7"
+    "@next/swc-linux-arm64-musl" "15.6.0-canary.7"
+    "@next/swc-linux-x64-gnu" "15.6.0-canary.7"
+    "@next/swc-linux-x64-musl" "15.6.0-canary.7"
+    "@next/swc-win32-arm64-msvc" "15.6.0-canary.7"
+    "@next/swc-win32-x64-msvc" "15.6.0-canary.7"
     sharp "^0.34.3"
 
 node-releases@^2.0.18:
@@ -3582,10 +3582,10 @@ re-resizable@^6.9.16:
   resolved "https://registry.yarnpkg.com/re-resizable/-/re-resizable-6.10.0.tgz#d684a096ab438f1a93f59ad3a580a206b0ce31ee"
   integrity sha512-hysSK0xmA5nz24HBVztlk4yCqCLCvS32E6ZpWxVKop9x3tqCa4yAj1++facrmkOf62JsJHjmjABdKxXofYioCw==
 
-react-dom@19.2.3:
-  version "19.2.3"
-  resolved "https://registry.yarnpkg.com/react-dom/-/react-dom-19.2.3.tgz#f0b61d7e5c4a86773889fcc1853af3ed5f215b17"
-  integrity sha512-yELu4WmLPw5Mr/lmeEpox5rw3RETacE++JgHqQzd2dg+YbJuat3jH4ingc+WPZhxaoFzdv9y33G+F7Nl5O0GBg==
+react-dom@19.2:
+  version "19.2.0"
+  resolved "https://registry.npmjs.org/react-dom/-/react-dom-19.2.0.tgz#00ed1e959c365e9a9d48f8918377465466ec3af8"
+  integrity sha512-UlbRu4cAiGaIewkPyiRGJk0imDN2T3JjieT6spoL2UeSf5od4n5LB/mQ4ejmxhCFT1tYe8IvaFulzynWovsEFQ==
   dependencies:
     scheduler "^0.27.0"
 
@@ -3599,10 +3599,10 @@ react-is@^18.0.0:
   resolved "https://registry.yarnpkg.com/react-is/-/react-is-18.3.1.tgz#e83557dc12eae63a99e003a46388b1dcbb44db7e"
   integrity sha512-/LLMVyas0ljjAtoYiPqYiL8VWXzUUdThrmU5+n20DZv+a+ClRoevUzw5JxU+Ieh5/c87ytoTBV9G1FiKfNJdmg==
 
-react@19.2.3:
-  version "19.2.3"
-  resolved "https://registry.yarnpkg.com/react/-/react-19.2.3.tgz#d83e5e8e7a258cf6b4fe28640515f99b87cd19b8"
-  integrity sha512-Ku/hhYbVjOQnXDZFv2+RibmLFGwFdeeKHFcOTlrt7xplBnya5OGn/hIRDsqDiSUcfORsDC7MPxwork8jBwsIWA==
+react@19.2:
+  version "19.2.0"
+  resolved "https://registry.npmjs.org/react/-/react-19.2.0.tgz#d33dd1721698f4376ae57a54098cb47fc75d93a5"
+  integrity sha512-tmbWg6W31tQLeB5cdIBOicJDJRR2KzXsV7uSK9iNfLWQ5bIZfxuPEHp7M8wiHyHnn0DD1i7w3Zmin0FtkrwoCQ==
 
 read-cache@^1.0.0:
   version "1.0.0"

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

@@ -601,8 +601,7 @@ function printErrorSummary(category: ErrorCategory, message: string): string {
     case ErrorCategory.Syntax:
     case ErrorCategory.UseMemo:
     case ErrorCategory.VoidUseMemo:
-    case ErrorCategory.MemoDependencies:
-    case ErrorCategory.EffectExhaustiveDependencies: {
+    case ErrorCategory.MemoDependencies: {
       heading = 'Error';
       break;
     }
@@ -684,10 +683,6 @@ export enum ErrorCategory {
    * Checks for memoized effect deps
    */
   EffectDependencies = 'EffectDependencies',
-  /**
-   * Checks for exhaustive and extraneous effect dependencies
-   */
-  EffectExhaustiveDependencies = 'EffectExhaustiveDependencies',
   /**
    * Checks for no setState in effect bodies
    */
@@ -843,16 +838,6 @@ function getRuleForCategoryImpl(category: ErrorCategory): LintRule {
         preset: LintRulePreset.Off,
       };
     }
-    case ErrorCategory.EffectExhaustiveDependencies: {
-      return {
-        category,
-        severity: ErrorSeverity.Error,
-        name: 'exhaustive-effect-dependencies',
-        description:
-          'Validates that effect dependencies are exhaustive and without extraneous values',
-        preset: LintRulePreset.Off,
-      };
-    }
     case ErrorCategory.EffectDerivationsOfState: {
       return {
         category,
@@ -869,9 +854,7 @@ function getRuleForCategoryImpl(category: ErrorCategory): LintRule {
         severity: ErrorSeverity.Error,
         name: 'set-state-in-effect',
         description:
-          'Validates against calling setState synchronously in an effect. ' +
-          'This can indicate non-local derived data, a derived event pattern, or ' +
-          'improper external data synchronization.',
+          'Validates against calling setState synchronously in an effect, which can lead to re-renders that degrade performance',
         preset: LintRulePreset.Recommended,
       };
     }

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

@@ -279,20 +279,17 @@ function runWithEnvironment(
       validateNoSetStateInRender(hir).unwrap();
     }
 
-    if (
-      env.config.validateNoDerivedComputationsInEffects_exp &&
-      env.outputMode === 'lint'
-    ) {
+    if (env.config.validateNoDerivedComputationsInEffects_exp) {
       env.logErrors(validateNoDerivedComputationsInEffects_exp(hir));
     } else if (env.config.validateNoDerivedComputationsInEffects) {
       validateNoDerivedComputationsInEffects(hir);
     }
 
-    if (env.config.validateNoSetStateInEffects && env.outputMode === 'lint') {
+    if (env.config.validateNoSetStateInEffects) {
       env.logErrors(validateNoSetStateInEffects(hir, env));
     }
 
-    if (env.config.validateNoJSXInTryStatements && env.outputMode === 'lint') {
+    if (env.config.validateNoJSXInTryStatements) {
       env.logErrors(validateNoJSXInTryStatement(hir));
     }
 
@@ -307,10 +304,7 @@ function runWithEnvironment(
   log({kind: 'hir', name: 'InferReactivePlaces', value: hir});
 
   if (env.enableValidations) {
-    if (
-      env.config.validateExhaustiveMemoizationDependencies ||
-      env.config.validateExhaustiveEffectDependencies
-    ) {
+    if (env.config.validateExhaustiveMemoizationDependencies) {
       // NOTE: this relies on reactivity inference running first
       validateExhaustiveDependencies(hir).unwrap();
     }
@@ -323,11 +317,7 @@ function runWithEnvironment(
     value: hir,
   });
 
-  if (
-    env.enableValidations &&
-    env.config.validateStaticComponents &&
-    env.outputMode === 'lint'
-  ) {
+  if (env.enableValidations && env.config.validateStaticComponents) {
     env.logErrors(validateStaticComponents(hir));
   }
 

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

@@ -4026,7 +4026,6 @@ function lowerAssignment(
           pattern: {
             kind: 'ArrayPattern',
             items,
-            loc: lvalue.node.loc ?? GeneratedSource,
           },
         },
         value,
@@ -4204,7 +4203,6 @@ function lowerAssignment(
           pattern: {
             kind: 'ObjectPattern',
             properties,
-            loc: lvalue.node.loc ?? GeneratedSource,
           },
         },
         value,

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

@@ -221,19 +221,7 @@ export const EnvironmentConfigSchema = z.object({
   /**
    * Validate that dependencies supplied to manual memoization calls are exhaustive.
    */
-  validateExhaustiveMemoizationDependencies: z.boolean().default(true),
-
-  /**
-   * Validate that dependencies supplied to effect hooks are exhaustive.
-   * Can be:
-   * - 'off': No validation (default)
-   * - 'all': Validate and report both missing and extra dependencies
-   * - 'missing-only': Only report missing dependencies
-   * - 'extra-only': Only report extra/unnecessary dependencies
-   */
-  validateExhaustiveEffectDependencies: z
-    .enum(['off', 'all', 'missing-only', 'extra-only'])
-    .default('off'),
+  validateExhaustiveMemoizationDependencies: z.boolean().default(false),
 
   /**
    * When this is true, rather than pruning existing manual memoization but ensuring or validating
@@ -330,12 +318,6 @@ export const EnvironmentConfigSchema = z.object({
    */
   validateNoSetStateInRender: z.boolean().default(true),
 
-  /**
-   * When enabled, changes the behavior of validateNoSetStateInRender to recommend
-   * using useKeyedState instead of the manual pattern for resetting state.
-   */
-  enableUseKeyedState: z.boolean().default(false),
-
   /**
    * Validates that setState is not called synchronously within an effect (useEffect and friends).
    * Scheduling a setState (with an event listener, subscription, etc) is valid.
@@ -707,16 +689,6 @@ export const EnvironmentConfigSchema = z.object({
    */
   enableAllowSetStateFromRefsInEffects: z.boolean().default(true),
 
-  /**
-   * When enabled, provides verbose error messages for setState calls within effects,
-   * presenting multiple possible fixes to the user/agent since we cannot statically
-   * determine which specific use-case applies:
-   * 1. Non-local derived data - requires restructuring state ownership
-   * 2. Derived event pattern - detecting when a prop changes
-   * 3. Force update / external sync - should use useSyncExternalStore
-   */
-  enableVerboseNoSetStateInEffect: z.boolean().default(false),
-
   /**
    * Enables inference of event handler types for JSX props on built-in DOM elements.
    * When enabled, functions passed to event handler props (props starting with "on")

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

@@ -694,13 +694,11 @@ export type SpreadPattern = {
 export type ArrayPattern = {
   kind: 'ArrayPattern';
   items: Array<Place | SpreadPattern | Hole>;
-  loc: SourceLocation;
 };
 
 export type ObjectPattern = {
   kind: 'ObjectPattern';
   properties: Array<ObjectProperty | SpreadPattern>;
-  loc: SourceLocation;
 };
 
 export type ObjectPropertyKey =
@@ -805,11 +803,9 @@ export type ManualMemoDependency = {
     | {
         kind: 'NamedLocal';
         value: Place;
-        constant: boolean;
       }
     | {kind: 'Global'; identifierName: string};
   path: DependencyPath;
-  loc: SourceLocation;
 };
 
 export type StartMemoize = {
@@ -2025,11 +2021,6 @@ export function isUseInsertionEffectHookType(id: Identifier): boolean {
     id.type.shapeId === 'BuiltInUseInsertionEffectHook'
   );
 }
-export function isUseEffectEventType(id: Identifier): boolean {
-  return (
-    id.type.kind === 'Function' && id.type.shapeId === 'BuiltInUseEffectEvent'
-  );
-}
 
 export function isUseContextHookType(id: Identifier): boolean {
   return (

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

@@ -65,7 +65,6 @@ export function collectMaybeMemoDependencies(
           identifierName: value.binding.name,
         },
         path: [],
-        loc: value.loc,
       };
     }
     case 'PropertyLoad': {
@@ -75,7 +74,6 @@ export function collectMaybeMemoDependencies(
           root: object.root,
           // TODO: determine if the access is optional
           path: [...object.path, {property: value.property, optional}],
-          loc: value.loc,
         };
       }
       break;
@@ -94,10 +92,8 @@ export function collectMaybeMemoDependencies(
           root: {
             kind: 'NamedLocal',
             value: {...value.place},
-            constant: false,
           },
           path: [],
-          loc: value.place.loc,
         };
       }
       break;

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

@@ -609,19 +609,6 @@ function evaluateInstruction(
       constantPropagationImpl(value.loweredFunc.func, constants);
       return null;
     }
-    case 'StartMemoize': {
-      if (value.deps != null) {
-        for (const dep of value.deps) {
-          if (dep.root.kind === 'NamedLocal') {
-            const placeValue = read(constants, dep.root.value);
-            if (placeValue != null && placeValue.kind === 'Primitive') {
-              dep.root.constant = true;
-            }
-          }
-        }
-      }
-      return null;
-    }
     default: {
       // TODO: handle more cases
       return null;

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

@@ -515,7 +515,6 @@ function emitDestructureProps(
         pattern: {
           kind: 'ObjectPattern',
           properties,
-          loc: GeneratedSource,
         },
         kind: InstructionKind.Let,
       },

compiler/packages/babel-plugin-react-compiler/src/ReactiveScopes/CodegenReactiveFunction.ts

@@ -702,7 +702,7 @@ function codegenReactiveScope(
     outputComments.push(name.name);
     if (!cx.hasDeclared(identifier)) {
       statements.push(
-        t.variableDeclaration('let', [createVariableDeclarator(name, null)]),
+        t.variableDeclaration('let', [t.variableDeclarator(name)]),
       );
     }
     cacheLoads.push({name, index, value: wrapCacheDep(cx, name)});
@@ -1387,7 +1387,7 @@ function codegenInstructionNullable(
           suggestions: null,
         });
         return createVariableDeclaration(instr.loc, 'const', [
-          createVariableDeclarator(codegenLValue(cx, lvalue), value),
+          t.variableDeclarator(codegenLValue(cx, lvalue), value),
         ]);
       }
       case InstructionKind.Function: {
@@ -1451,7 +1451,7 @@ function codegenInstructionNullable(
           suggestions: null,
         });
         return createVariableDeclaration(instr.loc, 'let', [
-          createVariableDeclarator(codegenLValue(cx, lvalue), value),
+          t.variableDeclarator(codegenLValue(cx, lvalue), value),
         ]);
       }
       case InstructionKind.Reassign: {
@@ -1691,9 +1691,6 @@ function withLoc<T extends (...args: Array<any>) => t.Node>(
   };
 }
 
-const createIdentifier = withLoc(t.identifier);
-const createArrayPattern = withLoc(t.arrayPattern);
-const createObjectPattern = withLoc(t.objectPattern);
 const createBinaryExpression = withLoc(t.binaryExpression);
 const createExpressionStatement = withLoc(t.expressionStatement);
 const _createLabelledStatement = withLoc(t.labeledStatement);
@@ -1725,31 +1722,6 @@ const createTryStatement = withLoc(t.tryStatement);
 const createBreakStatement = withLoc(t.breakStatement);
 const createContinueStatement = withLoc(t.continueStatement);
 
-function createVariableDeclarator(
-  id: t.LVal,
-  init?: t.Expression | null,
-): t.VariableDeclarator {
-  const node = t.variableDeclarator(id, init);
-
-  /*
-   * The variable declarator location is not preserved in HIR, however, we can use the
-   * start location of the id and the end location of the init to recreate the
-   * exact original variable declarator location.
-   *
-   * Or if init is null, we likely have a declaration without an initializer, so we can use the id.loc.end as the end location.
-   */
-  if (id.loc && (init === null || init?.loc)) {
-    node.loc = {
-      start: id.loc.start,
-      end: init?.loc?.end ?? id.loc.end,
-      filename: id.loc.filename,
-      identifierName: undefined,
-    };
-  }
-
-  return node;
-}
-
 function createHookGuard(
   guard: ExternalFunction,
   context: ProgramContext,
@@ -1857,7 +1829,7 @@ function codegenInstruction(
       );
     } else {
       return createVariableDeclaration(instr.loc, 'const', [
-        createVariableDeclarator(
+        t.variableDeclarator(
           convertIdentifier(instr.lvalue.identifier),
           expressionValue,
         ),
@@ -2784,7 +2756,7 @@ function codegenArrayPattern(
 ): t.ArrayPattern {
   const hasHoles = !pattern.items.every(e => e.kind !== 'Hole');
   if (hasHoles) {
-    const result = createArrayPattern(pattern.loc, []);
+    const result = t.arrayPattern([]);
     /*
      * Older versions of babel have a validation bug fixed by
      * https://github.com/babel/babel/pull/10917
@@ -2805,8 +2777,7 @@ function codegenArrayPattern(
     }
     return result;
   } else {
-    return createArrayPattern(
-      pattern.loc,
+    return t.arrayPattern(
       pattern.items.map(item => {
         if (item.kind === 'Hole') {
           return null;
@@ -2826,8 +2797,7 @@ function codegenLValue(
       return codegenArrayPattern(cx, pattern);
     }
     case 'ObjectPattern': {
-      return createObjectPattern(
-        pattern.loc,
+      return t.objectPattern(
         pattern.properties.map(property => {
           if (property.kind === 'ObjectProperty') {
             const key = codegenObjectPropertyKey(cx, property.key);
@@ -2946,7 +2916,7 @@ function convertIdentifier(identifier: Identifier): t.Identifier {
       suggestions: null,
     },
   );
-  return createIdentifier(identifier.loc, identifier.name.value);
+  return t.identifier(identifier.name.value);
 }
 
 function compareScopeDependency(

compiler/packages/babel-plugin-react-compiler/src/ReactiveScopes/InferReactiveScopeVariables.ts

@@ -389,6 +389,14 @@ export function findDisjointMutableValues(
              */
             operand.identifier.mutableRange.start > 0
           ) {
+            if (
+              instr.value.kind === 'FunctionExpression' ||
+              instr.value.kind === 'ObjectMethod'
+            ) {
+              if (operand.identifier.type.kind === 'Primitive') {
+                continue;
+              }
+            }
             operands.push(operand.identifier);
           }
         }

compiler/packages/babel-plugin-react-compiler/src/Validation/ValidateExhaustiveDependencies.ts

@@ -10,7 +10,6 @@ import {
   CompilerDiagnostic,
   CompilerError,
   CompilerSuggestionOperation,
-  Effect,
   SourceLocation,
 } from '..';
 import {CompilerSuggestion, ErrorCategory} from '../CompilerError';
@@ -19,13 +18,10 @@ import {
   BlockId,
   DependencyPath,
   FinishMemoize,
-  GeneratedSource,
   HIRFunction,
   Identifier,
   IdentifierId,
   InstructionKind,
-  isEffectEventFunctionType,
-  isPrimitiveType,
   isStableType,
   isSubPath,
   isSubPathIgnoringOptionals,
@@ -43,7 +39,6 @@ import {
 } from '../HIR/visitors';
 import {Result} from '../Utils/Result';
 import {retainWhere} from '../Utils/utils';
-import {isEffectHook} from './ValidateMemoizedEffectDependencies';
 
 const DEBUG = false;
 
@@ -58,18 +53,20 @@ const DEBUG = false;
  * - If the manual dependencies had extraneous deps, then auto memoization
  *   will remove them and cause the value to update *less* frequently.
  *
- * The implementation compares the manual dependencies against the values
- * actually used within the memoization function
- * - For each value V referenced in the memo function, either:
- *   - If the value is non-reactive *and* a known stable type, then the
- *     value may optionally be specified as an exact dependency.
- *   - Otherwise, report an error unless there is a manual dependency that will
- *     invalidate whenever V invalidates. If `x.y.z` is referenced, there must
- *     be a manual dependency for `x.y.z`, `x.y`, or `x`. Note that we assume
- *     no interior mutability, ie we assume that any changes to inner paths must
- *     always cause the other path to change as well.
- * - Any dependencies that do not correspond to a value referenced in the memo
- *   function are considered extraneous and throw an error
+ * We consider a value V as missing if ALL of the following conditions are met:
+ * - V is reactive
+ * - There is no manual dependency path P such that whenever V would change,
+ *   P would also change. If V is `x.y.z`, this means there must be some
+ *   path P that is either `x.y.z`, `x.y`, or `x`. Note that we assume no
+ *   interior mutability, such that a shorter path "covers" changes to longer
+ *   more precise paths.
+ *
+ * We consider a value V extraneous if either of the folowing are true:
+ * - V is a reactive local that is unreferenced
+ * - V is a global that is unreferenced
+ *
+ * In other words, we allow extraneous non-reactive values since we know they cannot
+ * impact how often the memoization would run.
  *
  * ## TODO: Invalid, Complex Deps
  *
@@ -89,7 +86,6 @@ const DEBUG = false;
 export function validateExhaustiveDependencies(
   fn: HIRFunction,
 ): Result<void, CompilerError> {
-  const env = fn.env;
   const reactive = collectReactiveIdentifiersHIR(fn);
 
   const temporaries: Map<IdentifierId, Temporary> = new Map();
@@ -131,19 +127,195 @@ export function validateExhaustiveDependencies(
         loc: value.loc,
       },
     );
-    if (env.config.validateExhaustiveMemoizationDependencies) {
-      visitCandidateDependency(value.decl, temporaries, dependencies, locals);
-      const inferred: Array<InferredDependency> = Array.from(dependencies);
-
-      const diagnostic = validateDependencies(
-        inferred,
-        startMemo.deps ?? [],
-        reactive,
-        startMemo.depsLoc,
-        ErrorCategory.MemoDependencies,
-        'all',
+    visitCandidateDependency(value.decl, temporaries, dependencies, locals);
+    const inferred: Array<InferredDependency> = Array.from(dependencies);
+    // Sort dependencies by name and path, with shorter/non-optional paths first
+    inferred.sort((a, b) => {
+      if (a.kind === 'Global' && b.kind == 'Global') {
+        return a.binding.name.localeCompare(b.binding.name);
+      } else if (a.kind == 'Local' && b.kind == 'Local') {
+        CompilerError.simpleInvariant(
+          a.identifier.name != null &&
+            a.identifier.name.kind === 'named' &&
+            b.identifier.name != null &&
+            b.identifier.name.kind === 'named',
+          {
+            reason: 'Expected dependencies to be named variables',
+            loc: a.loc,
+          },
+        );
+        if (a.identifier.id !== b.identifier.id) {
+          return a.identifier.name.value.localeCompare(b.identifier.name.value);
+        }
+        if (a.path.length !== b.path.length) {
+          // if a's path is shorter this returns a negative, sorting a first
+          return a.path.length - b.path.length;
+        }
+        for (let i = 0; i < a.path.length; i++) {
+          const aProperty = a.path[i];
+          const bProperty = b.path[i];
+          const aOptional = aProperty.optional ? 0 : 1;
+          const bOptional = bProperty.optional ? 0 : 1;
+          if (aOptional !== bOptional) {
+            // sort non-optionals first
+            return aOptional - bOptional;
+          } else if (aProperty.property !== bProperty.property) {
+            return String(aProperty.property).localeCompare(
+              String(bProperty.property),
+            );
+          }
+        }
+        return 0;
+      } else {
+        const aName =
+          a.kind === 'Global' ? a.binding.name : a.identifier.name?.value;
+        const bName =
+          b.kind === 'Global' ? b.binding.name : b.identifier.name?.value;
+        if (aName != null && bName != null) {
+          return aName.localeCompare(bName);
+        }
+        return 0;
+      }
+    });
+    // remove redundant inferred dependencies
+    retainWhere(inferred, (dep, ix) => {
+      const match = inferred.findIndex(prevDep => {
+        return (
+          isEqualTemporary(prevDep, dep) ||
+          (prevDep.kind === 'Local' &&
+            dep.kind === 'Local' &&
+            prevDep.identifier.id === dep.identifier.id &&
+            isSubPath(prevDep.path, dep.path))
+        );
+      });
+      // only retain entries that don't have a prior match
+      return match === -1 || match >= ix;
+    });
+    // Validate that all manual dependencies belong there
+    if (DEBUG) {
+      console.log('manual');
+      console.log(
+        (startMemo.deps ?? [])
+          .map(x => '  ' + printManualMemoDependency(x))
+          .join('\n'),
       );
-      if (diagnostic != null) {
+      console.log('inferred');
+      console.log(
+        inferred.map(x => '  ' + printInferredDependency(x)).join('\n'),
+      );
+    }
+    const manualDependencies = startMemo.deps ?? [];
+    const matched: Set<ManualMemoDependency> = new Set();
+    const missing: Array<Extract<InferredDependency, {kind: 'Local'}>> = [];
+    const extra: Array<ManualMemoDependency> = [];
+    for (const inferredDependency of inferred) {
+      if (inferredDependency.kind === 'Global') {
+        for (const manualDependency of manualDependencies) {
+          if (
+            manualDependency.root.kind === 'Global' &&
+            manualDependency.root.identifierName ===
+              inferredDependency.binding.name
+          ) {
+            matched.add(manualDependency);
+            extra.push(manualDependency);
+          }
+        }
+        continue;
+      }
+      CompilerError.simpleInvariant(inferredDependency.kind === 'Local', {
+        reason: 'Unexpected function dependency',
+        loc: value.loc,
+      });
+      const isRequiredDependency = reactive.has(
+        inferredDependency.identifier.id,
+      );
+      let hasMatchingManualDependency = false;
+      for (const manualDependency of manualDependencies) {
+        if (
+          manualDependency.root.kind === 'NamedLocal' &&
+          manualDependency.root.value.identifier.id ===
+            inferredDependency.identifier.id &&
+          (areEqualPaths(manualDependency.path, inferredDependency.path) ||
+            isSubPathIgnoringOptionals(
+              manualDependency.path,
+              inferredDependency.path,
+            ))
+        ) {
+          hasMatchingManualDependency = true;
+          matched.add(manualDependency);
+          if (!isRequiredDependency) {
+            extra.push(manualDependency);
+          }
+        }
+      }
+      if (isRequiredDependency && !hasMatchingManualDependency) {
+        missing.push(inferredDependency);
+      }
+    }
+
+    for (const dep of startMemo.deps ?? []) {
+      if (matched.has(dep)) {
+        continue;
+      }
+      extra.push(dep);
+    }
+
+    /**
+     * Per docblock, we only consider dependencies as extraneous if
+     * they are unused globals or reactive locals. Notably, this allows
+     * non-reactive locals.
+     */
+    retainWhere(extra, dep => {
+      return dep.root.kind === 'Global' || dep.root.value.reactive;
+    });
+
+    if (missing.length !== 0 || extra.length !== 0) {
+      let suggestions: Array<CompilerSuggestion> | null = null;
+      if (startMemo.depsLoc != null && typeof startMemo.depsLoc !== 'symbol') {
+        suggestions = [
+          {
+            description: 'Update dependencies',
+            range: [startMemo.depsLoc.start.index, startMemo.depsLoc.end.index],
+            op: CompilerSuggestionOperation.Replace,
+            text: `[${inferred.map(printInferredDependency).join(', ')}]`,
+          },
+        ];
+      }
+      if (missing.length !== 0) {
+        const diagnostic = CompilerDiagnostic.create({
+          category: ErrorCategory.MemoDependencies,
+          reason: 'Found missing memoization dependencies',
+          description:
+            'Missing dependencies can cause a value not to update when those inputs change, ' +
+            'resulting in stale UI',
+          suggestions,
+        });
+        for (const dep of missing) {
+          let reactiveStableValueHint = '';
+          if (isStableType(dep.identifier)) {
+            reactiveStableValueHint =
+              '. Refs, setState functions, and other "stable" values generally do not need to be added as dependencies, but this variable may change over time to point to different values';
+          }
+          diagnostic.withDetails({
+            kind: 'error',
+            message: `Missing dependency \`${printInferredDependency(dep)}\`${reactiveStableValueHint}`,
+            loc: dep.loc,
+          });
+        }
+        error.pushDiagnostic(diagnostic);
+      } else if (extra.length !== 0) {
+        const diagnostic = CompilerDiagnostic.create({
+          category: ErrorCategory.MemoDependencies,
+          reason: 'Found unnecessary memoization dependencies',
+          description:
+            'Unnecessary dependencies can cause a value to update more often than necessary, ' +
+            'causing performance regressions and effects to fire more often than expected',
+        });
+        diagnostic.withDetails({
+          kind: 'error',
+          message: `Unnecessary dependencies ${extra.map(dep => `\`${printManualMemoDependency(dep)}\``).join(', ')}`,
+          loc: startMemo.depsLoc ?? value.loc,
+        });
         error.pushDiagnostic(diagnostic);
       }
     }
@@ -159,347 +331,18 @@ export function validateExhaustiveDependencies(
     {
       onStartMemoize,
       onFinishMemoize,
-      onEffect: (inferred, manual, manualMemoLoc) => {
-        if (env.config.validateExhaustiveEffectDependencies === 'off') {
-          return;
-        }
-        if (DEBUG) {
-          console.log(Array.from(inferred, printInferredDependency));
-          console.log(Array.from(manual, printInferredDependency));
-        }
-        const manualDeps: Array<ManualMemoDependency> = [];
-        for (const dep of manual) {
-          if (dep.kind === 'Local') {
-            manualDeps.push({
-              root: {
-                kind: 'NamedLocal',
-                constant: false,
-                value: {
-                  effect: Effect.Read,
-                  identifier: dep.identifier,
-                  kind: 'Identifier',
-                  loc: dep.loc,
-                  reactive: reactive.has(dep.identifier.id),
-                },
-              },
-              path: dep.path,
-              loc: dep.loc,
-            });
-          } else {
-            manualDeps.push({
-              root: {
-                kind: 'Global',
-                identifierName: dep.binding.name,
-              },
-              path: [],
-              loc: GeneratedSource,
-            });
-          }
-        }
-        const effectReportMode =
-          typeof env.config.validateExhaustiveEffectDependencies === 'string'
-            ? env.config.validateExhaustiveEffectDependencies
-            : 'all';
-        const diagnostic = validateDependencies(
-          Array.from(inferred),
-          manualDeps,
-          reactive,
-          manualMemoLoc,
-          ErrorCategory.EffectExhaustiveDependencies,
-          effectReportMode,
-        );
-        if (diagnostic != null) {
-          error.pushDiagnostic(diagnostic);
-        }
-      },
     },
     false, // isFunctionExpression
   );
   return error.asResult();
 }
 
-function validateDependencies(
-  inferred: Array<InferredDependency>,
-  manualDependencies: Array<ManualMemoDependency>,
-  reactive: Set<IdentifierId>,
-  manualMemoLoc: SourceLocation | null,
-  category:
-    | ErrorCategory.MemoDependencies
-    | ErrorCategory.EffectExhaustiveDependencies,
-  exhaustiveDepsReportMode: 'all' | 'missing-only' | 'extra-only',
-): CompilerDiagnostic | null {
-  // Sort dependencies by name and path, with shorter/non-optional paths first
-  inferred.sort((a, b) => {
-    if (a.kind === 'Global' && b.kind == 'Global') {
-      return a.binding.name.localeCompare(b.binding.name);
-    } else if (a.kind == 'Local' && b.kind == 'Local') {
-      CompilerError.simpleInvariant(
-        a.identifier.name != null &&
-          a.identifier.name.kind === 'named' &&
-          b.identifier.name != null &&
-          b.identifier.name.kind === 'named',
-        {
-          reason: 'Expected dependencies to be named variables',
-          loc: a.loc,
-        },
-      );
-      if (a.identifier.id !== b.identifier.id) {
-        return a.identifier.name.value.localeCompare(b.identifier.name.value);
-      }
-      if (a.path.length !== b.path.length) {
-        // if a's path is shorter this returns a negative, sorting a first
-        return a.path.length - b.path.length;
-      }
-      for (let i = 0; i < a.path.length; i++) {
-        const aProperty = a.path[i];
-        const bProperty = b.path[i];
-        const aOptional = aProperty.optional ? 0 : 1;
-        const bOptional = bProperty.optional ? 0 : 1;
-        if (aOptional !== bOptional) {
-          // sort non-optionals first
-          return aOptional - bOptional;
-        } else if (aProperty.property !== bProperty.property) {
-          return String(aProperty.property).localeCompare(
-            String(bProperty.property),
-          );
-        }
-      }
-      return 0;
-    } else {
-      const aName =
-        a.kind === 'Global' ? a.binding.name : a.identifier.name?.value;
-      const bName =
-        b.kind === 'Global' ? b.binding.name : b.identifier.name?.value;
-      if (aName != null && bName != null) {
-        return aName.localeCompare(bName);
-      }
-      return 0;
-    }
-  });
-  // remove redundant inferred dependencies
-  retainWhere(inferred, (dep, ix) => {
-    const match = inferred.findIndex(prevDep => {
-      return (
-        isEqualTemporary(prevDep, dep) ||
-        (prevDep.kind === 'Local' &&
-          dep.kind === 'Local' &&
-          prevDep.identifier.id === dep.identifier.id &&
-          isSubPath(prevDep.path, dep.path))
-      );
-    });
-    // only retain entries that don't have a prior match
-    return match === -1 || match >= ix;
-  });
-  // Validate that all manual dependencies belong there
-  if (DEBUG) {
-    console.log('manual');
-    console.log(
-      manualDependencies
-        .map(x => '  ' + printManualMemoDependency(x))
-        .join('\n'),
-    );
-    console.log('inferred');
-    console.log(
-      inferred.map(x => '  ' + printInferredDependency(x)).join('\n'),
-    );
-  }
-  const matched: Set<ManualMemoDependency> = new Set();
-  const missing: Array<Extract<InferredDependency, {kind: 'Local'}>> = [];
-  const extra: Array<ManualMemoDependency> = [];
-  for (const inferredDependency of inferred) {
-    if (inferredDependency.kind === 'Global') {
-      for (const manualDependency of manualDependencies) {
-        if (
-          manualDependency.root.kind === 'Global' &&
-          manualDependency.root.identifierName ===
-            inferredDependency.binding.name
-        ) {
-          matched.add(manualDependency);
-          extra.push(manualDependency);
-        }
-      }
-      continue;
-    }
-    CompilerError.simpleInvariant(inferredDependency.kind === 'Local', {
-      reason: 'Unexpected function dependency',
-      loc: inferredDependency.loc,
-    });
-    /**
-     * Skip effect event functions as they are not valid dependencies
-     */
-    if (isEffectEventFunctionType(inferredDependency.identifier)) {
-      continue;
-    }
-    let hasMatchingManualDependency = false;
-    for (const manualDependency of manualDependencies) {
-      if (
-        manualDependency.root.kind === 'NamedLocal' &&
-        manualDependency.root.value.identifier.id ===
-          inferredDependency.identifier.id &&
-        (areEqualPaths(manualDependency.path, inferredDependency.path) ||
-          isSubPathIgnoringOptionals(
-            manualDependency.path,
-            inferredDependency.path,
-          ))
-      ) {
-        hasMatchingManualDependency = true;
-        matched.add(manualDependency);
-      }
-    }
-    if (
-      hasMatchingManualDependency ||
-      isOptionalDependency(inferredDependency, reactive)
-    ) {
-      continue;
-    }
-
-    missing.push(inferredDependency);
-  }
-
-  for (const dep of manualDependencies) {
-    if (matched.has(dep)) {
-      continue;
-    }
-    if (dep.root.kind === 'NamedLocal' && dep.root.constant) {
-      CompilerError.simpleInvariant(
-        !dep.root.value.reactive && isPrimitiveType(dep.root.value.identifier),
-        {
-          reason: 'Expected constant-folded dependency to be non-reactive',
-          loc: dep.root.value.loc,
-        },
-      );
-      /*
-       * Constant primitives can get constant-folded, which means we won't
-       * see a LoadLocal for the value within the memo function.
-       */
-      continue;
-    }
-    extra.push(dep);
-  }
-
-  // Filter based on report mode
-  const filteredMissing =
-    exhaustiveDepsReportMode === 'extra-only' ? [] : missing;
-  const filteredExtra =
-    exhaustiveDepsReportMode === 'missing-only' ? [] : extra;
-
-  if (filteredMissing.length !== 0 || filteredExtra.length !== 0) {
-    let suggestion: CompilerSuggestion | null = null;
-    if (
-      manualMemoLoc != null &&
-      typeof manualMemoLoc !== 'symbol' &&
-      manualMemoLoc.start.index != null &&
-      manualMemoLoc.end.index != null
-    ) {
-      suggestion = {
-        description: 'Update dependencies',
-        range: [manualMemoLoc.start.index, manualMemoLoc.end.index],
-        op: CompilerSuggestionOperation.Replace,
-        text: `[${inferred
-          .filter(
-            dep =>
-              dep.kind === 'Local' &&
-              !isOptionalDependency(dep, reactive) &&
-              !isEffectEventFunctionType(dep.identifier),
-          )
-          .map(printInferredDependency)
-          .join(', ')}]`,
-      };
-    }
-    const diagnostic = createDiagnostic(
-      category,
-      filteredMissing,
-      filteredExtra,
-      suggestion,
-    );
-    for (const dep of filteredMissing) {
-      let reactiveStableValueHint = '';
-      if (isStableType(dep.identifier)) {
-        reactiveStableValueHint =
-          '. Refs, setState functions, and other "stable" values generally do not need to be added ' +
-          'as dependencies, but this variable may change over time to point to different values';
-      }
-      diagnostic.withDetails({
-        kind: 'error',
-        message: `Missing dependency \`${printInferredDependency(dep)}\`${reactiveStableValueHint}`,
-        loc: dep.loc,
-      });
-    }
-    for (const dep of filteredExtra) {
-      if (dep.root.kind === 'Global') {
-        diagnostic.withDetails({
-          kind: 'error',
-          message:
-            `Unnecessary dependency \`${printManualMemoDependency(dep)}\`. ` +
-            'Values declared outside of a component/hook should not be listed as ' +
-            'dependencies as the component will not re-render if they change',
-          loc: dep.loc ?? manualMemoLoc,
-        });
-      } else {
-        const root = dep.root.value;
-        const matchingInferred = inferred.find(
-          (
-            inferredDep,
-          ): inferredDep is Extract<InferredDependency, {kind: 'Local'}> => {
-            return (
-              inferredDep.kind === 'Local' &&
-              inferredDep.identifier.id === root.identifier.id &&
-              isSubPathIgnoringOptionals(inferredDep.path, dep.path)
-            );
-          },
-        );
-        if (
-          matchingInferred != null &&
-          isEffectEventFunctionType(matchingInferred.identifier)
-        ) {
-          diagnostic.withDetails({
-            kind: 'error',
-            message:
-              `Functions returned from \`useEffectEvent\` must not be included in the dependency array. ` +
-              `Remove \`${printManualMemoDependency(dep)}\` from the dependencies.`,
-            loc: dep.loc ?? manualMemoLoc,
-          });
-        } else if (
-          matchingInferred != null &&
-          !isOptionalDependency(matchingInferred, reactive)
-        ) {
-          diagnostic.withDetails({
-            kind: 'error',
-            message:
-              `Overly precise dependency \`${printManualMemoDependency(dep)}\`, ` +
-              `use \`${printInferredDependency(matchingInferred)}\` instead`,
-            loc: dep.loc ?? manualMemoLoc,
-          });
-        } else {
-          /**
-           * Else this dependency doesn't correspond to anything referenced in the memo function,
-           * or is an optional dependency so we don't want to suggest adding it
-           */
-          diagnostic.withDetails({
-            kind: 'error',
-            message: `Unnecessary dependency \`${printManualMemoDependency(dep)}\``,
-            loc: dep.loc ?? manualMemoLoc,
-          });
-        }
-      }
-    }
-    if (suggestion != null) {
-      diagnostic.withDetails({
-        kind: 'hint',
-        message: `Inferred dependencies: \`${suggestion.text}\``,
-      });
-    }
-    return diagnostic;
-  }
-  return null;
-}
-
 function addDependency(
   dep: Temporary,
   dependencies: Set<InferredDependency>,
   locals: Set<IdentifierId>,
 ): void {
-  if (dep.kind === 'Aggregate') {
+  if (dep.kind === 'Function') {
     for (const x of dep.dependencies) {
       addDependency(x, dependencies, locals);
     }
@@ -582,14 +425,9 @@ function collectDependencies(
       dependencies: Set<InferredDependency>,
       locals: Set<IdentifierId>,
     ) => void;
-    onEffect: (
-      inferred: Set<InferredDependency>,
-      manual: Set<InferredDependency>,
-      manualMemoLoc: SourceLocation | null,
-    ) => void;
   } | null,
   isFunctionExpression: boolean,
-): Extract<Temporary, {kind: 'Aggregate'}> {
+): Extract<Temporary, {kind: 'Function'}> {
   const optionals = findOptionalPlaces(fn);
   if (DEBUG) {
     console.log(prettyFormat(optionals));
@@ -608,25 +446,25 @@ function collectDependencies(
   }
   for (const block of fn.body.blocks.values()) {
     for (const phi of block.phis) {
-      const deps: Array<InferredDependency> = [];
+      let deps: Array<Temporary> | null = null;
       for (const operand of phi.operands.values()) {
         const dep = temporaries.get(operand.identifier.id);
         if (dep == null) {
           continue;
         }
-        if (dep.kind === 'Aggregate') {
-          deps.push(...dep.dependencies);
+        if (deps == null) {
+          deps = [dep];
         } else {
           deps.push(dep);
         }
       }
-      if (deps.length === 0) {
+      if (deps == null) {
         continue;
       } else if (deps.length === 1) {
         temporaries.set(phi.place.identifier.id, deps[0]!);
       } else {
         temporaries.set(phi.place.identifier.id, {
-          kind: 'Aggregate',
+          kind: 'Function',
           dependencies: new Set(deps),
         });
       }
@@ -644,6 +482,9 @@ function collectDependencies(
         }
         case 'LoadContext':
         case 'LoadLocal': {
+          if (locals.has(value.place.identifier.id)) {
+            break;
+          }
           const temp = temporaries.get(value.place.identifier.id);
           if (temp != null) {
             if (temp.kind === 'Local') {
@@ -652,9 +493,6 @@ function collectDependencies(
             } else {
               temporaries.set(lvalue.identifier.id, temp);
             }
-            if (locals.has(value.place.identifier.id)) {
-              locals.add(lvalue.identifier.id);
-            }
           }
           break;
         }
@@ -790,55 +628,10 @@ function collectDependencies(
           }
           break;
         }
-        case 'ArrayExpression': {
-          const arrayDeps: Set<InferredDependency> = new Set();
-          for (const item of value.elements) {
-            if (item.kind === 'Hole') {
-              continue;
-            }
-            const place = item.kind === 'Identifier' ? item : item.place;
-            // Visit with alternative deps/locals to record manual dependencies
-            visitCandidateDependency(place, temporaries, arrayDeps, new Set());
-            // Visit normally to propagate inferred dependencies upward
-            visit(place);
-          }
-          temporaries.set(lvalue.identifier.id, {
-            kind: 'Aggregate',
-            dependencies: arrayDeps,
-            loc: value.loc,
-          });
-          break;
-        }
-        case 'CallExpression':
         case 'MethodCall': {
-          const receiver =
-            value.kind === 'CallExpression' ? value.callee : value.property;
-
-          const onEffect = callbacks?.onEffect;
-          if (onEffect != null && isEffectHook(receiver.identifier)) {
-            const [fn, deps] = value.args;
-            if (fn?.kind === 'Identifier' && deps?.kind === 'Identifier') {
-              const fnDeps = temporaries.get(fn.identifier.id);
-              const manualDeps = temporaries.get(deps.identifier.id);
-              if (
-                fnDeps?.kind === 'Aggregate' &&
-                manualDeps?.kind === 'Aggregate'
-              ) {
-                onEffect(
-                  fnDeps.dependencies,
-                  manualDeps.dependencies,
-                  manualDeps.loc ?? null,
-                );
-              }
-            }
-          }
-
           // Ignore the method itself
           for (const operand of eachInstructionValueOperand(value)) {
-            if (
-              value.kind === 'MethodCall' &&
-              operand.identifier.id === value.property.identifier.id
-            ) {
+            if (operand.identifier.id === value.property.identifier.id) {
               continue;
             }
             visit(operand);
@@ -862,7 +655,7 @@ function collectDependencies(
       visit(operand);
     }
   }
-  return {kind: 'Aggregate', dependencies};
+  return {kind: 'Function', dependencies};
 }
 
 function printInferredDependency(dep: InferredDependency): string {
@@ -900,7 +693,7 @@ function printManualMemoDependency(dep: ManualMemoDependency): string {
 
 function isEqualTemporary(a: Temporary, b: Temporary): boolean {
   switch (a.kind) {
-    case 'Aggregate': {
+    case 'Function': {
       return false;
     }
     case 'Global': {
@@ -925,11 +718,7 @@ type Temporary =
       context: boolean;
       loc: SourceLocation;
     }
-  | {
-      kind: 'Aggregate';
-      dependencies: Set<InferredDependency>;
-      loc?: SourceLocation;
-    };
+  | {kind: 'Function'; dependencies: Set<Temporary>};
 type InferredDependency = Extract<Temporary, {kind: 'Local' | 'Global'}>;
 
 function collectReactiveIdentifiersHIR(fn: HIRFunction): Set<IdentifierId> {
@@ -1033,75 +822,3 @@ export function findOptionalPlaces(
   }
   return optionals;
 }
-
-function isOptionalDependency(
-  inferredDependency: Extract<InferredDependency, {kind: 'Local'}>,
-  reactive: Set<IdentifierId>,
-): boolean {
-  return (
-    !reactive.has(inferredDependency.identifier.id) &&
-    (isStableType(inferredDependency.identifier) ||
-      isPrimitiveType(inferredDependency.identifier))
-  );
-}
-
-function createDiagnostic(
-  category:
-    | ErrorCategory.MemoDependencies
-    | ErrorCategory.EffectExhaustiveDependencies,
-  missing: Array<InferredDependency>,
-  extra: Array<ManualMemoDependency>,
-  suggestion: CompilerSuggestion | null,
-): CompilerDiagnostic {
-  let reason: string;
-  let description: string;
-
-  function joinMissingExtraDetail(
-    missingString: string,
-    extraString: string,
-    joinStr: string,
-  ): string {
-    return [
-      missing.length !== 0 ? missingString : null,
-      extra.length !== 0 ? extraString : null,
-    ]
-      .filter(Boolean)
-      .join(joinStr);
-  }
-
-  switch (category) {
-    case ErrorCategory.MemoDependencies: {
-      reason = `Found ${joinMissingExtraDetail('missing', 'extra', '/')} memoization dependencies`;
-      description = joinMissingExtraDetail(
-        'Missing dependencies can cause a value to update less often than it should, resulting in stale UI',
-        'Extra dependencies can cause a value to update more often than it should, resulting in performance' +
-          ' problems such as excessive renders or effects firing too often',
-        '. ',
-      );
-      break;
-    }
-    case ErrorCategory.EffectExhaustiveDependencies: {
-      reason = `Found ${joinMissingExtraDetail('missing', 'extra', '/')} effect dependencies`;
-      description = joinMissingExtraDetail(
-        'Missing dependencies can cause an effect to fire less often than it should',
-        'Extra dependencies can cause an effect to fire more often than it should, resulting' +
-          ' in performance problems such as excessive renders and side effects',
-        '. ',
-      );
-      break;
-    }
-    default: {
-      CompilerError.simpleInvariant(false, {
-        reason: `Unexpected error category: ${category}`,
-        loc: GeneratedSource,
-      });
-    }
-  }
-
-  return CompilerDiagnostic.create({
-    category,
-    reason,
-    description,
-    suggestions: suggestion != null ? [suggestion] : null,
-  });
-}

compiler/packages/babel-plugin-react-compiler/src/Validation/ValidateNoSetStateInEffects.ts

@@ -16,7 +16,6 @@ import {
   IdentifierId,
   isSetStateType,
   isUseEffectHookType,
-  isUseEffectEventType,
   isUseInsertionEffectHookType,
   isUseLayoutEffectHookType,
   isUseRefType,
@@ -99,20 +98,7 @@ export function validateNoSetStateInEffects(
             instr.value.kind === 'MethodCall'
               ? instr.value.receiver
               : instr.value.callee;
-
-          if (isUseEffectEventType(callee.identifier)) {
-            const arg = instr.value.args[0];
-            if (arg !== undefined && arg.kind === 'Identifier') {
-              const setState = setStateFunctions.get(arg.identifier.id);
-              if (setState !== undefined) {
-                /**
-                 * This effect event function calls setState synchonously,
-                 * treat it as a setState function for transitive tracking
-                 */
-                setStateFunctions.set(instr.lvalue.identifier.id, setState);
-              }
-            }
-          } else if (
+          if (
             isUseEffectHookType(callee.identifier) ||
             isUseLayoutEffectHookType(callee.identifier) ||
             isUseInsertionEffectHookType(callee.identifier)
@@ -121,58 +107,26 @@ export function validateNoSetStateInEffects(
             if (arg !== undefined && arg.kind === 'Identifier') {
               const setState = setStateFunctions.get(arg.identifier.id);
               if (setState !== undefined) {
-                const enableVerbose =
-                  env.config.enableVerboseNoSetStateInEffect;
-                if (enableVerbose) {
-                  errors.pushDiagnostic(
-                    CompilerDiagnostic.create({
-                      category: ErrorCategory.EffectSetState,
-                      reason:
-                        'Calling setState synchronously within an effect can trigger cascading renders',
-                      description:
-                        'Effects are intended to synchronize state between React and external systems. ' +
-                        'Calling setState synchronously causes cascading renders that hurt performance.\n\n' +
-                        'This pattern may indicate one of several issues:\n\n' +
-                        '**1. Non-local derived data**: If the value being set could be computed from props/state ' +
-                        'but requires data from a parent component, consider restructuring state ownership so the ' +
-                        'derivation can happen during render in the component that owns the relevant state.\n\n' +
-                        "**2. Derived event pattern**: If you're detecting when a prop changes (e.g., `isPlaying` " +
-                        'transitioning from false to true), this often indicates the parent should provide an event ' +
-                        'callback (like `onPlay`) instead of just the current state. Request access to the original event.\n\n' +
-                        "**3. Force update / external sync**: If you're forcing a re-render to sync with an external " +
-                        'data source (mutable values outside React), use `useSyncExternalStore` to properly subscribe ' +
-                        'to external state changes.\n\n' +
-                        'See: https://react.dev/learn/you-might-not-need-an-effect',
-                      suggestions: null,
-                    }).withDetails({
-                      kind: 'error',
-                      loc: setState.loc,
-                      message:
-                        'Avoid calling setState() directly within an effect',
-                    }),
-                  );
-                } else {
-                  errors.pushDiagnostic(
-                    CompilerDiagnostic.create({
-                      category: ErrorCategory.EffectSetState,
-                      reason:
-                        'Calling setState synchronously within an effect can trigger cascading renders',
-                      description:
-                        'Effects are intended to synchronize state between React and external systems such as manually updating the DOM, state management libraries, or other platform APIs. ' +
-                        'In general, the body of an effect should do one or both of the following:\n' +
-                        '* Update external systems with the latest state from React.\n' +
-                        '* Subscribe for updates from some external system, calling setState in a callback function when external state changes.\n\n' +
-                        'Calling setState synchronously within an effect body causes cascading renders that can hurt performance, and is not recommended. ' +
-                        '(https://react.dev/learn/you-might-not-need-an-effect)',
-                      suggestions: null,
-                    }).withDetails({
-                      kind: 'error',
-                      loc: setState.loc,
-                      message:
-                        'Avoid calling setState() directly within an effect',
-                    }),
-                  );
-                }
+                errors.pushDiagnostic(
+                  CompilerDiagnostic.create({
+                    category: ErrorCategory.EffectSetState,
+                    reason:
+                      'Calling setState synchronously within an effect can trigger cascading renders',
+                    description:
+                      'Effects are intended to synchronize state between React and external systems such as manually updating the DOM, state management libraries, or other platform APIs. ' +
+                      'In general, the body of an effect should do one or both of the following:\n' +
+                      '* Update external systems with the latest state from React.\n' +
+                      '* Subscribe for updates from some external system, calling setState in a callback function when external state changes.\n\n' +
+                      'Calling setState synchronously within an effect body causes cascading renders that can hurt performance, and is not recommended. ' +
+                      '(https://react.dev/learn/you-might-not-need-an-effect)',
+                    suggestions: null,
+                  }).withDetails({
+                    kind: 'error',
+                    loc: setState.loc,
+                    message:
+                      'Avoid calling setState() directly within an effect',
+                  }),
+                );
               }
             }
           }

compiler/packages/babel-plugin-react-compiler/src/Validation/ValidateNoSetStateInRender.ts

@@ -155,40 +155,20 @@ function validateNoSetStateInRenderImpl(
                 }),
               );
             } else if (unconditionalBlocks.has(block.id)) {
-              const enableUseKeyedState = fn.env.config.enableUseKeyedState;
-              if (enableUseKeyedState) {
-                errors.pushDiagnostic(
-                  CompilerDiagnostic.create({
-                    category: ErrorCategory.RenderSetState,
-                    reason: 'Cannot call setState during render',
-                    description:
-                      'Calling setState during render may trigger an infinite loop.\n' +
-                      '* To reset state when other state/props change, use `const [state, setState] = useKeyedState(initialState, key)` to reset `state` when `key` changes.\n' +
-                      '* To derive data from other state/props, compute the derived data during render without using state',
-                    suggestions: null,
-                  }).withDetails({
-                    kind: 'error',
-                    loc: callee.loc,
-                    message: 'Found setState() in render',
-                  }),
-                );
-              } else {
-                errors.pushDiagnostic(
-                  CompilerDiagnostic.create({
-                    category: ErrorCategory.RenderSetState,
-                    reason: 'Cannot call setState during render',
-                    description:
-                      'Calling setState during render may trigger an infinite loop.\n' +
-                      '* To reset state when other state/props change, store the previous value in state and update conditionally: https://react.dev/reference/react/useState#storing-information-from-previous-renders\n' +
-                      '* To derive data from other state/props, compute the derived data during render without using state',
-                    suggestions: null,
-                  }).withDetails({
-                    kind: 'error',
-                    loc: callee.loc,
-                    message: 'Found setState() in render',
-                  }),
-                );
-              }
+              errors.pushDiagnostic(
+                CompilerDiagnostic.create({
+                  category: ErrorCategory.RenderSetState,
+                  reason:
+                    'Calling setState during render may trigger an infinite loop',
+                  description:
+                    'Calling setState during render will trigger another render, and can lead to infinite loops. (https://react.dev/reference/react/useState)',
+                  suggestions: null,
+                }).withDetails({
+                  kind: 'error',
+                  loc: callee.loc,
+                  message: 'Found setState() in render',
+                }),
+              );
             }
           }
           break;

compiler/packages/babel-plugin-react-compiler/src/Validation/ValidatePreservedManualMemoization.ts

@@ -242,7 +242,6 @@ function validateInferredDep(
     normalizedDep = {
       root: maybeNormalizedRoot.root,
       path: [...maybeNormalizedRoot.path, ...dep.path],
-      loc: maybeNormalizedRoot.loc,
     };
   } else {
     CompilerError.invariant(dep.identifier.name?.kind === 'named', {
@@ -268,10 +267,8 @@ function validateInferredDep(
           effect: Effect.Read,
           reactive: false,
         },
-        constant: false,
       },
       path: [...dep.path],
-      loc: GeneratedSource,
     };
   }
   for (const decl of declsWithinMemoBlock) {
@@ -382,10 +379,8 @@ class Visitor extends ReactiveFunctionVisitor<VisitorState> {
                 root: {
                   kind: 'NamedLocal',
                   value: storeTarget,
-                  constant: false,
                 },
                 path: [],
-                loc: storeTarget.loc,
               });
             }
           }
@@ -413,10 +408,8 @@ class Visitor extends ReactiveFunctionVisitor<VisitorState> {
         root: {
           kind: 'NamedLocal',
           value: {...lvalue},
-          constant: false,
         },
         path: [],
-        loc: lvalue.loc,
       });
     }
   }

compiler/packages/babel-plugin-react-compiler/src/Validation/ValidateSourceLocations.ts

@@ -27,11 +27,7 @@ import {Result} from '../Utils/Result';
 
 /**
  * Some common node types that are important for coverage tracking.
- * Based on istanbul-lib-instrument + some other common nodes we expect to be present in the generated AST.
- *
- * Note: For VariableDeclaration, VariableDeclarator, and Identifier, we enforce stricter validation
- * that requires both the source location AND node type to match in the generated AST. This ensures
- * that variable declarations maintain their structural integrity through compilation.
+ * Based on istanbul-lib-instrument
  */
 const IMPORTANT_INSTRUMENTED_TYPES = new Set([
   'ArrowFunctionExpression',
@@ -58,14 +54,6 @@ const IMPORTANT_INSTRUMENTED_TYPES = new Set([
   'LabeledStatement',
   'ConditionalExpression',
   'LogicalExpression',
-
-  /**
-   * Note: these aren't important for coverage tracking,
-   * but we still want to track them to ensure we aren't regressing them when
-   * we fix the source location tracking for other nodes.
-   */
-  'VariableDeclaration',
-  'Identifier',
 ]);
 
 /**
@@ -126,13 +114,10 @@ export function validateSourceLocations(
 ): Result<void, CompilerError> {
   const errors = new CompilerError();
 
-  /*
-   * Step 1: Collect important locations from the original source
-   * Note: Multiple node types can share the same location (e.g. VariableDeclarator and Identifier)
-   */
+  // Step 1: Collect important locations from the original source
   const importantOriginalLocations = new Map<
     string,
-    {loc: t.SourceLocation; nodeTypes: Set<string>}
+    {loc: t.SourceLocation; nodeType: string}
   >();
 
   func.traverse({
@@ -152,31 +137,20 @@ export function validateSourceLocations(
       // Collect the location if it exists
       if (node.loc) {
         const key = locationKey(node.loc);
-        const existing = importantOriginalLocations.get(key);
-        if (existing) {
-          existing.nodeTypes.add(node.type);
-        } else {
-          importantOriginalLocations.set(key, {
-            loc: node.loc,
-            nodeTypes: new Set([node.type]),
-          });
-        }
+        importantOriginalLocations.set(key, {
+          loc: node.loc,
+          nodeType: node.type,
+        });
       }
     },
   });
 
-  // Step 2: Collect all locations from the generated AST with their node types
-  const generatedLocations = new Map<string, Set<string>>();
+  // Step 2: Collect all locations from the generated AST
+  const generatedLocations = new Set<string>();
 
   function collectGeneratedLocations(node: t.Node): void {
     if (node.loc) {
-      const key = locationKey(node.loc);
-      const nodeTypes = generatedLocations.get(key);
-      if (nodeTypes) {
-        nodeTypes.add(node.type);
-      } else {
-        generatedLocations.set(key, new Set([node.type]));
-      }
+      generatedLocations.add(locationKey(node.loc));
     }
 
     // Use Babel's VISITOR_KEYS to traverse only actual node properties
@@ -209,86 +183,22 @@ export function validateSourceLocations(
     collectGeneratedLocations(outlined.fn.body);
   }
 
-  /*
-   * Step 3: Validate that all important locations are preserved
-   * For certain node types, also validate that the node type matches
-   */
-  const strictNodeTypes = new Set([
-    'VariableDeclaration',
-    'VariableDeclarator',
-    'Identifier',
-  ]);
-
-  const reportMissingLocation = (
-    loc: t.SourceLocation,
-    nodeType: string,
-  ): void => {
-    errors.pushDiagnostic(
-      CompilerDiagnostic.create({
-        category: ErrorCategory.Todo,
-        reason: 'Important source location missing in generated code',
-        description:
-          `Source location for ${nodeType} is missing in the generated output. This can cause coverage instrumentation ` +
-          `to fail to track this code properly, resulting in inaccurate coverage reports.`,
-      }).withDetails({
-        kind: 'error',
-        loc,
-        message: null,
-      }),
-    );
-  };
-
-  const reportWrongNodeType = (
-    loc: t.SourceLocation,
-    expectedType: string,
-    actualTypes: Set<string>,
-  ): void => {
-    errors.pushDiagnostic(
-      CompilerDiagnostic.create({
-        category: ErrorCategory.Todo,
-        reason:
-          'Important source location has wrong node type in generated code',
-        description:
-          `Source location for ${expectedType} exists in the generated output but with wrong node type(s): ${Array.from(actualTypes).join(', ')}. ` +
-          `This can cause coverage instrumentation to fail to track this code properly, resulting in inaccurate coverage reports.`,
-      }).withDetails({
-        kind: 'error',
-        loc,
-        message: null,
-      }),
-    );
-  };
-
-  for (const [key, {loc, nodeTypes}] of importantOriginalLocations) {
-    const generatedNodeTypes = generatedLocations.get(key);
-
-    if (!generatedNodeTypes) {
-      // Location is completely missing
-      reportMissingLocation(loc, Array.from(nodeTypes).join(', '));
-    } else {
-      // Location exists, check each node type
-      for (const nodeType of nodeTypes) {
-        if (
-          strictNodeTypes.has(nodeType) &&
-          !generatedNodeTypes.has(nodeType)
-        ) {
-          /*
-           * For strict node types, the specific node type must be present
-           * Check if any generated node type is also an important original node type
-           */
-          const hasValidNodeType = Array.from(generatedNodeTypes).some(
-            genType => nodeTypes.has(genType),
-          );
-
-          if (hasValidNodeType) {
-            // At least one generated node type is valid (also in original), so this is just missing
-            reportMissingLocation(loc, nodeType);
-          } else {
-            // None of the generated node types are in original - this is wrong node type
-            reportWrongNodeType(loc, nodeType, generatedNodeTypes);
-          }
-        }
-      }
+  // Step 3: Validate that all important locations are preserved
+  for (const [key, {loc, nodeType}] of importantOriginalLocations) {
+    if (!generatedLocations.has(key)) {
+      errors.pushDiagnostic(
+        CompilerDiagnostic.create({
+          category: ErrorCategory.Todo,
+          reason: 'Important source location missing in generated code',
+          description:
+            `Source location for ${nodeType} is missing in the generated output. This can cause coverage instrumentation ` +
+            `to fail to track this code properly, resulting in inaccurate coverage reports.`,
+        }).withDetails({
+          kind: 'error',
+          loc,
+          message: null,
+        }),
+      );
     }
   }
 

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/alias-capture-in-method-receiver-and-mutate.expect.md

@@ -35,8 +35,10 @@ function Component() {
   let t0;
   if ($[0] === Symbol.for("react.memo_cache_sentinel")) {
     const a = makeObject_Primitives();
+
     const x = [];
     x.push(a);
+
     mutate(x);
     t0 = [x, a];
     $[0] = t0;

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/alias-capture-in-method-receiver.expect.md

@@ -33,6 +33,7 @@ function Component() {
   if ($[1] === Symbol.for("react.memo_cache_sentinel")) {
     const x = [];
     x.push(a);
+
     t1 = [x, a];
     $[1] = t1;
   } else {

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/aliased-nested-scope-fn-expr.expect.md

@@ -85,10 +85,14 @@ function Component(t0) {
   let t1;
   if ($[0] !== prop) {
     const obj = shallowCopy(prop);
+
     const aliasedObj = identity(obj);
+
     const getId = () => obj.id;
+
     mutate(aliasedObj);
     setPropertyByKey(aliasedObj, "id", prop.id + 1);
+
     t1 = <Stringify getId={getId} shouldInvokeFns={true} />;
     $[0] = prop;
     $[1] = t1;

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/aliased-nested-scope-truncated-dep.expect.md

@@ -181,9 +181,12 @@ function Component(t0) {
   if ($[0] !== prop) {
     const obj = shallowCopy(prop);
     const aliasedObj = identity(obj);
+
     const id = [obj.id];
+
     mutate(aliasedObj);
     setPropertyByKey(aliasedObj, "id", prop.id + 1);
+
     t1 = <Stringify id={id} />;
     $[0] = prop;
     $[1] = t1;

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/align-scopes-within-nested-valueblock-in-array.expect.md

@@ -54,6 +54,7 @@ function Foo(t0) {
   let t1;
   if ($[0] !== cond1 || $[1] !== cond2) {
     const arr = makeArray({ a: 2 }, 2, []);
+
     t1 = cond1 ? (
       <>
         <div>{identity("foo")}</div>

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/allow-modify-global-in-callback-jsx.expect.md

@@ -2,7 +2,7 @@
 ## Input
 
 ```javascript
-// @enablePreserveExistingMemoizationGuarantees:false @validateExhaustiveMemoizationDependencies:false
+// @enablePreserveExistingMemoizationGuarantees:false
 import {useMemo} from 'react';
 
 const someGlobal = {value: 0};
@@ -33,7 +33,7 @@ export const FIXTURE_ENTRYPOINT = {
 ## Code
 
 ```javascript
-import { c as _c } from "react/compiler-runtime"; // @enablePreserveExistingMemoizationGuarantees:false @validateExhaustiveMemoizationDependencies:false
+import { c as _c } from "react/compiler-runtime"; // @enablePreserveExistingMemoizationGuarantees:false
 import { useMemo } from "react";
 
 const someGlobal = { value: 0 };

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/allow-modify-global-in-callback-jsx.js

@@ -1,4 +1,4 @@
-// @enablePreserveExistingMemoizationGuarantees:false @validateExhaustiveMemoizationDependencies:false
+// @enablePreserveExistingMemoizationGuarantees:false
 import {useMemo} from 'react';
 
 const someGlobal = {value: 0};

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/allow-mutating-ref-in-callback-passed-to-jsx-indirect.expect.md

@@ -49,6 +49,7 @@ function Component() {
         ref.current = "";
       }
     };
+
     t0 = () => {
       setRef();
     };

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/allow-mutating-ref-property-in-callback-passed-to-jsx-indirect.expect.md

@@ -49,6 +49,7 @@ function Component() {
         ref.current.value = "";
       }
     };
+
     t0 = () => {
       setRef();
     };

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/allow-ref-access-in-event-handler-wrapper.expect.md

@@ -74,6 +74,7 @@ function Component() {
         console.log(ref.current.value);
       }
     };
+
     t0 = (
       <>
         <input ref={ref} />

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/allow-ref-type-cast-in-render.expect.md

@@ -36,6 +36,7 @@ function useArrayOfRef() {
     const callback = (value) => {
       ref.current = value;
     };
+
     t0 = [callback];
     $[0] = t0;
   } else {

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/array-at-closure.expect.md

@@ -35,6 +35,7 @@ function Component(props) {
       const arr = [...bar(props)];
       return arr.at(x);
     };
+
     t1 = fn();
     $[2] = props;
     $[3] = x;

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/array-pattern-spread-creates-array.expect.md

@@ -2,7 +2,7 @@
 ## Input
 
 ```javascript
-// @validatePreserveExistingMemoizationGuarantees @validateExhaustiveMemoizationDependencies:false
+// @validatePreserveExistingMemoizationGuarantees
 import {useMemo} from 'react';
 import {makeObject_Primitives, ValidateMemoization} from 'shared-runtime';
 
@@ -36,7 +36,7 @@ export const FIXTURE_ENTRYPOINT = {
 ## Code
 
 ```javascript
-import { c as _c } from "react/compiler-runtime"; // @validatePreserveExistingMemoizationGuarantees @validateExhaustiveMemoizationDependencies:false
+import { c as _c } from "react/compiler-runtime"; // @validatePreserveExistingMemoizationGuarantees
 import { useMemo } from "react";
 import { makeObject_Primitives, ValidateMemoization } from "shared-runtime";
 

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/array-pattern-spread-creates-array.js

@@ -1,4 +1,4 @@
-// @validatePreserveExistingMemoizationGuarantees @validateExhaustiveMemoizationDependencies:false
+// @validatePreserveExistingMemoizationGuarantees
 import {useMemo} from 'react';
 import {makeObject_Primitives, ValidateMemoization} from 'shared-runtime';
 

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/array-spread-mutable-iterator.expect.md

@@ -61,6 +61,7 @@ function useBar(t0) {
   if ($[0] !== arg) {
     const s = new Set([1, 5, 4]);
     const mutableIterator = s.values();
+
     t1 = [arg, ...mutableIterator];
     $[0] = arg;
     $[1] = t1;

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/block-scoping-switch-variable-scoping.expect.md

@@ -2,7 +2,6 @@
 ## Input
 
 ```javascript
-// @validateExhaustiveMemoizationDependencies:false
 import {useMemo} from 'react';
 
 function Component(props) {
@@ -31,7 +30,7 @@ export const FIXTURE_ENTRYPOINT = {
 ## Code
 
 ```javascript
-import { c as _c } from "react/compiler-runtime"; // @validateExhaustiveMemoizationDependencies:false
+import { c as _c } from "react/compiler-runtime";
 import { useMemo } from "react";
 
 function Component(props) {

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/block-scoping-switch-variable-scoping.js

@@ -1,4 +1,3 @@
-// @validateExhaustiveMemoizationDependencies:false
 import {useMemo} from 'react';
 
 function Component(props) {

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/call.expect.md

@@ -28,6 +28,7 @@ function Component(props) {
     const a = [];
     const b = {};
     foo(a, b);
+
     foo(b);
     t0 = <div a={a} b={b} />;
     $[0] = t0;

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/capture-ref-for-later-mutation.expect.md

@@ -45,6 +45,7 @@ function useKeyCommand() {
       const nextPosition = direction === "left" ? addOne(position) : position;
       currentPosition.current = nextPosition;
     };
+
     const moveLeft = { handler: handleKey("left") };
     const moveRight = { handler: handleKey("right") };
     t0 = [moveLeft, moveRight];

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/capturing-func-mutate.expect.md

@@ -45,6 +45,7 @@ function Component(t0) {
       z.a = 2;
       mutate(y.b);
     };
+
     x();
     t1 = [y, z];
     $[0] = a;

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/class-component-with-render-helper.expect.md

@@ -2,7 +2,7 @@
 ## Input
 
 ```javascript
-// @expectNothingCompiled @compilationMode:"infer"
+// @compilationMode:"infer"
 class Component {
   _renderMessage = () => {
     const Message = () => {
@@ -22,7 +22,7 @@ class Component {
 ## Code
 
 ```javascript
-// @expectNothingCompiled @compilationMode:"infer"
+// @compilationMode:"infer"
 class Component {
   _renderMessage = () => {
     const Message = () => {

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/class-component-with-render-helper.js

@@ -1,4 +1,4 @@
-// @expectNothingCompiled @compilationMode:"infer"
+// @compilationMode:"infer"
 class Component {
   _renderMessage = () => {
     const Message = () => {

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/codegen-emit-make-read-only.expect.md

@@ -29,6 +29,7 @@ function MyComponentName(props) {
     const x = {};
     foo(x, props.a);
     foo(x, props.b);
+
     y = [];
     y.push(x);
     $[0] = props.a;

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/codegen-inline-iife-reassign.expect.md

@@ -34,6 +34,7 @@ function useTest() {
   let t0;
   if ($[0] === Symbol.for("react.memo_cache_sentinel")) {
     let w = {};
+
     const t1 = (w = 42);
     const t2 = w;
 

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/codegen-inline-iife-storeprop.expect.md

@@ -34,6 +34,7 @@ function useTest() {
   let t0;
   if ($[0] === Symbol.for("react.memo_cache_sentinel")) {
     const w = {};
+
     const t1 = (w.x = 42);
     const t2 = w.x;
 

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/conditional-on-mutable.expect.md

@@ -44,9 +44,11 @@ function ComponentA(props) {
     if (b) {
       a.push(props.p0);
     }
+
     if (props.p1) {
       b.push(props.p2);
     }
+
     t0 = <Foo a={a} b={b} />;
     $[0] = props.p0;
     $[1] = props.p1;
@@ -67,9 +69,11 @@ function ComponentB(props) {
     if (mayMutate(b)) {
       a.push(props.p0);
     }
+
     if (props.p1) {
       b.push(props.p2);
     }
+
     t0 = <Foo a={a} b={b} />;
     $[0] = props.p0;
     $[1] = props.p1;

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/constructor.expect.md

@@ -28,6 +28,7 @@ function Component(props) {
     const a = [];
     const b = {};
     new Foo(a, b);
+
     new Foo(b);
     t0 = <div a={a} b={b} />;
     $[0] = t0;

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/context-variable-as-jsx-element-tag.expect.md

@@ -11,7 +11,7 @@ function Component(props) {
 
   Component = useMemo(() => {
     return Component;
-  }, [Component]);
+  });
 
   return <Component {...props} />;
 }
@@ -36,7 +36,6 @@ function Component(props) {
   if ($[0] === Symbol.for("react.memo_cache_sentinel")) {
     Component = Stringify;
 
-    Component;
     Component = Component;
     $[0] = Component;
   } else {

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/context-variable-as-jsx-element-tag.js

@@ -7,7 +7,7 @@ function Component(props) {
 
   Component = useMemo(() => {
     return Component;
-  }, [Component]);
+  });
 
   return <Component {...props} />;
 }

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/context-variable-reassigned-outside-of-lambda.expect.md

@@ -34,6 +34,7 @@ function Component(props) {
     const callback = () => {
       console.log(x);
     };
+
     x = {};
     t0 = <Stringify callback={callback} shouldInvokeFns={true} />;
     $[0] = t0;

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/custom-opt-out-directive.expect.md

@@ -2,7 +2,7 @@
 ## Input
 
 ```javascript
-// @expectNothingCompiled @customOptOutDirectives:["use todo memo"]
+// @customOptOutDirectives:["use todo memo"]
 function Component() {
   'use todo memo';
   return <div>hello world!</div>;
@@ -18,7 +18,7 @@ export const FIXTURE_ENTRYPOINT = {
 ## Code
 
 ```javascript
-// @expectNothingCompiled @customOptOutDirectives:["use todo memo"]
+// @customOptOutDirectives:["use todo memo"]
 function Component() {
   "use todo memo";
   return <div>hello world!</div>;

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/custom-opt-out-directive.tsx

@@ -1,4 +1,4 @@
-// @expectNothingCompiled @customOptOutDirectives:["use todo memo"]
+// @customOptOutDirectives:["use todo memo"]
 function Component() {
   'use todo memo';
   return <div>hello world!</div>;

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/destructuring-mixed-scope-and-local-variables-with-default.expect.md

@@ -75,6 +75,7 @@ function Component(props) {
   let t0;
   if ($[0] !== post) {
     const allUrls = [];
+
     const { media: t1, comments: t2, urls: t3 } = post;
     const media = t1 === undefined ? null : t1;
     let t4;
@@ -101,6 +102,7 @@ function Component(props) {
         if (!comments.length) {
           return;
         }
+
         console.log(comments.length);
       };
       $[6] = comments.length;
@@ -109,6 +111,7 @@ function Component(props) {
       t6 = $[7];
     }
     const onClick = t6;
+
     allUrls.push(...urls);
     t0 = <Stringify media={media} allUrls={allUrls} onClick={onClick} />;
     $[0] = post;

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/destructuring-mixed-scope-declarations-and-locals.expect.md

@@ -53,6 +53,7 @@ function Component(props) {
   let t0;
   if ($[0] !== post) {
     const allUrls = [];
+
     const { media, comments, urls } = post;
     let t1;
     if ($[2] !== comments.length) {
@@ -60,6 +61,7 @@ function Component(props) {
         if (!comments.length) {
           return;
         }
+
         console.log(comments.length);
       };
       $[2] = comments.length;
@@ -68,6 +70,7 @@ function Component(props) {
       t1 = $[3];
     }
     const onClick = t1;
+
     allUrls.push(...urls);
     t0 = <Media media={media} onClick={onClick} />;
     $[0] = post;

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/dont-memoize-primitive-function-call-non-escaping.expect.md

@@ -2,7 +2,7 @@
 ## Input
 
 ```javascript
-// @expectNothingCompiled @compilationMode:"infer" @enablePreserveExistingMemoizationGuarantees @validatePreserveExistingMemoizationGuarantees
+// @compilationMode:"infer" @enablePreserveExistingMemoizationGuarantees @validatePreserveExistingMemoizationGuarantees
 import {useMemo} from 'react';
 import {makeObject_Primitives, ValidateMemoization} from 'shared-runtime';
 
@@ -37,7 +37,7 @@ export const FIXTURE_ENTRYPOINT = {
 ## Code
 
 ```javascript
-// @expectNothingCompiled @compilationMode:"infer" @enablePreserveExistingMemoizationGuarantees @validatePreserveExistingMemoizationGuarantees
+// @compilationMode:"infer" @enablePreserveExistingMemoizationGuarantees @validatePreserveExistingMemoizationGuarantees
 import { useMemo } from "react";
 import { makeObject_Primitives, ValidateMemoization } from "shared-runtime";
 

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/dont-memoize-primitive-function-call-non-escaping.js

@@ -1,4 +1,4 @@
-// @expectNothingCompiled @compilationMode:"infer" @enablePreserveExistingMemoizationGuarantees @validatePreserveExistingMemoizationGuarantees
+// @compilationMode:"infer" @enablePreserveExistingMemoizationGuarantees @validatePreserveExistingMemoizationGuarantees
 import {useMemo} from 'react';
 import {makeObject_Primitives, ValidateMemoization} from 'shared-runtime';
 

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/dont-merge-if-dep-is-inner-declaration-of-previous-scope.expect.md

@@ -57,6 +57,7 @@ function Component(t0) {
   let y;
   if ($[0] !== a || $[1] !== b || $[2] !== c) {
     x = [];
+
     if (a) {
       let t1;
       if ($[5] !== b) {

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/effect-derived-computations/derived-state-conditionally-in-effect.expect.md

@@ -2,7 +2,7 @@
 ## Input
 
 ```javascript
-// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly @outputMode:"lint"
+// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly
 import {useEffect, useState} from 'react';
 
 function Component({value, enabled}) {
@@ -29,21 +29,43 @@ export const FIXTURE_ENTRYPOINT = {
 ## Code
 
 ```javascript
-// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly @outputMode:"lint"
+import { c as _c } from "react/compiler-runtime"; // @validateNoDerivedComputationsInEffects_exp @loggerTestOnly
 import { useEffect, useState } from "react";
 
-function Component({ value, enabled }) {
+function Component(t0) {
+  const $ = _c(6);
+  const { value, enabled } = t0;
   const [localValue, setLocalValue] = useState("");
+  let t1;
+  let t2;
+  if ($[0] !== enabled || $[1] !== value) {
+    t1 = () => {
+      if (enabled) {
+        setLocalValue(value);
+      } else {
+        setLocalValue("disabled");
+      }
+    };
 
-  useEffect(() => {
-    if (enabled) {
-      setLocalValue(value);
-    } else {
-      setLocalValue("disabled");
-    }
-  }, [value, enabled]);
-
-  return <div>{localValue}</div>;
+    t2 = [value, enabled];
+    $[0] = enabled;
+    $[1] = value;
+    $[2] = t1;
+    $[3] = t2;
+  } else {
+    t1 = $[2];
+    t2 = $[3];
+  }
+  useEffect(t1, t2);
+  let t3;
+  if ($[4] !== localValue) {
+    t3 = <div>{localValue}</div>;
+    $[4] = localValue;
+    $[5] = t3;
+  } else {
+    t3 = $[5];
+  }
+  return t3;
 }
 
 export const FIXTURE_ENTRYPOINT = {
@@ -56,8 +78,8 @@ export const FIXTURE_ENTRYPOINT = {
 ## Logs
 
 ```
-{"kind":"CompileError","detail":{"options":{"description":"Using an effect triggers an additional render which can hurt performance and user experience, potentially briefly showing stale values to the user\n\nThis setState call is setting a derived value that depends on the following reactive sources:\n\nProps: [value]\n\nData Flow Tree:\n└── value (Prop)\n\nSee: https://react.dev/learn/you-might-not-need-an-effect#updating-state-based-on-props-or-state","category":"EffectDerivationsOfState","reason":"You might not need an effect. Derive values in render, not effects.","details":[{"kind":"error","loc":{"start":{"line":9,"column":6,"index":263},"end":{"line":9,"column":19,"index":276},"filename":"derived-state-conditionally-in-effect.ts","identifierName":"setLocalValue"},"message":"This should be computed during render, not in an effect"}]}},"fnLoc":null}
-{"kind":"CompileSuccess","fnLoc":{"start":{"line":4,"column":0,"index":126},"end":{"line":16,"column":1,"index":397},"filename":"derived-state-conditionally-in-effect.ts"},"fnName":"Component","memoSlots":6,"memoBlocks":2,"memoValues":3,"prunedMemoBlocks":0,"prunedMemoValues":0}
+{"kind":"CompileError","detail":{"options":{"description":"Using an effect triggers an additional render which can hurt performance and user experience, potentially briefly showing stale values to the user\n\nThis setState call is setting a derived value that depends on the following reactive sources:\n\nProps: [value]\n\nData Flow Tree:\n└── value (Prop)\n\nSee: https://react.dev/learn/you-might-not-need-an-effect#updating-state-based-on-props-or-state","category":"EffectDerivationsOfState","reason":"You might not need an effect. Derive values in render, not effects.","details":[{"kind":"error","loc":{"start":{"line":9,"column":6,"index":244},"end":{"line":9,"column":19,"index":257},"filename":"derived-state-conditionally-in-effect.ts","identifierName":"setLocalValue"},"message":"This should be computed during render, not in an effect"}]}},"fnLoc":null}
+{"kind":"CompileSuccess","fnLoc":{"start":{"line":4,"column":0,"index":107},"end":{"line":16,"column":1,"index":378},"filename":"derived-state-conditionally-in-effect.ts"},"fnName":"Component","memoSlots":6,"memoBlocks":2,"memoValues":3,"prunedMemoBlocks":0,"prunedMemoValues":0}
 ```
       
 ### Eval output

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/effect-derived-computations/derived-state-conditionally-in-effect.js

@@ -1,4 +1,4 @@
-// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly @outputMode:"lint"
+// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly
 import {useEffect, useState} from 'react';
 
 function Component({value, enabled}) {

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/effect-derived-computations/derived-state-from-default-props.expect.md

@@ -2,7 +2,7 @@
 ## Input
 
 ```javascript
-// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly @outputMode:"lint"
+// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly
 import {useEffect, useState} from 'react';
 
 export default function Component({input = 'empty'}) {
@@ -26,18 +26,38 @@ export const FIXTURE_ENTRYPOINT = {
 ## Code
 
 ```javascript
-// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly @outputMode:"lint"
+import { c as _c } from "react/compiler-runtime"; // @validateNoDerivedComputationsInEffects_exp @loggerTestOnly
 import { useEffect, useState } from "react";
 
-export default function Component({ input = "empty" }) {
+export default function Component(t0) {
+  const $ = _c(5);
+  const { input: t1 } = t0;
+  const input = t1 === undefined ? "empty" : t1;
   const [currInput, setCurrInput] = useState(input);
-  const localConst = "local const";
-
-  useEffect(() => {
-    setCurrInput(input + localConst);
-  }, [input, localConst]);
-
-  return <div>{currInput}</div>;
+  let t2;
+  let t3;
+  if ($[0] !== input) {
+    t2 = () => {
+      setCurrInput(input + "local const");
+    };
+    t3 = [input, "local const"];
+    $[0] = input;
+    $[1] = t2;
+    $[2] = t3;
+  } else {
+    t2 = $[1];
+    t3 = $[2];
+  }
+  useEffect(t2, t3);
+  let t4;
+  if ($[3] !== currInput) {
+    t4 = <div>{currInput}</div>;
+    $[3] = currInput;
+    $[4] = t4;
+  } else {
+    t4 = $[4];
+  }
+  return t4;
 }
 
 export const FIXTURE_ENTRYPOINT = {
@@ -50,8 +70,8 @@ export const FIXTURE_ENTRYPOINT = {
 ## Logs
 
 ```
-{"kind":"CompileError","detail":{"options":{"description":"Using an effect triggers an additional render which can hurt performance and user experience, potentially briefly showing stale values to the user\n\nThis setState call is setting a derived value that depends on the following reactive sources:\n\nProps: [input]\n\nData Flow Tree:\n└── input (Prop)\n\nSee: https://react.dev/learn/you-might-not-need-an-effect#updating-state-based-on-props-or-state","category":"EffectDerivationsOfState","reason":"You might not need an effect. Derive values in render, not effects.","details":[{"kind":"error","loc":{"start":{"line":9,"column":4,"index":295},"end":{"line":9,"column":16,"index":307},"filename":"derived-state-from-default-props.ts","identifierName":"setCurrInput"},"message":"This should be computed during render, not in an effect"}]}},"fnLoc":null}
-{"kind":"CompileSuccess","fnLoc":{"start":{"line":4,"column":15,"index":141},"end":{"line":13,"column":1,"index":391},"filename":"derived-state-from-default-props.ts"},"fnName":"Component","memoSlots":5,"memoBlocks":2,"memoValues":3,"prunedMemoBlocks":0,"prunedMemoValues":0}
+{"kind":"CompileError","detail":{"options":{"description":"Using an effect triggers an additional render which can hurt performance and user experience, potentially briefly showing stale values to the user\n\nThis setState call is setting a derived value that depends on the following reactive sources:\n\nProps: [input]\n\nData Flow Tree:\n└── input (Prop)\n\nSee: https://react.dev/learn/you-might-not-need-an-effect#updating-state-based-on-props-or-state","category":"EffectDerivationsOfState","reason":"You might not need an effect. Derive values in render, not effects.","details":[{"kind":"error","loc":{"start":{"line":9,"column":4,"index":276},"end":{"line":9,"column":16,"index":288},"filename":"derived-state-from-default-props.ts","identifierName":"setCurrInput"},"message":"This should be computed during render, not in an effect"}]}},"fnLoc":null}
+{"kind":"CompileSuccess","fnLoc":{"start":{"line":4,"column":15,"index":122},"end":{"line":13,"column":1,"index":372},"filename":"derived-state-from-default-props.ts"},"fnName":"Component","memoSlots":5,"memoBlocks":2,"memoValues":3,"prunedMemoBlocks":0,"prunedMemoValues":0}
 ```
       
 ### Eval output

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/effect-derived-computations/derived-state-from-default-props.js

@@ -1,4 +1,4 @@
-// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly @outputMode:"lint"
+// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly
 import {useEffect, useState} from 'react';
 
 export default function Component({input = 'empty'}) {

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/effect-derived-computations/derived-state-from-local-state-in-effect.expect.md

@@ -2,7 +2,7 @@
 ## Input
 
 ```javascript
-// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly @outputMode:"lint"
+// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly
 
 import {useEffect, useState} from 'react';
 
@@ -23,20 +23,45 @@ function Component({shouldChange}) {
 ## Code
 
 ```javascript
-// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly @outputMode:"lint"
+import { c as _c } from "react/compiler-runtime"; // @validateNoDerivedComputationsInEffects_exp @loggerTestOnly
 
 import { useEffect, useState } from "react";
 
-function Component({ shouldChange }) {
+function Component(t0) {
+  const $ = _c(7);
+  const { shouldChange } = t0;
   const [count, setCount] = useState(0);
-
-  useEffect(() => {
-    if (shouldChange) {
-      setCount(count + 1);
-    }
-  }, [count]);
-
-  return <div>{count}</div>;
+  let t1;
+  if ($[0] !== count || $[1] !== shouldChange) {
+    t1 = () => {
+      if (shouldChange) {
+        setCount(count + 1);
+      }
+    };
+    $[0] = count;
+    $[1] = shouldChange;
+    $[2] = t1;
+  } else {
+    t1 = $[2];
+  }
+  let t2;
+  if ($[3] !== count) {
+    t2 = [count];
+    $[3] = count;
+    $[4] = t2;
+  } else {
+    t2 = $[4];
+  }
+  useEffect(t1, t2);
+  let t3;
+  if ($[5] !== count) {
+    t3 = <div>{count}</div>;
+    $[5] = count;
+    $[6] = t3;
+  } else {
+    t3 = $[6];
+  }
+  return t3;
 }
 
 ```
@@ -44,8 +69,8 @@ function Component({ shouldChange }) {
 ## Logs
 
 ```
-{"kind":"CompileError","detail":{"options":{"description":"Using an effect triggers an additional render which can hurt performance and user experience, potentially briefly showing stale values to the user\n\nThis setState call is setting a derived value that depends on the following reactive sources:\n\nState: [count]\n\nData Flow Tree:\n└── count (State)\n\nSee: https://react.dev/learn/you-might-not-need-an-effect#updating-state-based-on-props-or-state","category":"EffectDerivationsOfState","reason":"You might not need an effect. Derive values in render, not effects.","details":[{"kind":"error","loc":{"start":{"line":10,"column":6,"index":256},"end":{"line":10,"column":14,"index":264},"filename":"derived-state-from-local-state-in-effect.ts","identifierName":"setCount"},"message":"This should be computed during render, not in an effect"}]}},"fnLoc":null}
-{"kind":"CompileSuccess","fnLoc":{"start":{"line":5,"column":0,"index":127},"end":{"line":15,"column":1,"index":329},"filename":"derived-state-from-local-state-in-effect.ts"},"fnName":"Component","memoSlots":7,"memoBlocks":3,"memoValues":3,"prunedMemoBlocks":0,"prunedMemoValues":0}
+{"kind":"CompileError","detail":{"options":{"description":"Using an effect triggers an additional render which can hurt performance and user experience, potentially briefly showing stale values to the user\n\nThis setState call is setting a derived value that depends on the following reactive sources:\n\nState: [count]\n\nData Flow Tree:\n└── count (State)\n\nSee: https://react.dev/learn/you-might-not-need-an-effect#updating-state-based-on-props-or-state","category":"EffectDerivationsOfState","reason":"You might not need an effect. Derive values in render, not effects.","details":[{"kind":"error","loc":{"start":{"line":10,"column":6,"index":237},"end":{"line":10,"column":14,"index":245},"filename":"derived-state-from-local-state-in-effect.ts","identifierName":"setCount"},"message":"This should be computed during render, not in an effect"}]}},"fnLoc":null}
+{"kind":"CompileSuccess","fnLoc":{"start":{"line":5,"column":0,"index":108},"end":{"line":15,"column":1,"index":310},"filename":"derived-state-from-local-state-in-effect.ts"},"fnName":"Component","memoSlots":7,"memoBlocks":3,"memoValues":3,"prunedMemoBlocks":0,"prunedMemoValues":0}
 ```
       
 ### Eval output

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/effect-derived-computations/derived-state-from-local-state-in-effect.js

@@ -1,4 +1,4 @@
-// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly @outputMode:"lint"
+// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly
 
 import {useEffect, useState} from 'react';
 

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/effect-derived-computations/derived-state-from-prop-local-state-and-component-scope.expect.md

@@ -2,7 +2,7 @@
 ## Input
 
 ```javascript
-// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly @outputMode:"lint"
+// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly
 import {useEffect, useState} from 'react';
 
 function Component({firstName}) {
@@ -33,25 +33,68 @@ export const FIXTURE_ENTRYPOINT = {
 ## Code
 
 ```javascript
-// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly @outputMode:"lint"
+import { c as _c } from "react/compiler-runtime"; // @validateNoDerivedComputationsInEffects_exp @loggerTestOnly
 import { useEffect, useState } from "react";
 
-function Component({ firstName }) {
+function Component(t0) {
+  const $ = _c(12);
+  const { firstName } = t0;
   const [lastName, setLastName] = useState("Doe");
   const [fullName, setFullName] = useState("John");
-
-  const middleName = "D.";
-
-  useEffect(() => {
-    setFullName(firstName + " " + middleName + " " + lastName);
-  }, [firstName, middleName, lastName]);
-
-  return (
-    <div>
-      <input value={lastName} onChange={(e) => setLastName(e.target.value)} />
-      <div>{fullName}</div>
-    </div>
-  );
+  let t1;
+  let t2;
+  if ($[0] !== firstName || $[1] !== lastName) {
+    t1 = () => {
+      setFullName(firstName + " " + "D." + " " + lastName);
+    };
+    t2 = [firstName, "D.", lastName];
+    $[0] = firstName;
+    $[1] = lastName;
+    $[2] = t1;
+    $[3] = t2;
+  } else {
+    t1 = $[2];
+    t2 = $[3];
+  }
+  useEffect(t1, t2);
+  let t3;
+  if ($[4] === Symbol.for("react.memo_cache_sentinel")) {
+    t3 = (e) => setLastName(e.target.value);
+    $[4] = t3;
+  } else {
+    t3 = $[4];
+  }
+  let t4;
+  if ($[5] !== lastName) {
+    t4 = <input value={lastName} onChange={t3} />;
+    $[5] = lastName;
+    $[6] = t4;
+  } else {
+    t4 = $[6];
+  }
+  let t5;
+  if ($[7] !== fullName) {
+    t5 = <div>{fullName}</div>;
+    $[7] = fullName;
+    $[8] = t5;
+  } else {
+    t5 = $[8];
+  }
+  let t6;
+  if ($[9] !== t4 || $[10] !== t5) {
+    t6 = (
+      <div>
+        {t4}
+        {t5}
+      </div>
+    );
+    $[9] = t4;
+    $[10] = t5;
+    $[11] = t6;
+  } else {
+    t6 = $[11];
+  }
+  return t6;
 }
 
 export const FIXTURE_ENTRYPOINT = {
@@ -64,8 +107,8 @@ export const FIXTURE_ENTRYPOINT = {
 ## Logs
 
 ```
-{"kind":"CompileError","detail":{"options":{"description":"Using an effect triggers an additional render which can hurt performance and user experience, potentially briefly showing stale values to the user\n\nThis setState call is setting a derived value that depends on the following reactive sources:\n\nProps: [firstName]\nState: [lastName]\n\nData Flow Tree:\n├── firstName (Prop)\n└── lastName (State)\n\nSee: https://react.dev/learn/you-might-not-need-an-effect#updating-state-based-on-props-or-state","category":"EffectDerivationsOfState","reason":"You might not need an effect. Derive values in render, not effects.","details":[{"kind":"error","loc":{"start":{"line":11,"column":4,"index":316},"end":{"line":11,"column":15,"index":327},"filename":"derived-state-from-prop-local-state-and-component-scope.ts","identifierName":"setFullName"},"message":"This should be computed during render, not in an effect"}]}},"fnLoc":null}
-{"kind":"CompileSuccess","fnLoc":{"start":{"line":4,"column":0,"index":126},"end":{"line":20,"column":1,"index":561},"filename":"derived-state-from-prop-local-state-and-component-scope.ts"},"fnName":"Component","memoSlots":12,"memoBlocks":5,"memoValues":6,"prunedMemoBlocks":0,"prunedMemoValues":0}
+{"kind":"CompileError","detail":{"options":{"description":"Using an effect triggers an additional render which can hurt performance and user experience, potentially briefly showing stale values to the user\n\nThis setState call is setting a derived value that depends on the following reactive sources:\n\nProps: [firstName]\nState: [lastName]\n\nData Flow Tree:\n├── firstName (Prop)\n└── lastName (State)\n\nSee: https://react.dev/learn/you-might-not-need-an-effect#updating-state-based-on-props-or-state","category":"EffectDerivationsOfState","reason":"You might not need an effect. Derive values in render, not effects.","details":[{"kind":"error","loc":{"start":{"line":11,"column":4,"index":297},"end":{"line":11,"column":15,"index":308},"filename":"derived-state-from-prop-local-state-and-component-scope.ts","identifierName":"setFullName"},"message":"This should be computed during render, not in an effect"}]}},"fnLoc":null}
+{"kind":"CompileSuccess","fnLoc":{"start":{"line":4,"column":0,"index":107},"end":{"line":20,"column":1,"index":542},"filename":"derived-state-from-prop-local-state-and-component-scope.ts"},"fnName":"Component","memoSlots":12,"memoBlocks":5,"memoValues":6,"prunedMemoBlocks":0,"prunedMemoValues":0}
 ```
       
 ### Eval output

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/effect-derived-computations/derived-state-from-prop-local-state-and-component-scope.js

@@ -1,4 +1,4 @@
-// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly @outputMode:"lint"
+// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly
 import {useEffect, useState} from 'react';
 
 function Component({firstName}) {

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/effect-derived-computations/derived-state-from-prop-setter-call-outside-effect-no-error.expect.md

@@ -2,7 +2,7 @@
 ## Input
 
 ```javascript
-// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly @outputMode:"lint"
+// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly
 import {useEffect, useState} from 'react';
 
 function Component({initialName}) {
@@ -29,21 +29,48 @@ export const FIXTURE_ENTRYPOINT = {
 ## Code
 
 ```javascript
-// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly @outputMode:"lint"
+import { c as _c } from "react/compiler-runtime"; // @validateNoDerivedComputationsInEffects_exp @loggerTestOnly
 import { useEffect, useState } from "react";
 
-function Component({ initialName }) {
+function Component(t0) {
+  const $ = _c(6);
+  const { initialName } = t0;
   const [name, setName] = useState("");
-
-  useEffect(() => {
-    setName(initialName);
-  }, [initialName]);
-
-  return (
-    <div>
-      <input value={name} onChange={(e) => setName(e.target.value)} />
-    </div>
-  );
+  let t1;
+  let t2;
+  if ($[0] !== initialName) {
+    t1 = () => {
+      setName(initialName);
+    };
+    t2 = [initialName];
+    $[0] = initialName;
+    $[1] = t1;
+    $[2] = t2;
+  } else {
+    t1 = $[1];
+    t2 = $[2];
+  }
+  useEffect(t1, t2);
+  let t3;
+  if ($[3] === Symbol.for("react.memo_cache_sentinel")) {
+    t3 = (e) => setName(e.target.value);
+    $[3] = t3;
+  } else {
+    t3 = $[3];
+  }
+  let t4;
+  if ($[4] !== name) {
+    t4 = (
+      <div>
+        <input value={name} onChange={t3} />
+      </div>
+    );
+    $[4] = name;
+    $[5] = t4;
+  } else {
+    t4 = $[5];
+  }
+  return t4;
 }
 
 export const FIXTURE_ENTRYPOINT = {
@@ -56,7 +83,7 @@ export const FIXTURE_ENTRYPOINT = {
 ## Logs
 
 ```
-{"kind":"CompileSuccess","fnLoc":{"start":{"line":4,"column":0,"index":126},"end":{"line":16,"column":1,"index":378},"filename":"derived-state-from-prop-setter-call-outside-effect-no-error.ts"},"fnName":"Component","memoSlots":6,"memoBlocks":3,"memoValues":4,"prunedMemoBlocks":0,"prunedMemoValues":0}
+{"kind":"CompileSuccess","fnLoc":{"start":{"line":4,"column":0,"index":107},"end":{"line":16,"column":1,"index":359},"filename":"derived-state-from-prop-setter-call-outside-effect-no-error.ts"},"fnName":"Component","memoSlots":6,"memoBlocks":3,"memoValues":4,"prunedMemoBlocks":0,"prunedMemoValues":0}
 ```
       
 ### Eval output

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/effect-derived-computations/derived-state-from-prop-setter-call-outside-effect-no-error.js

@@ -1,4 +1,4 @@
-// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly @outputMode:"lint"
+// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly
 import {useEffect, useState} from 'react';
 
 function Component({initialName}) {

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/effect-derived-computations/derived-state-from-prop-setter-ternary.expect.md

@@ -2,7 +2,7 @@
 ## Input
 
 ```javascript
-// @validateNoDerivedComputationsInEffects_exp @outputMode:"lint"
+// @validateNoDerivedComputationsInEffects_exp
 
 function Component({value}) {
   const [checked, setChecked] = useState('');
@@ -19,16 +19,36 @@ function Component({value}) {
 ## Code
 
 ```javascript
-// @validateNoDerivedComputationsInEffects_exp @outputMode:"lint"
+import { c as _c } from "react/compiler-runtime"; // @validateNoDerivedComputationsInEffects_exp
 
-function Component({ value }) {
+function Component(t0) {
+  const $ = _c(5);
+  const { value } = t0;
   const [checked, setChecked] = useState("");
-
-  useEffect(() => {
-    setChecked(value === "" ? [] : value.split(","));
-  }, [value]);
-
-  return <div>{checked}</div>;
+  let t1;
+  let t2;
+  if ($[0] !== value) {
+    t1 = () => {
+      setChecked(value === "" ? [] : value.split(","));
+    };
+    t2 = [value];
+    $[0] = value;
+    $[1] = t1;
+    $[2] = t2;
+  } else {
+    t1 = $[1];
+    t2 = $[2];
+  }
+  useEffect(t1, t2);
+  let t3;
+  if ($[3] !== checked) {
+    t3 = <div>{checked}</div>;
+    $[3] = checked;
+    $[4] = t3;
+  } else {
+    t3 = $[4];
+  }
+  return t3;
 }
 
 ```

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/effect-derived-computations/derived-state-from-prop-setter-ternary.js

@@ -1,4 +1,4 @@
-// @validateNoDerivedComputationsInEffects_exp @outputMode:"lint"
+// @validateNoDerivedComputationsInEffects_exp
 
 function Component({value}) {
   const [checked, setChecked] = useState('');

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/effect-derived-computations/derived-state-from-prop-setter-used-outside-effect-no-error.expect.md

@@ -2,7 +2,7 @@
 ## Input
 
 ```javascript
-// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly @outputMode:"lint"
+// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly
 import {useEffect, useState} from 'react';
 
 function MockComponent({onSet}) {
@@ -28,20 +28,50 @@ export const FIXTURE_ENTRYPOINT = {
 ## Code
 
 ```javascript
-// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly @outputMode:"lint"
+import { c as _c } from "react/compiler-runtime"; // @validateNoDerivedComputationsInEffects_exp @loggerTestOnly
 import { useEffect, useState } from "react";
 
-function MockComponent({ onSet }) {
-  return <div onClick={() => onSet("clicked")}>Mock Component</div>;
+function MockComponent(t0) {
+  const $ = _c(2);
+  const { onSet } = t0;
+  let t1;
+  if ($[0] !== onSet) {
+    t1 = <div onClick={() => onSet("clicked")}>Mock Component</div>;
+    $[0] = onSet;
+    $[1] = t1;
+  } else {
+    t1 = $[1];
+  }
+  return t1;
 }
 
-function Component({ propValue }) {
-  const [value, setValue] = useState(null);
-  useEffect(() => {
-    setValue(propValue);
-  }, [propValue]);
-
-  return <MockComponent onSet={setValue} />;
+function Component(t0) {
+  const $ = _c(4);
+  const { propValue } = t0;
+  const [, setValue] = useState(null);
+  let t1;
+  let t2;
+  if ($[0] !== propValue) {
+    t1 = () => {
+      setValue(propValue);
+    };
+    t2 = [propValue];
+    $[0] = propValue;
+    $[1] = t1;
+    $[2] = t2;
+  } else {
+    t1 = $[1];
+    t2 = $[2];
+  }
+  useEffect(t1, t2);
+  let t3;
+  if ($[3] === Symbol.for("react.memo_cache_sentinel")) {
+    t3 = <MockComponent onSet={setValue} />;
+    $[3] = t3;
+  } else {
+    t3 = $[3];
+  }
+  return t3;
 }
 
 export const FIXTURE_ENTRYPOINT = {
@@ -54,8 +84,8 @@ export const FIXTURE_ENTRYPOINT = {
 ## Logs
 
 ```
-{"kind":"CompileSuccess","fnLoc":{"start":{"line":4,"column":0,"index":126},"end":{"line":6,"column":1,"index":230},"filename":"derived-state-from-prop-setter-used-outside-effect-no-error.ts"},"fnName":"MockComponent","memoSlots":2,"memoBlocks":1,"memoValues":1,"prunedMemoBlocks":0,"prunedMemoValues":0}
-{"kind":"CompileSuccess","fnLoc":{"start":{"line":8,"column":0,"index":232},"end":{"line":15,"column":1,"index":421},"filename":"derived-state-from-prop-setter-used-outside-effect-no-error.ts"},"fnName":"Component","memoSlots":4,"memoBlocks":2,"memoValues":3,"prunedMemoBlocks":0,"prunedMemoValues":0}
+{"kind":"CompileSuccess","fnLoc":{"start":{"line":4,"column":0,"index":107},"end":{"line":6,"column":1,"index":211},"filename":"derived-state-from-prop-setter-used-outside-effect-no-error.ts"},"fnName":"MockComponent","memoSlots":2,"memoBlocks":1,"memoValues":1,"prunedMemoBlocks":0,"prunedMemoValues":0}
+{"kind":"CompileSuccess","fnLoc":{"start":{"line":8,"column":0,"index":213},"end":{"line":15,"column":1,"index":402},"filename":"derived-state-from-prop-setter-used-outside-effect-no-error.ts"},"fnName":"Component","memoSlots":4,"memoBlocks":2,"memoValues":3,"prunedMemoBlocks":0,"prunedMemoValues":0}
 ```
       
 ### Eval output

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/effect-derived-computations/derived-state-from-prop-setter-used-outside-effect-no-error.js

@@ -1,4 +1,4 @@
-// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly @outputMode:"lint"
+// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly
 import {useEffect, useState} from 'react';
 
 function MockComponent({onSet}) {

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/effect-derived-computations/derived-state-from-prop-with-side-effect.expect.md

@@ -2,7 +2,7 @@
 ## Input
 
 ```javascript
-// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly @outputMode:"lint"
+// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly
 import {useEffect, useState} from 'react';
 
 function Component({value}) {
@@ -26,18 +26,38 @@ export const FIXTURE_ENTRYPOINT = {
 ## Code
 
 ```javascript
-// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly @outputMode:"lint"
+import { c as _c } from "react/compiler-runtime"; // @validateNoDerivedComputationsInEffects_exp @loggerTestOnly
 import { useEffect, useState } from "react";
 
-function Component({ value }) {
+function Component(t0) {
+  const $ = _c(5);
+  const { value } = t0;
   const [localValue, setLocalValue] = useState("");
-
-  useEffect(() => {
-    setLocalValue(value);
-    document.title = `Value: ${value}`;
-  }, [value]);
-
-  return <div>{localValue}</div>;
+  let t1;
+  let t2;
+  if ($[0] !== value) {
+    t1 = () => {
+      setLocalValue(value);
+      document.title = `Value: ${value}`;
+    };
+    t2 = [value];
+    $[0] = value;
+    $[1] = t1;
+    $[2] = t2;
+  } else {
+    t1 = $[1];
+    t2 = $[2];
+  }
+  useEffect(t1, t2);
+  let t3;
+  if ($[3] !== localValue) {
+    t3 = <div>{localValue}</div>;
+    $[3] = localValue;
+    $[4] = t3;
+  } else {
+    t3 = $[4];
+  }
+  return t3;
 }
 
 export const FIXTURE_ENTRYPOINT = {
@@ -50,8 +70,8 @@ export const FIXTURE_ENTRYPOINT = {
 ## Logs
 
 ```
-{"kind":"CompileError","detail":{"options":{"description":"Using an effect triggers an additional render which can hurt performance and user experience, potentially briefly showing stale values to the user\n\nThis setState call is setting a derived value that depends on the following reactive sources:\n\nProps: [value]\n\nData Flow Tree:\n└── value (Prop)\n\nSee: https://react.dev/learn/you-might-not-need-an-effect#updating-state-based-on-props-or-state","category":"EffectDerivationsOfState","reason":"You might not need an effect. Derive values in render, not effects.","details":[{"kind":"error","loc":{"start":{"line":8,"column":4,"index":233},"end":{"line":8,"column":17,"index":246},"filename":"derived-state-from-prop-with-side-effect.ts","identifierName":"setLocalValue"},"message":"This should be computed during render, not in an effect"}]}},"fnLoc":null}
-{"kind":"CompileSuccess","fnLoc":{"start":{"line":4,"column":0,"index":126},"end":{"line":13,"column":1,"index":346},"filename":"derived-state-from-prop-with-side-effect.ts"},"fnName":"Component","memoSlots":5,"memoBlocks":2,"memoValues":3,"prunedMemoBlocks":0,"prunedMemoValues":0}
+{"kind":"CompileError","detail":{"options":{"description":"Using an effect triggers an additional render which can hurt performance and user experience, potentially briefly showing stale values to the user\n\nThis setState call is setting a derived value that depends on the following reactive sources:\n\nProps: [value]\n\nData Flow Tree:\n└── value (Prop)\n\nSee: https://react.dev/learn/you-might-not-need-an-effect#updating-state-based-on-props-or-state","category":"EffectDerivationsOfState","reason":"You might not need an effect. Derive values in render, not effects.","details":[{"kind":"error","loc":{"start":{"line":8,"column":4,"index":214},"end":{"line":8,"column":17,"index":227},"filename":"derived-state-from-prop-with-side-effect.ts","identifierName":"setLocalValue"},"message":"This should be computed during render, not in an effect"}]}},"fnLoc":null}
+{"kind":"CompileSuccess","fnLoc":{"start":{"line":4,"column":0,"index":107},"end":{"line":13,"column":1,"index":327},"filename":"derived-state-from-prop-with-side-effect.ts"},"fnName":"Component","memoSlots":5,"memoBlocks":2,"memoValues":3,"prunedMemoBlocks":0,"prunedMemoValues":0}
 ```
       
 ### Eval output

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/effect-derived-computations/derived-state-from-prop-with-side-effect.js

@@ -1,4 +1,4 @@
-// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly @outputMode:"lint"
+// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly
 import {useEffect, useState} from 'react';
 
 function Component({value}) {

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/effect-derived-computations/derived-state-from-ref-and-state-no-error.expect.md

@@ -2,7 +2,7 @@
 ## Input
 
 ```javascript
-// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly @outputMode:"lint"
+// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly
 import {useEffect, useState, useRef} from 'react';
 
 export default function Component({test}) {
@@ -27,19 +27,39 @@ export const FIXTURE_ENTRYPOINT = {
 ## Code
 
 ```javascript
-// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly @outputMode:"lint"
+import { c as _c } from "react/compiler-runtime"; // @validateNoDerivedComputationsInEffects_exp @loggerTestOnly
 import { useEffect, useState, useRef } from "react";
 
-export default function Component({ test }) {
+export default function Component(t0) {
+  const $ = _c(5);
+  const { test } = t0;
   const [local, setLocal] = useState("");
 
   const myRef = useRef(null);
-
-  useEffect(() => {
-    setLocal(myRef.current + test);
-  }, [test]);
-
-  return <>{local}</>;
+  let t1;
+  let t2;
+  if ($[0] !== test) {
+    t1 = () => {
+      setLocal(myRef.current + test);
+    };
+    t2 = [test];
+    $[0] = test;
+    $[1] = t1;
+    $[2] = t2;
+  } else {
+    t1 = $[1];
+    t2 = $[2];
+  }
+  useEffect(t1, t2);
+  let t3;
+  if ($[3] !== local) {
+    t3 = <>{local}</>;
+    $[3] = local;
+    $[4] = t3;
+  } else {
+    t3 = $[4];
+  }
+  return t3;
 }
 
 export const FIXTURE_ENTRYPOINT = {
@@ -52,7 +72,7 @@ export const FIXTURE_ENTRYPOINT = {
 ## Logs
 
 ```
-{"kind":"CompileSuccess","fnLoc":{"start":{"line":4,"column":15,"index":149},"end":{"line":14,"column":1,"index":347},"filename":"derived-state-from-ref-and-state-no-error.ts"},"fnName":"Component","memoSlots":5,"memoBlocks":2,"memoValues":3,"prunedMemoBlocks":0,"prunedMemoValues":0}
+{"kind":"CompileSuccess","fnLoc":{"start":{"line":4,"column":15,"index":130},"end":{"line":14,"column":1,"index":328},"filename":"derived-state-from-ref-and-state-no-error.ts"},"fnName":"Component","memoSlots":5,"memoBlocks":2,"memoValues":3,"prunedMemoBlocks":0,"prunedMemoValues":0}
 ```
       
 ### Eval output

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/effect-derived-computations/derived-state-from-ref-and-state-no-error.js

@@ -1,4 +1,4 @@
-// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly @outputMode:"lint"
+// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly
 import {useEffect, useState, useRef} from 'react';
 
 export default function Component({test}) {

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/effect-derived-computations/effect-contains-local-function-call.expect.md

@@ -2,7 +2,7 @@
 ## Input
 
 ```javascript
-// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly @outputMode:"lint"
+// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly
 import {useEffect, useState} from 'react';
 
 function Component({propValue}) {
@@ -30,22 +30,48 @@ export const FIXTURE_ENTRYPOINT = {
 ## Code
 
 ```javascript
-// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly @outputMode:"lint"
+import { c as _c } from "react/compiler-runtime"; // @validateNoDerivedComputationsInEffects_exp @loggerTestOnly
 import { useEffect, useState } from "react";
 
-function Component({ propValue }) {
+function Component(t0) {
+  const $ = _c(6);
+  const { propValue } = t0;
   const [value, setValue] = useState(null);
-
-  function localFunction() {
-    console.log("local function");
+  let t1;
+  if ($[0] === Symbol.for("react.memo_cache_sentinel")) {
+    t1 = function localFunction() {
+      console.log("local function");
+    };
+    $[0] = t1;
+  } else {
+    t1 = $[0];
   }
-
-  useEffect(() => {
-    setValue(propValue);
-    localFunction();
-  }, [propValue]);
-
-  return <div>{value}</div>;
+  const localFunction = t1;
+  let t2;
+  let t3;
+  if ($[1] !== propValue) {
+    t2 = () => {
+      setValue(propValue);
+      localFunction();
+    };
+    t3 = [propValue];
+    $[1] = propValue;
+    $[2] = t2;
+    $[3] = t3;
+  } else {
+    t2 = $[2];
+    t3 = $[3];
+  }
+  useEffect(t2, t3);
+  let t4;
+  if ($[4] !== value) {
+    t4 = <div>{value}</div>;
+    $[4] = value;
+    $[5] = t4;
+  } else {
+    t4 = $[5];
+  }
+  return t4;
 }
 
 export const FIXTURE_ENTRYPOINT = {
@@ -58,8 +84,8 @@ export const FIXTURE_ENTRYPOINT = {
 ## Logs
 
 ```
-{"kind":"CompileError","detail":{"options":{"description":"Using an effect triggers an additional render which can hurt performance and user experience, potentially briefly showing stale values to the user\n\nThis setState call is setting a derived value that depends on the following reactive sources:\n\nProps: [propValue]\n\nData Flow Tree:\n└── propValue (Prop)\n\nSee: https://react.dev/learn/you-might-not-need-an-effect#updating-state-based-on-props-or-state","category":"EffectDerivationsOfState","reason":"You might not need an effect. Derive values in render, not effects.","details":[{"kind":"error","loc":{"start":{"line":12,"column":4,"index":298},"end":{"line":12,"column":12,"index":306},"filename":"effect-contains-local-function-call.ts","identifierName":"setValue"},"message":"This should be computed during render, not in an effect"}]}},"fnLoc":null}
-{"kind":"CompileSuccess","fnLoc":{"start":{"line":4,"column":0,"index":126},"end":{"line":17,"column":1,"index":390},"filename":"effect-contains-local-function-call.ts"},"fnName":"Component","memoSlots":6,"memoBlocks":3,"memoValues":4,"prunedMemoBlocks":0,"prunedMemoValues":0}
+{"kind":"CompileError","detail":{"options":{"description":"Using an effect triggers an additional render which can hurt performance and user experience, potentially briefly showing stale values to the user\n\nThis setState call is setting a derived value that depends on the following reactive sources:\n\nProps: [propValue]\n\nData Flow Tree:\n└── propValue (Prop)\n\nSee: https://react.dev/learn/you-might-not-need-an-effect#updating-state-based-on-props-or-state","category":"EffectDerivationsOfState","reason":"You might not need an effect. Derive values in render, not effects.","details":[{"kind":"error","loc":{"start":{"line":12,"column":4,"index":279},"end":{"line":12,"column":12,"index":287},"filename":"effect-contains-local-function-call.ts","identifierName":"setValue"},"message":"This should be computed during render, not in an effect"}]}},"fnLoc":null}
+{"kind":"CompileSuccess","fnLoc":{"start":{"line":4,"column":0,"index":107},"end":{"line":17,"column":1,"index":371},"filename":"effect-contains-local-function-call.ts"},"fnName":"Component","memoSlots":6,"memoBlocks":3,"memoValues":4,"prunedMemoBlocks":0,"prunedMemoValues":0}
 ```
       
 ### Eval output

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/effect-derived-computations/effect-contains-local-function-call.js

@@ -1,4 +1,4 @@
-// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly @outputMode:"lint"
+// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly
 import {useEffect, useState} from 'react';
 
 function Component({propValue}) {

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/effect-derived-computations/effect-contains-prop-function-call-no-error.expect.md

@@ -2,7 +2,7 @@
 ## Input
 
 ```javascript
-// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly @outputMode:"lint"
+// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly
 import {useEffect, useState} from 'react';
 
 function Component({propValue, onChange}) {
@@ -25,17 +25,43 @@ export const FIXTURE_ENTRYPOINT = {
 ## Code
 
 ```javascript
-// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly @outputMode:"lint"
+import { c as _c } from "react/compiler-runtime"; // @validateNoDerivedComputationsInEffects_exp @loggerTestOnly
 import { useEffect, useState } from "react";
 
-function Component({ propValue, onChange }) {
+function Component(t0) {
+  const $ = _c(7);
+  const { propValue, onChange } = t0;
   const [value, setValue] = useState(null);
-  useEffect(() => {
-    setValue(propValue);
-    onChange();
-  }, [propValue]);
-
-  return <div>{value}</div>;
+  let t1;
+  if ($[0] !== onChange || $[1] !== propValue) {
+    t1 = () => {
+      setValue(propValue);
+      onChange();
+    };
+    $[0] = onChange;
+    $[1] = propValue;
+    $[2] = t1;
+  } else {
+    t1 = $[2];
+  }
+  let t2;
+  if ($[3] !== propValue) {
+    t2 = [propValue];
+    $[3] = propValue;
+    $[4] = t2;
+  } else {
+    t2 = $[4];
+  }
+  useEffect(t1, t2);
+  let t3;
+  if ($[5] !== value) {
+    t3 = <div>{value}</div>;
+    $[5] = value;
+    $[6] = t3;
+  } else {
+    t3 = $[6];
+  }
+  return t3;
 }
 
 export const FIXTURE_ENTRYPOINT = {
@@ -48,8 +74,8 @@ export const FIXTURE_ENTRYPOINT = {
 ## Logs
 
 ```
-{"kind":"CompileSuccess","fnLoc":{"start":{"line":4,"column":0,"index":126},"end":{"line":12,"column":1,"index":325},"filename":"effect-contains-prop-function-call-no-error.ts"},"fnName":"Component","memoSlots":7,"memoBlocks":3,"memoValues":3,"prunedMemoBlocks":0,"prunedMemoValues":0}
-{"kind":"CompileSuccess","fnLoc":{"start":{"line":16,"column":41,"index":421},"end":{"line":16,"column":49,"index":429},"filename":"effect-contains-prop-function-call-no-error.ts"},"fnName":null,"memoSlots":0,"memoBlocks":0,"memoValues":0,"prunedMemoBlocks":0,"prunedMemoValues":0}
+{"kind":"CompileSuccess","fnLoc":{"start":{"line":4,"column":0,"index":107},"end":{"line":12,"column":1,"index":306},"filename":"effect-contains-prop-function-call-no-error.ts"},"fnName":"Component","memoSlots":7,"memoBlocks":3,"memoValues":3,"prunedMemoBlocks":0,"prunedMemoValues":0}
+{"kind":"CompileSuccess","fnLoc":{"start":{"line":16,"column":41,"index":402},"end":{"line":16,"column":49,"index":410},"filename":"effect-contains-prop-function-call-no-error.ts"},"fnName":null,"memoSlots":0,"memoBlocks":0,"memoValues":0,"prunedMemoBlocks":0,"prunedMemoValues":0}
 ```
       
 ### Eval output

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/effect-derived-computations/effect-contains-prop-function-call-no-error.js

@@ -1,4 +1,4 @@
-// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly @outputMode:"lint"
+// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly
 import {useEffect, useState} from 'react';
 
 function Component({propValue, onChange}) {

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/effect-derived-computations/effect-used-in-dep-array-still-errors.expect.md

@@ -2,7 +2,7 @@
 ## Input
 
 ```javascript
-// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly @outputMode:"lint"
+// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly
 
 function Component({prop}) {
   const [s, setS] = useState(0);
@@ -18,15 +18,36 @@ function Component({prop}) {
 ## Code
 
 ```javascript
-// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly @outputMode:"lint"
+import { c as _c } from "react/compiler-runtime"; // @validateNoDerivedComputationsInEffects_exp @loggerTestOnly
 
-function Component({ prop }) {
-  const [s, setS] = useState(0);
-  useEffect(() => {
-    setS(prop);
-  }, [prop, setS]);
-
-  return <div>{prop}</div>;
+function Component(t0) {
+  const $ = _c(5);
+  const { prop } = t0;
+  const [, setS] = useState(0);
+  let t1;
+  let t2;
+  if ($[0] !== prop) {
+    t1 = () => {
+      setS(prop);
+    };
+    t2 = [prop, setS];
+    $[0] = prop;
+    $[1] = t1;
+    $[2] = t2;
+  } else {
+    t1 = $[1];
+    t2 = $[2];
+  }
+  useEffect(t1, t2);
+  let t3;
+  if ($[3] !== prop) {
+    t3 = <div>{prop}</div>;
+    $[3] = prop;
+    $[4] = t3;
+  } else {
+    t3 = $[4];
+  }
+  return t3;
 }
 
 ```
@@ -34,8 +55,8 @@ function Component({ prop }) {
 ## Logs
 
 ```
-{"kind":"CompileError","detail":{"options":{"description":"Using an effect triggers an additional render which can hurt performance and user experience, potentially briefly showing stale values to the user\n\nThis setState call is setting a derived value that depends on the following reactive sources:\n\nProps: [prop]\n\nData Flow Tree:\n└── prop (Prop)\n\nSee: https://react.dev/learn/you-might-not-need-an-effect#updating-state-based-on-props-or-state","category":"EffectDerivationsOfState","reason":"You might not need an effect. Derive values in render, not effects.","details":[{"kind":"error","loc":{"start":{"line":6,"column":4,"index":169},"end":{"line":6,"column":8,"index":173},"filename":"effect-used-in-dep-array-still-errors.ts","identifierName":"setS"},"message":"This should be computed during render, not in an effect"}]}},"fnLoc":null}
-{"kind":"CompileSuccess","fnLoc":{"start":{"line":3,"column":0,"index":83},"end":{"line":10,"column":1,"index":231},"filename":"effect-used-in-dep-array-still-errors.ts"},"fnName":"Component","memoSlots":5,"memoBlocks":2,"memoValues":3,"prunedMemoBlocks":0,"prunedMemoValues":0}
+{"kind":"CompileError","detail":{"options":{"description":"Using an effect triggers an additional render which can hurt performance and user experience, potentially briefly showing stale values to the user\n\nThis setState call is setting a derived value that depends on the following reactive sources:\n\nProps: [prop]\n\nData Flow Tree:\n└── prop (Prop)\n\nSee: https://react.dev/learn/you-might-not-need-an-effect#updating-state-based-on-props-or-state","category":"EffectDerivationsOfState","reason":"You might not need an effect. Derive values in render, not effects.","details":[{"kind":"error","loc":{"start":{"line":6,"column":4,"index":150},"end":{"line":6,"column":8,"index":154},"filename":"effect-used-in-dep-array-still-errors.ts","identifierName":"setS"},"message":"This should be computed during render, not in an effect"}]}},"fnLoc":null}
+{"kind":"CompileSuccess","fnLoc":{"start":{"line":3,"column":0,"index":64},"end":{"line":10,"column":1,"index":212},"filename":"effect-used-in-dep-array-still-errors.ts"},"fnName":"Component","memoSlots":5,"memoBlocks":2,"memoValues":3,"prunedMemoBlocks":0,"prunedMemoValues":0}
 ```
       
 ### Eval output

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/effect-derived-computations/effect-used-in-dep-array-still-errors.js

@@ -1,4 +1,4 @@
-// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly @outputMode:"lint"
+// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly
 
 function Component({prop}) {
   const [s, setS] = useState(0);

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/effect-derived-computations/effect-with-cleanup-function-depending-on-derived-computation-value.expect.md

@@ -2,7 +2,7 @@
 ## Input
 
 ```javascript
-// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly @outputMode:"lint"
+// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly
 
 import {useEffect, useState} from 'react';
 
@@ -29,26 +29,39 @@ function Component(file: File) {
 ## Code
 
 ```javascript
-// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly @outputMode:"lint"
+import { c as _c } from "react/compiler-runtime"; // @validateNoDerivedComputationsInEffects_exp @loggerTestOnly
 
 import { useEffect, useState } from "react";
 
-function Component(file: File) {
+function Component(file) {
+  const $ = _c(5);
   const [imageUrl, setImageUrl] = useState(null);
-
-  /*
-   * Cleaning up the variable or a source of the variable used to setState
-   * inside the effect communicates that we always need to clean up something
-   * which is a valid use case for useEffect. In which case we want to
-   * avoid an throwing
-   */
-  useEffect(() => {
-    const imageUrlPrepared = URL.createObjectURL(file);
-    setImageUrl(imageUrlPrepared);
-    return () => URL.revokeObjectURL(imageUrlPrepared);
-  }, [file]);
-
-  return <Image src={imageUrl} xstyle={styles.imageSizeLimits} />;
+  let t0;
+  let t1;
+  if ($[0] !== file) {
+    t0 = () => {
+      const imageUrlPrepared = URL.createObjectURL(file);
+      setImageUrl(imageUrlPrepared);
+      return () => URL.revokeObjectURL(imageUrlPrepared);
+    };
+    t1 = [file];
+    $[0] = file;
+    $[1] = t0;
+    $[2] = t1;
+  } else {
+    t0 = $[1];
+    t1 = $[2];
+  }
+  useEffect(t0, t1);
+  let t2;
+  if ($[3] !== imageUrl) {
+    t2 = <Image src={imageUrl} xstyle={styles.imageSizeLimits} />;
+    $[3] = imageUrl;
+    $[4] = t2;
+  } else {
+    t2 = $[4];
+  }
+  return t2;
 }
 
 ```
@@ -56,7 +69,7 @@ function Component(file: File) {
 ## Logs
 
 ```
-{"kind":"CompileSuccess","fnLoc":{"start":{"line":5,"column":0,"index":127},"end":{"line":21,"column":1,"index":719},"filename":"effect-with-cleanup-function-depending-on-derived-computation-value.ts"},"fnName":"Component","memoSlots":5,"memoBlocks":2,"memoValues":3,"prunedMemoBlocks":0,"prunedMemoValues":0}
+{"kind":"CompileSuccess","fnLoc":{"start":{"line":5,"column":0,"index":108},"end":{"line":21,"column":1,"index":700},"filename":"effect-with-cleanup-function-depending-on-derived-computation-value.ts"},"fnName":"Component","memoSlots":5,"memoBlocks":2,"memoValues":3,"prunedMemoBlocks":0,"prunedMemoValues":0}
 ```
       
 ### Eval output

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/effect-derived-computations/effect-with-cleanup-function-depending-on-derived-computation-value.js

@@ -1,4 +1,4 @@
-// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly @outputMode:"lint"
+// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly
 
 import {useEffect, useState} from 'react';
 

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/effect-derived-computations/effect-with-global-function-call-no-error.expect.md

@@ -2,7 +2,7 @@
 ## Input
 
 ```javascript
-// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly @outputMode:"lint"
+// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly
 import {useEffect, useState} from 'react';
 
 function Component({propValue}) {
@@ -25,17 +25,38 @@ export const FIXTURE_ENTRYPOINT = {
 ## Code
 
 ```javascript
-// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly @outputMode:"lint"
+import { c as _c } from "react/compiler-runtime"; // @validateNoDerivedComputationsInEffects_exp @loggerTestOnly
 import { useEffect, useState } from "react";
 
-function Component({ propValue }) {
+function Component(t0) {
+  const $ = _c(5);
+  const { propValue } = t0;
   const [value, setValue] = useState(null);
-  useEffect(() => {
-    setValue(propValue);
-    globalCall();
-  }, [propValue]);
-
-  return <div>{value}</div>;
+  let t1;
+  let t2;
+  if ($[0] !== propValue) {
+    t1 = () => {
+      setValue(propValue);
+      globalCall();
+    };
+    t2 = [propValue];
+    $[0] = propValue;
+    $[1] = t1;
+    $[2] = t2;
+  } else {
+    t1 = $[1];
+    t2 = $[2];
+  }
+  useEffect(t1, t2);
+  let t3;
+  if ($[3] !== value) {
+    t3 = <div>{value}</div>;
+    $[3] = value;
+    $[4] = t3;
+  } else {
+    t3 = $[4];
+  }
+  return t3;
 }
 
 export const FIXTURE_ENTRYPOINT = {
@@ -48,7 +69,7 @@ export const FIXTURE_ENTRYPOINT = {
 ## Logs
 
 ```
-{"kind":"CompileSuccess","fnLoc":{"start":{"line":4,"column":0,"index":126},"end":{"line":12,"column":1,"index":317},"filename":"effect-with-global-function-call-no-error.ts"},"fnName":"Component","memoSlots":5,"memoBlocks":2,"memoValues":3,"prunedMemoBlocks":0,"prunedMemoValues":0}
+{"kind":"CompileSuccess","fnLoc":{"start":{"line":4,"column":0,"index":107},"end":{"line":12,"column":1,"index":298},"filename":"effect-with-global-function-call-no-error.ts"},"fnName":"Component","memoSlots":5,"memoBlocks":2,"memoValues":3,"prunedMemoBlocks":0,"prunedMemoValues":0}
 ```
       
 ### Eval output

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/effect-derived-computations/effect-with-global-function-call-no-error.js

@@ -1,4 +1,4 @@
-// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly @outputMode:"lint"
+// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly
 import {useEffect, useState} from 'react';
 
 function Component({propValue}) {

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/effect-derived-computations/from-props-setstate-in-effect-no-error.expect.md

@@ -2,7 +2,7 @@
 ## Input
 
 ```javascript
-// @validateNoDerivedComputationsInEffects_exp @enableTreatSetIdentifiersAsStateSetters @loggerTestOnly @outputMode:"lint"
+// @validateNoDerivedComputationsInEffects_exp @enableTreatSetIdentifiersAsStateSetters @loggerTestOnly
 
 function Component({setParentState, prop}) {
   useEffect(() => {
@@ -17,14 +17,40 @@ function Component({setParentState, prop}) {
 ## Code
 
 ```javascript
-// @validateNoDerivedComputationsInEffects_exp @enableTreatSetIdentifiersAsStateSetters @loggerTestOnly @outputMode:"lint"
+import { c as _c } from "react/compiler-runtime"; // @validateNoDerivedComputationsInEffects_exp @enableTreatSetIdentifiersAsStateSetters @loggerTestOnly
 
-function Component({ setParentState, prop }) {
-  useEffect(() => {
-    setParentState(prop);
-  }, [prop]);
-
-  return <div>{prop}</div>;
+function Component(t0) {
+  const $ = _c(7);
+  const { setParentState, prop } = t0;
+  let t1;
+  if ($[0] !== prop || $[1] !== setParentState) {
+    t1 = () => {
+      setParentState(prop);
+    };
+    $[0] = prop;
+    $[1] = setParentState;
+    $[2] = t1;
+  } else {
+    t1 = $[2];
+  }
+  let t2;
+  if ($[3] !== prop) {
+    t2 = [prop];
+    $[3] = prop;
+    $[4] = t2;
+  } else {
+    t2 = $[4];
+  }
+  useEffect(t1, t2);
+  let t3;
+  if ($[5] !== prop) {
+    t3 = <div>{prop}</div>;
+    $[5] = prop;
+    $[6] = t3;
+  } else {
+    t3 = $[6];
+  }
+  return t3;
 }
 
 ```
@@ -32,7 +58,7 @@ function Component({ setParentState, prop }) {
 ## Logs
 
 ```
-{"kind":"CompileSuccess","fnLoc":{"start":{"line":3,"column":0,"index":124},"end":{"line":9,"column":1,"index":259},"filename":"from-props-setstate-in-effect-no-error.ts"},"fnName":"Component","memoSlots":7,"memoBlocks":3,"memoValues":3,"prunedMemoBlocks":0,"prunedMemoValues":0}
+{"kind":"CompileSuccess","fnLoc":{"start":{"line":3,"column":0,"index":105},"end":{"line":9,"column":1,"index":240},"filename":"from-props-setstate-in-effect-no-error.ts"},"fnName":"Component","memoSlots":7,"memoBlocks":3,"memoValues":3,"prunedMemoBlocks":0,"prunedMemoValues":0}
 ```
       
 ### Eval output

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/effect-derived-computations/from-props-setstate-in-effect-no-error.js

@@ -1,4 +1,4 @@
-// @validateNoDerivedComputationsInEffects_exp @enableTreatSetIdentifiersAsStateSetters @loggerTestOnly @outputMode:"lint"
+// @validateNoDerivedComputationsInEffects_exp @enableTreatSetIdentifiersAsStateSetters @loggerTestOnly
 
 function Component({setParentState, prop}) {
   useEffect(() => {

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/effect-derived-computations/function-expression-mutation-edge-case.expect.md

@@ -2,7 +2,7 @@
 ## Input
 
 ```javascript
-// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly @outputMode:"lint"
+// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly
 
 function Component() {
   const [foo, setFoo] = useState({});
@@ -40,37 +40,66 @@ function Component() {
 ## Code
 
 ```javascript
-// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly @outputMode:"lint"
+import { c as _c } from "react/compiler-runtime"; // @validateNoDerivedComputationsInEffects_exp @loggerTestOnly
 
 function Component() {
-  const [foo, setFoo] = useState({});
-  const [bar, setBar] = useState(new Set());
+  const $ = _c(9);
+  let t0;
+  if ($[0] === Symbol.for("react.memo_cache_sentinel")) {
+    t0 = {};
+    $[0] = t0;
+  } else {
+    t0 = $[0];
+  }
+  const [foo, setFoo] = useState(t0);
+  let t1;
+  if ($[1] === Symbol.for("react.memo_cache_sentinel")) {
+    t1 = new Set();
+    $[1] = t1;
+  } else {
+    t1 = $[1];
+  }
+  const [bar] = useState(t1);
+  let t2;
+  let t3;
+  if ($[2] !== bar || $[3] !== foo) {
+    t2 = () => {
+      let isChanged = false;
 
-  /*
-   * isChanged is considered context of the effect's function expression,
-   * if we don't bail out of effect mutation derivation tracking, isChanged
-   * will inherit the sources of the effect's function expression.
-   *
-   * This is innacurate and with the multiple passes ends up causing an infinite loop.
-   */
-  useEffect(() => {
-    let isChanged = false;
+      const newData = foo.map((val) => {
+        bar.someMethod(val);
+        isChanged = true;
+      });
 
-    const newData = foo.map((val) => {
-      bar.someMethod(val);
-      isChanged = true;
-    });
+      if (isChanged) {
+        setFoo(newData);
+      }
+    };
 
-    if (isChanged) {
-      setFoo(newData);
-    }
-  }, [foo, bar]);
-
-  return (
-    <div>
-      {foo}, {bar}
-    </div>
-  );
+    t3 = [foo, bar];
+    $[2] = bar;
+    $[3] = foo;
+    $[4] = t2;
+    $[5] = t3;
+  } else {
+    t2 = $[4];
+    t3 = $[5];
+  }
+  useEffect(t2, t3);
+  let t4;
+  if ($[6] !== bar || $[7] !== foo) {
+    t4 = (
+      <div>
+        {foo}, {bar}
+      </div>
+    );
+    $[6] = bar;
+    $[7] = foo;
+    $[8] = t4;
+  } else {
+    t4 = $[8];
+  }
+  return t4;
 }
 
 ```
@@ -78,8 +107,8 @@ function Component() {
 ## Logs
 
 ```
-{"kind":"CompileError","detail":{"options":{"description":"Using an effect triggers an additional render which can hurt performance and user experience, potentially briefly showing stale values to the user\n\nThis setState call is setting a derived value that depends on the following reactive sources:\n\nState: [foo, bar]\n\nData Flow Tree:\n└── newData\n    ├── foo (State)\n    └── bar (State)\n\nSee: https://react.dev/learn/you-might-not-need-an-effect#updating-state-based-on-props-or-state","category":"EffectDerivationsOfState","reason":"You might not need an effect. Derive values in render, not effects.","details":[{"kind":"error","loc":{"start":{"line":23,"column":6,"index":682},"end":{"line":23,"column":12,"index":688},"filename":"function-expression-mutation-edge-case.ts","identifierName":"setFoo"},"message":"This should be computed during render, not in an effect"}]}},"fnLoc":null}
-{"kind":"CompileSuccess","fnLoc":{"start":{"line":3,"column":0,"index":83},"end":{"line":32,"column":1,"index":781},"filename":"function-expression-mutation-edge-case.ts"},"fnName":"Component","memoSlots":9,"memoBlocks":4,"memoValues":5,"prunedMemoBlocks":0,"prunedMemoValues":0}
+{"kind":"CompileError","detail":{"options":{"description":"Using an effect triggers an additional render which can hurt performance and user experience, potentially briefly showing stale values to the user\n\nThis setState call is setting a derived value that depends on the following reactive sources:\n\nState: [foo, bar]\n\nData Flow Tree:\n└── newData\n    ├── foo (State)\n    └── bar (State)\n\nSee: https://react.dev/learn/you-might-not-need-an-effect#updating-state-based-on-props-or-state","category":"EffectDerivationsOfState","reason":"You might not need an effect. Derive values in render, not effects.","details":[{"kind":"error","loc":{"start":{"line":23,"column":6,"index":663},"end":{"line":23,"column":12,"index":669},"filename":"function-expression-mutation-edge-case.ts","identifierName":"setFoo"},"message":"This should be computed during render, not in an effect"}]}},"fnLoc":null}
+{"kind":"CompileSuccess","fnLoc":{"start":{"line":3,"column":0,"index":64},"end":{"line":32,"column":1,"index":762},"filename":"function-expression-mutation-edge-case.ts"},"fnName":"Component","memoSlots":9,"memoBlocks":4,"memoValues":5,"prunedMemoBlocks":0,"prunedMemoValues":0}
 ```
       
 ### Eval output

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/effect-derived-computations/function-expression-mutation-edge-case.js

@@ -1,4 +1,4 @@
-// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly @outputMode:"lint"
+// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly
 
 function Component() {
   const [foo, setFoo] = useState({});

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/effect-derived-computations/invalid-derived-computation-in-effect.expect.md

@@ -2,7 +2,7 @@
 ## Input
 
 ```javascript
-// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly @outputMode:"lint"
+// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly
 import {useEffect, useState} from 'react';
 
 function Component() {
@@ -28,20 +28,38 @@ export const FIXTURE_ENTRYPOINT = {
 ## Code
 
 ```javascript
-// @validateNoDerivedComputationsInEffects_exp @loggerTestOnly @outputMode:"lint"
+import { c as _c } from "react/compiler-runtime"; // @validateNoDerivedComputationsInEffects_exp @loggerTestOnly
 import { useEffect, useState } from "react";
 
 function Component() {
-  const [firstName, setFirstName] = useState("Taylor");
-  const lastName = "Swift";
+  const $ = _c(5);
+  const [firstName] = useState("Taylor");
 
-  // 🔴 Avoid: redundant state and unnecessary Effect
   const [fullName, setFullName] = useState("");
-  useEffect(() => {
-    setFullName(firstName + " " + lastName);
-  }, [firstName, lastName]);
-
-  return <div>{fullName}</div>;
+  let t0;
+  let t1;
+  if ($[0] !== firstName) {
+    t0 = () => {
+      setFullName(firstName + " " + "Swift");
+    };
+    t1 = [firstName, "Swift"];
+    $[0] = firstName;
+    $[1] = t0;
+    $[2] = t1;
+  } else {
+    t0 = $[1];
+    t1 = $[2];
+  }
+  useEffect(t0, t1);
+  let t2;
+  if ($[3] !== fullName) {
+    t2 = <div>{fullName}</div>;
+    $[3] = fullName;
+    $[4] = t2;
+  } else {
+    t2 = $[4];
+  }
+  return t2;
 }
 
 export const FIXTURE_ENTRYPOINT = {
@@ -54,8 +72,8 @@ export const FIXTURE_ENTRYPOINT = {
 ## Logs
 
 ```
-{"kind":"CompileError","detail":{"options":{"description":"Using an effect triggers an additional render which can hurt performance and user experience, potentially briefly showing stale values to the user\n\nThis setState call is setting a derived value that depends on the following reactive sources:\n\nState: [firstName]\n\nData Flow Tree:\n└── firstName (State)\n\nSee: https://react.dev/learn/you-might-not-need-an-effect#updating-state-based-on-props-or-state","category":"EffectDerivationsOfState","reason":"You might not need an effect. Derive values in render, not effects.","details":[{"kind":"error","loc":{"start":{"line":11,"column":4,"index":360},"end":{"line":11,"column":15,"index":371},"filename":"invalid-derived-computation-in-effect.ts","identifierName":"setFullName"},"message":"This should be computed during render, not in an effect"}]}},"fnLoc":null}
-{"kind":"CompileSuccess","fnLoc":{"start":{"line":4,"column":0,"index":126},"end":{"line":15,"column":1,"index":464},"filename":"invalid-derived-computation-in-effect.ts"},"fnName":"Component","memoSlots":5,"memoBlocks":2,"memoValues":3,"prunedMemoBlocks":0,"prunedMemoValues":0}
+{"kind":"CompileError","detail":{"options":{"description":"Using an effect triggers an additional render which can hurt performance and user experience, potentially briefly showing stale values to the user\n\nThis setState call is setting a derived value that depends on the following reactive sources:\n\nState: [firstName]\n\nData Flow Tree:\n└── firstName (State)\n\nSee: https://react.dev/learn/you-might-not-need-an-effect#updating-state-based-on-props-or-state","category":"EffectDerivationsOfState","reason":"You might not need an effect. Derive values in render, not effects.","details":[{"kind":"error","loc":{"start":{"line":11,"column":4,"index":341},"end":{"line":11,"column":15,"index":352},"filename":"invalid-derived-computation-in-effect.ts","identifierName":"setFullName"},"message":"This should be computed during render, not in an effect"}]}},"fnLoc":null}
+{"kind":"CompileSuccess","fnLoc":{"start":{"line":4,"column":0,"index":107},"end":{"line":15,"column":1,"index":445},"filename":"invalid-derived-computation-in-effect.ts"},"fnName":"Component","memoSlots":5,"memoBlocks":2,"memoValues":3,"prunedMemoBlocks":0,"prunedMemoValues":0}
 ```
       
 ### Eval output