[compiler] enablePreserveMemo treats manual deps as non-nullable

The `@enablePreserveExistingMemoizationGuarantees` mode can still fail to preserve manual memoization due to mismtached dependencies. Specifically, where the user's dependencies are more precise than the compiler infers bc the compiler is being conservative about what might be nullable. In this mode though we're intentionally using information from the manual memoization and can also rely on the deps as a signal for what's non-nullable.

The idea of the PR is that we treat manual memo deps just like other inferred-as-non-nullable objects during PropagateScopeDeps. We're careful to not treat the full path as non-nullable, only up to the last property index. So `x.y.z` as a manual dep treats `x` and `x.y` as non-nullable, allowing us to preserve a conditional dependency on `x.y.z`.

Optionals within manual dependencies are a bit trickier and aren't handled yet, but hopefully that's less common and something we can improve in a follow-up. Not handling them just means that developers may hit false positives on validating existing memoization if they use optional chains in manual dependencies.

.github/workflows/compiler_prereleases.yml

@@ -19,9 +19,6 @@ on:
       tag_version:
         required: false
         type: string
-      dry_run:
-        required: false
-        type: boolean
     secrets:
       NPM_TOKEN:
         required: true
@@ -58,13 +55,7 @@ jobs:
           key: compiler-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('compiler/yarn.lock') }}
       - run: yarn install --frozen-lockfile
         if: steps.node_modules.outputs.cache-hit != 'true'
-      - if: inputs.dry_run == true
-        name: Publish packages to npm (dry run)
-        run: |
-          cp ./scripts/release/ci-npmrc ~/.npmrc
-          scripts/release/publish.js --frfr --debug --ci --versionName=${{ inputs.version_name }} --tag=${{ inputs.dist_tag }} ${{ inputs.tag_version && format('--tagVersion={0}', inputs.tag_version) || '' }}
-      - if: inputs.dry_run != true
-        name: Publish packages to npm
+      - name: Publish packages to npm
         run: |
           cp ./scripts/release/ci-npmrc ~/.npmrc
           scripts/release/publish.js --frfr --ci --versionName=${{ inputs.version_name }} --tag=${{ inputs.dist_tag }} ${{ inputs.tag_version && format('--tagVersion={0}', inputs.tag_version) || '' }}

.github/workflows/compiler_prereleases_manual.yml

@@ -17,9 +17,6 @@ on:
       tag_version:
         required: false
         type: string
-      dry_run:
-        required: false
-        type: boolean
 
 permissions: {}
 
@@ -36,6 +33,5 @@ jobs:
       dist_tag: ${{ inputs.dist_tag }}
       version_name: ${{ inputs.version_name }}
       tag_version: ${{ inputs.tag_version }}
-      dry_run: ${{ inputs.dry_run }}
     secrets:
       NPM_TOKEN: ${{ secrets.NPM_TOKEN }}

.github/workflows/compiler_prereleases_nightly.yml

@@ -19,6 +19,5 @@ jobs:
       release_channel: experimental
       dist_tag: experimental
       version_name: '0.0.0'
-      dry_run: false
     secrets:
       NPM_TOKEN: ${{ secrets.NPM_TOKEN }}

.github/workflows/runtime_prereleases.yml

@@ -82,6 +82,7 @@ jobs:
         run: |
           scripts/release/publish.js \
             --ci \
+            --skipTests \
             --tags=${{ inputs.dist_tag }} \
             --onlyPackages=${{ inputs.only_packages }} ${{ (inputs.dry && '') || '\'}}
             ${{ inputs.dry && '--dry' || '' }}
@@ -90,10 +91,11 @@ jobs:
         run: |
           scripts/release/publish.js \
             --ci \
+            --skipTests \
             --tags=${{ inputs.dist_tag }} \
             --skipPackages=${{ inputs.skip_packages }} ${{ (inputs.dry && '') || '\'}}
             ${{ inputs.dry && '--dry' || '' }}
-      - if: '${{ !inputs.skip_packages && !inputs.only_packages }}'
+      - if: '${{ !(inputs.skip_packages && inputs.only_packages) }}'
         name: 'Publish all packages'
         run: |
           scripts/release/publish.js \

ReactVersions.js

@@ -33,7 +33,7 @@ const canaryChannelLabel = 'canary';
 const rcNumber = 0;
 
 const stablePackages = {
-  'eslint-plugin-react-hooks': '7.0.0',
+  'eslint-plugin-react-hooks': '6.2.0',
   'jest-react': '0.18.0',
   react: ReactVersion,
   'react-art': ReactVersion,

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

@@ -314,36 +314,6 @@ test('disableMemoizationForDebugging flag works as expected', async ({
   expect(output).toMatchSnapshot('disableMemoizationForDebugging-output.txt');
 });
 
-test('error is displayed when source has syntax error', async ({page}) => {
-  const syntaxErrorSource = `function TestComponent(props) {
-  const oops = props.
-  return (
-    <>{oops}</>
-  );
-}`;
-  const store: Store = {
-    source: syntaxErrorSource,
-    config: defaultConfig,
-    showInternals: false,
-  };
-  const hash = encodeStore(store);
-  await page.goto(`/#${hash}`);
-  await page.waitForFunction(isMonacoLoaded);
-  await expandConfigs(page);
-  await page.screenshot({
-    fullPage: true,
-    path: 'test-results/08-source-syntax-error.png',
-  });
-
-  const text =
-    (await page.locator('.monaco-editor-output').allInnerTexts()) ?? [];
-  const output = text.join('');
-
-  expect(output.replace(/\s+/g, ' ')).toContain(
-    'Expected identifier to be defined before being used',
-  );
-});
-
 TEST_CASE_INPUTS.forEach((t, idx) =>
   test(`playground compiles: ${t.name}`, async ({page}) => {
     const store: Store = {

compiler/apps/playground/components/AccordionWindow.tsx

@@ -7,6 +7,7 @@
 
 import {Resizable} from 're-resizable';
 import React, {
+  useCallback,
   useId,
   unstable_ViewTransition as ViewTransition,
   unstable_addTransitionType as addTransitionType,
@@ -22,6 +23,7 @@ export default function AccordionWindow(props: {
   tabsOpen: Set<string>;
   setTabsOpen: (newTab: Set<string>) => void;
   changedPasses: Set<string>;
+  isFailure: boolean;
 }): React.ReactElement {
   return (
     <div className="flex-1 min-w-[550px] sm:min-w-0">
@@ -35,6 +37,7 @@ export default function AccordionWindow(props: {
               tabsOpen={props.tabsOpen}
               setTabsOpen={props.setTabsOpen}
               hasChanged={props.changedPasses.has(name)}
+              isFailure={props.isFailure}
             />
           );
         })}
@@ -49,6 +52,7 @@ function AccordionWindowItem({
   tabsOpen,
   setTabsOpen,
   hasChanged,
+  isFailure,
 }: {
   name: string;
   tabs: TabsRecord;
@@ -58,11 +62,11 @@ function AccordionWindowItem({
   isFailure: boolean;
 }): React.ReactElement {
   const id = useId();
-  const isShow = tabsOpen.has(name);
+  const isShow = isFailure ? name === 'Output' : tabsOpen.has(name);
 
   const transitionName = `accordion-window-item-${id}`;
 
-  const toggleTabs = (): void => {
+  const toggleTabs = () => {
     startTransition(() => {
       addTransitionType(EXPAND_ACCORDION_TRANSITION);
       const nextState = new Set(tabsOpen);

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

@@ -6,6 +6,7 @@
  */
 
 import MonacoEditor, {loader, type Monaco} from '@monaco-editor/react';
+import {PluginOptions} from 'babel-plugin-react-compiler';
 import type {editor} from 'monaco-editor';
 import * as monaco from 'monaco-editor';
 import React, {
@@ -17,8 +18,9 @@ import React, {
 } from 'react';
 import {Resizable} from 're-resizable';
 import {useStore, useStoreDispatch} from '../StoreContext';
-import {monacoConfigOptions} from './monacoOptions';
+import {monacoOptions} from './monacoOptions';
 import {IconChevron} from '../Icons/IconChevron';
+import prettyFormat from 'pretty-format';
 import {CONFIG_PANEL_TRANSITION} from '../../lib/transitionTypes';
 
 // @ts-expect-error - webpack asset/source loader handles .d.ts files as strings
@@ -27,9 +29,9 @@ import compilerTypeDefs from 'babel-plugin-react-compiler/dist/index.d.ts';
 loader.config({monaco});
 
 export default function ConfigEditor({
-  formattedAppliedConfig,
+  appliedOptions,
 }: {
-  formattedAppliedConfig: string;
+  appliedOptions: PluginOptions | null;
 }): React.ReactElement {
   const [isExpanded, setIsExpanded] = useState(false);
 
@@ -47,7 +49,7 @@ export default function ConfigEditor({
               setIsExpanded(false);
             });
           }}
-          formattedAppliedConfig={formattedAppliedConfig}
+          appliedOptions={appliedOptions}
         />
       </div>
       <div
@@ -69,10 +71,10 @@ export default function ConfigEditor({
 
 function ExpandedEditor({
   onToggle,
-  formattedAppliedConfig,
+  appliedOptions,
 }: {
-  onToggle: (expanded: boolean) => void;
-  formattedAppliedConfig: string;
+  onToggle: () => void;
+  appliedOptions: PluginOptions | null;
 }): React.ReactElement {
   const store = useStore();
   const dispatchStore = useStoreDispatch();
@@ -120,6 +122,13 @@ function ExpandedEditor({
     });
   };
 
+  const formattedAppliedOptions = appliedOptions
+    ? prettyFormat(appliedOptions, {
+        printFunctionName: false,
+        printBasicPrototype: false,
+      })
+    : 'Invalid configs';
+
   return (
     <ViewTransition
       update={{[CONFIG_PANEL_TRANSITION]: 'slide-in', default: 'none'}}>
@@ -149,7 +158,7 @@ function ExpandedEditor({
                 Config Overrides
               </h2>
             </div>
-            <div className="flex-1 border border-gray-300">
+            <div className="flex-1 rounded-lg overflow-hidden border border-gray-300">
               <MonacoEditor
                 path={'config.ts'}
                 language={'typescript'}
@@ -158,7 +167,16 @@ function ExpandedEditor({
                 onChange={handleChange}
                 loading={''}
                 className="monaco-editor-config"
-                options={monacoConfigOptions}
+                options={{
+                  ...monacoOptions,
+                  lineNumbers: 'off',
+                  renderLineHighlight: 'none',
+                  overviewRulerBorder: false,
+                  overviewRulerLanes: 0,
+                  fontSize: 12,
+                  scrollBeyondLastLine: false,
+                  glyphMargin: false,
+                }}
               />
             </div>
           </div>
@@ -168,16 +186,23 @@ function ExpandedEditor({
                 Applied Configs
               </h2>
             </div>
-            <div className="flex-1 border border-gray-300">
+            <div className="flex-1 rounded-lg overflow-hidden border border-gray-300">
               <MonacoEditor
                 path={'applied-config.js'}
                 language={'javascript'}
-                value={formattedAppliedConfig}
+                value={formattedAppliedOptions}
                 loading={''}
                 className="monaco-editor-applied-config"
                 options={{
-                  ...monacoConfigOptions,
+                  ...monacoOptions,
+                  lineNumbers: 'off',
+                  renderLineHighlight: 'none',
+                  overviewRulerBorder: false,
+                  overviewRulerLanes: 0,
+                  fontSize: 12,
+                  scrollBeyondLastLine: false,
                   readOnly: true,
+                  glyphMargin: false,
                 }}
               />
             </div>

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

@@ -5,17 +5,316 @@
  * LICENSE file in the root directory of this source tree.
  */
 
-import {
+import {parse as babelParse, ParseResult} from '@babel/parser';
+import * as HermesParser from 'hermes-parser';
+import * as t from '@babel/types';
+import BabelPluginReactCompiler, {
+  CompilerError,
   CompilerErrorDetail,
   CompilerDiagnostic,
+  Effect,
+  ErrorCategory,
+  parseConfigPragmaForTests,
+  ValueKind,
+  type Hook,
+  PluginOptions,
+  CompilerPipelineValue,
+  parsePluginOptions,
+  printReactiveFunctionWithOutlined,
+  printFunctionWithOutlined,
+  type LoggerEvent,
 } from 'babel-plugin-react-compiler';
-import {useDeferredValue, useMemo, useState} from 'react';
+import {
+  useDeferredValue,
+  useMemo,
+  unstable_ViewTransition as ViewTransition,
+} from 'react';
 import {useStore} from '../StoreContext';
 import ConfigEditor from './ConfigEditor';
 import Input from './Input';
-import {CompilerOutput, default as Output} from './Output';
-import {compile} from '../../lib/compilation';
-import prettyFormat from 'pretty-format';
+import {
+  CompilerOutput,
+  CompilerTransformOutput,
+  default as Output,
+  PrintedCompilerPipelineValue,
+} from './Output';
+import {transformFromAstSync} from '@babel/core';
+
+function parseInput(
+  input: string,
+  language: 'flow' | 'typescript',
+): ParseResult<t.File> {
+  // Extract the first line to quickly check for custom test directives
+  if (language === 'flow') {
+    return HermesParser.parse(input, {
+      babel: true,
+      flow: 'all',
+      sourceType: 'module',
+      enableExperimentalComponentSyntax: true,
+    });
+  } else {
+    return babelParse(input, {
+      plugins: ['typescript', 'jsx'],
+      sourceType: 'module',
+    }) as ParseResult<t.File>;
+  }
+}
+
+function invokeCompiler(
+  source: string,
+  language: 'flow' | 'typescript',
+  options: PluginOptions,
+): CompilerTransformOutput {
+  const ast = parseInput(source, language);
+  let result = transformFromAstSync(ast, source, {
+    filename: '_playgroundFile.js',
+    highlightCode: false,
+    retainLines: true,
+    plugins: [[BabelPluginReactCompiler, options]],
+    ast: true,
+    sourceType: 'module',
+    configFile: false,
+    sourceMaps: true,
+    babelrc: false,
+  });
+  if (result?.ast == null || result?.code == null || result?.map == null) {
+    throw new Error('Expected successful compilation');
+  }
+  return {
+    code: result.code,
+    sourceMaps: result.map,
+    language,
+  };
+}
+
+const COMMON_HOOKS: Array<[string, Hook]> = [
+  [
+    'useFragment',
+    {
+      valueKind: ValueKind.Frozen,
+      effectKind: Effect.Freeze,
+      noAlias: true,
+      transitiveMixedData: true,
+    },
+  ],
+  [
+    'usePaginationFragment',
+    {
+      valueKind: ValueKind.Frozen,
+      effectKind: Effect.Freeze,
+      noAlias: true,
+      transitiveMixedData: true,
+    },
+  ],
+  [
+    'useRefetchableFragment',
+    {
+      valueKind: ValueKind.Frozen,
+      effectKind: Effect.Freeze,
+      noAlias: true,
+      transitiveMixedData: true,
+    },
+  ],
+  [
+    'useLazyLoadQuery',
+    {
+      valueKind: ValueKind.Frozen,
+      effectKind: Effect.Freeze,
+      noAlias: true,
+      transitiveMixedData: true,
+    },
+  ],
+  [
+    'usePreloadedQuery',
+    {
+      valueKind: ValueKind.Frozen,
+      effectKind: Effect.Freeze,
+      noAlias: true,
+      transitiveMixedData: true,
+    },
+  ],
+];
+
+function parseOptions(
+  source: string,
+  mode: 'compiler' | 'linter',
+  configOverrides: string,
+): PluginOptions {
+  // Extract the first line to quickly check for custom test directives
+  const pragma = source.substring(0, source.indexOf('\n'));
+
+  const parsedPragmaOptions = parseConfigPragmaForTests(pragma, {
+    compilationMode: 'infer',
+    environment:
+      mode === 'linter'
+        ? {
+            // enabled in compiler
+            validateRefAccessDuringRender: false,
+            // enabled in linter
+            validateNoSetStateInRender: true,
+            validateNoSetStateInEffects: true,
+            validateNoJSXInTryStatements: true,
+            validateNoImpureFunctionsInRender: true,
+            validateStaticComponents: true,
+            validateNoFreezingKnownMutableFunctions: true,
+            validateNoVoidUseMemo: true,
+          }
+        : {
+            /* use defaults for compiler mode */
+          },
+  });
+
+  // Parse config overrides from config editor
+  let configOverrideOptions: any = {};
+  const configMatch = configOverrides.match(/^\s*import.*?\n\n\((.*)\)/s);
+  if (configOverrides.trim()) {
+    if (configMatch && configMatch[1]) {
+      const configString = configMatch[1].replace(/satisfies.*$/, '').trim();
+      configOverrideOptions = new Function(`return (${configString})`)();
+    } else {
+      throw new Error('Invalid override format');
+    }
+  }
+
+  const opts: PluginOptions = parsePluginOptions({
+    ...parsedPragmaOptions,
+    ...configOverrideOptions,
+    environment: {
+      ...parsedPragmaOptions.environment,
+      ...configOverrideOptions.environment,
+      customHooks: new Map([...COMMON_HOOKS]),
+    },
+  });
+
+  return opts;
+}
+
+function compile(
+  source: string,
+  mode: 'compiler' | 'linter',
+  configOverrides: string,
+): [CompilerOutput, 'flow' | 'typescript', PluginOptions | null] {
+  const results = new Map<string, Array<PrintedCompilerPipelineValue>>();
+  const error = new CompilerError();
+  const otherErrors: Array<CompilerErrorDetail | CompilerDiagnostic> = [];
+  const upsert: (result: PrintedCompilerPipelineValue) => void = result => {
+    const entry = results.get(result.name);
+    if (Array.isArray(entry)) {
+      entry.push(result);
+    } else {
+      results.set(result.name, [result]);
+    }
+  };
+  let language: 'flow' | 'typescript';
+  if (source.match(/\@flow/)) {
+    language = 'flow';
+  } else {
+    language = 'typescript';
+  }
+  let transformOutput;
+
+  let baseOpts: PluginOptions | null = null;
+  try {
+    baseOpts = parseOptions(source, mode, configOverrides);
+  } catch (err) {
+    error.details.push(
+      new CompilerErrorDetail({
+        category: ErrorCategory.Config,
+        reason: `Unexpected failure when transforming configs! \n${err}`,
+        loc: null,
+        suggestions: null,
+      }),
+    );
+  }
+  if (baseOpts) {
+    try {
+      const logIR = (result: CompilerPipelineValue): void => {
+        switch (result.kind) {
+          case 'ast': {
+            break;
+          }
+          case 'hir': {
+            upsert({
+              kind: 'hir',
+              fnName: result.value.id,
+              name: result.name,
+              value: printFunctionWithOutlined(result.value),
+            });
+            break;
+          }
+          case 'reactive': {
+            upsert({
+              kind: 'reactive',
+              fnName: result.value.id,
+              name: result.name,
+              value: printReactiveFunctionWithOutlined(result.value),
+            });
+            break;
+          }
+          case 'debug': {
+            upsert({
+              kind: 'debug',
+              fnName: null,
+              name: result.name,
+              value: result.value,
+            });
+            break;
+          }
+          default: {
+            const _: never = result;
+            throw new Error(`Unhandled result ${result}`);
+          }
+        }
+      };
+      // Add logger options to the parsed options
+      const opts = {
+        ...baseOpts,
+        logger: {
+          debugLogIRs: logIR,
+          logEvent: (_filename: string | null, event: LoggerEvent): void => {
+            if (event.kind === 'CompileError') {
+              otherErrors.push(event.detail);
+            }
+          },
+        },
+      };
+      transformOutput = invokeCompiler(source, language, opts);
+    } catch (err) {
+      /**
+       * error might be an invariant violation or other runtime error
+       * (i.e. object shape that is not CompilerError)
+       */
+      if (err instanceof CompilerError && err.details.length > 0) {
+        error.merge(err);
+      } else {
+        /**
+         * Handle unexpected failures by logging (to get a stack trace)
+         * and reporting
+         */
+        error.details.push(
+          new CompilerErrorDetail({
+            category: ErrorCategory.Invariant,
+            reason: `Unexpected failure when transforming input! \n${err}`,
+            loc: null,
+            suggestions: null,
+          }),
+        );
+      }
+    }
+  }
+  // Only include logger errors if there weren't other errors
+  if (!error.hasErrors() && otherErrors.length !== 0) {
+    otherErrors.forEach(e => error.details.push(e));
+  }
+  if (error.hasErrors()) {
+    return [{kind: 'err', results, error}, language, baseOpts];
+  }
+  return [
+    {kind: 'ok', results, transformOutput, errors: error.details},
+    language,
+    baseOpts,
+  ];
+}
 
 export default function Editor(): JSX.Element {
   const store = useStore();
@@ -28,7 +327,6 @@ export default function Editor(): JSX.Element {
     () => compile(deferredStore.source, 'linter', deferredStore.config),
     [deferredStore.source, deferredStore.config],
   );
-  const [formattedAppliedConfig, setFormattedAppliedConfig] = useState('');
 
   let mergedOutput: CompilerOutput;
   let errors: Array<CompilerErrorDetail | CompilerDiagnostic>;
@@ -42,22 +340,11 @@ export default function Editor(): JSX.Element {
     mergedOutput = compilerOutput;
     errors = compilerOutput.error.details;
   }
-
-  if (appliedOptions) {
-    const formatted = prettyFormat(appliedOptions, {
-      printFunctionName: false,
-      printBasicPrototype: false,
-    });
-    if (formatted !== formattedAppliedConfig) {
-      setFormattedAppliedConfig(formatted);
-    }
-  }
-
   return (
     <>
       <div className="relative flex top-14">
         <div className="flex-shrink-0">
-          <ConfigEditor formattedAppliedConfig={formattedAppliedConfig} />
+          <ConfigEditor appliedOptions={appliedOptions} />
         </div>
         <div className="flex flex-1 min-w-0">
           <Input language={language} errors={errors} />

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

@@ -27,8 +27,6 @@ import {
   useState,
   Suspense,
   unstable_ViewTransition as ViewTransition,
-  unstable_addTransitionType as addTransitionType,
-  startTransition,
 } from 'react';
 import AccordionWindow from '../AccordionWindow';
 import TabbedWindow from '../TabbedWindow';
@@ -37,7 +35,6 @@ import {BabelFileResult} from '@babel/core';
 import {
   CONFIG_PANEL_TRANSITION,
   TOGGLE_INTERNALS_TRANSITION,
-  EXPAND_ACCORDION_TRANSITION,
 } from '../../lib/transitionTypes';
 import {LRUCache} from 'lru-cache';
 
@@ -268,22 +265,8 @@ function OutputContent({store, compilerOutput}: Props): JSX.Element {
    * Update the active tab back to the output or errors tab when the compilation state
    * changes between success/failure.
    */
-  const [previousOutputKind, setPreviousOutputKind] = useState(
-    compilerOutput.kind,
-  );
+
   const isFailure = compilerOutput.kind !== 'ok';
-
-  if (compilerOutput.kind !== previousOutputKind) {
-    setPreviousOutputKind(compilerOutput.kind);
-    if (isFailure) {
-      startTransition(() => {
-        addTransitionType(EXPAND_ACCORDION_TRANSITION);
-        setTabsOpen(prev => new Set(prev).add('Output'));
-        setActiveTab('Output');
-      });
-    }
-  }
-
   const changedPasses: Set<string> = new Set(['Output', 'HIR']); // Initial and final passes should always be bold
   let lastResult: string = '';
   for (const [passName, results] of compilerOutput.results) {
@@ -312,6 +295,8 @@ function OutputContent({store, compilerOutput}: Props): JSX.Element {
           tabs={tabs}
           activeTab={activeTab}
           onTabChange={setActiveTab}
+          // Display the Output tab on compilation failure
+          activeTabOverride={isFailure ? 'Output' : undefined}
         />
       </ViewTransition>
     );
@@ -330,6 +315,7 @@ function OutputContent({store, compilerOutput}: Props): JSX.Element {
         tabsOpen={tabsOpen}
         tabs={tabs}
         changedPasses={changedPasses}
+        isFailure={isFailure}
       />
     </ViewTransition>
   );
@@ -386,18 +372,12 @@ function TextTabContent({
           loading={''}
           options={{
             ...monacoOptions,
-            scrollbar: {
-              vertical: 'hidden',
-            },
-            dimension: {
-              width: 0,
-              height: 0,
-            },
             readOnly: true,
             lineNumbers: 'off',
             glyphMargin: false,
             // Undocumented see https://github.com/Microsoft/vscode/issues/30795#issuecomment-410998882
-            overviewRulerLanes: 0,
+            lineDecorationsWidth: 0,
+            lineNumbersMinChars: 0,
           }}
         />
       ) : (

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

@@ -32,14 +32,3 @@ export const monacoOptions: Partial<EditorProps['options']> = {
 
   tabSize: 2,
 };
-
-export const monacoConfigOptions: Partial<EditorProps['options']> = {
-  ...monacoOptions,
-  lineNumbers: 'off',
-  renderLineHighlight: 'none',
-  overviewRulerBorder: false,
-  overviewRulerLanes: 0,
-  fontSize: 12,
-  scrollBeyondLastLine: false,
-  glyphMargin: false,
-};

compiler/apps/playground/components/TabbedWindow.tsx

@@ -17,11 +17,15 @@ export default function TabbedWindow({
   tabs,
   activeTab,
   onTabChange,
+  activeTabOverride,
 }: {
   tabs: Map<string, React.ReactNode>;
   activeTab: string;
   onTabChange: (tab: string) => void;
+  activeTabOverride?: string;
 }): React.ReactElement {
+  const currentActiveTab = activeTabOverride ? activeTabOverride : activeTab;
+
   const id = useId();
   const transitionName = `tab-highlight-${id}`;
 
@@ -37,7 +41,7 @@ export default function TabbedWindow({
       <div className="flex flex-col h-full max-w-full">
         <div className="flex p-2 flex-shrink-0">
           {Array.from(tabs.keys()).map(tab => {
-            const isActive = activeTab === tab;
+            const isActive = currentActiveTab === tab;
             return (
               <button
                 key={tab}
@@ -73,7 +77,7 @@ export default function TabbedWindow({
           })}
         </div>
         <div className="flex-1 overflow-hidden w-full h-full">
-          {tabs.get(activeTab)}
+          {tabs.get(currentActiveTab)}
         </div>
       </div>
     </div>

compiler/apps/playground/lib/compilation.ts

@@ -1,308 +0,0 @@
-/**
- * Copyright (c) Meta Platforms, Inc. and affiliates.
- *
- * This source code is licensed under the MIT license found in the
- * LICENSE file in the root directory of this source tree.
- */
-
-import {parse as babelParse, ParseResult} from '@babel/parser';
-import * as HermesParser from 'hermes-parser';
-import * as t from '@babel/types';
-import BabelPluginReactCompiler, {
-  CompilerError,
-  CompilerErrorDetail,
-  CompilerDiagnostic,
-  Effect,
-  ErrorCategory,
-  parseConfigPragmaForTests,
-  ValueKind,
-  type Hook,
-  PluginOptions,
-  CompilerPipelineValue,
-  parsePluginOptions,
-  printReactiveFunctionWithOutlined,
-  printFunctionWithOutlined,
-  type LoggerEvent,
-} from 'babel-plugin-react-compiler';
-import {transformFromAstSync} from '@babel/core';
-import type {
-  CompilerOutput,
-  CompilerTransformOutput,
-  PrintedCompilerPipelineValue,
-} from '../components/Editor/Output';
-
-function parseInput(
-  input: string,
-  language: 'flow' | 'typescript',
-): ParseResult<t.File> {
-  // Extract the first line to quickly check for custom test directives
-  if (language === 'flow') {
-    return HermesParser.parse(input, {
-      babel: true,
-      flow: 'all',
-      sourceType: 'module',
-      enableExperimentalComponentSyntax: true,
-    });
-  } else {
-    return babelParse(input, {
-      plugins: ['typescript', 'jsx'],
-      sourceType: 'module',
-    }) as ParseResult<t.File>;
-  }
-}
-
-function invokeCompiler(
-  source: string,
-  language: 'flow' | 'typescript',
-  options: PluginOptions,
-): CompilerTransformOutput {
-  const ast = parseInput(source, language);
-  let result = transformFromAstSync(ast, source, {
-    filename: '_playgroundFile.js',
-    highlightCode: false,
-    retainLines: true,
-    plugins: [[BabelPluginReactCompiler, options]],
-    ast: true,
-    sourceType: 'module',
-    configFile: false,
-    sourceMaps: true,
-    babelrc: false,
-  });
-  if (result?.ast == null || result?.code == null || result?.map == null) {
-    throw new Error('Expected successful compilation');
-  }
-  return {
-    code: result.code,
-    sourceMaps: result.map,
-    language,
-  };
-}
-
-const COMMON_HOOKS: Array<[string, Hook]> = [
-  [
-    'useFragment',
-    {
-      valueKind: ValueKind.Frozen,
-      effectKind: Effect.Freeze,
-      noAlias: true,
-      transitiveMixedData: true,
-    },
-  ],
-  [
-    'usePaginationFragment',
-    {
-      valueKind: ValueKind.Frozen,
-      effectKind: Effect.Freeze,
-      noAlias: true,
-      transitiveMixedData: true,
-    },
-  ],
-  [
-    'useRefetchableFragment',
-    {
-      valueKind: ValueKind.Frozen,
-      effectKind: Effect.Freeze,
-      noAlias: true,
-      transitiveMixedData: true,
-    },
-  ],
-  [
-    'useLazyLoadQuery',
-    {
-      valueKind: ValueKind.Frozen,
-      effectKind: Effect.Freeze,
-      noAlias: true,
-      transitiveMixedData: true,
-    },
-  ],
-  [
-    'usePreloadedQuery',
-    {
-      valueKind: ValueKind.Frozen,
-      effectKind: Effect.Freeze,
-      noAlias: true,
-      transitiveMixedData: true,
-    },
-  ],
-];
-
-function parseOptions(
-  source: string,
-  mode: 'compiler' | 'linter',
-  configOverrides: string,
-): PluginOptions {
-  // Extract the first line to quickly check for custom test directives
-  const pragma = source.substring(0, source.indexOf('\n'));
-
-  const parsedPragmaOptions = parseConfigPragmaForTests(pragma, {
-    compilationMode: 'infer',
-    environment:
-      mode === 'linter'
-        ? {
-            // enabled in compiler
-            validateRefAccessDuringRender: false,
-            // enabled in linter
-            validateNoSetStateInRender: true,
-            validateNoSetStateInEffects: true,
-            validateNoJSXInTryStatements: true,
-            validateNoImpureFunctionsInRender: true,
-            validateStaticComponents: true,
-            validateNoFreezingKnownMutableFunctions: true,
-            validateNoVoidUseMemo: true,
-          }
-        : {
-            /* use defaults for compiler mode */
-          },
-  });
-
-  // Parse config overrides from config editor
-  let configOverrideOptions: any = {};
-  const configMatch = configOverrides.match(/^\s*import.*?\n\n\((.*)\)/s);
-  if (configOverrides.trim()) {
-    if (configMatch && configMatch[1]) {
-      const configString = configMatch[1].replace(/satisfies.*$/, '').trim();
-      configOverrideOptions = new Function(`return (${configString})`)();
-    } else {
-      throw new Error('Invalid override format');
-    }
-  }
-
-  const opts: PluginOptions = parsePluginOptions({
-    ...parsedPragmaOptions,
-    ...configOverrideOptions,
-    environment: {
-      ...parsedPragmaOptions.environment,
-      ...configOverrideOptions.environment,
-      customHooks: new Map([...COMMON_HOOKS]),
-    },
-  });
-
-  return opts;
-}
-
-export function compile(
-  source: string,
-  mode: 'compiler' | 'linter',
-  configOverrides: string,
-): [CompilerOutput, 'flow' | 'typescript', PluginOptions | null] {
-  const results = new Map<string, Array<PrintedCompilerPipelineValue>>();
-  const error = new CompilerError();
-  const otherErrors: Array<CompilerErrorDetail | CompilerDiagnostic> = [];
-  const upsert: (result: PrintedCompilerPipelineValue) => void = result => {
-    const entry = results.get(result.name);
-    if (Array.isArray(entry)) {
-      entry.push(result);
-    } else {
-      results.set(result.name, [result]);
-    }
-  };
-  let language: 'flow' | 'typescript';
-  if (source.match(/\@flow/)) {
-    language = 'flow';
-  } else {
-    language = 'typescript';
-  }
-  let transformOutput;
-
-  let baseOpts: PluginOptions | null = null;
-  try {
-    baseOpts = parseOptions(source, mode, configOverrides);
-  } catch (err) {
-    error.details.push(
-      new CompilerErrorDetail({
-        category: ErrorCategory.Config,
-        reason: `Unexpected failure when transforming configs! \n${err}`,
-        loc: null,
-        suggestions: null,
-      }),
-    );
-  }
-  if (baseOpts) {
-    try {
-      const logIR = (result: CompilerPipelineValue): void => {
-        switch (result.kind) {
-          case 'ast': {
-            break;
-          }
-          case 'hir': {
-            upsert({
-              kind: 'hir',
-              fnName: result.value.id,
-              name: result.name,
-              value: printFunctionWithOutlined(result.value),
-            });
-            break;
-          }
-          case 'reactive': {
-            upsert({
-              kind: 'reactive',
-              fnName: result.value.id,
-              name: result.name,
-              value: printReactiveFunctionWithOutlined(result.value),
-            });
-            break;
-          }
-          case 'debug': {
-            upsert({
-              kind: 'debug',
-              fnName: null,
-              name: result.name,
-              value: result.value,
-            });
-            break;
-          }
-          default: {
-            const _: never = result;
-            throw new Error(`Unhandled result ${result}`);
-          }
-        }
-      };
-      // Add logger options to the parsed options
-      const opts = {
-        ...baseOpts,
-        logger: {
-          debugLogIRs: logIR,
-          logEvent: (_filename: string | null, event: LoggerEvent): void => {
-            if (event.kind === 'CompileError') {
-              otherErrors.push(event.detail);
-            }
-          },
-        },
-      };
-      transformOutput = invokeCompiler(source, language, opts);
-    } catch (err) {
-      /**
-       * error might be an invariant violation or other runtime error
-       * (i.e. object shape that is not CompilerError)
-       */
-      if (err instanceof CompilerError && err.details.length > 0) {
-        error.merge(err);
-      } else {
-        /**
-         * Handle unexpected failures by logging (to get a stack trace)
-         * and reporting
-         */
-        error.details.push(
-          new CompilerErrorDetail({
-            category: ErrorCategory.Invariant,
-            reason: `Unexpected failure when transforming input! \n${err}`,
-            loc: null,
-            suggestions: null,
-          }),
-        );
-      }
-    }
-  }
-  // Only include logger errors if there weren't other errors
-  if (!error.hasErrors() && otherErrors.length !== 0) {
-    otherErrors.forEach(e => error.details.push(e));
-  }
-  if (error.hasErrors() || !transformOutput) {
-    return [{kind: 'err', results, error}, language, baseOpts];
-  }
-  return [
-    {kind: 'ok', results, transformOutput, errors: error.details},
-    language,
-    baseOpts,
-  ];
-}

compiler/apps/playground/styles/globals.css

@@ -124,11 +124,3 @@
 ::view-transition-group(.expand-accordion) {
   overflow: clip;
 }
-
-/**
- * For some reason, the original Monaco editor is still visible to the
- * left of the DiffEditor. This is a workaround for better visual clarity.
- */
-.monaco-diff-editor .editor.original{
-  visibility: hidden !important;
-}

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

@@ -52,8 +52,8 @@
     "react-dom": "0.0.0-experimental-4beb1fd8-20241118",
     "ts-jest": "^29.1.1",
     "ts-node": "^10.9.2",
-    "zod": "^3.25.0 || ^4.0.0",
-    "zod-validation-error": "^3.5.0 || ^4.0.0"
+    "zod": "^3.22.4",
+    "zod-validation-error": "^2.1.0"
   },
   "resolutions": {
     "./**/@babel/parser": "7.7.4",

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

@@ -536,8 +536,7 @@ function printErrorSummary(category: ErrorCategory, message: string): string {
     case ErrorCategory.StaticComponents:
     case ErrorCategory.Suppression:
     case ErrorCategory.Syntax:
-    case ErrorCategory.UseMemo:
-    case ErrorCategory.VoidUseMemo: {
+    case ErrorCategory.UseMemo: {
       heading = 'Error';
       break;
     }
@@ -583,10 +582,6 @@ export enum ErrorCategory {
    * Checking for valid usage of manual memoization
    */
   UseMemo = 'UseMemo',
-  /**
-   * Checking that useMemos always return a value
-   */
-  VoidUseMemo = 'VoidUseMemo',
   /**
    * Checking for higher order functions acting as factories for components/hooks
    */
@@ -674,21 +669,6 @@ export enum ErrorCategory {
   FBT = 'FBT',
 }
 
-export enum LintRulePreset {
-  /**
-   * Rules that are stable and included in the `recommended` preset.
-   */
-  Recommended = 'recommended',
-  /**
-   * Rules that are more experimental and only included in the `recommended-latest` preset.
-   */
-  RecommendedLatest = 'recommended-latest',
-  /**
-   * Rules that are disabled.
-   */
-  Off = 'off',
-}
-
 export type LintRule = {
   // Stores the category the rule corresponds to, used to filter errors when reporting
   category: ErrorCategory;
@@ -709,14 +689,15 @@ export type LintRule = {
   description: string;
 
   /**
-   * Configures the preset in which the rule is enabled. If 'off', the rule will not be included in
-   * any preset.
+   * If true, this rule will automatically appear in the default, "recommended" ESLint
+   * rule set. Otherwise it will be part of an `allRules` export that developers can
+   * use to opt-in to showing output of all possible rules.
    *
    * NOTE: not all validations are enabled by default! Setting this flag only affects
    * whether a given rule is part of the recommended set. The corresponding validation
    * also should be enabled by default if you want the error to actually show up!
    */
-  preset: LintRulePreset;
+  recommended: boolean;
 };
 
 const RULE_NAME_PATTERN = /^[a-z]+(-[a-z]+)*$/;
@@ -739,7 +720,7 @@ function getRuleForCategoryImpl(category: ErrorCategory): LintRule {
         name: 'automatic-effect-dependencies',
         description:
           'Verifies that automatic effect dependencies are compiled if opted-in',
-        preset: LintRulePreset.Off,
+        recommended: false,
       };
     }
     case ErrorCategory.CapitalizedCalls: {
@@ -749,7 +730,7 @@ function getRuleForCategoryImpl(category: ErrorCategory): LintRule {
         name: 'capitalized-calls',
         description:
           'Validates against calling capitalized functions/methods instead of using JSX',
-        preset: LintRulePreset.Off,
+        recommended: false,
       };
     }
     case ErrorCategory.Config: {
@@ -758,7 +739,7 @@ function getRuleForCategoryImpl(category: ErrorCategory): LintRule {
         severity: ErrorSeverity.Error,
         name: 'config',
         description: 'Validates the compiler configuration options',
-        preset: LintRulePreset.Recommended,
+        recommended: true,
       };
     }
     case ErrorCategory.EffectDependencies: {
@@ -767,7 +748,7 @@ function getRuleForCategoryImpl(category: ErrorCategory): LintRule {
         severity: ErrorSeverity.Error,
         name: 'memoized-effect-dependencies',
         description: 'Validates that effect dependencies are memoized',
-        preset: LintRulePreset.Off,
+        recommended: false,
       };
     }
     case ErrorCategory.EffectDerivationsOfState: {
@@ -777,7 +758,7 @@ function getRuleForCategoryImpl(category: ErrorCategory): LintRule {
         name: 'no-deriving-state-in-effects',
         description:
           'Validates against deriving values from state in an effect',
-        preset: LintRulePreset.Off,
+        recommended: false,
       };
     }
     case ErrorCategory.EffectSetState: {
@@ -787,7 +768,7 @@ function getRuleForCategoryImpl(category: ErrorCategory): LintRule {
         name: 'set-state-in-effect',
         description:
           'Validates against calling setState synchronously in an effect, which can lead to re-renders that degrade performance',
-        preset: LintRulePreset.Recommended,
+        recommended: true,
       };
     }
     case ErrorCategory.ErrorBoundaries: {
@@ -797,7 +778,7 @@ function getRuleForCategoryImpl(category: ErrorCategory): LintRule {
         name: 'error-boundaries',
         description:
           'Validates usage of error boundaries instead of try/catch for errors in child components',
-        preset: LintRulePreset.Recommended,
+        recommended: true,
       };
     }
     case ErrorCategory.Factories: {
@@ -808,7 +789,7 @@ function getRuleForCategoryImpl(category: ErrorCategory): LintRule {
         description:
           'Validates against higher order functions defining nested components or hooks. ' +
           'Components and hooks should be defined at the module level',
-        preset: LintRulePreset.Recommended,
+        recommended: true,
       };
     }
     case ErrorCategory.FBT: {
@@ -817,7 +798,7 @@ function getRuleForCategoryImpl(category: ErrorCategory): LintRule {
         severity: ErrorSeverity.Error,
         name: 'fbt',
         description: 'Validates usage of fbt',
-        preset: LintRulePreset.Off,
+        recommended: false,
       };
     }
     case ErrorCategory.Fire: {
@@ -826,7 +807,7 @@ function getRuleForCategoryImpl(category: ErrorCategory): LintRule {
         severity: ErrorSeverity.Error,
         name: 'fire',
         description: 'Validates usage of `fire`',
-        preset: LintRulePreset.Off,
+        recommended: false,
       };
     }
     case ErrorCategory.Gating: {
@@ -836,7 +817,7 @@ function getRuleForCategoryImpl(category: ErrorCategory): LintRule {
         name: 'gating',
         description:
           'Validates configuration of [gating mode](https://react.dev/reference/react-compiler/gating)',
-        preset: LintRulePreset.Recommended,
+        recommended: true,
       };
     }
     case ErrorCategory.Globals: {
@@ -847,7 +828,7 @@ function getRuleForCategoryImpl(category: ErrorCategory): LintRule {
         description:
           'Validates against assignment/mutation of globals during render, part of ensuring that ' +
           '[side effects must render outside of render](https://react.dev/reference/rules/components-and-hooks-must-be-pure#side-effects-must-run-outside-of-render)',
-        preset: LintRulePreset.Recommended,
+        recommended: true,
       };
     }
     case ErrorCategory.Hooks: {
@@ -861,7 +842,7 @@ function getRuleForCategoryImpl(category: ErrorCategory): LintRule {
          * We need to dedeupe these (moving the remaining bits into the compiler) and then enable
          * this rule.
          */
-        preset: LintRulePreset.Off,
+        recommended: false,
       };
     }
     case ErrorCategory.Immutability: {
@@ -871,7 +852,7 @@ function getRuleForCategoryImpl(category: ErrorCategory): LintRule {
         name: 'immutability',
         description:
           'Validates against mutating props, state, and other values that [are immutable](https://react.dev/reference/rules/components-and-hooks-must-be-pure#props-and-state-are-immutable)',
-        preset: LintRulePreset.Recommended,
+        recommended: true,
       };
     }
     case ErrorCategory.Invariant: {
@@ -880,7 +861,7 @@ function getRuleForCategoryImpl(category: ErrorCategory): LintRule {
         severity: ErrorSeverity.Error,
         name: 'invariant',
         description: 'Internal invariants',
-        preset: LintRulePreset.Off,
+        recommended: false,
       };
     }
     case ErrorCategory.PreserveManualMemo: {
@@ -892,7 +873,7 @@ function getRuleForCategoryImpl(category: ErrorCategory): LintRule {
           'Validates that existing manual memoized is preserved by the compiler. ' +
           'React Compiler will only compile components and hooks if its inference ' +
           '[matches or exceeds the existing manual memoization](https://react.dev/learn/react-compiler/introduction#what-should-i-do-about-usememo-usecallback-and-reactmemo)',
-        preset: LintRulePreset.Recommended,
+        recommended: true,
       };
     }
     case ErrorCategory.Purity: {
@@ -902,7 +883,7 @@ function getRuleForCategoryImpl(category: ErrorCategory): LintRule {
         name: 'purity',
         description:
           'Validates that [components/hooks are pure](https://react.dev/reference/rules/components-and-hooks-must-be-pure) by checking that they do not call known-impure functions',
-        preset: LintRulePreset.Recommended,
+        recommended: true,
       };
     }
     case ErrorCategory.Refs: {
@@ -912,7 +893,7 @@ function getRuleForCategoryImpl(category: ErrorCategory): LintRule {
         name: 'refs',
         description:
           'Validates correct usage of refs, not reading/writing during render. See the "pitfalls" section in [`useRef()` usage](https://react.dev/reference/react/useRef#usage)',
-        preset: LintRulePreset.Recommended,
+        recommended: true,
       };
     }
     case ErrorCategory.RenderSetState: {
@@ -922,7 +903,7 @@ function getRuleForCategoryImpl(category: ErrorCategory): LintRule {
         name: 'set-state-in-render',
         description:
           'Validates against setting state during render, which can trigger additional renders and potential infinite render loops',
-        preset: LintRulePreset.Recommended,
+        recommended: true,
       };
     }
     case ErrorCategory.StaticComponents: {
@@ -932,7 +913,7 @@ function getRuleForCategoryImpl(category: ErrorCategory): LintRule {
         name: 'static-components',
         description:
           'Validates that components are static, not recreated every render. Components that are recreated dynamically can reset state and trigger excessive re-rendering',
-        preset: LintRulePreset.Recommended,
+        recommended: true,
       };
     }
     case ErrorCategory.Suppression: {
@@ -941,7 +922,7 @@ function getRuleForCategoryImpl(category: ErrorCategory): LintRule {
         severity: ErrorSeverity.Error,
         name: 'rule-suppression',
         description: 'Validates against suppression of other rules',
-        preset: LintRulePreset.Off,
+        recommended: false,
       };
     }
     case ErrorCategory.Syntax: {
@@ -950,7 +931,7 @@ function getRuleForCategoryImpl(category: ErrorCategory): LintRule {
         severity: ErrorSeverity.Error,
         name: 'syntax',
         description: 'Validates against invalid syntax',
-        preset: LintRulePreset.Off,
+        recommended: false,
       };
     }
     case ErrorCategory.Todo: {
@@ -959,7 +940,7 @@ function getRuleForCategoryImpl(category: ErrorCategory): LintRule {
         severity: ErrorSeverity.Hint,
         name: 'todo',
         description: 'Unimplemented features',
-        preset: LintRulePreset.Off,
+        recommended: false,
       };
     }
     case ErrorCategory.UnsupportedSyntax: {
@@ -969,7 +950,7 @@ function getRuleForCategoryImpl(category: ErrorCategory): LintRule {
         name: 'unsupported-syntax',
         description:
           'Validates against syntax that we do not plan to support in React Compiler',
-        preset: LintRulePreset.Recommended,
+        recommended: true,
       };
     }
     case ErrorCategory.UseMemo: {
@@ -979,17 +960,7 @@ function getRuleForCategoryImpl(category: ErrorCategory): LintRule {
         name: 'use-memo',
         description:
           'Validates usage of the useMemo() hook against common mistakes. See [`useMemo()` docs](https://react.dev/reference/react/useMemo) for more information.',
-        preset: LintRulePreset.Recommended,
-      };
-    }
-    case ErrorCategory.VoidUseMemo: {
-      return {
-        category,
-        severity: ErrorSeverity.Error,
-        name: 'void-use-memo',
-        description:
-          'Validates that useMemos always return a value. See [`useMemo()` docs](https://react.dev/reference/react/useMemo) for more information.',
-        preset: LintRulePreset.RecommendedLatest,
+        recommended: true,
       };
     }
     case ErrorCategory.IncompatibleLibrary: {
@@ -999,7 +970,7 @@ function getRuleForCategoryImpl(category: ErrorCategory): LintRule {
         name: 'incompatible-library',
         description:
           'Validates against usage of libraries which are incompatible with memoization (manual or automatic)',
-        preset: LintRulePreset.Recommended,
+        recommended: true,
       };
     }
     default: {

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

@@ -6,7 +6,7 @@
  */
 
 import * as t from '@babel/types';
-import {z} from 'zod/v4';
+import {z} from 'zod';
 import {
   CompilerDiagnostic,
   CompilerError,
@@ -20,7 +20,7 @@ import {
   tryParseExternalFunction,
 } from '../HIR/Environment';
 import {hasOwnProperty} from '../Utils/utils';
-import {fromZodError} from 'zod-validation-error/v4';
+import {fromZodError} from 'zod-validation-error';
 import {CompilerPipelineValue} from './Pipeline';
 
 const PanicThresholdOptionsSchema = z.enum([

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

@@ -6,8 +6,8 @@
  */
 
 import * as t from '@babel/types';
-import {ZodError, z} from 'zod/v4';
-import {fromZodError} from 'zod-validation-error/v4';
+import {ZodError, z} from 'zod';
+import {fromZodError} from 'zod-validation-error';
 import {CompilerError} from '../CompilerError';
 import {Logger, ProgramContext} from '../Entrypoint';
 import {Err, Ok, Result} from '../Utils/Result';
@@ -159,7 +159,7 @@ export const EnvironmentConfigSchema = z.object({
    * A function that, given the name of a module, can optionally return a description
    * of that module's type signature.
    */
-  moduleTypeProvider: z.nullable(z.any()).default(null),
+  moduleTypeProvider: z.nullable(z.function().args(z.string())).default(null),
 
   /**
    * A list of functions which the application compiles as macros, where
@@ -210,7 +210,7 @@ export const EnvironmentConfigSchema = z.object({
    * that if a useEffect or useCallback references a function value, that function value will be
    * considered frozen, and in turn all of its referenced variables will be considered frozen as well.
    */
-  enablePreserveExistingMemoizationGuarantees: z.boolean().default(true),
+  enablePreserveExistingMemoizationGuarantees: z.boolean().default(false),
 
   /**
    * Validates that all useMemo/useCallback values are also memoized by Forget. This mode can be
@@ -249,7 +249,7 @@ export const EnvironmentConfigSchema = z.object({
    * Allows specifying a function that can populate HIR with type information from
    * Flow
    */
-  flowTypeProvider: z.nullable(z.any()).default(null),
+  flowTypeProvider: z.nullable(z.function().args(z.string())).default(null),
 
   /**
    * Enables inference of optional dependency chains. Without this flag
@@ -906,12 +906,6 @@ export class Environment {
       if (moduleTypeProvider == null) {
         return null;
       }
-      if (typeof moduleTypeProvider !== 'function') {
-        CompilerError.throwInvalidConfig({
-          reason: `Expected a function for \`moduleTypeProvider\``,
-          loc,
-        });
-      }
       const unparsedModuleConfig = moduleTypeProvider(moduleName);
       if (unparsedModuleConfig != null) {
         const parsedModuleConfig = TypeSchema.safeParse(unparsedModuleConfig);

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

@@ -16,7 +16,7 @@ import {assertExhaustive} from '../Utils/utils';
 import {Environment, ReactFunctionType} from './Environment';
 import type {HookKind} from './ObjectShape';
 import {Type, makeType} from './Types';
-import {z} from 'zod/v4';
+import {z} from 'zod';
 import type {AliasingEffect} from '../Inference/AliasingEffects';
 import {isReservedWord} from '../Utils/Keyword';
 import {Err, Ok, Result} from '../Utils/Result';

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

@@ -6,7 +6,7 @@
  */
 
 import {isValidIdentifier} from '@babel/types';
-import {z} from 'zod/v4';
+import {z} from 'zod';
 import {Effect, ValueKind} from '..';
 import {
   EffectSchema,

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

@@ -454,13 +454,13 @@ export function dropManualMemoization(
               if (!hasNonVoidReturn(funcToCheck.loweredFunc.func)) {
                 errors.pushDiagnostic(
                   CompilerDiagnostic.create({
-                    category: ErrorCategory.VoidUseMemo,
+                    category: ErrorCategory.UseMemo,
                     reason: 'useMemo() callbacks must return a value',
                     description: `This ${
                       manualMemo.loadInstr.value.kind === 'PropertyLoad'
-                        ? 'React.useMemo()'
-                        : 'useMemo()'
-                    } callback doesn't return a value. useMemo() is for computing and caching values, not for arbitrary side effects`,
+                        ? 'React.useMemo'
+                        : 'useMemo'
+                    } callback doesn't return a value. useMemo is for computing and caching values, not for arbitrary side effects`,
                     suggestions: null,
                   }).withDetails({
                     kind: 'error',

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

@@ -7,17 +7,14 @@
 
 import {
   HIRFunction,
-  Identifier,
   IdentifierId,
-  InstructionValue,
   makeInstructionId,
   MutableRange,
   Place,
-  ReactiveScope,
+  ReactiveValue,
 } from '../HIR';
 import {Macro, MacroMethod} from '../HIR/Environment';
-import {eachInstructionValueOperand} from '../HIR/visitors';
-import {Iterable_some} from '../Utils/utils';
+import {eachReactiveValueOperand} from './visitors';
 
 /**
  * This pass supports the `fbt` translation system (https://facebook.github.io/fbt/)
@@ -51,49 +48,24 @@ export function memoizeFbtAndMacroOperandsInSameScope(
     ...Array.from(FBT_TAGS).map((tag): Macro => [tag, []]),
     ...(fn.env.config.customMacros ?? []),
   ]);
-  /**
-   * Set of all identifiers that load fbt or other macro functions or their nested
-   * properties, as well as values known to be the results of invoking macros
-   */
-  const macroTagsCalls: Set<IdentifierId> = new Set();
-  /**
-   * Mapping of lvalue => list of operands for all expressions where either
-   * the lvalue is a known fbt/macro call and/or the operands transitively
-   * contain fbt/macro calls.
-   *
-   * This is the key data structure that powers the scope merging: we start
-   * at the lvalues and merge operands into the lvalue's scope.
-   */
-  const macroValues: Map<Identifier, Array<Identifier>> = new Map();
-  // Tracks methods loaded from macros, like fbt.param or idx.foo
+  const fbtValues: Set<IdentifierId> = new Set();
   const macroMethods = new Map<IdentifierId, Array<Array<MacroMethod>>>();
-
-  visit(fn, fbtMacroTags, macroTagsCalls, macroMethods, macroValues);
-
-  for (const root of macroValues.keys()) {
-    const scope = root.scope;
-    if (scope == null) {
-      continue;
+  while (true) {
+    let vsize = fbtValues.size;
+    let msize = macroMethods.size;
+    visit(fn, fbtMacroTags, fbtValues, macroMethods);
+    if (vsize === fbtValues.size && msize === macroMethods.size) {
+      break;
     }
-    // Merge the operands into the same scope if this is a known macro invocation
-    if (!macroTagsCalls.has(root.id)) {
-      continue;
-    }
-    mergeScopes(root, scope, macroValues, macroTagsCalls);
   }
-
-  return macroTagsCalls;
+  return fbtValues;
 }
 
 export const FBT_TAGS: Set<string> = new Set([
   'fbt',
   'fbt:param',
-  'fbt:enum',
-  'fbt:plural',
   'fbs',
   'fbs:param',
-  'fbs:enum',
-  'fbs:plural',
 ]);
 export const SINGLE_CHILD_FBT_TAGS: Set<string> = new Set([
   'fbt:param',
@@ -103,22 +75,10 @@ export const SINGLE_CHILD_FBT_TAGS: Set<string> = new Set([
 function visit(
   fn: HIRFunction,
   fbtMacroTags: Set<Macro>,
-  macroTagsCalls: Set<IdentifierId>,
+  fbtValues: Set<IdentifierId>,
   macroMethods: Map<IdentifierId, Array<Array<MacroMethod>>>,
-  macroValues: Map<Identifier, Array<Identifier>>,
 ): void {
   for (const [, block] of fn.body.blocks) {
-    for (const phi of block.phis) {
-      const macroOperands: Array<Identifier> = [];
-      for (const operand of phi.operands.values()) {
-        if (macroValues.has(operand.identifier)) {
-          macroOperands.push(operand.identifier);
-        }
-      }
-      if (macroOperands.length !== 0) {
-        macroValues.set(phi.place.identifier, macroOperands);
-      }
-    }
     for (const instruction of block.instructions) {
       const {lvalue, value} = instruction;
       if (lvalue === null) {
@@ -133,13 +93,13 @@ function visit(
          * We don't distinguish between tag names and strings, so record
          * all `fbt` string literals in case they are used as a jsx tag.
          */
-        macroTagsCalls.add(lvalue.identifier.id);
+        fbtValues.add(lvalue.identifier.id);
       } else if (
         value.kind === 'LoadGlobal' &&
         matchesExactTag(value.binding.name, fbtMacroTags)
       ) {
         // Record references to `fbt` as a global
-        macroTagsCalls.add(lvalue.identifier.id);
+        fbtValues.add(lvalue.identifier.id);
       } else if (
         value.kind === 'LoadGlobal' &&
         matchTagRoot(value.binding.name, fbtMacroTags) !== null
@@ -161,66 +121,84 @@ function visit(
             if (method.length > 1) {
               newMethods.push(method.slice(1));
             } else {
-              macroTagsCalls.add(lvalue.identifier.id);
+              fbtValues.add(lvalue.identifier.id);
             }
           }
         }
         if (newMethods.length > 0) {
           macroMethods.set(lvalue.identifier.id, newMethods);
         }
-      } else if (
-        value.kind === 'PropertyLoad' &&
-        macroTagsCalls.has(value.object.identifier.id)
-      ) {
-        macroTagsCalls.add(lvalue.identifier.id);
-      } else if (
-        isFbtJsxExpression(fbtMacroTags, macroTagsCalls, value) ||
-        isFbtJsxChild(macroTagsCalls, lvalue, value) ||
-        isFbtCallExpression(macroTagsCalls, value)
-      ) {
-        macroTagsCalls.add(lvalue.identifier.id);
-        macroValues.set(
-          lvalue.identifier,
-          Array.from(
-            eachInstructionValueOperand(value),
-            operand => operand.identifier,
-          ),
-        );
-      } else if (
-        Iterable_some(eachInstructionValueOperand(value), operand =>
-          macroValues.has(operand.identifier),
-        )
-      ) {
-        const macroOperands: Array<Identifier> = [];
-        for (const operand of eachInstructionValueOperand(value)) {
-          if (macroValues.has(operand.identifier)) {
-            macroOperands.push(operand.identifier);
-          }
+      } else if (isFbtCallExpression(fbtValues, value)) {
+        const fbtScope = lvalue.identifier.scope;
+        if (fbtScope === null) {
+          continue;
+        }
+
+        /*
+         * if the JSX element's tag was `fbt`, mark all its operands
+         * to ensure that they end up in the same scope as the jsx element
+         * itself.
+         */
+        for (const operand of eachReactiveValueOperand(value)) {
+          operand.identifier.scope = fbtScope;
+
+          // Expand the jsx element's range to account for its operands
+          expandFbtScopeRange(fbtScope.range, operand.identifier.mutableRange);
+          fbtValues.add(operand.identifier.id);
+        }
+      } else if (
+        isFbtJsxExpression(fbtMacroTags, fbtValues, value) ||
+        isFbtJsxChild(fbtValues, lvalue, value)
+      ) {
+        const fbtScope = lvalue.identifier.scope;
+        if (fbtScope === null) {
+          continue;
+        }
+
+        /*
+         * if the JSX element's tag was `fbt`, mark all its operands
+         * to ensure that they end up in the same scope as the jsx element
+         * itself.
+         */
+        for (const operand of eachReactiveValueOperand(value)) {
+          operand.identifier.scope = fbtScope;
+
+          // Expand the jsx element's range to account for its operands
+          expandFbtScopeRange(fbtScope.range, operand.identifier.mutableRange);
+
+          /*
+           * NOTE: we add the operands as fbt values so that they are also
+           * grouped with this expression
+           */
+          fbtValues.add(operand.identifier.id);
+        }
+      } else if (fbtValues.has(lvalue.identifier.id)) {
+        const fbtScope = lvalue.identifier.scope;
+        if (fbtScope === null) {
+          return;
+        }
+
+        for (const operand of eachReactiveValueOperand(value)) {
+          if (
+            operand.identifier.name !== null &&
+            operand.identifier.name.kind === 'named'
+          ) {
+            /*
+             * named identifiers were already locals, we only have to force temporaries
+             * into the same scope
+             */
+            continue;
+          }
+          operand.identifier.scope = fbtScope;
+
+          // Expand the jsx element's range to account for its operands
+          expandFbtScopeRange(fbtScope.range, operand.identifier.mutableRange);
         }
-        macroValues.set(lvalue.identifier, macroOperands);
       }
     }
   }
 }
 
-function mergeScopes(
-  root: Identifier,
-  scope: ReactiveScope,
-  macroValues: Map<Identifier, Array<Identifier>>,
-  macroTagsCalls: Set<IdentifierId>,
-): void {
-  const operands = macroValues.get(root);
-  if (operands == null) {
-    return;
-  }
-  for (const operand of operands) {
-    operand.scope = scope;
-    expandFbtScopeRange(scope.range, operand.mutableRange);
-    macroTagsCalls.add(operand.id);
-    mergeScopes(operand, scope, macroValues, macroTagsCalls);
-  }
-}
-
 function matchesExactTag(s: string, tags: Set<Macro>): boolean {
   return Array.from(tags).some(macro =>
     typeof macro === 'string'
@@ -251,40 +229,39 @@ function matchTagRoot(
 }
 
 function isFbtCallExpression(
-  macroTagsCalls: Set<IdentifierId>,
-  value: InstructionValue,
+  fbtValues: Set<IdentifierId>,
+  value: ReactiveValue,
 ): boolean {
   return (
     (value.kind === 'CallExpression' &&
-      macroTagsCalls.has(value.callee.identifier.id)) ||
-    (value.kind === 'MethodCall' &&
-      macroTagsCalls.has(value.property.identifier.id))
+      fbtValues.has(value.callee.identifier.id)) ||
+    (value.kind === 'MethodCall' && fbtValues.has(value.property.identifier.id))
   );
 }
 
 function isFbtJsxExpression(
   fbtMacroTags: Set<Macro>,
-  macroTagsCalls: Set<IdentifierId>,
-  value: InstructionValue,
+  fbtValues: Set<IdentifierId>,
+  value: ReactiveValue,
 ): boolean {
   return (
     value.kind === 'JsxExpression' &&
     ((value.tag.kind === 'Identifier' &&
-      macroTagsCalls.has(value.tag.identifier.id)) ||
+      fbtValues.has(value.tag.identifier.id)) ||
       (value.tag.kind === 'BuiltinTag' &&
         matchesExactTag(value.tag.name, fbtMacroTags)))
   );
 }
 
 function isFbtJsxChild(
-  macroTagsCalls: Set<IdentifierId>,
+  fbtValues: Set<IdentifierId>,
   lvalue: Place | null,
-  value: InstructionValue,
+  value: ReactiveValue,
 ): boolean {
   return (
     (value.kind === 'JsxExpression' || value.kind === 'JsxFragment') &&
     lvalue !== null &&
-    macroTagsCalls.has(lvalue.identifier.id)
+    fbtValues.has(lvalue.identifier.id)
   );
 }
 

compiler/packages/babel-plugin-react-compiler/src/TypeInference/InferTypes.ts

@@ -393,7 +393,7 @@ function* generateInstructionTypes(
               shapeId: BuiltInArrayId,
             });
           } else {
-            continue;
+            break;
           }
         }
       } else {

compiler/packages/babel-plugin-react-compiler/src/Utils/TestUtils.ts

@@ -5,7 +5,7 @@
  * LICENSE file in the root directory of this source tree.
  */
 
-import {fromZodError} from 'zod-validation-error/v4';
+import {fromZodError} from 'zod-validation-error';
 import {CompilerError} from '../CompilerError';
 import {
   CompilationMode,

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

@@ -10,16 +10,7 @@ import {
   CompilerError,
   ErrorCategory,
 } from '../CompilerError';
-import {
-  FunctionExpression,
-  HIRFunction,
-  IdentifierId,
-  SourceLocation,
-} from '../HIR';
-import {
-  eachInstructionValueOperand,
-  eachTerminalOperand,
-} from '../HIR/visitors';
+import {FunctionExpression, HIRFunction, IdentifierId} from '../HIR';
 import {Result} from '../Utils/Result';
 
 export function validateUseMemo(fn: HIRFunction): Result<void, CompilerError> {
@@ -27,19 +18,8 @@ export function validateUseMemo(fn: HIRFunction): Result<void, CompilerError> {
   const useMemos = new Set<IdentifierId>();
   const react = new Set<IdentifierId>();
   const functions = new Map<IdentifierId, FunctionExpression>();
-  const unusedUseMemos = new Map<IdentifierId, SourceLocation>();
   for (const [, block] of fn.body.blocks) {
     for (const {lvalue, value} of block.instructions) {
-      if (unusedUseMemos.size !== 0) {
-        /**
-         * Most of the time useMemo results are referenced immediately. Don't bother
-         * scanning instruction operands for useMemos unless there is an as-yet-unused
-         * useMemo.
-         */
-        for (const operand of eachInstructionValueOperand(value)) {
-          unusedUseMemos.delete(operand.identifier.id);
-        }
-      }
       switch (value.kind) {
         case 'LoadGlobal': {
           if (value.binding.name === 'useMemo') {
@@ -65,8 +45,10 @@ export function validateUseMemo(fn: HIRFunction): Result<void, CompilerError> {
         case 'CallExpression': {
           // Is the function being called useMemo, with at least 1 argument?
           const callee =
-            value.kind === 'CallExpression' ? value.callee : value.property;
-          const isUseMemo = useMemos.has(callee.identifier.id);
+            value.kind === 'CallExpression'
+              ? value.callee.identifier.id
+              : value.property.identifier.id;
+          const isUseMemo = useMemos.has(callee);
           if (!isUseMemo || value.args.length === 0) {
             continue;
           }
@@ -122,73 +104,10 @@ export function validateUseMemo(fn: HIRFunction): Result<void, CompilerError> {
             );
           }
 
-          validateNoContextVariableAssignment(body.loweredFunc.func, errors);
-
-          if (fn.env.config.validateNoVoidUseMemo) {
-            unusedUseMemos.set(lvalue.identifier.id, callee.loc);
-          }
           break;
         }
       }
     }
-    if (unusedUseMemos.size !== 0) {
-      for (const operand of eachTerminalOperand(block.terminal)) {
-        unusedUseMemos.delete(operand.identifier.id);
-      }
-    }
-  }
-  if (unusedUseMemos.size !== 0) {
-    /**
-     * Basic check for unused memos, where the result of the call is never referenced. This runs
-     * before DCE so it's more of an AST-level check that something, _anything_, cares about the value.
-     *
-     * This is easy to defeat with e.g. `const _ = useMemo(...)` but it at least gives us something to teach.
-     * Even a DCE-based version could be bypassed with `noop(useMemo(...))`.
-     */
-    for (const loc of unusedUseMemos.values()) {
-      errors.pushDiagnostic(
-        CompilerDiagnostic.create({
-          category: ErrorCategory.VoidUseMemo,
-          reason: 'Unused useMemo()',
-          description: `This useMemo() value is unused. useMemo() is for computing and caching values, not for arbitrary side effects`,
-          suggestions: null,
-        }).withDetails({
-          kind: 'error',
-          loc,
-          message: 'useMemo() result is unused',
-        }),
-      );
-    }
   }
   return errors.asResult();
 }
-
-function validateNoContextVariableAssignment(
-  fn: HIRFunction,
-  errors: CompilerError,
-): void {
-  for (const block of fn.body.blocks.values()) {
-    for (const instr of block.instructions) {
-      const value = instr.value;
-      switch (value.kind) {
-        case 'StoreContext': {
-          errors.pushDiagnostic(
-            CompilerDiagnostic.create({
-              category: ErrorCategory.UseMemo,
-              reason:
-                'useMemo() callbacks may not reassign variables declared outside of the callback',
-              description:
-                'useMemo() callbacks must be pure functions and cannot reassign variables defined outside of the callback function',
-              suggestions: null,
-            }).withDetails({
-              kind: 'error',
-              loc: value.lvalue.place.loc,
-              message: 'Cannot reassign variable',
-            }),
-          );
-          break;
-        }
-      }
-    }
-  }
-}

compiler/packages/babel-plugin-react-compiler/src/__tests__/envConfig-test.ts

@@ -20,7 +20,7 @@ describe('parseConfigPragma()', () => {
         validateHooksUsage: 1,
       } as any);
     }).toThrowErrorMatchingInlineSnapshot(
-      `"Error: Could not validate environment config. Update React Compiler config to fix the error. Validation error: Invalid input: expected boolean, received number at "validateHooksUsage"."`,
+      `"Error: Could not validate environment config. Update React Compiler config to fix the error. Validation error: Expected boolean, received number at "validateHooksUsage"."`,
     );
   });
 
@@ -38,7 +38,7 @@ describe('parseConfigPragma()', () => {
         ],
       } as any);
     }).toThrowErrorMatchingInlineSnapshot(
-      `"Error: Could not validate environment config. Update React Compiler config to fix the error. Validation error: AutodepsIndex must be > 0 at "inferEffectDependencies[0].autodepsIndex"."`,
+      `"Error: Could not validate environment config. Update React Compiler config to fix the error. Validation error: autodepsIndex must be > 0 at "inferEffectDependencies[0].autodepsIndex"."`,
     );
   });
 

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/allocating-primitive-as-dep.expect.md

@@ -2,7 +2,6 @@
 ## Input
 
 ```javascript
-// @enablePreserveExistingMemoizationGuarantees:false
 // bar(props.b) is an allocating expression that produces a primitive, which means
 // that Forget should memoize it.
 // Correctness:
@@ -17,8 +16,7 @@ function AllocatingPrimitiveAsDep(props) {
 ## Code
 
 ```javascript
-import { c as _c } from "react/compiler-runtime"; // @enablePreserveExistingMemoizationGuarantees:false
-// bar(props.b) is an allocating expression that produces a primitive, which means
+import { c as _c } from "react/compiler-runtime"; // bar(props.b) is an allocating expression that produces a primitive, which means
 // that Forget should memoize it.
 // Correctness:
 //   - y depends on either bar(props.b) or bar(props.b) + 1

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/allocating-primitive-as-dep.js

@@ -1,4 +1,3 @@
-// @enablePreserveExistingMemoizationGuarantees:false
 // bar(props.b) is an allocating expression that produces a primitive, which means
 // that Forget should memoize it.
 // Correctness:

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

@@ -2,7 +2,6 @@
 ## Input
 
 ```javascript
-// @enablePreserveExistingMemoizationGuarantees:false
 import {useMemo} from 'react';
 
 const someGlobal = {value: 0};
@@ -33,7 +32,7 @@ export const FIXTURE_ENTRYPOINT = {
 ## Code
 
 ```javascript
-import { c as _c } from "react/compiler-runtime"; // @enablePreserveExistingMemoizationGuarantees:false
+import { c as _c } from "react/compiler-runtime";
 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 +1,3 @@
-// @enablePreserveExistingMemoizationGuarantees:false
 import {useMemo} from 'react';
 
 const someGlobal = {value: 0};

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/computed-load-primitive-as-dependency.expect.md

@@ -2,7 +2,6 @@
 ## Input
 
 ```javascript
-// @enablePreserveExistingMemoizationGuarantees:false
 function Component(props) {
   let a = foo();
   // freeze `a` so we know the next line cannot mutate it
@@ -18,7 +17,7 @@ function Component(props) {
 ## Code
 
 ```javascript
-import { c as _c } from "react/compiler-runtime"; // @enablePreserveExistingMemoizationGuarantees:false
+import { c as _c } from "react/compiler-runtime";
 function Component(props) {
   const $ = _c(2);
   const a = foo();

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/computed-load-primitive-as-dependency.js

@@ -1,4 +1,3 @@
-// @enablePreserveExistingMemoizationGuarantees:false
 function Component(props) {
   let a = foo();
   // freeze `a` so we know the next line cannot mutate it

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/constant-propagation-template-literal.expect.md

@@ -2,7 +2,6 @@
 ## Input
 
 ```javascript
-// @enablePreserveExistingMemoizationGuarantees:false
 import {Stringify, identity} from 'shared-runtime';
 
 function foo() {
@@ -65,7 +64,7 @@ export const FIXTURE_ENTRYPOINT = {
 ## Code
 
 ```javascript
-import { c as _c } from "react/compiler-runtime"; // @enablePreserveExistingMemoizationGuarantees:false
+import { c as _c } from "react/compiler-runtime";
 import { Stringify, identity } from "shared-runtime";
 
 function foo() {

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/constant-propagation-template-literal.js

@@ -1,4 +1,3 @@
-// @enablePreserveExistingMemoizationGuarantees:false
 import {Stringify, identity} from 'shared-runtime';
 
 function foo() {

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

@@ -2,7 +2,6 @@
 ## Input
 
 ```javascript
-// @enablePreserveExistingMemoizationGuarantees:false
 import {useMemo} from 'react';
 import {Stringify} from 'shared-runtime';
 
@@ -26,7 +25,7 @@ export const FIXTURE_ENTRYPOINT = {
 ## Code
 
 ```javascript
-import { c as _c } from "react/compiler-runtime"; // @enablePreserveExistingMemoizationGuarantees:false
+import { c as _c } from "react/compiler-runtime";
 import { useMemo } from "react";
 import { Stringify } from "shared-runtime";
 

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

@@ -1,4 +1,3 @@
-// @enablePreserveExistingMemoizationGuarantees:false
 import {useMemo} from 'react';
 import {Stringify} from 'shared-runtime';
 

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/destructure-direct-reassignment.expect.md

@@ -2,7 +2,6 @@
 ## Input
 
 ```javascript
-// @enablePreserveExistingMemoizationGuarantees:false
 function foo(props) {
   let x, y;
   ({x, y} = {x: props.a, y: props.b});
@@ -22,7 +21,6 @@ export const FIXTURE_ENTRYPOINT = {
 ## Code
 
 ```javascript
-// @enablePreserveExistingMemoizationGuarantees:false
 function foo(props) {
   let x;
   let y;

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/destructure-direct-reassignment.js

@@ -1,4 +1,3 @@
-// @enablePreserveExistingMemoizationGuarantees:false
 function foo(props) {
   let x, y;
   ({x, y} = {x: props.a, y: props.b});

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-reassign-variable-in-usememo.expect.md

@@ -1,38 +0,0 @@
-
-## Input
-
-```javascript
-function Component() {
-  let x;
-  const y = useMemo(() => {
-    let z;
-    x = [];
-    z = true;
-    return z;
-  }, []);
-  return [x, y];
-}
-
-```
-
-
-## Error
-
-```
-Found 1 error:
-
-Error: useMemo() callbacks may not reassign variables declared outside of the callback
-
-useMemo() callbacks must be pure functions and cannot reassign variables defined outside of the callback function.
-
-error.invalid-reassign-variable-in-usememo.ts:5:4
-  3 |   const y = useMemo(() => {
-  4 |     let z;
-> 5 |     x = [];
-    |     ^ Cannot reassign variable
-  6 |     z = true;
-  7 |     return z;
-  8 |   }, []);
-```
-          
-      

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-reassign-variable-in-usememo.js

@@ -1,10 +0,0 @@
-function Component() {
-  let x;
-  const y = useMemo(() => {
-    let z;
-    x = [];
-    z = true;
-    return z;
-  }, []);
-  return [x, y];
-}

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-setState-in-render-unbound-state.expect.md

@@ -1,41 +0,0 @@
-
-## Input
-
-```javascript
-function Component(props) {
-  // Intentionally don't bind state, this repros a bug where we didn't
-  // infer the type of destructured properties after a hole in the array
-  let [, setState] = useState();
-  setState(1);
-  return props.foo;
-}
-
-export const FIXTURE_ENTRYPOINT = {
-  fn: Component,
-  params: ['TodoAdd'],
-  isComponent: 'TodoAdd',
-};
-
-```
-
-
-## Error
-
-```
-Found 1 error:
-
-Error: Calling setState during render may trigger an infinite loop
-
-Calling setState during render will trigger another render, and can lead to infinite loops. (https://react.dev/reference/react/useState).
-
-error.invalid-setState-in-render-unbound-state.ts:5:2
-  3 |   // infer the type of destructured properties after a hole in the array
-  4 |   let [, setState] = useState();
-> 5 |   setState(1);
-    |   ^^^^^^^^ Found setState() in render
-  6 |   return props.foo;
-  7 | }
-  8 |
-```
-          
-      

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-setState-in-render-unbound-state.js

@@ -1,13 +0,0 @@
-function Component(props) {
-  // Intentionally don't bind state, this repros a bug where we didn't
-  // infer the type of destructured properties after a hole in the array
-  let [, setState] = useState();
-  setState(1);
-  return props.foo;
-}
-
-export const FIXTURE_ENTRYPOINT = {
-  fn: Component,
-  params: ['TodoAdd'],
-  isComponent: 'TodoAdd',
-};

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-uncalled-function-capturing-mutable-values-memoizes-with-captures-values.expect.md

@@ -2,7 +2,7 @@
 ## Input
 
 ```javascript
-// @flow @enableNewMutationAliasingModel @enablePreserveExistingMemoizationGuarantees:false
+// @flow @enableNewMutationAliasingModel
 /**
  * This hook returns a function that when called with an input object,
  * will return the result of mapping that input with the supplied map

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-uncalled-function-capturing-mutable-values-memoizes-with-captures-values.js

@@ -1,4 +1,4 @@
-// @flow @enableNewMutationAliasingModel @enablePreserveExistingMemoizationGuarantees:false
+// @flow @enableNewMutationAliasingModel
 /**
  * This hook returns a function that when called with an input object,
  * will return the result of mapping that input with the supplied map

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-unused-usememo.expect.md

@@ -1,35 +0,0 @@
-
-## Input
-
-```javascript
-// @validateNoVoidUseMemo
-function Component() {
-  useMemo(() => {
-    return [];
-  }, []);
-  return <div />;
-}
-
-```
-
-
-## Error
-
-```
-Found 1 error:
-
-Error: Unused useMemo()
-
-This useMemo() value is unused. useMemo() is for computing and caching values, not for arbitrary side effects.
-
-error.invalid-unused-usememo.ts:3:2
-  1 | // @validateNoVoidUseMemo
-  2 | function Component() {
-> 3 |   useMemo(() => {
-    |   ^^^^^^^ useMemo() result is unused
-  4 |     return [];
-  5 |   }, []);
-  6 |   return <div />;
-```
-          
-      

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-unused-usememo.js

@@ -1,7 +0,0 @@
-// @validateNoVoidUseMemo
-function Component() {
-  useMemo(() => {
-    return [];
-  }, []);
-  return <div />;
-}

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.repro-preserve-memoization-inner-destructured-value-mistaken-as-dependency-later-mutation.expect.md

@@ -2,7 +2,7 @@
 ## Input
 
 ```javascript
-// @validatePreserveExistingMemoizationGuarantees @enablePreserveExistingMemoizationGuarantees:false
+// @validatePreserveExistingMemoizationGuarantees
 
 /**
  * Repro from https://github.com/facebook/react/issues/34262

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.repro-preserve-memoization-inner-destructured-value-mistaken-as-dependency-later-mutation.js

@@ -1,4 +1,4 @@
-// @validatePreserveExistingMemoizationGuarantees @enablePreserveExistingMemoizationGuarantees:false
+// @validatePreserveExistingMemoizationGuarantees
 
 /**
  * Repro from https://github.com/facebook/react/issues/34262

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.repro-preserve-memoization-inner-destructured-value-mistaken-as-dependency-mutated-dep.expect.md

@@ -2,7 +2,7 @@
 ## Input
 
 ```javascript
-// @validatePreserveExistingMemoizationGuarantees @enablePreserveExistingMemoizationGuarantees:false
+// @validatePreserveExistingMemoizationGuarantees
 
 import {identity, Stringify, useHook} from 'shared-runtime';
 

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.repro-preserve-memoization-inner-destructured-value-mistaken-as-dependency-mutated-dep.js

@@ -1,4 +1,4 @@
-// @validatePreserveExistingMemoizationGuarantees @enablePreserveExistingMemoizationGuarantees:false
+// @validatePreserveExistingMemoizationGuarantees
 
 import {identity, Stringify, useHook} from 'shared-runtime';
 

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.todo-repro-missed-memoization-from-capture-in-invoked-function-inferred-as-mutation.expect.md

@@ -2,7 +2,7 @@
 ## Input
 
 ```javascript
-// @flow @validatePreserveExistingMemoizationGuarantees @enablePreserveExistingMemoizationGuarantees:false
+// @flow @validatePreserveExistingMemoizationGuarantees
 import {useMemo} from 'react';
 import {logValue, useFragment, useHook, typedLog} from 'shared-runtime';
 

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.todo-repro-missed-memoization-from-capture-in-invoked-function-inferred-as-mutation.js

@@ -1,4 +1,4 @@
-// @flow @validatePreserveExistingMemoizationGuarantees @enablePreserveExistingMemoizationGuarantees:false
+// @flow @validatePreserveExistingMemoizationGuarantees
 import {useMemo} from 'react';
 import {logValue, useFragment, useHook, typedLog} from 'shared-runtime';
 

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.todo-repro-missed-memoization-from-inferred-mutation-in-logger.expect.md

@@ -2,7 +2,7 @@
 ## Input
 
 ```javascript
-// @flow @validatePreserveExistingMemoizationGuarantees @enablePreserveExistingMemoizationGuarantees:false
+// @flow @validatePreserveExistingMemoizationGuarantees
 import {useFragment} from 'react-relay';
 import LogEvent from 'LogEvent';
 import {useCallback, useMemo} from 'react';

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.todo-repro-missed-memoization-from-inferred-mutation-in-logger.js

@@ -1,4 +1,4 @@
-// @flow @validatePreserveExistingMemoizationGuarantees @enablePreserveExistingMemoizationGuarantees:false
+// @flow @validatePreserveExistingMemoizationGuarantees
 import {useFragment} from 'react-relay';
 import LogEvent from 'LogEvent';
 import {useCallback, useMemo} from 'react';

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.todo-repro-unmemoized-callback-captured-in-context-variable.expect.md

@@ -2,7 +2,7 @@
 ## Input
 
 ```javascript
-// @validatePreserveExistingMemoizationGuarantees @enablePreserveExistingMemoizationGuarantees:false
+// @validatePreserveExistingMemoizationGuarantees
 import {useMemo} from 'react';
 import {ValidateMemoization, useHook} from 'shared-runtime';
 

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.todo-repro-unmemoized-callback-captured-in-context-variable.tsx

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

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.useMemo-no-return-value.expect.md

@@ -28,7 +28,7 @@ Found 2 errors:
 
 Error: useMemo() callbacks must return a value
 
-This useMemo() callback doesn't return a value. useMemo() is for computing and caching values, not for arbitrary side effects.
+This useMemo callback doesn't return a value. useMemo is for computing and caching values, not for arbitrary side effects.
 
 error.useMemo-no-return-value.ts:3:16
   1 | // @validateNoVoidUseMemo
@@ -45,7 +45,7 @@ error.useMemo-no-return-value.ts:3:16
 
 Error: useMemo() callbacks must return a value
 
-This React.useMemo() callback doesn't return a value. useMemo() is for computing and caching values, not for arbitrary side effects.
+This React.useMemo callback doesn't return a value. useMemo is for computing and caching values, not for arbitrary side effects.
 
 error.useMemo-no-return-value.ts:6:17
    4 |     console.log('computing');

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.validate-object-entries-mutation.expect.md

@@ -2,7 +2,7 @@
 ## Input
 
 ```javascript
-// @validatePreserveExistingMemoizationGuarantees @enablePreserveExistingMemoizationGuarantees:false
+// @validatePreserveExistingMemoizationGuarantees
 import {makeObject_Primitives, Stringify} from 'shared-runtime';
 
 function Component(props) {

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.validate-object-entries-mutation.js

@@ -1,4 +1,4 @@
-// @validatePreserveExistingMemoizationGuarantees @enablePreserveExistingMemoizationGuarantees:false
+// @validatePreserveExistingMemoizationGuarantees
 import {makeObject_Primitives, Stringify} from 'shared-runtime';
 
 function Component(props) {

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.validate-object-values-mutation.expect.md

@@ -2,7 +2,7 @@
 ## Input
 
 ```javascript
-// @validatePreserveExistingMemoizationGuarantees @enablePreserveExistingMemoizationGuarantees:false
+// @validatePreserveExistingMemoizationGuarantees
 import {makeObject_Primitives, Stringify} from 'shared-runtime';
 
 function Component(props) {

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.validate-object-values-mutation.js

@@ -1,4 +1,4 @@
-// @validatePreserveExistingMemoizationGuarantees @enablePreserveExistingMemoizationGuarantees:false
+// @validatePreserveExistingMemoizationGuarantees
 import {makeObject_Primitives, Stringify} from 'shared-runtime';
 
 function Component(props) {

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/existing-variables-with-c-name.expect.md

@@ -2,7 +2,6 @@
 ## Input
 
 ```javascript
-// @enablePreserveExistingMemoizationGuarantees:false
 import {useMemo, useState} from 'react';
 import {ValidateMemoization} from 'shared-runtime';
 
@@ -29,7 +28,7 @@ export const FIXTURE_ENTRYPOINT = {
 ## Code
 
 ```javascript
-import { c as _c2 } from "react/compiler-runtime"; // @enablePreserveExistingMemoizationGuarantees:false
+import { c as _c2 } from "react/compiler-runtime";
 import { useMemo, useState } from "react";
 import { ValidateMemoization } from "shared-runtime";
 

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/existing-variables-with-c-name.js

@@ -1,4 +1,3 @@
-// @enablePreserveExistingMemoizationGuarantees:false
 import {useMemo, useState} from 'react';
 import {ValidateMemoization} from 'shared-runtime';
 

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/fbt/bug-fbt-plural-multiple-function-calls.expect.md

@@ -2,7 +2,6 @@
 ## Input
 
 ```javascript
-// @enablePreserveExistingMemoizationGuarantees:false
 import fbt from 'fbt';
 
 /**
@@ -36,7 +35,7 @@ export const FIXTURE_ENTRYPOINT = {
 ## Code
 
 ```javascript
-import { c as _c } from "react/compiler-runtime"; // @enablePreserveExistingMemoizationGuarantees:false
+import { c as _c } from "react/compiler-runtime";
 import fbt from "fbt";
 
 /**

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/fbt/bug-fbt-plural-multiple-function-calls.ts

@@ -1,4 +1,3 @@
-// @enablePreserveExistingMemoizationGuarantees:false
 import fbt from 'fbt';
 
 /**

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/fbt/error.todo-fbt-param-nested-fbt.expect.md

@@ -0,0 +1,56 @@
+
+## Input
+
+```javascript
+import fbt from 'fbt';
+import {Stringify} from 'shared-runtime';
+
+/**
+ * MemoizeFbtAndMacroOperands needs to account for nested fbt calls.
+ * Expected fixture `fbt-param-call-arguments` to succeed but it failed with error:
+ *   /fbt-param-call-arguments.ts: Line 19 Column 11: fbt: unsupported babel node: Identifier
+ *   ---
+ *   t3
+ *   ---
+ */
+function Component({firstname, lastname}) {
+  'use memo';
+  return (
+    <Stringify>
+      {fbt(
+        [
+          'Name: ',
+          fbt.param('firstname', <Stringify key={0} name={firstname} />),
+          ', ',
+          fbt.param(
+            'lastname',
+            <Stringify key={0} name={lastname}>
+              {fbt('(inner fbt)', 'Inner fbt value')}
+            </Stringify>
+          ),
+        ],
+        'Name'
+      )}
+    </Stringify>
+  );
+}
+
+export const FIXTURE_ENTRYPOINT = {
+  fn: Component,
+  params: [{firstname: 'first', lastname: 'last'}],
+  sequentialRenders: [{firstname: 'first', lastname: 'last'}],
+};
+
+```
+
+
+## Error
+
+```
+Line 19 Column 11: fbt: unsupported babel node: Identifier
+---
+t3
+---
+```
+          
+      

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/fbt/fbt-preserve-whitespace-two-subtrees.expect.md

@@ -37,31 +37,27 @@ import { c as _c } from "react/compiler-runtime";
 import fbt from "fbt";
 
 function Foo(t0) {
-  const $ = _c(7);
+  const $ = _c(3);
   const { name1, name2 } = t0;
   let t1;
   if ($[0] !== name1 || $[1] !== name2) {
-    let t2;
-    if ($[3] !== name1) {
-      t2 = <b>{name1}</b>;
-      $[3] = name1;
-      $[4] = t2;
-    } else {
-      t2 = $[4];
-    }
-    let t3;
-    if ($[5] !== name2) {
-      t3 = <b>{name2}</b>;
-      $[5] = name2;
-      $[6] = t3;
-    } else {
-      t3 = $[6];
-    }
     t1 = fbt._(
       "{user1} and {user2} accepted your PR!",
       [
-        fbt._param("user1", <span key={name1}>{t2}</span>),
-        fbt._param("user2", <span key={name2}>{t3}</span>),
+        fbt._param(
+          "user1",
+
+          <span key={name1}>
+            <b>{name1}</b>
+          </span>,
+        ),
+        fbt._param(
+          "user2",
+
+          <span key={name2}>
+            <b>{name2}</b>
+          </span>,
+        ),
       ],
       { hk: "2PxMie" },
     );

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/fbt/repro-fbt-param-nested-fbt.expect.md

@@ -1,111 +0,0 @@
-
-## Input
-
-```javascript
-import fbt from 'fbt';
-import {Stringify} from 'shared-runtime';
-
-/**
- * MemoizeFbtAndMacroOperands needs to account for nested fbt calls.
- * Expected fixture `fbt-param-call-arguments` to succeed but it failed with error:
- *   /fbt-param-call-arguments.ts: Line 19 Column 11: fbt: unsupported babel node: Identifier
- *   ---
- *   t3
- *   ---
- */
-function Component({firstname, lastname}) {
-  'use memo';
-  return (
-    <Stringify>
-      {fbt(
-        [
-          'Name: ',
-          fbt.param('firstname', <Stringify key={0} name={firstname} />),
-          ', ',
-          fbt.param(
-            'lastname',
-            <Stringify key={0} name={lastname}>
-              {fbt('(inner fbt)', 'Inner fbt value')}
-            </Stringify>
-          ),
-        ],
-        'Name'
-      )}
-    </Stringify>
-  );
-}
-
-export const FIXTURE_ENTRYPOINT = {
-  fn: Component,
-  params: [{firstname: 'first', lastname: 'last'}],
-  sequentialRenders: [{firstname: 'first', lastname: 'last'}],
-};
-
-```
-
-## Code
-
-```javascript
-import { c as _c } from "react/compiler-runtime";
-import fbt from "fbt";
-import { Stringify } from "shared-runtime";
-
-/**
- * MemoizeFbtAndMacroOperands needs to account for nested fbt calls.
- * Expected fixture `fbt-param-call-arguments` to succeed but it failed with error:
- *   /fbt-param-call-arguments.ts: Line 19 Column 11: fbt: unsupported babel node: Identifier
- *   ---
- *   t3
- *   ---
- */
-function Component(t0) {
-  "use memo";
-  const $ = _c(5);
-  const { firstname, lastname } = t0;
-  let t1;
-  if ($[0] !== firstname || $[1] !== lastname) {
-    t1 = fbt._(
-      "Name: {firstname}, {lastname}",
-      [
-        fbt._param(
-          "firstname",
-
-          <Stringify key={0} name={firstname} />,
-        ),
-        fbt._param(
-          "lastname",
-
-          <Stringify key={0} name={lastname}>
-            {fbt._("(inner fbt)", null, { hk: "36qNwF" })}
-          </Stringify>,
-        ),
-      ],
-      { hk: "3AiIf8" },
-    );
-    $[0] = firstname;
-    $[1] = lastname;
-    $[2] = t1;
-  } else {
-    t1 = $[2];
-  }
-  let t2;
-  if ($[3] !== t1) {
-    t2 = <Stringify>{t1}</Stringify>;
-    $[3] = t1;
-    $[4] = t2;
-  } else {
-    t2 = $[4];
-  }
-  return t2;
-}
-
-export const FIXTURE_ENTRYPOINT = {
-  fn: Component,
-  params: [{ firstname: "first", lastname: "last" }],
-  sequentialRenders: [{ firstname: "first", lastname: "last" }],
-};
-
-```
-      
-### Eval output
-(kind: ok) <div>{"children":"Name: , "}</div>

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/fbt/repro-separately-memoized-fbt-param.expect.md

@@ -1,78 +0,0 @@
-
-## Input
-
-```javascript
-import {fbt} from 'fbt';
-import {useState} from 'react';
-
-const MIN = 10;
-
-function Component() {
-  const [count, setCount] = useState(0);
-
-  return fbt(
-    'Expected at least ' +
-      fbt.param('min', MIN, {number: true}) +
-      ' items, but got ' +
-      fbt.param('count', count, {number: true}) +
-      ' items.',
-    'Error description'
-  );
-}
-
-export const FIXTURE_ENTRYPOINT = {
-  fn: Component,
-  params: [{}],
-};
-
-```
-
-## Code
-
-```javascript
-import { c as _c } from "react/compiler-runtime";
-import { fbt } from "fbt";
-import { useState } from "react";
-
-const MIN = 10;
-
-function Component() {
-  const $ = _c(2);
-  const [count] = useState(0);
-  let t0;
-  if ($[0] !== count) {
-    t0 = fbt._(
-      { "*": { "*": "Expected at least {min} items, but got {count} items." } },
-      [
-        fbt._param(
-          "min",
-
-          MIN,
-          [0],
-        ),
-        fbt._param(
-          "count",
-
-          count,
-          [0],
-        ),
-      ],
-      { hk: "36gbz8" },
-    );
-    $[0] = count;
-    $[1] = t0;
-  } else {
-    t0 = $[1];
-  }
-  return t0;
-}
-
-export const FIXTURE_ENTRYPOINT = {
-  fn: Component,
-  params: [{}],
-};
-
-```
-      
-### Eval output
-(kind: ok) Expected at least 10 items, but got 0 items.

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/fbt/repro-separately-memoized-fbt-param.js

@@ -1,22 +0,0 @@
-import {fbt} from 'fbt';
-import {useState} from 'react';
-
-const MIN = 10;
-
-function Component() {
-  const [count, setCount] = useState(0);
-
-  return fbt(
-    'Expected at least ' +
-      fbt.param('min', MIN, {number: true}) +
-      ' items, but got ' +
-      fbt.param('count', count, {number: true}) +
-      ' items.',
-    'Error description'
-  );
-}
-
-export const FIXTURE_ENTRYPOINT = {
-  fn: Component,
-  params: [{}],
-};

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/for-in-statement-type-inference.expect.md

@@ -2,7 +2,6 @@
 ## Input
 
 ```javascript
-// @enablePreserveExistingMemoizationGuarantees:false
 const {identity, mutate} = require('shared-runtime');
 
 function Component(props) {
@@ -25,7 +24,6 @@ export const FIXTURE_ENTRYPOINT = {
 ## Code
 
 ```javascript
-// @enablePreserveExistingMemoizationGuarantees:false
 const { identity, mutate } = require("shared-runtime");
 
 function Component(props) {

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/for-in-statement-type-inference.js

@@ -1,4 +1,3 @@
-// @enablePreserveExistingMemoizationGuarantees:false
 const {identity, mutate} = require('shared-runtime');
 
 function Component(props) {

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

@@ -0,0 +1,35 @@
+
+## Input
+
+```javascript
+function t(props) {
+  let [, setstate] = useState();
+  setstate(1);
+  return props.foo;
+}
+
+export const FIXTURE_ENTRYPOINT = {
+  fn: t,
+  params: ['TodoAdd'],
+  isComponent: 'TodoAdd',
+};
+
+```
+
+## Code
+
+```javascript
+function t(props) {
+  const [, setstate] = useState();
+  setstate(1);
+  return props.foo;
+}
+
+export const FIXTURE_ENTRYPOINT = {
+  fn: t,
+  params: ["TodoAdd"],
+  isComponent: "TodoAdd",
+};
+
+```
+      

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/holey-array.js

@@ -0,0 +1,11 @@
+function t(props) {
+  let [, setstate] = useState();
+  setstate(1);
+  return props.foo;
+}
+
+export const FIXTURE_ENTRYPOINT = {
+  fn: t,
+  params: ['TodoAdd'],
+  isComponent: 'TodoAdd',
+};

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/hooks-with-prefix.expect.md

@@ -2,7 +2,7 @@
 ## Input
 
 ```javascript
-// @hookPattern:".*\b(use[^$]+)$" @enablePreserveExistingMemoizationGuarantees:false
+// @hookPattern:".*\b(use[^$]+)$"
 
 import * as React from 'react';
 import {makeArray, useHook} from 'shared-runtime';
@@ -36,7 +36,7 @@ export const FIXTURE_ENTRYPOINT = {
 ## Code
 
 ```javascript
-import { c as _c } from "react/compiler-runtime"; // @hookPattern:".*\b(use[^$]+)$" @enablePreserveExistingMemoizationGuarantees:false
+import { c as _c } from "react/compiler-runtime"; // @hookPattern:".*\b(use[^$]+)$"
 
 import * as React from "react";
 import { makeArray, useHook } from "shared-runtime";

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/hooks-with-prefix.js

@@ -1,4 +1,4 @@
-// @hookPattern:".*\b(use[^$]+)$" @enablePreserveExistingMemoizationGuarantees:false
+// @hookPattern:".*\b(use[^$]+)$"
 
 import * as React from 'react';
 import {makeArray, useHook} from 'shared-runtime';

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/idx-method-no-outlining-wildcard.expect.md

@@ -73,7 +73,7 @@ function Component(props) {
   const groupName4 = t3;
   let t4;
   if ($[8] !== props) {
-    t4 = idx.hello_world.b.c(props, (__3) => __3.group.label);
+    t4 = idx.hello_world.b.c(props, _temp3);
     $[8] = props;
     $[9] = t4;
   } else {
@@ -108,6 +108,9 @@ function Component(props) {
   }
   return t5;
 }
+function _temp3(__3) {
+  return __3.group.label;
+}
 function _temp2(__0) {
   return __0.group.label;
 }

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/idx-method-no-outlining.expect.md

@@ -49,7 +49,7 @@ function Component(props) {
   const groupName2 = t1;
   let t2;
   if ($[4] !== props) {
-    t2 = idx.a.b(props, (__1) => __1.group.label);
+    t2 = idx.a.b(props, _temp2);
     $[4] = props;
     $[5] = t2;
   } else {
@@ -74,6 +74,9 @@ function Component(props) {
   }
   return t3;
 }
+function _temp2(__1) {
+  return __1.group.label;
+}
 function _temp(_) {
   return _.group.label;
 }

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/infer-computed-delete.expect.md

@@ -2,7 +2,7 @@
 ## Input
 
 ```javascript
-// @debug @enablePreserveExistingMemoizationGuarantees:false
+// @debug
 function Component(props) {
   const x = makeObject();
   const y = delete x[props.value];
@@ -14,7 +14,7 @@ function Component(props) {
 ## Code
 
 ```javascript
-// @debug @enablePreserveExistingMemoizationGuarantees:false
+// @debug
 function Component(props) {
   const x = makeObject();
   const y = delete x[props.value];

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/infer-computed-delete.js

@@ -1,4 +1,4 @@
-// @debug @enablePreserveExistingMemoizationGuarantees:false
+// @debug
 function Component(props) {
   const x = makeObject();
   const y = delete x[props.value];

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/infer-property-delete.expect.md

@@ -2,7 +2,6 @@
 ## Input
 
 ```javascript
-// @enablePreserveExistingMemoizationGuarantees:false
 function Component(props) {
   const x = makeObject();
   const y = delete x.value;
@@ -14,7 +13,6 @@ function Component(props) {
 ## Code
 
 ```javascript
-// @enablePreserveExistingMemoizationGuarantees:false
 function Component(props) {
   const x = makeObject();
   const y = delete x.value;

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/infer-property-delete.js

@@ -1,4 +1,3 @@
-// @enablePreserveExistingMemoizationGuarantees:false
 function Component(props) {
   const x = makeObject();
   const y = delete x.value;

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/new-mutability/error.invalid-useCallback-captures-reassigned-context.expect.md

@@ -2,7 +2,7 @@
 ## Input
 
 ```javascript
-// @validatePreserveExistingMemoizationGuarantees @enableNewMutationAliasingModel @enablePreserveExistingMemoizationGuarantees:false
+// @validatePreserveExistingMemoizationGuarantees @enableNewMutationAliasingModel
 import {useCallback} from 'react';
 import {makeArray} from 'shared-runtime';
 

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/new-mutability/error.invalid-useCallback-captures-reassigned-context.js

@@ -1,4 +1,4 @@
-// @validatePreserveExistingMemoizationGuarantees @enableNewMutationAliasingModel @enablePreserveExistingMemoizationGuarantees:false
+// @validatePreserveExistingMemoizationGuarantees @enableNewMutationAliasingModel
 import {useCallback} from 'react';
 import {makeArray} from 'shared-runtime';
 

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/new-mutability/mutate-through-identity-function-expression.expect.md

@@ -2,7 +2,6 @@
 ## Input
 
 ```javascript
-// @enablePreserveExistingMemoizationGuarantees:false
 import {useMemo} from 'react';
 import {identity, ValidateMemoization} from 'shared-runtime';
 
@@ -33,7 +32,7 @@ export const FIXTURE_ENTRYPOINT = {
 ## Code
 
 ```javascript
-import { c as _c } from "react/compiler-runtime"; // @enablePreserveExistingMemoizationGuarantees:false
+import { c as _c } from "react/compiler-runtime";
 import { useMemo } from "react";
 import { identity, ValidateMemoization } from "shared-runtime";
 

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/new-mutability/mutate-through-identity-function-expression.js

@@ -1,4 +1,3 @@
-// @enablePreserveExistingMemoizationGuarantees:false
 import {useMemo} from 'react';
 import {identity, ValidateMemoization} from 'shared-runtime';
 

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/new-mutability/mutate-through-identity.expect.md

@@ -2,7 +2,6 @@
 ## Input
 
 ```javascript
-// @enablePreserveExistingMemoizationGuarantees:false
 import {useMemo} from 'react';
 import {identity, ValidateMemoization} from 'shared-runtime';
 
@@ -30,7 +29,7 @@ export const FIXTURE_ENTRYPOINT = {
 ## Code
 
 ```javascript
-import { c as _c } from "react/compiler-runtime"; // @enablePreserveExistingMemoizationGuarantees:false
+import { c as _c } from "react/compiler-runtime";
 import { useMemo } from "react";
 import { identity, ValidateMemoization } from "shared-runtime";
 

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/new-mutability/mutate-through-identity.js

@@ -1,4 +1,3 @@
-// @enablePreserveExistingMemoizationGuarantees:false
 import {useMemo} from 'react';
 import {identity, ValidateMemoization} from 'shared-runtime';
 

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/new-mutability/todo-control-flow-sensitive-mutation.expect.md

@@ -2,7 +2,6 @@
 ## Input
 
 ```javascript
-// @enablePreserveExistingMemoizationGuarantees:false
 import {useMemo} from 'react';
 import {
   mutate,
@@ -50,7 +49,7 @@ export const FIXTURE_ENTRYPOINT = {
 ## Code
 
 ```javascript
-import { c as _c } from "react/compiler-runtime"; // @enablePreserveExistingMemoizationGuarantees:false
+import { c as _c } from "react/compiler-runtime";
 import { useMemo } from "react";
 import {
   mutate,

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/new-mutability/todo-control-flow-sensitive-mutation.tsx

@@ -1,4 +1,3 @@
-// @enablePreserveExistingMemoizationGuarantees:false
 import {useMemo} from 'react';
 import {
   mutate,

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/new-mutability/todo-transitivity-createfrom-capture-lambda.expect.md

@@ -2,7 +2,6 @@
 ## Input
 
 ```javascript
-// @enablePreserveExistingMemoizationGuarantees:false
 import {useMemo} from 'react';
 import {
   typedCapture,
@@ -42,7 +41,7 @@ export const FIXTURE_ENTRYPOINT = {
 ## Code
 
 ```javascript
-import { c as _c } from "react/compiler-runtime"; // @enablePreserveExistingMemoizationGuarantees:false
+import { c as _c } from "react/compiler-runtime";
 import { useMemo } from "react";
 import {
   typedCapture,

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/new-mutability/todo-transitivity-createfrom-capture-lambda.tsx

@@ -1,4 +1,3 @@
-// @enablePreserveExistingMemoizationGuarantees:false
 import {useMemo} from 'react';
 import {
   typedCapture,

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/new-mutability/transitivity-add-captured-array-to-itself.expect.md

@@ -2,7 +2,6 @@
 ## Input
 
 ```javascript
-// @enablePreserveExistingMemoizationGuarantees:false
 import {useMemo} from 'react';
 import {
   typedCapture,
@@ -43,7 +42,7 @@ export const FIXTURE_ENTRYPOINT = {
 ## Code
 
 ```javascript
-import { c as _c } from "react/compiler-runtime"; // @enablePreserveExistingMemoizationGuarantees:false
+import { c as _c } from "react/compiler-runtime";
 import { useMemo } from "react";
 import {
   typedCapture,

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/new-mutability/transitivity-add-captured-array-to-itself.tsx

@@ -1,4 +1,3 @@
-// @enablePreserveExistingMemoizationGuarantees:false
 import {useMemo} from 'react';
 import {
   typedCapture,

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/new-mutability/transitivity-capture-createfrom-lambda.expect.md

@@ -2,7 +2,6 @@
 ## Input
 
 ```javascript
-// @enablePreserveExistingMemoizationGuarantees:false
 import {useMemo} from 'react';
 import {
   typedCapture,
@@ -41,7 +40,7 @@ export const FIXTURE_ENTRYPOINT = {
 ## Code
 
 ```javascript
-import { c as _c } from "react/compiler-runtime"; // @enablePreserveExistingMemoizationGuarantees:false
+import { c as _c } from "react/compiler-runtime";
 import { useMemo } from "react";
 import {
   typedCapture,

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/new-mutability/transitivity-capture-createfrom-lambda.tsx

@@ -1,4 +1,3 @@
-// @enablePreserveExistingMemoizationGuarantees:false
 import {useMemo} from 'react';
 import {
   typedCapture,

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/new-mutability/transitivity-capture-createfrom.expect.md

@@ -2,7 +2,6 @@
 ## Input
 
 ```javascript
-// @enablePreserveExistingMemoizationGuarantees:false
 import {useMemo} from 'react';
 import {
   typedCapture,
@@ -37,7 +36,7 @@ export const FIXTURE_ENTRYPOINT = {
 ## Code
 
 ```javascript
-import { c as _c } from "react/compiler-runtime"; // @enablePreserveExistingMemoizationGuarantees:false
+import { c as _c } from "react/compiler-runtime";
 import { useMemo } from "react";
 import {
   typedCapture,

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/new-mutability/transitivity-capture-createfrom.tsx

@@ -1,4 +1,3 @@
-// @enablePreserveExistingMemoizationGuarantees:false
 import {useMemo} from 'react';
 import {
   typedCapture,

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/new-mutability/transitivity-phi-assign-or-capture.expect.md

@@ -2,7 +2,6 @@
 ## Input
 
 ```javascript
-// @enablePreserveExistingMemoizationGuarantees:false
 import {useMemo} from 'react';
 import {
   typedCapture,
@@ -41,7 +40,7 @@ export const FIXTURE_ENTRYPOINT = {
 ## Code
 
 ```javascript
-import { c as _c } from "react/compiler-runtime"; // @enablePreserveExistingMemoizationGuarantees:false
+import { c as _c } from "react/compiler-runtime";
 import { useMemo } from "react";
 import {
   typedCapture,