[pull] main from facebook:main

.eslintignore

@@ -28,3 +28,6 @@ packages/react-devtools-shared/src/hooks/__tests__/__source__/__untransformed__/
 packages/react-devtools-shell/dist
 packages/react-devtools-timeline/dist
 packages/react-devtools-timeline/static
+
+# Imported third-party Flow types
+flow-typed/

.eslintrc.js

@@ -581,6 +581,7 @@ module.exports = {
     IteratorResult: 'readonly',
     JSONValue: 'readonly',
     JSResourceReference: 'readonly',
+    mixin$Animatable: 'readonly',
     MouseEventHandler: 'readonly',
     NavigateEvent: 'readonly',
     PropagationPhases: 'readonly',
@@ -619,7 +620,6 @@ module.exports = {
     PropertyIndexedKeyframes: 'readonly',
     KeyframeAnimationOptions: 'readonly',
     GetAnimationsOptions: 'readonly',
-    Animatable: 'readonly',
     ScrollTimeline: 'readonly',
     EventListenerOptionsOrUseCapture: 'readonly',
     FocusOptions: 'readonly',

compiler/package.json

@@ -19,7 +19,8 @@
     "test": "yarn workspaces run test",
     "snap": "yarn workspace babel-plugin-react-compiler run snap",
     "snap:build": "yarn workspace snap run build",
-    "npm:publish": "node scripts/release/publish"
+    "npm:publish": "node scripts/release/publish",
+    "eslint-docs": "yarn workspace babel-plugin-react-compiler build && node scripts/build-eslint-docs.js"
   },
   "dependencies": {
     "fs-extra": "^4.0.2",

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

@@ -7,9 +7,10 @@
 
 import * as t from '@babel/types';
 import {codeFrameColumns} from '@babel/code-frame';
-import type {SourceLocation} from './HIR';
+import {type SourceLocation} from './HIR';
 import {Err, Ok, Result} from './Utils/Result';
 import {assertExhaustive} from './Utils/utils';
+import invariant from 'invariant';
 
 export enum ErrorSeverity {
   /**
@@ -628,15 +629,26 @@ export type LintRule = {
   recommended: boolean;
 };
 
+const RULE_NAME_PATTERN = /^[a-z]+(-[a-z]+)*$/;
+
 export function getRuleForCategory(category: ErrorCategory): LintRule {
+  const rule = getRuleForCategoryImpl(category);
+  invariant(
+    RULE_NAME_PATTERN.test(rule.name),
+    `Invalid rule name, got '${rule.name}' but rules must match ${RULE_NAME_PATTERN.toString()}`,
+  );
+  return rule;
+}
+
+function getRuleForCategoryImpl(category: ErrorCategory): LintRule {
   switch (category) {
     case ErrorCategory.AutomaticEffectDependencies: {
       return {
         category,
         name: 'automatic-effect-dependencies',
         description:
           'Verifies that automatic effect dependencies are compiled if opted-in',
-        recommended: true,
+        recommended: false,
       };
     }
     case ErrorCategory.CapitalizedCalls: {
@@ -652,7 +664,7 @@ export function getRuleForCategory(category: ErrorCategory): LintRule {
       return {
         category,
         name: 'config',
-        description: 'Validates the configuration',
+        description: 'Validates the compiler configuration options',
         recommended: true,
       };
     }
@@ -678,7 +690,7 @@ export function getRuleForCategory(category: ErrorCategory): LintRule {
         category,
         name: 'set-state-in-effect',
         description:
-          'Validates against calling setState synchronously in an effect',
+          'Validates against calling setState synchronously in an effect, which can lead to re-renders that degrade performance',
         recommended: true,
       };
     }
@@ -687,7 +699,7 @@ export function getRuleForCategory(category: ErrorCategory): LintRule {
         category,
         name: 'error-boundaries',
         description:
-          'Validates usage of error boundaries instead of try/catch for errors in JSX',
+          'Validates usage of error boundaries instead of try/catch for errors in child components',
         recommended: true,
       };
     }
@@ -711,7 +723,8 @@ export function getRuleForCategory(category: ErrorCategory): LintRule {
       return {
         category,
         name: 'gating',
-        description: 'Validates configuration of gating mode',
+        description:
+          'Validates configuration of [gating mode](https://react.dev/reference/react-compiler/gating)',
         recommended: true,
       };
     }
@@ -720,7 +733,8 @@ export function getRuleForCategory(category: ErrorCategory): LintRule {
         category,
         name: 'globals',
         description:
-          'Validates against assignment/mutation of globals during render',
+          '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)',
         recommended: true,
       };
     }
@@ -742,7 +756,7 @@ export function getRuleForCategory(category: ErrorCategory): LintRule {
         category,
         name: 'immutability',
         description:
-          'Validates that immutable values (props, state, etc) are not mutated',
+          '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)',
         recommended: true,
       };
     }
@@ -759,7 +773,9 @@ export function getRuleForCategory(category: ErrorCategory): LintRule {
         category,
         name: 'preserve-manual-memoization',
         description:
-          'Validates that existing manual memoized is preserved by the compiler',
+          '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)',
         recommended: true,
       };
     }
@@ -768,7 +784,7 @@ export function getRuleForCategory(category: ErrorCategory): LintRule {
         category,
         name: 'purity',
         description:
-          'Validates that the component/hook is pure, and does not call known-impure functions',
+          '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',
         recommended: true,
       };
     }
@@ -777,15 +793,16 @@ export function getRuleForCategory(category: ErrorCategory): LintRule {
         category,
         name: 'refs',
         description:
-          'Validates correct usage of refs, not reading/writing during render',
+          'Validates correct usage of refs, not reading/writing during render. See the "pitfalls" section in [`useRef()` usage](https://react.dev/reference/react/useRef#usage)',
         recommended: true,
       };
     }
     case ErrorCategory.RenderSetState: {
       return {
         category,
         name: 'set-state-in-render',
-        description: 'Validates against setting state during render',
+        description:
+          'Validates against setting state during render, which can trigger additional renders and potential infinite render loops',
         recommended: true,
       };
     }
@@ -794,7 +811,7 @@ export function getRuleForCategory(category: ErrorCategory): LintRule {
         category,
         name: 'static-components',
         description:
-          'Validates that components are static, not recreated every render',
+          'Validates that components are static, not recreated every render. Components that are recreated dynamically can reset state and trigger excessive re-rendering',
         recommended: true,
       };
     }
@@ -826,15 +843,17 @@ export function getRuleForCategory(category: ErrorCategory): LintRule {
       return {
         category,
         name: 'unsupported-syntax',
-        description: 'Validates against syntax that we do not plan to support',
+        description:
+          'Validates against syntax that we do not plan to support in React Compiler',
         recommended: true,
       };
     }
     case ErrorCategory.UseMemo: {
       return {
         category,
         name: 'use-memo',
-        description: 'Validates usage of the useMemo() hook',
+        description:
+          'Validates usage of the useMemo() hook against common mistakes. See [`useMemo()` docs](https://react.dev/reference/react/useMemo) for more information.',
         recommended: true,
       };
     }

compiler/scripts/build-eslint-docs.js

@@ -0,0 +1,32 @@
+const ReactCompiler = require('../packages/babel-plugin-react-compiler/dist');
+
+const combinedRules = [
+  {
+    name: 'rules-of-hooks',
+    recommended: true,
+    description:
+      'Validates that components and hooks follow the [Rules of Hooks](https://react.dev/reference/rules/rules-of-hooks)',
+  },
+  {
+    name: 'exhaustive-deps',
+    recommended: true,
+    description:
+      'Validates that hooks which accept dependency arrays (`useMemo()`, `useCallback()`, `useEffect()`, etc) ' +
+      'list all referenced variables in their dependency array. Referencing a value without including it in the ' +
+      'dependency array can lead to stale UI or callbacks.',
+  },
+  ...ReactCompiler.LintRules,
+];
+
+const printed = combinedRules
+  .filter(rule => rule.recommended)
+  .map(rule => {
+    return `
+## \`react-hooks/${rule.name}\`
+
+${rule.description}
+    `.trim();
+  })
+  .join('\n\n');
+
+console.log(printed);

flow-typed.config.json

@@ -0,0 +1,20 @@
+{
+  "env": [
+    "bom",
+    "cssom",
+    "dom",
+    "geometry",
+    "html",
+    "node",
+    "serviceworkers",
+    "streams",
+    "web-animations"
+  ],
+  "ignore": [
+    "create-react-class",
+    "jest",
+    "regenerator-runtime",
+    "webpack",
+    "ws"
+  ]
+}