[compiler] Use new diagnostics for core inference errors

Uses the new diagnostic type for errors created during mutation/aliasing inference, such as errors for mutating immutable values like props or state, reassigning globals, etc.

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

@@ -12,6 +12,7 @@ import {
   pipelineUsesReanimatedPlugin,
 } from '../Entrypoint/Reanimated';
 import validateNoUntransformedReferences from '../Entrypoint/ValidateNoUntransformedReferences';
+import {CompilerError} from '..';
 
 const ENABLE_REACT_COMPILER_TIMINGS =
   process.env['ENABLE_REACT_COMPILER_TIMINGS'] === '1';
@@ -34,51 +35,58 @@ export default function BabelPluginReactCompiler(
        */
       Program: {
         enter(prog, pass): void {
-          const filename = pass.filename ?? 'unknown';
-          if (ENABLE_REACT_COMPILER_TIMINGS === true) {
-            performance.mark(`${filename}:start`, {
-              detail: 'BabelPlugin:Program:start',
-            });
-          }
-          let opts = parsePluginOptions(pass.opts);
-          const isDev =
-            (typeof __DEV__ !== 'undefined' && __DEV__ === true) ||
-            process.env['NODE_ENV'] === 'development';
-          if (
-            opts.enableReanimatedCheck === true &&
-            pipelineUsesReanimatedPlugin(pass.file.opts.plugins)
-          ) {
-            opts = injectReanimatedFlag(opts);
-          }
-          if (
-            opts.environment.enableResetCacheOnSourceFileChanges !== false &&
-            isDev
-          ) {
-            opts = {
-              ...opts,
-              environment: {
-                ...opts.environment,
-                enableResetCacheOnSourceFileChanges: true,
-              },
-            };
-          }
-          const result = compileProgram(prog, {
-            opts,
-            filename: pass.filename ?? null,
-            comments: pass.file.ast.comments ?? [],
-            code: pass.file.code,
-          });
-          validateNoUntransformedReferences(
-            prog,
-            pass.filename ?? null,
-            opts.logger,
-            opts.environment,
-            result,
-          );
-          if (ENABLE_REACT_COMPILER_TIMINGS === true) {
-            performance.mark(`${filename}:end`, {
-              detail: 'BabelPlugin:Program:end',
+          try {
+            const filename = pass.filename ?? 'unknown';
+            if (ENABLE_REACT_COMPILER_TIMINGS === true) {
+              performance.mark(`${filename}:start`, {
+                detail: 'BabelPlugin:Program:start',
+              });
+            }
+            let opts = parsePluginOptions(pass.opts);
+            const isDev =
+              (typeof __DEV__ !== 'undefined' && __DEV__ === true) ||
+              process.env['NODE_ENV'] === 'development';
+            if (
+              opts.enableReanimatedCheck === true &&
+              pipelineUsesReanimatedPlugin(pass.file.opts.plugins)
+            ) {
+              opts = injectReanimatedFlag(opts);
+            }
+            if (
+              opts.environment.enableResetCacheOnSourceFileChanges !== false &&
+              isDev
+            ) {
+              opts = {
+                ...opts,
+                environment: {
+                  ...opts.environment,
+                  enableResetCacheOnSourceFileChanges: true,
+                },
+              };
+            }
+            const result = compileProgram(prog, {
+              opts,
+              filename: pass.filename ?? null,
+              comments: pass.file.ast.comments ?? [],
+              code: pass.file.code,
             });
+            validateNoUntransformedReferences(
+              prog,
+              pass.filename ?? null,
+              opts.logger,
+              opts.environment,
+              result,
+            );
+            if (ENABLE_REACT_COMPILER_TIMINGS === true) {
+              performance.mark(`${filename}:end`, {
+                detail: 'BabelPlugin:Program:end',
+              });
+            }
+          } catch (e) {
+            if (e instanceof CompilerError) {
+              throw new Error(e.printErrorMessage(pass.file.code));
+            }
+            throw e;
           }
         },
         exit(_, pass): void {

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

@@ -5,6 +5,7 @@
  * LICENSE file in the root directory of this source tree.
  */
 
+import {codeFrameColumns} from '@babel/code-frame';
 import type {SourceLocation} from './HIR';
 import {Err, Ok, Result} from './Utils/Result';
 import {assertExhaustive} from './Utils/utils';
@@ -44,6 +45,24 @@ export enum ErrorSeverity {
   Invariant = 'Invariant',
 }
 
+export type CompilerDiagnosticOptions = {
+  severity: ErrorSeverity;
+  category: string;
+  description: string;
+  details: Array<CompilerDiagnosticDetail>;
+  suggestions?: Array<CompilerSuggestion> | null | undefined;
+};
+
+export type CompilerDiagnosticDetail =
+  /**
+   * A/the source of the error
+   */
+  {
+    kind: 'error';
+    loc: SourceLocation | null;
+    message: string;
+  };
+
 export enum CompilerSuggestionOperation {
   InsertBefore,
   InsertAfter,
@@ -74,6 +93,105 @@ export type CompilerErrorDetailOptions = {
   suggestions?: Array<CompilerSuggestion> | null | undefined;
 };
 
+export class CompilerDiagnostic {
+  options: CompilerDiagnosticOptions;
+
+  constructor(options: CompilerDiagnosticOptions) {
+    this.options = options;
+  }
+
+  static create(
+    options: Omit<CompilerDiagnosticOptions, 'details'>,
+  ): CompilerDiagnostic {
+    return new CompilerDiagnostic({...options, details: []});
+  }
+
+  get category(): CompilerDiagnosticOptions['category'] {
+    return this.options.category;
+  }
+  get description(): CompilerDiagnosticOptions['description'] {
+    return this.options.description;
+  }
+  get severity(): CompilerDiagnosticOptions['severity'] {
+    return this.options.severity;
+  }
+  get suggestions(): CompilerDiagnosticOptions['suggestions'] {
+    return this.options.suggestions;
+  }
+
+  withDetail(detail: CompilerDiagnosticDetail): CompilerDiagnostic {
+    this.options.details.push(detail);
+    return this;
+  }
+
+  primaryLocation(): SourceLocation | null {
+    return this.options.details.filter(d => d.kind === 'error')[0]?.loc ?? null;
+  }
+
+  printErrorMessage(source: string): string {
+    const buffer = [
+      printErrorSummary(this.severity, this.category),
+      '\n\n',
+      this.description,
+    ];
+    for (const detail of this.options.details) {
+      switch (detail.kind) {
+        case 'error': {
+          const loc = detail.loc;
+          if (loc == null || typeof loc === 'symbol') {
+            continue;
+          }
+          let codeFrame: string;
+          try {
+            codeFrame = codeFrameColumns(
+              source,
+              {
+                start: {
+                  line: loc.start.line,
+                  column: loc.start.column + 1,
+                },
+                end: {
+                  line: loc.end.line,
+                  column: loc.end.column + 1,
+                },
+              },
+              {
+                message: detail.message,
+              },
+            );
+          } catch (e) {
+            codeFrame = detail.message;
+          }
+          buffer.push(
+            `\n\n${loc.filename}:${loc.start.line}:${loc.start.column}\n`,
+          );
+          buffer.push(codeFrame);
+          break;
+        }
+        default: {
+          assertExhaustive(
+            detail.kind,
+            `Unexpected detail kind ${(detail as any).kind}`,
+          );
+        }
+      }
+    }
+    return buffer.join('');
+  }
+
+  toString(): string {
+    const buffer = [printErrorSummary(this.severity, this.category)];
+    if (this.description != null) {
+      buffer.push(`. ${this.description}.`);
+    }
+    const loc = this.primaryLocation();
+    if (loc != null && typeof loc !== 'symbol') {
+      buffer.push(` (${loc.start.line}:${loc.start.column})`);
+    }
+    return buffer.join('');
+  }
+}
+
 /*
  * Each bailout or invariant in HIR lowering creates an {@link CompilerErrorDetail}, which is then
  * aggregated into a single {@link CompilerError} later.
@@ -101,24 +219,62 @@ export class CompilerErrorDetail {
     return this.options.suggestions;
   }
 
-  printErrorMessage(): string {
-    const buffer = [`${this.severity}: ${this.reason}`];
+  primaryLocation(): SourceLocation | null {
+    return this.loc;
+  }
+
+  printErrorMessage(source: string): string {
+    const buffer = [printErrorSummary(this.severity, this.reason)];
     if (this.description != null) {
-      buffer.push(`. ${this.description}`);
+      buffer.push(`\n\n${this.description}.`);
     }
-    if (this.loc != null && typeof this.loc !== 'symbol') {
-      buffer.push(` (${this.loc.start.line}:${this.loc.end.line})`);
+    const loc = this.loc;
+    if (loc != null && typeof loc !== 'symbol') {
+      let codeFrame: string;
+      try {
+        codeFrame = codeFrameColumns(
+          source,
+          {
+            start: {
+              line: loc.start.line,
+              column: loc.start.column + 1,
+            },
+            end: {
+              line: loc.end.line,
+              column: loc.end.column + 1,
+            },
+          },
+          {
+            message: this.reason,
+          },
+        );
+      } catch (e) {
+        codeFrame = '';
+      }
+      buffer.push(
+        `\n\n${loc.filename}:${loc.start.line}:${loc.start.column}\n`,
+      );
+      buffer.push(codeFrame);
+      buffer.push('\n\n');
     }
     return buffer.join('');
   }
 
   toString(): string {
-    return this.printErrorMessage();
+    const buffer = [printErrorSummary(this.severity, this.reason)];
+    if (this.description != null) {
+      buffer.push(`. ${this.description}.`);
+    }
+    const loc = this.loc;
+    if (loc != null && typeof loc !== 'symbol') {
+      buffer.push(` (${loc.start.line}:${loc.start.column})`);
+    }
+    return buffer.join('');
   }
 }
 
 export class CompilerError extends Error {
-  details: Array<CompilerErrorDetail> = [];
+  details: Array<CompilerErrorDetail | CompilerDiagnostic> = [];
 
   static invariant(
     condition: unknown,
@@ -136,6 +292,12 @@ export class CompilerError extends Error {
     }
   }
 
+  static throwDiagnostic(options: CompilerDiagnosticOptions): never {
+    const errors = new CompilerError();
+    errors.pushDiagnostic(new CompilerDiagnostic(options));
+    throw errors;
+  }
+
   static throwTodo(
     options: Omit<CompilerErrorDetailOptions, 'severity'>,
   ): never {
@@ -210,6 +372,21 @@ export class CompilerError extends Error {
     return this.name;
   }
 
+  printErrorMessage(source: string): string {
+    return (
+      `Found ${this.details.length} error${this.details.length === 1 ? '' : 's'}:\n` +
+      this.details.map(detail => detail.printErrorMessage(source)).join('\n')
+    );
+  }
+
+  merge(other: CompilerError): void {
+    this.details.push(...other.details);
+  }
+
+  pushDiagnostic(diagnostic: CompilerDiagnostic): void {
+    this.details.push(diagnostic);
+  }
+
   push(options: CompilerErrorDetailOptions): CompilerErrorDetail {
     const detail = new CompilerErrorDetail({
       reason: options.reason,
@@ -260,3 +437,32 @@ export class CompilerError extends Error {
     });
   }
 }
+
+function printErrorSummary(severity: ErrorSeverity, message: string): string {
+  let severityCategory: string;
+  switch (severity) {
+    case ErrorSeverity.InvalidConfig:
+    case ErrorSeverity.InvalidJS:
+    case ErrorSeverity.InvalidReact:
+    case ErrorSeverity.UnsupportedJS: {
+      severityCategory = 'Error';
+      break;
+    }
+    case ErrorSeverity.CannotPreserveMemoization: {
+      severityCategory = 'Memoization';
+      break;
+    }
+    case ErrorSeverity.Invariant: {
+      severityCategory = 'Invariant';
+      break;
+    }
+    case ErrorSeverity.Todo: {
+      severityCategory = 'Todo';
+      break;
+    }
+    default: {
+      assertExhaustive(severity, `Unexpected severity '${severity}'`);
+    }
+  }
+  return `${severityCategory}: ${message}`;
+}

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

@@ -7,7 +7,12 @@
 
 import * as t from '@babel/types';
 import {z} from 'zod';
-import {CompilerError, CompilerErrorDetailOptions} from '../CompilerError';
+import {
+  CompilerDiagnostic,
+  CompilerError,
+  CompilerErrorDetail,
+  CompilerErrorDetailOptions,
+} from '../CompilerError';
 import {
   EnvironmentConfig,
   ExternalFunction,
@@ -224,7 +229,7 @@ export type LoggerEvent =
 export type CompileErrorEvent = {
   kind: 'CompileError';
   fnLoc: t.SourceLocation | null;
-  detail: CompilerErrorDetailOptions;
+  detail: CompilerErrorDetail | CompilerDiagnostic;
 };
 export type CompileDiagnosticEvent = {
   kind: 'CompileDiagnostic';

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

@@ -181,7 +181,7 @@ function logError(
         context.opts.logger.logEvent(context.filename, {
           kind: 'CompileError',
           fnLoc,
-          detail: detail.options,
+          detail,
         });
       }
     } else {

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

@@ -8,32 +8,27 @@
 import {NodePath} from '@babel/core';
 import * as t from '@babel/types';
 
-import {
-  CompilerError,
-  CompilerErrorDetailOptions,
-  EnvironmentConfig,
-  ErrorSeverity,
-  Logger,
-} from '..';
+import {CompilerError, EnvironmentConfig, ErrorSeverity, Logger} from '..';
 import {getOrInsertWith} from '../Utils/utils';
-import {Environment} from '../HIR';
+import {Environment, GeneratedSource} from '../HIR';
 import {DEFAULT_EXPORT} from '../HIR/Environment';
 import {CompileProgramMetadata} from './Program';
+import {CompilerDiagnostic, CompilerDiagnosticOptions} from '../CompilerError';
 
 function throwInvalidReact(
-  options: Omit<CompilerErrorDetailOptions, 'severity'>,
+  options: Omit<CompilerDiagnosticOptions, 'severity'>,
   {logger, filename}: TraversalState,
 ): never {
-  const detail: CompilerErrorDetailOptions = {
-    ...options,
+  const detail: CompilerDiagnosticOptions = {
     severity: ErrorSeverity.InvalidReact,
+    ...options,
   };
   logger?.logEvent(filename, {
     kind: 'CompileError',
     fnLoc: null,
-    detail,
+    detail: new CompilerDiagnostic(detail),
   });
-  CompilerError.throw(detail);
+  CompilerError.throwDiagnostic(detail);
 }
 
 function isAutodepsSigil(
@@ -97,14 +92,18 @@ function assertValidEffectImportReference(
          */
         throwInvalidReact(
           {
-            reason:
-              '[InferEffectDependencies] React Compiler is unable to infer dependencies of this effect. ' +
-              'This will break your build! ' +
-              'To resolve, either pass your own dependency array or fix reported compiler bailout diagnostics.',
-            description: maybeErrorDiagnostic
-              ? `(Bailout reason: ${maybeErrorDiagnostic})`
-              : null,
-            loc: parent.node.loc ?? null,
+            category:
+              'Cannot infer dependencies of this effect. This will break your build!',
+            description:
+              'To resolve, either pass a dependency array or fix reported compiler bailout diagnostics.' +
+              (maybeErrorDiagnostic ? ` ${maybeErrorDiagnostic}` : ''),
+            details: [
+              {
+                kind: 'error',
+                message: 'Cannot infer dependencies',
+                loc: parent.node.loc ?? GeneratedSource,
+              },
+            ],
           },
           context,
         );
@@ -124,13 +123,20 @@ function assertValidFireImportReference(
     );
     throwInvalidReact(
       {
-        reason:
-          '[Fire] Untransformed reference to compiler-required feature. ' +
-          'Either remove this `fire` call or ensure it is successfully transformed by the compiler',
-        description: maybeErrorDiagnostic
-          ? `(Bailout reason: ${maybeErrorDiagnostic})`
-          : null,
-        loc: paths[0].node.loc ?? null,
+        category:
+          '[Fire] Untransformed reference to compiler-required feature.',
+        description:
+          'Either remove this `fire` call or ensure it is successfully transformed by the compiler' +
+          maybeErrorDiagnostic
+            ? ` ${maybeErrorDiagnostic}`
+            : '',
+        details: [
+          {
+            kind: 'error',
+            message: 'Untransformed `fire` call',
+            loc: paths[0].node.loc ?? GeneratedSource,
+          },
+        ],
       },
       context,
     );

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

@@ -9,6 +9,7 @@ import {NodePath, Scope} from '@babel/traverse';
 import * as t from '@babel/types';
 import invariant from 'invariant';
 import {
+  CompilerDiagnostic,
   CompilerError,
   CompilerSuggestionOperation,
   ErrorSeverity,
@@ -104,12 +105,18 @@ export function lower(
     if (param.isIdentifier()) {
       const binding = builder.resolveIdentifier(param);
       if (binding.kind !== 'Identifier') {
-        builder.errors.push({
-          reason: `(BuildHIR::lower) Could not find binding for param \`${param.node.name}\``,
-          severity: ErrorSeverity.Invariant,
-          loc: param.node.loc ?? null,
-          suggestions: null,
-        });
+        builder.errors.pushDiagnostic(
+          CompilerDiagnostic.create({
+            category: 'Could not find binding',
+            description: `[BuildHIR] Could not find binding for param \`${param.node.name}\``,
+            severity: ErrorSeverity.Invariant,
+            suggestions: null,
+          }).withDetail({
+            kind: 'error',
+            loc: param.node.loc ?? null,
+            message: 'Could not find binding',
+          }),
+        );
         return;
       }
       const place: Place = {
@@ -163,12 +170,18 @@ export function lower(
         'Assignment',
       );
     } else {
-      builder.errors.push({
-        reason: `(BuildHIR::lower) Handle ${param.node.type} params`,
-        severity: ErrorSeverity.Todo,
-        loc: param.node.loc ?? null,
-        suggestions: null,
-      });
+      builder.errors.pushDiagnostic(
+        CompilerDiagnostic.create({
+          category: `Handle ${param.node.type} parameters`,
+          description: `[BuildHIR] Add support for ${param.node.type} parameters`,
+          severity: ErrorSeverity.Todo,
+          suggestions: null,
+        }).withDetail({
+          kind: 'error',
+          loc: param.node.loc ?? null,
+          message: 'Unsupported parameter type',
+        }),
+      );
     }
   });
 
@@ -188,13 +201,18 @@ export function lower(
     lowerStatement(builder, body);
     directives = body.get('directives').map(d => d.node.value.value);
   } else {
-    builder.errors.push({
-      severity: ErrorSeverity.InvalidJS,
-      reason: `Unexpected function body kind`,
-      description: `Expected function body to be an expression or a block statement, got \`${body.type}\``,
-      loc: body.node.loc ?? null,
-      suggestions: null,
-    });
+    builder.errors.pushDiagnostic(
+      CompilerDiagnostic.create({
+        severity: ErrorSeverity.InvalidJS,
+        category: `Unexpected function body kind`,
+        description: `Expected function body to be an expression or a block statement, got \`${body.type}\``,
+        suggestions: null,
+      }).withDetail({
+        kind: 'error',
+        loc: body.node.loc ?? null,
+        message: 'Expected a block statement or expression',
+      }),
+    );
   }
 
   if (builder.errors.hasErrors()) {
@@ -2271,11 +2289,17 @@ function lowerExpression(
         });
         for (const [name, locations] of Object.entries(fbtLocations)) {
           if (locations.length > 1) {
-            CompilerError.throwTodo({
-              reason: `Support <${tagName}> tags with multiple <${tagName}:${name}> values`,
-              loc: locations.at(-1) ?? GeneratedSource,
-              description: null,
-              suggestions: null,
+            CompilerError.throwDiagnostic({
+              severity: ErrorSeverity.Todo,
+              category: 'Support duplicate fbt tags',
+              description: `Support \`<${tagName}>\` tags with multiple \`<${tagName}:${name}>\` values`,
+              details: locations.map(loc => {
+                return {
+                  kind: 'error',
+                  message: `Multiple \`<${tagName}:${name}>\` tags found`,
+                  loc,
+                };
+              }),
             });
           }
         }
@@ -3503,9 +3527,8 @@ function lowerFunction(
   );
   let loweredFunc: HIRFunction;
   if (lowering.isErr()) {
-    lowering
-      .unwrapErr()
-      .details.forEach(detail => builder.errors.pushErrorDetail(detail));
+    const functionErrors = lowering.unwrapErr();
+    builder.errors.merge(functionErrors);
     return null;
   }
   loweredFunc = lowering.unwrap();

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

@@ -7,7 +7,7 @@
 
 import {Binding, NodePath} from '@babel/traverse';
 import * as t from '@babel/types';
-import {CompilerError} from '../CompilerError';
+import {CompilerError, ErrorSeverity} from '../CompilerError';
 import {Environment} from './Environment';
 import {
   BasicBlock,
@@ -308,9 +308,18 @@ export default class HIRBuilder {
 
   resolveBinding(node: t.Identifier): Identifier {
     if (node.name === 'fbt') {
-      CompilerError.throwTodo({
-        reason: 'Support local variables named "fbt"',
-        loc: node.loc ?? null,
+      CompilerError.throwDiagnostic({
+        severity: ErrorSeverity.Todo,
+        category: 'Support local variables named `fbt`',
+        description:
+          'Local variables named `fbt` may conflict with the fbt plugin and are not yet supported',
+        details: [
+          {
+            kind: 'error',
+            message: 'Rename to avoid conflict with fbt plugin',
+            loc: node.loc ?? GeneratedSource,
+          },
+        ],
       });
     }
     const originalName = node.name;

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

@@ -995,13 +995,13 @@ export function printAliasingEffect(effect: AliasingEffect): string {
       return `${effect.kind} ${printPlaceForAliasEffect(effect.value)}`;
     }
     case 'MutateFrozen': {
-      return `MutateFrozen ${printPlaceForAliasEffect(effect.place)} reason=${JSON.stringify(effect.error.reason)}`;
+      return `MutateFrozen ${printPlaceForAliasEffect(effect.place)} reason=${JSON.stringify(effect.error.category)}`;
     }
     case 'MutateGlobal': {
-      return `MutateGlobal ${printPlaceForAliasEffect(effect.place)} reason=${JSON.stringify(effect.error.reason)}`;
+      return `MutateGlobal ${printPlaceForAliasEffect(effect.place)} reason=${JSON.stringify(effect.error.category)}`;
     }
     case 'Impure': {
-      return `Impure ${printPlaceForAliasEffect(effect.place)} reason=${JSON.stringify(effect.error.reason)}`;
+      return `Impure ${printPlaceForAliasEffect(effect.place)} reason=${JSON.stringify(effect.error.category)}`;
     }
     case 'Render': {
       return `Render ${printPlaceForAliasEffect(effect.place)}`;

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

@@ -345,6 +345,51 @@ export function* eachPatternOperand(pattern: Pattern): Iterable<Place> {
   }
 }
 
+export function* eachPatternItem(
+  pattern: Pattern,
+): Iterable<Place | SpreadPattern> {
+  switch (pattern.kind) {
+    case 'ArrayPattern': {
+      for (const item of pattern.items) {
+        if (item.kind === 'Identifier') {
+          yield item;
+        } else if (item.kind === 'Spread') {
+          yield item;
+        } else if (item.kind === 'Hole') {
+          continue;
+        } else {
+          assertExhaustive(
+            item,
+            `Unexpected item kind \`${(item as any).kind}\``,
+          );
+        }
+      }
+      break;
+    }
+    case 'ObjectPattern': {
+      for (const property of pattern.properties) {
+        if (property.kind === 'ObjectProperty') {
+          yield property.place;
+        } else if (property.kind === 'Spread') {
+          yield property;
+        } else {
+          assertExhaustive(
+            property,
+            `Unexpected item kind \`${(property as any).kind}\``,
+          );
+        }
+      }
+      break;
+    }
+    default: {
+      assertExhaustive(
+        pattern,
+        `Unexpected pattern kind \`${(pattern as any).kind}\``,
+      );
+    }
+  }
+}
+
 export function mapInstructionLValues(
   instr: Instruction,
   fn: (place: Place) => Place,

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

@@ -5,7 +5,7 @@
  * LICENSE file in the root directory of this source tree.
  */
 
-import {CompilerErrorDetailOptions} from '../CompilerError';
+import {CompilerDiagnostic} from '../CompilerError';
 import {
   FunctionExpression,
   GeneratedSource,
@@ -133,19 +133,19 @@ export type AliasingEffect =
   /**
    * Mutation of a value known to be immutable
    */
-  | {kind: 'MutateFrozen'; place: Place; error: CompilerErrorDetailOptions}
+  | {kind: 'MutateFrozen'; place: Place; error: CompilerDiagnostic}
   /**
    * Mutation of a global
    */
   | {
       kind: 'MutateGlobal';
       place: Place;
-      error: CompilerErrorDetailOptions;
+      error: CompilerDiagnostic;
     }
   /**
    * Indicates a side-effect that is not safe during render
    */
-  | {kind: 'Impure'; place: Place; error: CompilerErrorDetailOptions}
+  | {kind: 'Impure'; place: Place; error: CompilerDiagnostic}
   /**
    * Indicates that a given place is accessed during render. Used to distingush
    * hook arguments that are known to be called immediately vs those used for
@@ -211,9 +211,9 @@ export function hashEffect(effect: AliasingEffect): string {
         effect.kind,
         effect.place.identifier.id,
         effect.error.severity,
-        effect.error.reason,
+        effect.error.category,
         effect.error.description,
-        printSourceLocation(effect.error.loc ?? GeneratedSource),
+        printSourceLocation(effect.error.primaryLocation() ?? GeneratedSource),
       ].join(':');
     }
     case 'Mutate':

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

@@ -326,26 +326,26 @@ function isEffectSafeOutsideRender(effect: FunctionEffect): boolean {
 
 export function getWriteErrorReason(abstractValue: AbstractValue): string {
   if (abstractValue.reason.has(ValueReason.Global)) {
-    return 'Writing to a variable defined outside a component or hook is not allowed. Consider using an effect';
+    return 'Modifying a variable defined outside a component or hook is not allowed. Consider using an effect';
   } else if (abstractValue.reason.has(ValueReason.JsxCaptured)) {
-    return 'Updating a value used previously in JSX is not allowed. Consider moving the mutation before the JSX';
+    return 'Modifying a value used previously in JSX is not allowed. Consider moving the modification before the JSX';
   } else if (abstractValue.reason.has(ValueReason.Context)) {
-    return `Mutating a value returned from 'useContext()', which should not be mutated`;
+    return `Modifying a value returned from 'useContext()' is not allowed.`;
   } else if (abstractValue.reason.has(ValueReason.KnownReturnSignature)) {
-    return 'Mutating a value returned from a function whose return value should not be mutated';
+    return 'Modifying a value returned from a function whose return value should not be mutated';
   } else if (abstractValue.reason.has(ValueReason.ReactiveFunctionArgument)) {
-    return 'Mutating component props or hook arguments is not allowed. Consider using a local variable instead';
+    return 'Modifying component props or hook arguments is not allowed. Consider using a local variable instead';
   } else if (abstractValue.reason.has(ValueReason.State)) {
-    return "Mutating a value returned from 'useState()', which should not be mutated. Use the setter function to update instead";
+    return "Modifying a value returned from 'useState()', which should not be modified directly. Use the setter function to update instead";
   } else if (abstractValue.reason.has(ValueReason.ReducerState)) {
-    return "Mutating a value returned from 'useReducer()', which should not be mutated. Use the dispatch function to update instead";
+    return "Modifying a value returned from 'useReducer()', which should not be modified directly. Use the dispatch function to update instead";
   } else if (abstractValue.reason.has(ValueReason.Effect)) {
-    return 'Updating a value used previously in an effect function or as an effect dependency is not allowed. Consider moving the mutation before calling useEffect()';
+    return 'Modifying a value used previously in an effect function or as an effect dependency is not allowed. Consider moving the modification before calling useEffect()';
   } else if (abstractValue.reason.has(ValueReason.HookCaptured)) {
-    return 'Updating a value previously passed as an argument to a hook is not allowed. Consider moving the mutation before calling the hook';
+    return 'Modifying a value previously passed as an argument to a hook is not allowed. Consider moving the modification before calling the hook';
   } else if (abstractValue.reason.has(ValueReason.HookReturn)) {
-    return 'Updating a value returned from a hook is not allowed. Consider moving the mutation into the hook where the value is constructed';
+    return 'Modifying a value returned from a hook is not allowed. Consider moving the modification into the hook where the value is constructed';
   } else {
-    return 'This mutates a variable that React considers immutable';
+    return 'This modifies a variable that React considers immutable';
   }
 }

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

@@ -6,6 +6,7 @@
  */
 
 import {
+  CompilerDiagnostic,
   CompilerError,
   Effect,
   ErrorSeverity,
@@ -36,8 +37,8 @@ import {
   ValueReason,
 } from '../HIR';
 import {
-  eachInstructionValueLValue,
   eachInstructionValueOperand,
+  eachPatternItem,
   eachTerminalOperand,
   eachTerminalSuccessor,
 } from '../HIR/visitors';
@@ -446,20 +447,24 @@ function applySignature(
               reason: value.reason,
               context: new Set(),
             });
+            const message =
+              effect.value.identifier.name !== null &&
+              effect.value.identifier.name.kind === 'named'
+                ? `\`${effect.value.identifier.name.value}\` cannot be modified`
+                : 'This value cannot be modified';
             effects.push({
               kind: 'MutateFrozen',
               place: effect.value,
-              error: {
+              error: CompilerDiagnostic.create({
                 severity: ErrorSeverity.InvalidReact,
-                reason,
-                description:
-                  effect.value.identifier.name !== null &&
-                  effect.value.identifier.name.kind === 'named'
-                    ? `Found mutation of \`${effect.value.identifier.name.value}\``
-                    : null,
-                loc: effect.value.loc,
+                category: 'This value cannot be modified',
+                description: reason,
                 suggestions: null,
-              },
+              }).withDetail({
+                kind: 'error',
+                loc: effect.value.loc,
+                message,
+              }),
             });
           }
         }
@@ -1016,30 +1021,28 @@ function applyEffect(
           const description =
             effect.value.identifier.name !== null &&
             effect.value.identifier.name.kind === 'named'
-              ? `Variable \`${effect.value.identifier.name.value}\` is accessed before it is declared`
-              : null;
+              ? `Variable \`${effect.value.identifier.name.value}\``
+              : 'This variable';
           const hoistedAccess = context.hoistedContextDeclarations.get(
             effect.value.identifier.declarationId,
           );
+          const diagnostic = CompilerDiagnostic.create({
+            severity: ErrorSeverity.InvalidReact,
+            category: 'Cannot access variable before it is declared',
+            description: `${description} is accessed before it is declared, which prevents the earlier access from updating when this value changes over time`,
+          });
           if (hoistedAccess != null && hoistedAccess.loc != effect.value.loc) {
-            applyEffect(
-              context,
-              state,
-              {
-                kind: 'MutateFrozen',
-                place: effect.value,
-                error: {
-                  severity: ErrorSeverity.InvalidReact,
-                  reason: `This variable is accessed before it is declared, which may prevent it from updating as the assigned value changes over time`,
-                  description,
-                  loc: hoistedAccess.loc,
-                  suggestions: null,
-                },
-              },
-              initialized,
-              effects,
-            );
+            diagnostic.withDetail({
+              kind: 'error',
+              loc: hoistedAccess.loc,
+              message: 'Variable accessed before it is declared',
+            });
           }
+          diagnostic.withDetail({
+            kind: 'error',
+            loc: effect.value.loc,
+            message: 'The variable is declared here',
+          });
 
           applyEffect(
             context,
@@ -1047,13 +1050,7 @@ function applyEffect(
             {
               kind: 'MutateFrozen',
               place: effect.value,
-              error: {
-                severity: ErrorSeverity.InvalidReact,
-                reason: `This variable is accessed before it is declared, which prevents the earlier access from updating when this value changes over time`,
-                description,
-                loc: effect.value.loc,
-                suggestions: null,
-              },
+              error: diagnostic,
             },
             initialized,
             effects,
@@ -1064,11 +1061,11 @@ function applyEffect(
             reason: value.reason,
             context: new Set(),
           });
-          const description =
+          const message =
             effect.value.identifier.name !== null &&
             effect.value.identifier.name.kind === 'named'
-              ? `Found mutation of \`${effect.value.identifier.name.value}\``
-              : null;
+              ? `\`${effect.value.identifier.name.value}\` cannot be modified`
+              : 'This value cannot be modified';
           applyEffect(
             context,
             state,
@@ -1078,13 +1075,15 @@ function applyEffect(
                   ? 'MutateFrozen'
                   : 'MutateGlobal',
               place: effect.value,
-              error: {
+              error: CompilerDiagnostic.create({
                 severity: ErrorSeverity.InvalidReact,
-                reason,
-                description,
+                category: 'This value cannot be modified',
+                description: reason,
+              }).withDetail({
+                kind: 'error',
                 loc: effect.value.loc,
-                suggestions: null,
-              },
+                message,
+              }),
             },
             initialized,
             effects,
@@ -1864,19 +1863,34 @@ function computeSignatureForInstruction(
       break;
     }
     case 'Destructure': {
-      for (const patternLValue of eachInstructionValueLValue(value)) {
-        if (isPrimitiveType(patternLValue.identifier)) {
+      for (const patternItem of eachPatternItem(value.lvalue.pattern)) {
+        const place =
+          patternItem.kind === 'Identifier' ? patternItem : patternItem.place;
+        if (isPrimitiveType(place.identifier)) {
           effects.push({
             kind: 'Create',
-            into: patternLValue,
+            into: place,
             value: ValueKind.Primitive,
             reason: ValueReason.Other,
           });
-        } else {
+        } else if (patternItem.kind === 'Identifier') {
           effects.push({
             kind: 'CreateFrom',
             from: value.value,
-            into: patternLValue,
+            into: place,
+          });
+        } else {
+          // Spread creates a new object/array that captures from the RValue
+          effects.push({
+            kind: 'Create',
+            into: place,
+            reason: ValueReason.Other,
+            value: ValueKind.Mutable,
+          });
+          effects.push({
+            kind: 'Capture',
+            from: value.value,
+            into: place,
           });
         }
       }
@@ -1991,13 +2005,18 @@ function computeSignatureForInstruction(
       effects.push({
         kind: 'MutateGlobal',
         place: value.value,
-        error: {
-          reason:
-            'Unexpected reassignment of a variable which was defined outside of the component. Components and hooks should be pure and side-effect free, but variable reassignment is a form of side-effect. If this variable is used in rendering, use useState instead. (https://react.dev/reference/rules/components-and-hooks-must-be-pure#side-effects-must-run-outside-of-render)',
-          loc: instr.loc,
-          suggestions: null,
+        error: CompilerDiagnostic.create({
           severity: ErrorSeverity.InvalidReact,
-        },
+          category:
+            'Cannot reassign variables declared outside of the component/hook',
+          description:
+            'Reassigning a variable declared outside of the component/hook is a form of side effect, which can cause unpredictable behavior depending on when the component happens to re-render. If this variable is used in rendering, use useState instead. Otherwise, consider updating it in an effect (https://react.dev/reference/rules/components-and-hooks-must-be-pure#side-effects-must-run-outside-of-render)',
+          suggestions: null,
+        }).withDetail({
+          kind: 'error',
+          loc: instr.loc,
+          message: 'Cannot reassign variable',
+        }),
       });
       effects.push({kind: 'Assign', from: value.value, into: lvalue});
       break;
@@ -2087,17 +2106,20 @@ function computeEffectsForLegacySignature(
     effects.push({
       kind: 'Impure',
       place: receiver,
-      error: {
-        reason:
-          'Calling an impure function can produce unstable results. (https://react.dev/reference/rules/components-and-hooks-must-be-pure#components-and-hooks-must-be-idempotent)',
-        description:
-          signature.canonicalName != null
-            ? `\`${signature.canonicalName}\` is an impure function whose results may change on every call`
-            : null,
+      error: CompilerDiagnostic.create({
         severity: ErrorSeverity.InvalidReact,
-        loc,
+        category: 'Cannot call impure function during render',
+        description:
+          (signature.canonicalName != null
+            ? `\`${signature.canonicalName}\` is an impure function. `
+            : '') +
+          'Calling an impure function can produce unstable results that update unpredictably when the component happens to re-render. (https://react.dev/reference/rules/components-and-hooks-must-be-pure#components-and-hooks-must-be-idempotent)',
         suggestions: null,
-      },
+      }).withDetail({
+        kind: 'error',
+        loc,
+        message: 'Cannot call impure function',
+      }),
     });
   }
   const stores: Array<Place> = [];

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

@@ -195,7 +195,7 @@ export function inferMutationAliasingRanges(
           effect.kind === 'MutateGlobal' ||
           effect.kind === 'Impure'
         ) {
-          errors.push(effect.error);
+          errors.pushDiagnostic(effect.error);
           functionEffects.push(effect);
         } else if (effect.kind === 'Render') {
           renders.push({index: index++, place: effect.place});
@@ -549,7 +549,7 @@ function appendFunctionErrors(errors: CompilerError, fn: HIRFunction): void {
       case 'Impure':
       case 'MutateFrozen':
       case 'MutateGlobal': {
-        errors.push(effect.error);
+        errors.pushDiagnostic(effect.error);
         break;
       }
     }

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

@@ -360,6 +360,12 @@ function* generateInstructionTypes(
                 value: makePropertyLiteral(propertyName),
               },
             });
+          } else if (item.kind === 'Spread') {
+            // Array pattern spread always creates an array
+            yield equation(item.place.identifier.type, {
+              kind: 'Object',
+              shapeId: BuiltInArrayId,
+            });
           } else {
             break;
           }

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

@@ -5,7 +5,7 @@
  * LICENSE file in the root directory of this source tree.
  */
 
-import {CompilerError, Effect} from '..';
+import {CompilerDiagnostic, CompilerError, Effect, ErrorSeverity} from '..';
 import {HIRFunction, IdentifierId, Place} from '../HIR';
 import {
   eachInstructionLValue,
@@ -28,16 +28,19 @@ export function validateLocalsNotReassignedAfterRender(fn: HIRFunction): void {
     false,
   );
   if (reassignment !== null) {
-    CompilerError.throwInvalidReact({
-      reason:
-        'Reassigning a variable after render has completed can cause inconsistent behavior on subsequent renders. Consider using state instead',
-      description:
-        reassignment.identifier.name !== null &&
-        reassignment.identifier.name.kind === 'named'
-          ? `Variable \`${reassignment.identifier.name.value}\` cannot be reassigned after render`
-          : '',
-      loc: reassignment.loc,
-    });
+    const errors = new CompilerError();
+    errors.pushDiagnostic(
+      CompilerDiagnostic.create({
+        severity: ErrorSeverity.InvalidReact,
+        category: 'Cannot reassign a variable after render completes',
+        description: `Reassigning ${reassignment.identifier.name != null && reassignment.identifier.name.kind === 'named' ? `variable \`${reassignment.identifier.name.value}\`` : 'a variable'} after render has completed can cause inconsistent behavior on subsequent renders. Consider using state instead`,
+      }).withDetail({
+        kind: 'error',
+        loc: reassignment.loc,
+        message: 'Cannot reassign variable after render completes',
+      }),
+    );
+    throw errors;
   }
 }
 

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

@@ -5,7 +5,7 @@
  * LICENSE file in the root directory of this source tree.
  */
 
-import {CompilerError, Effect, ErrorSeverity} from '..';
+import {CompilerDiagnostic, CompilerError, Effect, ErrorSeverity} from '..';
 import {
   FunctionEffect,
   HIRFunction,
@@ -57,16 +57,24 @@ export function validateNoFreezingKnownMutableFunctions(
     if (operand.effect === Effect.Freeze) {
       const effect = contextMutationEffects.get(operand.identifier.id);
       if (effect != null) {
-        errors.push({
-          reason: `This argument is a function which may reassign or mutate local variables after render, which can cause inconsistent behavior on subsequent renders. Consider using state instead`,
-          loc: operand.loc,
-          severity: ErrorSeverity.InvalidReact,
-        });
-        errors.push({
-          reason: `The function modifies a local variable here`,
-          loc: effect.loc,
-          severity: ErrorSeverity.InvalidReact,
-        });
+        errors.pushDiagnostic(
+          CompilerDiagnostic.create({
+            severity: ErrorSeverity.InvalidReact,
+            category: 'Cannot modify local variables after render completes',
+            description: `This argument is a function which may reassign or mutate local variables after render, which can cause inconsistent behavior on subsequent renders. Consider using state instead`,
+          })
+            .withDetail({
+              kind: 'error',
+              loc: operand.loc,
+              message:
+                'This function may (indirectly) reassign or modify local variables after render',
+            })
+            .withDetail({
+              kind: 'error',
+              loc: effect.loc,
+              message: 'This modifies a local variable',
+            }),
+        );
       }
     }
   }

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

@@ -5,7 +5,7 @@
  * LICENSE file in the root directory of this source tree.
  */
 
-import {CompilerError, ErrorSeverity} from '..';
+import {CompilerDiagnostic, CompilerError, ErrorSeverity} from '..';
 import {HIRFunction} from '../HIR';
 import {getFunctionCallSignature} from '../Inference/InferReferenceEffects';
 import {Result} from '../Utils/Result';
@@ -34,17 +34,22 @@ export function validateNoImpureFunctionsInRender(
           callee.identifier.type,
         );
         if (signature != null && signature.impure === true) {
-          errors.push({
-            reason:
-              'Calling an impure function can produce unstable results. (https://react.dev/reference/rules/components-and-hooks-must-be-pure#components-and-hooks-must-be-idempotent)',
-            description:
-              signature.canonicalName != null
-                ? `\`${signature.canonicalName}\` is an impure function whose results may change on every call`
-                : null,
-            severity: ErrorSeverity.InvalidReact,
-            loc: callee.loc,
-            suggestions: null,
-          });
+          errors.pushDiagnostic(
+            CompilerDiagnostic.create({
+              category: 'Cannot call impure function during render',
+              description:
+                (signature.canonicalName != null
+                  ? `\`${signature.canonicalName}\` is an impure function. `
+                  : '') +
+                'Calling an impure function can produce unstable results that update unpredictably when the component happens to re-render. (https://react.dev/reference/rules/components-and-hooks-must-be-pure#components-and-hooks-must-be-idempotent)',
+              severity: ErrorSeverity.InvalidReact,
+              suggestions: null,
+            }).withDetail({
+              kind: 'error',
+              loc: callee.loc,
+              message: 'Cannot call impure function',
+            }),
+          );
         }
       }
     }

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

@@ -5,7 +5,7 @@
  * LICENSE file in the root directory of this source tree.
  */
 
-import {CompilerError, ErrorSeverity} from '..';
+import {CompilerDiagnostic, CompilerError, ErrorSeverity} from '..';
 import {BlockId, HIRFunction} from '../HIR';
 import {Result} from '../Utils/Result';
 import {retainWhere} from '../Utils/utils';
@@ -34,11 +34,17 @@ export function validateNoJSXInTryStatement(
         switch (value.kind) {
           case 'JsxExpression':
           case 'JsxFragment': {
-            errors.push({
-              severity: ErrorSeverity.InvalidReact,
-              reason: `Unexpected JSX element within a try statement. To catch errors in rendering a given component, wrap that component in an error boundary. (https://react.dev/reference/react/Component#catching-rendering-errors-with-an-error-boundary)`,
-              loc: value.loc,
-            });
+            errors.pushDiagnostic(
+              CompilerDiagnostic.create({
+                severity: ErrorSeverity.InvalidReact,
+                category: 'Avoid constructing JSX within try/catch',
+                description: `React does not immediately render components when JSX is rendered, so any errors from this component will not be caught by the try/catch. To catch errors in rendering a given component, wrap that component in an error boundary. (https://react.dev/reference/react/Component#catching-rendering-errors-with-an-error-boundary)`,
+              }).withDetail({
+                kind: 'error',
+                loc: value.loc,
+                message: 'Avoid constructing JSX within try/catch',
+              }),
+            );
             break;
           }
         }

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

@@ -5,7 +5,11 @@
  * LICENSE file in the root directory of this source tree.
  */
 
-import {CompilerError, ErrorSeverity} from '../CompilerError';
+import {
+  CompilerDiagnostic,
+  CompilerError,
+  ErrorSeverity,
+} from '../CompilerError';
 import {
   HIRFunction,
   IdentifierId,
@@ -90,14 +94,21 @@ export function validateNoSetStateInEffects(
             if (arg !== undefined && arg.kind === 'Identifier') {
               const setState = setStateFunctions.get(arg.identifier.id);
               if (setState !== undefined) {
-                errors.push({
-                  reason:
-                    'Calling setState directly within a useEffect causes cascading renders and is not recommended. Consider alternatives to useEffect. (https://react.dev/learn/you-might-not-need-an-effect)',
-                  description: null,
-                  severity: ErrorSeverity.InvalidReact,
-                  loc: setState.loc,
-                  suggestions: null,
-                });
+                errors.pushDiagnostic(
+                  CompilerDiagnostic.create({
+                    category:
+                      'Calling setState within an effect can trigger cascading renders',
+                    description:
+                      'Calling setState directly within a useEffect causes cascading renders that can hurt performance, and is not recommended. Consider alternatives to useEffect. (https://react.dev/learn/you-might-not-need-an-effect)',
+                    severity: ErrorSeverity.InvalidReact,
+                    suggestions: null,
+                  }).withDetail({
+                    kind: 'error',
+                    loc: setState.loc,
+                    message:
+                      'Avoid calling setState() in the top-level of an effect',
+                  }),
+                );
               }
             }
           }

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

@@ -5,7 +5,11 @@
  * LICENSE file in the root directory of this source tree.
  */
 
-import {CompilerError, ErrorSeverity} from '../CompilerError';
+import {
+  CompilerDiagnostic,
+  CompilerError,
+  ErrorSeverity,
+} from '../CompilerError';
 import {HIRFunction, IdentifierId, isSetStateType} from '../HIR';
 import {computeUnconditionalBlocks} from '../HIR/ComputeUnconditionalBlocks';
 import {eachInstructionValueOperand} from '../HIR/visitors';
@@ -122,23 +126,35 @@ function validateNoSetStateInRenderImpl(
             unconditionalSetStateFunctions.has(callee.identifier.id)
           ) {
             if (activeManualMemoId !== null) {
-              errors.push({
-                reason:
-                  'Calling setState from useMemo may trigger an infinite loop. (https://react.dev/reference/react/useState)',
-                description: null,
-                severity: ErrorSeverity.InvalidReact,
-                loc: callee.loc,
-                suggestions: null,
-              });
+              errors.pushDiagnostic(
+                CompilerDiagnostic.create({
+                  category:
+                    'Calling setState from useMemo may trigger an infinite loop',
+                  description:
+                    'Each time the memo callback is evaluated it will change state. This can cause a memoization dependency to change, running the memo function again and causing an infinite loop. Instead of setting state in useMemo(), prefer deriving the value during render. (https://react.dev/reference/react/useState)',
+                  severity: ErrorSeverity.InvalidReact,
+                  suggestions: null,
+                }).withDetail({
+                  kind: 'error',
+                  loc: callee.loc,
+                  message: 'Found setState() within useMemo()',
+                }),
+              );
             } else if (unconditionalBlocks.has(block.id)) {
-              errors.push({
-                reason:
-                  'This is an unconditional set state during render, which will trigger an infinite loop. (https://react.dev/reference/react/useState)',
-                description: null,
-                severity: ErrorSeverity.InvalidReact,
-                loc: callee.loc,
-                suggestions: null,
-              });
+              errors.pushDiagnostic(
+                CompilerDiagnostic.create({
+                  category:
+                    'Calling setState during render may trigger an infinite loop',
+                  description:
+                    'Calling setState during render will trigger another render, and can lead to infinite loops. (https://react.dev/reference/react/useState)',
+                  severity: ErrorSeverity.InvalidReact,
+                  suggestions: null,
+                }).withDetail({
+                  kind: 'error',
+                  loc: callee.loc,
+                  message: 'Found setState() within useMemo()',
+                }),
+              );
             }
           }
           break;

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

@@ -5,7 +5,11 @@
  * LICENSE file in the root directory of this source tree.
  */
 
-import {CompilerError, ErrorSeverity} from '../CompilerError';
+import {
+  CompilerDiagnostic,
+  CompilerError,
+  ErrorSeverity,
+} from '../CompilerError';
 import {
   DeclarationId,
   Effect,
@@ -275,27 +279,37 @@ function validateInferredDep(
       errorDiagnostic = merge(errorDiagnostic ?? compareResult, compareResult);
     }
   }
-  errorState.push({
-    severity: ErrorSeverity.CannotPreserveMemoization,
-    reason:
-      'React Compiler has skipped optimizing this component because the existing manual memoization could not be preserved. The inferred dependencies did not match the manually specified dependencies, which could cause the value to change more or less frequently than expected',
-    description:
-      DEBUG ||
-      // If the dependency is a named variable then we can report it. Otherwise only print in debug mode
-      (dep.identifier.name != null && dep.identifier.name.kind === 'named')
-        ? `The inferred dependency was \`${prettyPrintScopeDependency(
-            dep,
-          )}\`, but the source dependencies were [${validDepsInMemoBlock
-            .map(dep => printManualMemoDependency(dep, true))
-            .join(', ')}]. ${
-            errorDiagnostic
-              ? getCompareDependencyResultDescription(errorDiagnostic)
-              : 'Inferred dependency not present in source'
-          }`
-        : null,
-    loc: memoLocation,
-    suggestions: null,
-  });
+  errorState.pushDiagnostic(
+    CompilerDiagnostic.create({
+      severity: ErrorSeverity.CannotPreserveMemoization,
+      category:
+        'Compilation skipped because existing memoization could not be preserved',
+      description: [
+        'React Compiler has skipped optimizing this component because the existing manual memoization could not be preserved. ',
+        'The inferred dependencies did not match the manually specified dependencies, which could cause the value to change more or less frequently than expected. ',
+        DEBUG ||
+        // If the dependency is a named variable then we can report it. Otherwise only print in debug mode
+        (dep.identifier.name != null && dep.identifier.name.kind === 'named')
+          ? `The inferred dependency was \`${prettyPrintScopeDependency(
+              dep,
+            )}\`, but the source dependencies were [${validDepsInMemoBlock
+              .map(dep => printManualMemoDependency(dep, true))
+              .join(', ')}]. ${
+              errorDiagnostic
+                ? getCompareDependencyResultDescription(errorDiagnostic)
+                : 'Inferred dependency not present in source'
+            }.`
+          : '',
+      ]
+        .join('')
+        .trim(),
+      suggestions: null,
+    }).withDetail({
+      kind: 'error',
+      loc: memoLocation,
+      message: 'Could not preserve existing manual memoization',
+    }),
+  );
 }
 
 class Visitor extends ReactiveFunctionVisitor<VisitorState> {
@@ -519,14 +533,21 @@ class Visitor extends ReactiveFunctionVisitor<VisitorState> {
           !this.scopes.has(identifier.scope.id) &&
           !this.prunedScopes.has(identifier.scope.id)
         ) {
-          state.errors.push({
-            reason:
-              'React Compiler has skipped optimizing this component because the existing manual memoization could not be preserved. This dependency may be mutated later, which could cause the value to change unexpectedly',
-            description: null,
-            severity: ErrorSeverity.CannotPreserveMemoization,
-            loc,
-            suggestions: null,
-          });
+          state.errors.pushDiagnostic(
+            CompilerDiagnostic.create({
+              severity: ErrorSeverity.CannotPreserveMemoization,
+              category:
+                'Compilation skipped because existing memoization could not be preserved',
+              description: [
+                'React Compiler has skipped optimizing this component because the existing manual memoization could not be preserved. ',
+                'This dependency may be mutated later, which could cause the value to change unexpectedly.',
+              ].join(''),
+            }).withDetail({
+              kind: 'error',
+              loc,
+              message: 'This dependency may be modified later',
+            }),
+          );
         }
       }
     }
@@ -560,16 +581,25 @@ class Visitor extends ReactiveFunctionVisitor<VisitorState> {
 
           for (const identifier of decls) {
             if (isUnmemoized(identifier, this.scopes)) {
-              state.errors.push({
-                reason:
-                  'React Compiler has skipped optimizing this component because the existing manual memoization could not be preserved. This value was memoized in source but not in compilation output.',
-                description: DEBUG
-                  ? `${printIdentifier(identifier)} was not memoized`
-                  : null,
-                severity: ErrorSeverity.CannotPreserveMemoization,
-                loc,
-                suggestions: null,
-              });
+              state.errors.pushDiagnostic(
+                CompilerDiagnostic.create({
+                  severity: ErrorSeverity.CannotPreserveMemoization,
+                  category:
+                    'Compilation skipped because existing memoization could not be preserved',
+                  description: [
+                    'React Compiler has skipped optimizing this component because the existing manual memoization could not be preserved. This value was memoized in source but not in compilation output. ',
+                    DEBUG
+                      ? `${printIdentifier(identifier)} was not memoized.`
+                      : '',
+                  ]
+                    .join('')
+                    .trim(),
+                }).withDetail({
+                  kind: 'error',
+                  loc,
+                  message: 'Could not preserve existing memoization',
+                }),
+              );
             }
           }
         }

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

@@ -5,7 +5,11 @@
  * LICENSE file in the root directory of this source tree.
  */
 
-import {CompilerError, ErrorSeverity} from '..';
+import {
+  CompilerDiagnostic,
+  CompilerError,
+  ErrorSeverity,
+} from '../CompilerError';
 import {FunctionExpression, HIRFunction, IdentifierId} from '../HIR';
 import {Result} from '../Utils/Result';
 
@@ -63,24 +67,41 @@ export function validateUseMemo(fn: HIRFunction): Result<void, CompilerError> {
           }
 
           if (body.loweredFunc.func.params.length > 0) {
-            errors.push({
-              severity: ErrorSeverity.InvalidReact,
-              reason: 'useMemo callbacks may not accept any arguments',
-              description: null,
-              loc: body.loc,
-              suggestions: null,
-            });
+            const firstParam = body.loweredFunc.func.params[0];
+            const loc =
+              firstParam.kind === 'Identifier'
+                ? firstParam.loc
+                : firstParam.place.loc;
+            errors.pushDiagnostic(
+              CompilerDiagnostic.create({
+                severity: ErrorSeverity.InvalidReact,
+                category: 'useMemo() callbacks may not accept parameters',
+                description:
+                  'useMemo() callbacks are called by React to cache calculations across re-renders. They should not take parameters. Instead, directly reference the props, state, or local variables needed for the computation.',
+                suggestions: null,
+              }).withDetail({
+                kind: 'error',
+                loc,
+                message: '',
+              }),
+            );
           }
 
           if (body.loweredFunc.func.async || body.loweredFunc.func.generator) {
-            errors.push({
-              severity: ErrorSeverity.InvalidReact,
-              reason:
-                'useMemo callbacks may not be async or generator functions',
-              description: null,
-              loc: body.loc,
-              suggestions: null,
-            });
+            errors.pushDiagnostic(
+              CompilerDiagnostic.create({
+                severity: ErrorSeverity.InvalidReact,
+                category:
+                  'useMemo callbacks may not be async or generator functions',
+                description:
+                  'useMemo() callbacks are called once and must synchronously return a value',
+                suggestions: null,
+              }).withDetail({
+                kind: 'error',
+                loc: body.loc,
+                message: 'Async and generator functions are not supported',
+              }),
+            );
           }
 
           break;

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

@@ -20,7 +20,7 @@ describe('parseConfigPragma()', () => {
         validateHooksUsage: 1,
       } as any);
     }).toThrowErrorMatchingInlineSnapshot(
-      `"InvalidConfig: Could not validate environment config. Update React Compiler config to fix the error. Validation error: 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(
-      `"InvalidConfig: 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/array-pattern-spread-creates-array.expect.md

@@ -0,0 +1,104 @@
+
+## Input
+
+```javascript
+// @validatePreserveExistingMemoizationGuarantees
+import {useMemo} from 'react';
+import {makeObject_Primitives, ValidateMemoization} from 'shared-runtime';
+
+function Component(props) {
+  // Should memoize independently
+  const x = useMemo(() => makeObject_Primitives(), []);
+
+  const rest = useMemo(() => {
+    const [_, ...rest] = props.array;
+
+    // Should be inferred as Array.proto.push which doesn't mutate input
+    rest.push(x);
+    return rest;
+  });
+
+  return (
+    <>
+      <ValidateMemoization inputs={[]} output={x} />
+      <ValidateMemoization inputs={[props.array]} output={rest} />
+    </>
+  );
+}
+
+export const FIXTURE_ENTRYPOINT = {
+  fn: Component,
+  params: [{array: [0, 1, 2]}],
+};
+
+```
+
+## Code
+
+```javascript
+import { c as _c } from "react/compiler-runtime"; // @validatePreserveExistingMemoizationGuarantees
+import { useMemo } from "react";
+import { makeObject_Primitives, ValidateMemoization } from "shared-runtime";
+
+function Component(props) {
+  const $ = _c(9);
+  let t0;
+  if ($[0] === Symbol.for("react.memo_cache_sentinel")) {
+    t0 = makeObject_Primitives();
+    $[0] = t0;
+  } else {
+    t0 = $[0];
+  }
+  const x = t0;
+  let rest;
+  if ($[1] !== props.array) {
+    [, ...rest] = props.array;
+
+    rest.push(x);
+    $[1] = props.array;
+    $[2] = rest;
+  } else {
+    rest = $[2];
+  }
+  const rest_0 = rest;
+  let t1;
+  if ($[3] === Symbol.for("react.memo_cache_sentinel")) {
+    t1 = <ValidateMemoization inputs={[]} output={x} />;
+    $[3] = t1;
+  } else {
+    t1 = $[3];
+  }
+  let t2;
+  if ($[4] !== props.array) {
+    t2 = [props.array];
+    $[4] = props.array;
+    $[5] = t2;
+  } else {
+    t2 = $[5];
+  }
+  let t3;
+  if ($[6] !== rest_0 || $[7] !== t2) {
+    t3 = (
+      <>
+        {t1}
+        <ValidateMemoization inputs={t2} output={rest_0} />
+      </>
+    );
+    $[6] = rest_0;
+    $[7] = t2;
+    $[8] = t3;
+  } else {
+    t3 = $[8];
+  }
+  return t3;
+}
+
+export const FIXTURE_ENTRYPOINT = {
+  fn: Component,
+  params: [{ array: [0, 1, 2] }],
+};
+
+```
+      
+### Eval output
+(kind: ok) <div>{"inputs":[],"output":{"a":0,"b":"value1","c":true}}</div><div>{"inputs":[[0,1,2]],"output":[1,2,{"a":0,"b":"value1","c":true}]}</div>

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

@@ -0,0 +1,28 @@
+// @validatePreserveExistingMemoizationGuarantees
+import {useMemo} from 'react';
+import {makeObject_Primitives, ValidateMemoization} from 'shared-runtime';
+
+function Component(props) {
+  // Should memoize independently
+  const x = useMemo(() => makeObject_Primitives(), []);
+
+  const rest = useMemo(() => {
+    const [_, ...rest] = props.array;
+
+    // Should be inferred as Array.proto.push which doesn't mutate input
+    rest.push(x);
+    return rest;
+  });
+
+  return (
+    <>
+      <ValidateMemoization inputs={[]} output={x} />
+      <ValidateMemoization inputs={[props.array]} output={rest} />
+    </>
+  );
+}
+
+export const FIXTURE_ENTRYPOINT = {
+  fn: Component,
+  params: [{array: [0, 1, 2]}],
+};

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error._todo.computed-lval-in-destructure.expect.md

@@ -15,13 +15,19 @@ function Component(props) {
 ## Error
 
 ```
+Found 1 error:
+Todo: (BuildHIR::lowerAssignment) Handle computed properties in ObjectPattern
+
+error._todo.computed-lval-in-destructure.ts:3:9
   1 | function Component(props) {
   2 |   const computedKey = props.key;
 > 3 |   const {[computedKey]: x} = props.val;
-    |          ^^^^^^^^^^^^^^^^ Todo: (BuildHIR::lowerAssignment) Handle computed properties in ObjectPattern (3:3)
+    |          ^^^^^^^^^^^^^^^^ (BuildHIR::lowerAssignment) Handle computed properties in ObjectPattern
   4 |
   5 |   return x;
   6 | }
+
+
 ```
           
       

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.assign-global-in-component-tag-function.expect.md

@@ -15,10 +15,16 @@ function Component() {
 ## Error
 
 ```
+Found 1 error:
+Error: Cannot reassign variables declared outside of the component/hook
+
+Reassigning a variable declared outside of the component/hook is a form of side effect, which can cause unpredictable behavior depending on when the component happens to re-render. If this variable is used in rendering, use useState instead. Otherwise, consider updating it in an effect (https://react.dev/reference/rules/components-and-hooks-must-be-pure#side-effects-must-run-outside-of-render)
+
+error.assign-global-in-component-tag-function.ts:3:4
   1 | function Component() {
   2 |   const Foo = () => {
 > 3 |     someGlobal = true;
-    |     ^^^^^^^^^^ InvalidReact: Unexpected reassignment of a variable which was defined outside of the component. Components and hooks should be pure and side-effect free, but variable reassignment is a form of side-effect. If this variable is used in rendering, use useState instead. (https://react.dev/reference/rules/components-and-hooks-must-be-pure#side-effects-must-run-outside-of-render) (3:3)
+    |     ^^^^^^^^^^ Cannot reassign variable
   4 |   };
   5 |   return <Foo />;
   6 | }

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.assign-global-in-jsx-children.expect.md

@@ -18,10 +18,16 @@ function Component() {
 ## Error
 
 ```
+Found 1 error:
+Error: Cannot reassign variables declared outside of the component/hook
+
+Reassigning a variable declared outside of the component/hook is a form of side effect, which can cause unpredictable behavior depending on when the component happens to re-render. If this variable is used in rendering, use useState instead. Otherwise, consider updating it in an effect (https://react.dev/reference/rules/components-and-hooks-must-be-pure#side-effects-must-run-outside-of-render)
+
+error.assign-global-in-jsx-children.ts:3:4
   1 | function Component() {
   2 |   const foo = () => {
 > 3 |     someGlobal = true;
-    |     ^^^^^^^^^^ InvalidReact: Unexpected reassignment of a variable which was defined outside of the component. Components and hooks should be pure and side-effect free, but variable reassignment is a form of side-effect. If this variable is used in rendering, use useState instead. (https://react.dev/reference/rules/components-and-hooks-must-be-pure#side-effects-must-run-outside-of-render) (3:3)
+    |     ^^^^^^^^^^ Cannot reassign variable
   4 |   };
   5 |   // Children are generally access/called during render, so
   6 |   // modifying a global in a children function is almost

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.assign-global-in-jsx-spread-attribute.expect.md

@@ -16,13 +16,19 @@ function Component() {
 ## Error
 
 ```
+Found 1 error:
+Error: Unexpected reassignment of a variable which was defined outside of the component. Components and hooks should be pure and side-effect free, but variable reassignment is a form of side-effect. If this variable is used in rendering, use useState instead. (https://react.dev/reference/rules/components-and-hooks-must-be-pure#side-effects-must-run-outside-of-render)
+
+error.assign-global-in-jsx-spread-attribute.ts:4:4
   2 | function Component() {
   3 |   const foo = () => {
 > 4 |     someGlobal = true;
-    |     ^^^^^^^^^^ InvalidReact: Unexpected reassignment of a variable which was defined outside of the component. Components and hooks should be pure and side-effect free, but variable reassignment is a form of side-effect. If this variable is used in rendering, use useState instead. (https://react.dev/reference/rules/components-and-hooks-must-be-pure#side-effects-must-run-outside-of-render) (4:4)
+    |     ^^^^^^^^^^ Unexpected reassignment of a variable which was defined outside of the component. Components and hooks should be pure and side-effect free, but variable reassignment is a form of side-effect. If this variable is used in rendering, use useState instead. (https://react.dev/reference/rules/components-and-hooks-must-be-pure#side-effects-must-run-outside-of-render)
   5 |   };
   6 |   return <div {...foo} />;
   7 | }
+
+
 ```
           
       

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.bailout-on-flow-suppression.expect.md

@@ -16,13 +16,21 @@ function Foo(props) {
 ## Error
 
 ```
+Found 1 error:
+Error: React Compiler has skipped optimizing this component because one or more React rule violations were reported by Flow. React Compiler only works when your components follow all the rules of React, disabling them may result in unexpected or incorrect behavior
+
+$FlowFixMe[react-rule-hook].
+
+error.bailout-on-flow-suppression.ts:4:2
   2 |
   3 | function Foo(props) {
 > 4 |   // $FlowFixMe[react-rule-hook]
-    |   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ InvalidReact: React Compiler has skipped optimizing this component because one or more React rule violations were reported by Flow. React Compiler only works when your components follow all the rules of React, disabling them may result in unexpected or incorrect behavior. $FlowFixMe[react-rule-hook] (4:4)
+    |   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ React Compiler has skipped optimizing this component because one or more React rule violations were reported by Flow. React Compiler only works when your components follow all the rules of React, disabling them may result in unexpected or incorrect behavior
   5 |   useX();
   6 |   return null;
   7 | }
+
+
 ```
           
       

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.bailout-on-suppression-of-custom-rule.expect.md

@@ -19,15 +19,35 @@ function lowercasecomponent() {
 ## Error
 
 ```
+Found 2 errors:
+Error: React Compiler has skipped optimizing this component because one or more React ESLint rules were disabled. React Compiler only works when your components follow all the rules of React, disabling them may result in unexpected or incorrect behavior
+
+eslint-disable my-app/react-rule.
+
+error.bailout-on-suppression-of-custom-rule.ts:3:0
   1 | // @eslintSuppressionRules:["my-app","react-rule"]
   2 |
 > 3 | /* eslint-disable my-app/react-rule */
-    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ InvalidReact: React Compiler has skipped optimizing this component because one or more React ESLint rules were disabled. React Compiler only works when your components follow all the rules of React, disabling them may result in unexpected or incorrect behavior. eslint-disable my-app/react-rule (3:3)
-
-InvalidReact: React Compiler has skipped optimizing this component because one or more React ESLint rules were disabled. React Compiler only works when your components follow all the rules of React, disabling them may result in unexpected or incorrect behavior. eslint-disable-next-line my-app/react-rule (7:7)
+    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ React Compiler has skipped optimizing this component because one or more React ESLint rules were disabled. React Compiler only works when your components follow all the rules of React, disabling them may result in unexpected or incorrect behavior
   4 | function lowercasecomponent() {
   5 |   'use forget';
   6 |   const x = [];
+
+
+Error: React Compiler has skipped optimizing this component because one or more React ESLint rules were disabled. React Compiler only works when your components follow all the rules of React, disabling them may result in unexpected or incorrect behavior
+
+eslint-disable-next-line my-app/react-rule.
+
+error.bailout-on-suppression-of-custom-rule.ts:7:2
+   5 |   'use forget';
+   6 |   const x = [];
+>  7 |   // eslint-disable-next-line my-app/react-rule
+     |   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ React Compiler has skipped optimizing this component because one or more React ESLint rules were disabled. React Compiler only works when your components follow all the rules of React, disabling them may result in unexpected or incorrect behavior
+   8 |   return <div>{x}</div>;
+   9 | }
+  10 | /* eslint-enable my-app/react-rule */
+
+
 ```
           
       

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.bug-old-inference-false-positive-ref-validation-in-use-effect.expect.md

@@ -36,6 +36,12 @@ function Component() {
 ## Error
 
 ```
+Found 1 error:
+Error: Cannot modify local variables after render completes
+
+This argument is a function which may reassign or mutate local variables after render, which can cause inconsistent behavior on subsequent renders. Consider using state instead
+
+error.bug-old-inference-false-positive-ref-validation-in-use-effect.ts:20:12
   18 |   );
   19 |   const ref = useRef(null);
 > 20 |   useEffect(() => {
@@ -47,12 +53,19 @@ function Component() {
 > 23 |     }
      | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 > 24 |   }, [update]);
-     | ^^^^ InvalidReact: This argument is a function which may reassign or mutate local variables after render, which can cause inconsistent behavior on subsequent renders. Consider using state instead (20:24)
-
-InvalidReact: The function modifies a local variable here (14:14)
+     | ^^^^ This function may (indirectly) reassign or modify local variables after render
   25 |
   26 |   return 'ok';
   27 | }
+
+error.bug-old-inference-false-positive-ref-validation-in-use-effect.ts:14:6
+  12 |         ...partialParams,
+  13 |       };
+> 14 |       nextParams.param = 'value';
+     |       ^^^^^^^^^^ This modifies a local variable
+  15 |       console.log(nextParams);
+  16 |     },
+  17 |     [params]
 ```
           
       

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.call-args-destructuring-asignment-complex.expect.md

@@ -14,13 +14,19 @@ function Component(props) {
 ## Error
 
 ```
+Found 1 error:
+Invariant: Const declaration cannot be referenced as an expression
+
+error.call-args-destructuring-asignment-complex.ts:3:9
   1 | function Component(props) {
   2 |   let x = makeObject();
 > 3 |   x.foo(([[x]] = makeObject()));
-    |          ^^^^^ Invariant: Const declaration cannot be referenced as an expression (3:3)
+    |          ^^^^^ Const declaration cannot be referenced as an expression
   4 |   return x;
   5 | }
   6 |
+
+
 ```
           
       

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.capitalized-function-call-aliased.expect.md

@@ -14,12 +14,20 @@ function Foo() {
 ## Error
 
 ```
+Found 1 error:
+Error: Capitalized functions are reserved for components, which must be invoked with JSX. If this is a component, render it with JSX. Otherwise, ensure that it has no hook calls and rename it to begin with a lowercase letter. Alternatively, if you know for a fact that this function is not a component, you can allowlist it via the compiler config
+
+Bar may be a component..
+
+error.capitalized-function-call-aliased.ts:4:2
   2 | function Foo() {
   3 |   let x = Bar;
 > 4 |   x(); // ERROR
-    |   ^^^ InvalidReact: Capitalized functions are reserved for components, which must be invoked with JSX. If this is a component, render it with JSX. Otherwise, ensure that it has no hook calls and rename it to begin with a lowercase letter. Alternatively, if you know for a fact that this function is not a component, you can allowlist it via the compiler config. Bar may be a component. (4:4)
+    |   ^^^ Capitalized functions are reserved for components, which must be invoked with JSX. If this is a component, render it with JSX. Otherwise, ensure that it has no hook calls and rename it to begin with a lowercase letter. Alternatively, if you know for a fact that this function is not a component, you can allowlist it via the compiler config
   5 | }
   6 |
+
+
 ```
           
       

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

@@ -15,13 +15,21 @@ function Component() {
 ## Error
 
 ```
+Found 1 error:
+Error: Capitalized functions are reserved for components, which must be invoked with JSX. If this is a component, render it with JSX. Otherwise, ensure that it has no hook calls and rename it to begin with a lowercase letter. Alternatively, if you know for a fact that this function is not a component, you can allowlist it via the compiler config
+
+SomeFunc may be a component..
+
+error.capitalized-function-call.ts:3:12
   1 | // @validateNoCapitalizedCalls
   2 | function Component() {
 > 3 |   const x = SomeFunc();
-    |             ^^^^^^^^^^ InvalidReact: Capitalized functions are reserved for components, which must be invoked with JSX. If this is a component, render it with JSX. Otherwise, ensure that it has no hook calls and rename it to begin with a lowercase letter. Alternatively, if you know for a fact that this function is not a component, you can allowlist it via the compiler config. SomeFunc may be a component. (3:3)
+    |             ^^^^^^^^^^ Capitalized functions are reserved for components, which must be invoked with JSX. If this is a component, render it with JSX. Otherwise, ensure that it has no hook calls and rename it to begin with a lowercase letter. Alternatively, if you know for a fact that this function is not a component, you can allowlist it via the compiler config
   4 |
   5 |   return x;
   6 | }
+
+
 ```
           
       

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

@@ -15,13 +15,21 @@ function Component() {
 ## Error
 
 ```
+Found 1 error:
+Error: Capitalized functions are reserved for components, which must be invoked with JSX. If this is a component, render it with JSX. Otherwise, ensure that it has no hook calls and rename it to begin with a lowercase letter. Alternatively, if you know for a fact that this function is not a component, you can allowlist it via the compiler config
+
+SomeFunc may be a component..
+
+error.capitalized-method-call.ts:3:12
   1 | // @validateNoCapitalizedCalls
   2 | function Component() {
 > 3 |   const x = someGlobal.SomeFunc();
-    |             ^^^^^^^^^^^^^^^^^^^^^ InvalidReact: Capitalized functions are reserved for components, which must be invoked with JSX. If this is a component, render it with JSX. Otherwise, ensure that it has no hook calls and rename it to begin with a lowercase letter. Alternatively, if you know for a fact that this function is not a component, you can allowlist it via the compiler config. SomeFunc may be a component. (3:3)
+    |             ^^^^^^^^^^^^^^^^^^^^^ Capitalized functions are reserved for components, which must be invoked with JSX. If this is a component, render it with JSX. Otherwise, ensure that it has no hook calls and rename it to begin with a lowercase letter. Alternatively, if you know for a fact that this function is not a component, you can allowlist it via the compiler config
   4 |
   5 |   return x;
   6 | }
+
+
 ```
           
       

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

@@ -32,19 +32,55 @@ export const FIXTURE_ENTRYPOINT = {
 ## Error
 
 ```
+Found 4 errors:
+Error: This function accesses a ref value (the `current` property), which may not be accessed during render. (https://react.dev/reference/react/useRef)
+
+error.capture-ref-for-mutation.ts:12:13
   10 |   };
   11 |   const moveLeft = {
 > 12 |     handler: handleKey('left')(),
-     |              ^^^^^^^^^^^^^^^^^ InvalidReact: This function accesses a ref value (the `current` property), which may not be accessed during render. (https://react.dev/reference/react/useRef) (12:12)
-
-InvalidReact: Ref values (the `current` property) may not be accessed during render. (https://react.dev/reference/react/useRef) (12:12)
-
-InvalidReact: This function accesses a ref value (the `current` property), which may not be accessed during render. (https://react.dev/reference/react/useRef) (15:15)
-
-InvalidReact: Ref values (the `current` property) may not be accessed during render. (https://react.dev/reference/react/useRef) (15:15)
+     |              ^^^^^^^^^^^^^^^^^ This function accesses a ref value (the `current` property), which may not be accessed during render. (https://react.dev/reference/react/useRef)
   13 |   };
   14 |   const moveRight = {
   15 |     handler: handleKey('right')(),
+
+
+Error: Ref values (the `current` property) may not be accessed during render. (https://react.dev/reference/react/useRef)
+
+error.capture-ref-for-mutation.ts:12:13
+  10 |   };
+  11 |   const moveLeft = {
+> 12 |     handler: handleKey('left')(),
+     |              ^^^^^^^^^^^^^^^^^ Ref values (the `current` property) may not be accessed during render. (https://react.dev/reference/react/useRef)
+  13 |   };
+  14 |   const moveRight = {
+  15 |     handler: handleKey('right')(),
+
+
+Error: This function accesses a ref value (the `current` property), which may not be accessed during render. (https://react.dev/reference/react/useRef)
+
+error.capture-ref-for-mutation.ts:15:13
+  13 |   };
+  14 |   const moveRight = {
+> 15 |     handler: handleKey('right')(),
+     |              ^^^^^^^^^^^^^^^^^^ This function accesses a ref value (the `current` property), which may not be accessed during render. (https://react.dev/reference/react/useRef)
+  16 |   };
+  17 |   return [moveLeft, moveRight];
+  18 | }
+
+
+Error: Ref values (the `current` property) may not be accessed during render. (https://react.dev/reference/react/useRef)
+
+error.capture-ref-for-mutation.ts:15:13
+  13 |   };
+  14 |   const moveRight = {
+> 15 |     handler: handleKey('right')(),
+     |              ^^^^^^^^^^^^^^^^^^ Ref values (the `current` property) may not be accessed during render. (https://react.dev/reference/react/useRef)
+  16 |   };
+  17 |   return [moveLeft, moveRight];
+  18 | }
+
+
 ```
           
       

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.conditional-hook-unknown-hook-react-namespace.expect.md

@@ -16,13 +16,19 @@ function Component(props) {
 ## Error
 
 ```
+Found 1 error:
+Error: Hooks must always be called in a consistent order, and may not be called conditionally. See the Rules of Hooks (https://react.dev/warnings/invalid-hook-call-warning)
+
+error.conditional-hook-unknown-hook-react-namespace.ts:4:8
   2 |   let x = null;
   3 |   if (props.cond) {
 > 4 |     x = React.useNonexistentHook();
-    |         ^^^^^^^^^^^^^^^^^^^^^^^^ InvalidReact: Hooks must always be called in a consistent order, and may not be called conditionally. See the Rules of Hooks (https://react.dev/warnings/invalid-hook-call-warning) (4:4)
+    |         ^^^^^^^^^^^^^^^^^^^^^^^^ Hooks must always be called in a consistent order, and may not be called conditionally. See the Rules of Hooks (https://react.dev/warnings/invalid-hook-call-warning)
   5 |   }
   6 |   return x;
   7 | }
+
+
 ```
           
       

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.conditional-hooks-as-method-call.expect.md

@@ -16,13 +16,19 @@ function Component(props) {
 ## Error
 
 ```
+Found 1 error:
+Error: Hooks must always be called in a consistent order, and may not be called conditionally. See the Rules of Hooks (https://react.dev/warnings/invalid-hook-call-warning)
+
+error.conditional-hooks-as-method-call.ts:4:8
   2 |   let x = null;
   3 |   if (props.cond) {
 > 4 |     x = Foo.useFoo();
-    |         ^^^^^^^^^^ InvalidReact: Hooks must always be called in a consistent order, and may not be called conditionally. See the Rules of Hooks (https://react.dev/warnings/invalid-hook-call-warning) (4:4)
+    |         ^^^^^^^^^^ Hooks must always be called in a consistent order, and may not be called conditionally. See the Rules of Hooks (https://react.dev/warnings/invalid-hook-call-warning)
   5 |   }
   6 |   return x;
   7 | }
+
+
 ```
           
       

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.context-variable-only-chained-assign.expect.md

@@ -28,10 +28,16 @@ export const FIXTURE_ENTRYPOINT = {
 ## Error
 
 ```
+Found 1 error:
+Error: Cannot reassign a variable after render completes
+
+Reassigning variable `x` after render has completed can cause inconsistent behavior on subsequent renders. Consider using state instead
+
+error.context-variable-only-chained-assign.ts:10:19
    8 |   };
    9 |   const fn2 = () => {
 > 10 |     const copy2 = (x = 4);
-     |                    ^ InvalidReact: Reassigning a variable after render has completed can cause inconsistent behavior on subsequent renders. Consider using state instead. Variable `x` cannot be reassigned after render (10:10)
+     |                    ^ Cannot reassign variable after render completes
   11 |     return [invoke(fn1), copy2, identity(copy2)];
   12 |   };
   13 |   return invoke(fn2);

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.declare-reassign-variable-in-function-declaration.expect.md

@@ -17,10 +17,16 @@ function Component() {
 ## Error
 
 ```
+Found 1 error:
+Error: Cannot reassign a variable after render completes
+
+Reassigning variable `x` after render has completed can cause inconsistent behavior on subsequent renders. Consider using state instead
+
+error.declare-reassign-variable-in-function-declaration.ts:4:4
   2 |   let x = null;
   3 |   function foo() {
 > 4 |     x = 9;
-    |     ^ InvalidReact: Reassigning a variable after render has completed can cause inconsistent behavior on subsequent renders. Consider using state instead. Variable `x` cannot be reassigned after render (4:4)
+    |     ^ Cannot reassign variable after render completes
   5 |   }
   6 |   const y = bar(foo);
   7 |   return <Child y={y} />;

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.default-param-accesses-local.expect.md

@@ -22,6 +22,10 @@ export const FIXTURE_ENTRYPOINT = {
 ## Error
 
 ```
+Found 1 error:
+Todo: (BuildHIR::node.lowerReorderableExpression) Expression type `ArrowFunctionExpression` cannot be safely reordered
+
+error.default-param-accesses-local.ts:3:6
   1 | function Component(
   2 |   x,
 > 3 |   y = () => {
@@ -29,10 +33,12 @@ export const FIXTURE_ENTRYPOINT = {
 > 4 |     return x;
     | ^^^^^^^^^^^^^
 > 5 |   }
-    | ^^^^ Todo: (BuildHIR::node.lowerReorderableExpression) Expression type `ArrowFunctionExpression` cannot be safely reordered (3:5)
+    | ^^^^ (BuildHIR::node.lowerReorderableExpression) Expression type `ArrowFunctionExpression` cannot be safely reordered
   6 | ) {
   7 |   return y();
   8 | }
+
+
 ```
           
       

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.dont-hoist-inline-reference.expect.md

@@ -19,13 +19,21 @@ export const FIXTURE_ENTRYPOINT = {
 ## Error
 
 ```
+Found 1 error:
+Todo: [hoisting] EnterSSA: Expected identifier to be defined before being used
+
+Identifier x$1 is undefined.
+
+error.dont-hoist-inline-reference.ts:3:2
   1 | import {identity} from 'shared-runtime';
   2 | function useInvalid() {
 > 3 |   const x = identity(x);
-    |   ^^^^^^^^^^^^^^^^^^^^^^ Todo: [hoisting] EnterSSA: Expected identifier to be defined before being used. Identifier x$1 is undefined (3:3)
+    |   ^^^^^^^^^^^^^^^^^^^^^^ [hoisting] EnterSSA: Expected identifier to be defined before being used
   4 |   return x;
   5 | }
   6 |
+
+
 ```
           
       

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.emit-freeze-conflicting-global.expect.md

@@ -15,13 +15,21 @@ function useFoo(props) {
 ## Error
 
 ```
+Found 1 error:
+Todo: Encountered conflicting global in generated program
+
+Conflict from local binding __DEV__.
+
+error.emit-freeze-conflicting-global.ts:3:8
   1 | // @enableEmitFreeze @instrumentForget
   2 | function useFoo(props) {
 > 3 |   const __DEV__ = 'conflicting global';
-    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Todo: Encountered conflicting global in generated program. Conflict from local binding __DEV__ (3:3)
+    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Encountered conflicting global in generated program
   4 |   console.log(__DEV__);
   5 |   return foo(props.x);
   6 | }
+
+
 ```
           
       

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.function-expression-references-variable-its-assigned-to.expect.md

@@ -15,10 +15,16 @@ function Component() {
 ## Error
 
 ```
+Found 1 error:
+Error: Cannot reassign a variable after render completes
+
+Reassigning variable `callback` after render has completed can cause inconsistent behavior on subsequent renders. Consider using state instead
+
+error.function-expression-references-variable-its-assigned-to.ts:3:4
   1 | function Component() {
   2 |   let callback = () => {
 > 3 |     callback = null;
-    |     ^^^^^^^^ InvalidReact: Reassigning a variable after render has completed can cause inconsistent behavior on subsequent renders. Consider using state instead. Variable `callback` cannot be reassigned after render (3:3)
+    |     ^^^^^^^^ Cannot reassign variable after render completes
   4 |   };
   5 |   return <div onClick={callback} />;
   6 | }

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.hoist-optional-member-expression-with-conditional-optional.expect.md

@@ -24,6 +24,12 @@ function Component(props) {
 ## Error
 
 ```
+Found 1 error:
+Memoization: Compilation skipped because existing memoization could not be preserved
+
+React Compiler has skipped optimizing this component because the existing manual memoization could not be preserved. The inferred dependencies did not match the manually specified dependencies, which could cause the value to change more or less frequently than expected. The inferred dependency was `props.items`, but the source dependencies were [props?.items, props.cond]. Inferred different dependency than source.
+
+error.hoist-optional-member-expression-with-conditional-optional.ts:4:23
    2 | import {ValidateMemoization} from 'shared-runtime';
    3 | function Component(props) {
 >  4 |   const data = useMemo(() => {
@@ -41,7 +47,7 @@ function Component(props) {
 > 10 |     return x;
      | ^^^^^^^^^^^^^^^^^
 > 11 |   }, [props?.items, props.cond]);
-     | ^^^^ CannotPreserveMemoization: React Compiler has skipped optimizing this component because the existing manual memoization could not be preserved. The inferred dependencies did not match the manually specified dependencies, which could cause the value to change more or less frequently than expected. The inferred dependency was `props.items`, but the source dependencies were [props?.items, props.cond]. Inferred different dependency than source (4:11)
+     | ^^^^ Could not preserve existing manual memoization
   12 |   return (
   13 |     <ValidateMemoization inputs={[props?.items, props.cond]} output={data} />
   14 |   );

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.hoist-optional-member-expression-with-conditional.expect.md

@@ -24,6 +24,12 @@ function Component(props) {
 ## Error
 
 ```
+Found 1 error:
+Memoization: Compilation skipped because existing memoization could not be preserved
+
+React Compiler has skipped optimizing this component because the existing manual memoization could not be preserved. The inferred dependencies did not match the manually specified dependencies, which could cause the value to change more or less frequently than expected. The inferred dependency was `props.items`, but the source dependencies were [props?.items, props.cond]. Inferred different dependency than source.
+
+error.hoist-optional-member-expression-with-conditional.ts:4:23
    2 | import {ValidateMemoization} from 'shared-runtime';
    3 | function Component(props) {
 >  4 |   const data = useMemo(() => {
@@ -41,7 +47,7 @@ function Component(props) {
 > 10 |     return x;
      | ^^^^^^^^^^^^^^^^^
 > 11 |   }, [props?.items, props.cond]);
-     | ^^^^ CannotPreserveMemoization: React Compiler has skipped optimizing this component because the existing manual memoization could not be preserved. The inferred dependencies did not match the manually specified dependencies, which could cause the value to change more or less frequently than expected. The inferred dependency was `props.items`, but the source dependencies were [props?.items, props.cond]. Inferred different dependency than source (4:11)
+     | ^^^^ Could not preserve existing manual memoization
   12 |   return (
   13 |     <ValidateMemoization inputs={[props?.items, props.cond]} output={data} />
   14 |   );

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.hoisting-simple-function-declaration.expect.md

@@ -24,6 +24,10 @@ export const FIXTURE_ENTRYPOINT = {
 ## Error
 
 ```
+Found 1 error:
+Todo: Support functions with unreachable code that may contain hoisted declarations
+
+error.hoisting-simple-function-declaration.ts:6:2
    4 |   }
    5 |   return baz(); // OK: FuncDecls are HoistableDeclarations that have both declaration and value hoisting
 >  6 |   function baz() {
@@ -31,10 +35,12 @@ export const FIXTURE_ENTRYPOINT = {
 >  7 |     return bar();
      | ^^^^^^^^^^^^^^^^^
 >  8 |   }
-     | ^^^^ Todo: Support functions with unreachable code that may contain hoisted declarations (6:8)
+     | ^^^^ Support functions with unreachable code that may contain hoisted declarations
    9 | }
   10 |
   11 | export const FIXTURE_ENTRYPOINT = {
+
+
 ```
           
       

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.hook-call-freezes-captured-identifier.expect.md

@@ -29,10 +29,16 @@ export const FIXTURE_ENTRYPOINT = {
 ## Error
 
 ```
+Found 1 error:
+Error: This value cannot be modified
+
+Modifying a value previously passed as an argument to a hook is not allowed. Consider moving the modification before calling the hook
+
+error.hook-call-freezes-captured-identifier.ts:13:2
   11 |   });
   12 |
 > 13 |   x.value += count;
-     |   ^ InvalidReact: Updating a value previously passed as an argument to a hook is not allowed. Consider moving the mutation before calling the hook (13:13)
+     |   ^ This value cannot be modified
   14 |   return <Stringify x={x} cb={cb} />;
   15 | }
   16 |

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.hook-call-freezes-captured-memberexpr.expect.md

@@ -29,10 +29,16 @@ export const FIXTURE_ENTRYPOINT = {
 ## Error
 
 ```
+Found 1 error:
+Error: This value cannot be modified
+
+Modifying a value previously passed as an argument to a hook is not allowed. Consider moving the modification before calling the hook
+
+error.hook-call-freezes-captured-memberexpr.ts:13:2
   11 |   });
   12 |
 > 13 |   x.value += count;
-     |   ^ InvalidReact: Updating a value previously passed as an argument to a hook is not allowed. Consider moving the mutation before calling the hook (13:13)
+     |   ^ This value cannot be modified
   14 |   return <Stringify x={x} cb={cb} />;
   15 | }
   16 |

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.hook-property-load-local-hook.expect.md

@@ -23,15 +23,31 @@ export const FIXTURE_ENTRYPOINT = {
 ## Error
 
 ```
+Found 2 errors:
+Error: Hooks may not be referenced as normal values, they must be called. See https://react.dev/reference/rules/react-calls-components-and-hooks#never-pass-around-hooks-as-regular-values
+
+error.hook-property-load-local-hook.ts:7:12
    5 |
    6 | function Foo() {
 >  7 |   let bar = useFoo.useBar;
-     |             ^^^^^^^^^^^^^ InvalidReact: Hooks may not be referenced as normal values, they must be called. See https://react.dev/reference/rules/react-calls-components-and-hooks#never-pass-around-hooks-as-regular-values (7:7)
-
-InvalidReact: Hooks may not be referenced as normal values, they must be called. See https://react.dev/reference/rules/react-calls-components-and-hooks#never-pass-around-hooks-as-regular-values (8:8)
+     |             ^^^^^^^^^^^^^ Hooks may not be referenced as normal values, they must be called. See https://react.dev/reference/rules/react-calls-components-and-hooks#never-pass-around-hooks-as-regular-values
    8 |   return bar();
    9 | }
   10 |
+
+
+Error: Hooks may not be referenced as normal values, they must be called. See https://react.dev/reference/rules/react-calls-components-and-hooks#never-pass-around-hooks-as-regular-values
+
+error.hook-property-load-local-hook.ts:8:9
+   6 | function Foo() {
+   7 |   let bar = useFoo.useBar;
+>  8 |   return bar();
+     |          ^^^ Hooks may not be referenced as normal values, they must be called. See https://react.dev/reference/rules/react-calls-components-and-hooks#never-pass-around-hooks-as-regular-values
+   9 | }
+  10 |
+  11 | export const FIXTURE_ENTRYPOINT = {
+
+
 ```
           
       

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.hook-ref-value.expect.md

@@ -20,15 +20,31 @@ export const FIXTURE_ENTRYPOINT = {
 ## Error
 
 ```
+Found 2 errors:
+Error: Ref values (the `current` property) may not be accessed during render. (https://react.dev/reference/react/useRef)
+
+error.hook-ref-value.ts:5:23
   3 | function Component(props) {
   4 |   const ref = useRef();
 > 5 |   useEffect(() => {}, [ref.current]);
-    |                        ^^^^^^^^^^^ InvalidReact: Ref values (the `current` property) may not be accessed during render. (https://react.dev/reference/react/useRef) (5:5)
-
-InvalidReact: Ref values (the `current` property) may not be accessed during render. (https://react.dev/reference/react/useRef) (5:5)
+    |                        ^^^^^^^^^^^ Ref values (the `current` property) may not be accessed during render. (https://react.dev/reference/react/useRef)
   6 | }
   7 |
   8 | export const FIXTURE_ENTRYPOINT = {
+
+
+Error: Ref values (the `current` property) may not be accessed during render. (https://react.dev/reference/react/useRef)
+
+error.hook-ref-value.ts:5:23
+  3 | function Component(props) {
+  4 |   const ref = useRef();
+> 5 |   useEffect(() => {}, [ref.current]);
+    |                        ^^^^^^^^^^^ Ref values (the `current` property) may not be accessed during render. (https://react.dev/reference/react/useRef)
+  6 | }
+  7 |
+  8 | export const FIXTURE_ENTRYPOINT = {
+
+
 ```
           
       

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-ReactUseMemo-async-callback.expect.md

@@ -15,13 +15,19 @@ function component(a, b) {
 ## Error
 
 ```
+Found 1 error:
+Error: useMemo callbacks may not be async or generator functions
+
+useMemo() callbacks are called once and must synchronously return a value
+
+error.invalid-ReactUseMemo-async-callback.ts:2:24
   1 | function component(a, b) {
 > 2 |   let x = React.useMemo(async () => {
     |                         ^^^^^^^^^^^^^
 > 3 |     await a;
     | ^^^^^^^^^^^^
 > 4 |   }, []);
-    | ^^^^ InvalidReact: useMemo callbacks may not be async or generator functions (2:4)
+    | ^^^^ Async and generator functions are not supported
   5 |   return x;
   6 | }
   7 |

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-access-ref-during-render.expect.md

@@ -15,13 +15,19 @@ function Component(props) {
 ## Error
 
 ```
+Found 1 error:
+Error: Ref values (the `current` property) may not be accessed during render. (https://react.dev/reference/react/useRef)
+
+error.invalid-access-ref-during-render.ts:4:16
   2 | function Component(props) {
   3 |   const ref = useRef(null);
 > 4 |   const value = ref.current;
-    |                 ^^^^^^^^^^^ InvalidReact: Ref values (the `current` property) may not be accessed during render. (https://react.dev/reference/react/useRef) (4:4)
+    |                 ^^^^^^^^^^^ Ref values (the `current` property) may not be accessed during render. (https://react.dev/reference/react/useRef)
   5 |   return value;
   6 | }
   7 |
+
+
 ```
           
       

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-aliased-ref-in-callback-invoked-during-render-.expect.md

@@ -19,12 +19,18 @@ function Component(props) {
 ## Error
 
 ```
+Found 1 error:
+Error: Ref values (the `current` property) may not be accessed during render. (https://react.dev/reference/react/useRef)
+
+error.invalid-aliased-ref-in-callback-invoked-during-render-.ts:9:33
    7 |     return <Foo item={item} current={current} />;
    8 |   };
 >  9 |   return <Items>{props.items.map(item => renderItem(item))}</Items>;
-     |                                  ^^^^^^^^^^^^^^^^^^^^^^^^ InvalidReact: Ref values (the `current` property) may not be accessed during render. (https://react.dev/reference/react/useRef) (9:9)
+     |                                  ^^^^^^^^^^^^^^^^^^^^^^^^ Ref values (the `current` property) may not be accessed during render. (https://react.dev/reference/react/useRef)
   10 | }
   11 |
+
+
 ```
           
       

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-array-push-frozen.expect.md

@@ -15,10 +15,16 @@ function Component(props) {
 ## Error
 
 ```
+Found 1 error:
+Error: This value cannot be modified
+
+Modifying a value used previously in JSX is not allowed. Consider moving the modification before the JSX
+
+error.invalid-array-push-frozen.ts:4:2
   2 |   const x = [];
   3 |   <div>{x}</div>;
 > 4 |   x.push(props.value);
-    |   ^ InvalidReact: Updating a value used previously in JSX is not allowed. Consider moving the mutation before the JSX (4:4)
+    |   ^ This value cannot be modified
   5 |   return x;
   6 | }
   7 |

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-assign-hook-to-local.expect.md

@@ -14,12 +14,18 @@ function Component(props) {
 ## Error
 
 ```
+Found 1 error:
+Error: Hooks may not be referenced as normal values, they must be called. See https://react.dev/reference/rules/react-calls-components-and-hooks#never-pass-around-hooks-as-regular-values
+
+error.invalid-assign-hook-to-local.ts:2:12
   1 | function Component(props) {
 > 2 |   const x = useState;
-    |             ^^^^^^^^ InvalidReact: Hooks may not be referenced as normal values, they must be called. See https://react.dev/reference/rules/react-calls-components-and-hooks#never-pass-around-hooks-as-regular-values (2:2)
+    |             ^^^^^^^^ Hooks may not be referenced as normal values, they must be called. See https://react.dev/reference/rules/react-calls-components-and-hooks#never-pass-around-hooks-as-regular-values
   3 |   const state = x(null);
   4 |   return state[0];
   5 | }
+
+
 ```
           
       

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-computed-store-to-frozen-value.expect.md

@@ -16,10 +16,16 @@ function Component(props) {
 ## Error
 
 ```
+Found 1 error:
+Error: This value cannot be modified
+
+Modifying a value used previously in JSX is not allowed. Consider moving the modification before the JSX
+
+error.invalid-computed-store-to-frozen-value.ts:5:2
   3 |   // freeze
   4 |   <div>{x}</div>;
 > 5 |   x[0] = true;
-    |   ^ InvalidReact: Updating a value used previously in JSX is not allowed. Consider moving the mutation before the JSX (5:5)
+    |   ^ This value cannot be modified
   6 |   return x;
   7 | }
   8 |

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-conditional-call-aliased-hook-import.expect.md

@@ -18,13 +18,19 @@ function Component(props) {
 ## Error
 
 ```
+Found 1 error:
+Error: Hooks must always be called in a consistent order, and may not be called conditionally. See the Rules of Hooks (https://react.dev/warnings/invalid-hook-call-warning)
+
+error.invalid-conditional-call-aliased-hook-import.ts:6:11
   4 |   let data;
   5 |   if (props.cond) {
 > 6 |     data = readFragment();
-    |            ^^^^^^^^^^^^ InvalidReact: Hooks must always be called in a consistent order, and may not be called conditionally. See the Rules of Hooks (https://react.dev/warnings/invalid-hook-call-warning) (6:6)
+    |            ^^^^^^^^^^^^ Hooks must always be called in a consistent order, and may not be called conditionally. See the Rules of Hooks (https://react.dev/warnings/invalid-hook-call-warning)
   7 |   }
   8 |   return data;
   9 | }
+
+
 ```
           
       

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-conditional-call-aliased-react-hook.expect.md

@@ -18,13 +18,19 @@ function Component(props) {
 ## Error
 
 ```
+Found 1 error:
+Error: Hooks must always be called in a consistent order, and may not be called conditionally. See the Rules of Hooks (https://react.dev/warnings/invalid-hook-call-warning)
+
+error.invalid-conditional-call-aliased-react-hook.ts:6:10
   4 |   let s;
   5 |   if (props.cond) {
 > 6 |     [s] = state();
-    |           ^^^^^ InvalidReact: Hooks must always be called in a consistent order, and may not be called conditionally. See the Rules of Hooks (https://react.dev/warnings/invalid-hook-call-warning) (6:6)
+    |           ^^^^^ Hooks must always be called in a consistent order, and may not be called conditionally. See the Rules of Hooks (https://react.dev/warnings/invalid-hook-call-warning)
   7 |   }
   8 |   return s;
   9 | }
+
+
 ```
           
       

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-conditional-call-non-hook-imported-as-hook.expect.md

@@ -18,13 +18,19 @@ function Component(props) {
 ## Error
 
 ```
+Found 1 error:
+Error: Hooks must always be called in a consistent order, and may not be called conditionally. See the Rules of Hooks (https://react.dev/warnings/invalid-hook-call-warning)
+
+error.invalid-conditional-call-non-hook-imported-as-hook.ts:6:11
   4 |   let data;
   5 |   if (props.cond) {
 > 6 |     data = useArray();
-    |            ^^^^^^^^ InvalidReact: Hooks must always be called in a consistent order, and may not be called conditionally. See the Rules of Hooks (https://react.dev/warnings/invalid-hook-call-warning) (6:6)
+    |            ^^^^^^^^ Hooks must always be called in a consistent order, and may not be called conditionally. See the Rules of Hooks (https://react.dev/warnings/invalid-hook-call-warning)
   7 |   }
   8 |   return data;
   9 | }
+
+
 ```
           
       

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-conditional-setState-in-useMemo.expect.md

@@ -22,15 +22,31 @@ function Component({item, cond}) {
 ## Error
 
 ```
+Found 2 errors:
+Error: Calling setState from useMemo may trigger an infinite loop
+
+Each time the memo callback is evaluated it will change state. This can cause a memoization dependency to change, running the memo function again and causing an infinite loop. Instead of setting state in useMemo(), prefer deriving the value during render. (https://react.dev/reference/react/useState)
+
+error.invalid-conditional-setState-in-useMemo.ts:7:6
    5 |   useMemo(() => {
    6 |     if (cond) {
 >  7 |       setPrevItem(item);
-     |       ^^^^^^^^^^^ InvalidReact: Calling setState from useMemo may trigger an infinite loop. (https://react.dev/reference/react/useState) (7:7)
-
-InvalidReact: Calling setState from useMemo may trigger an infinite loop. (https://react.dev/reference/react/useState) (8:8)
+     |       ^^^^^^^^^^^ Found setState() within useMemo()
    8 |       setState(0);
    9 |     }
   10 |   }, [cond, key, init]);
+Error: Calling setState from useMemo may trigger an infinite loop
+
+Each time the memo callback is evaluated it will change state. This can cause a memoization dependency to change, running the memo function again and causing an infinite loop. Instead of setting state in useMemo(), prefer deriving the value during render. (https://react.dev/reference/react/useState)
+
+error.invalid-conditional-setState-in-useMemo.ts:8:6
+   6 |     if (cond) {
+   7 |       setPrevItem(item);
+>  8 |       setState(0);
+     |       ^^^^^^^^ Found setState() within useMemo()
+   9 |     }
+  10 |   }, [cond, key, init]);
+  11 |
 ```
           
       

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-delete-computed-property-of-frozen-value.expect.md

@@ -16,10 +16,16 @@ function Component(props) {
 ## Error
 
 ```
+Found 1 error:
+Error: This value cannot be modified
+
+Modifying a value used previously in JSX is not allowed. Consider moving the modification before the JSX
+
+error.invalid-delete-computed-property-of-frozen-value.ts:5:9
   3 |   // freeze
   4 |   <div>{x}</div>;
 > 5 |   delete x[y];
-    |          ^ InvalidReact: Updating a value used previously in JSX is not allowed. Consider moving the mutation before the JSX (5:5)
+    |          ^ This value cannot be modified
   6 |   return x;
   7 | }
   8 |

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-delete-property-of-frozen-value.expect.md

@@ -16,10 +16,16 @@ function Component(props) {
 ## Error
 
 ```
+Found 1 error:
+Error: This value cannot be modified
+
+Modifying a value used previously in JSX is not allowed. Consider moving the modification before the JSX
+
+error.invalid-delete-property-of-frozen-value.ts:5:9
   3 |   // freeze
   4 |   <div>{x}</div>;
 > 5 |   delete x.y;
-    |          ^ InvalidReact: Updating a value used previously in JSX is not allowed. Consider moving the mutation before the JSX (5:5)
+    |          ^ This value cannot be modified
   6 |   return x;
   7 | }
   8 |

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-destructure-assignment-to-global.expect.md

@@ -13,9 +13,15 @@ function useFoo(props) {
 ## Error
 
 ```
+Found 1 error:
+Error: Cannot reassign variables declared outside of the component/hook
+
+Reassigning a variable declared outside of the component/hook is a form of side effect, which can cause unpredictable behavior depending on when the component happens to re-render. If this variable is used in rendering, use useState instead. Otherwise, consider updating it in an effect (https://react.dev/reference/rules/components-and-hooks-must-be-pure#side-effects-must-run-outside-of-render)
+
+error.invalid-destructure-assignment-to-global.ts:2:3
   1 | function useFoo(props) {
 > 2 |   [x] = props;
-    |    ^ InvalidReact: Unexpected reassignment of a variable which was defined outside of the component. Components and hooks should be pure and side-effect free, but variable reassignment is a form of side-effect. If this variable is used in rendering, use useState instead. (https://react.dev/reference/rules/components-and-hooks-must-be-pure#side-effects-must-run-outside-of-render) (2:2)
+    |    ^ Cannot reassign variable
   3 |   return {x};
   4 | }
   5 |

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-destructure-to-local-global-variables.expect.md

@@ -15,10 +15,16 @@ function Component(props) {
 ## Error
 
 ```
+Found 1 error:
+Error: Cannot reassign variables declared outside of the component/hook
+
+Reassigning a variable declared outside of the component/hook is a form of side effect, which can cause unpredictable behavior depending on when the component happens to re-render. If this variable is used in rendering, use useState instead. Otherwise, consider updating it in an effect (https://react.dev/reference/rules/components-and-hooks-must-be-pure#side-effects-must-run-outside-of-render)
+
+error.invalid-destructure-to-local-global-variables.ts:3:6
   1 | function Component(props) {
   2 |   let a;
 > 3 |   [a, b] = props.value;
-    |       ^ InvalidReact: Unexpected reassignment of a variable which was defined outside of the component. Components and hooks should be pure and side-effect free, but variable reassignment is a form of side-effect. If this variable is used in rendering, use useState instead. (https://react.dev/reference/rules/components-and-hooks-must-be-pure#side-effects-must-run-outside-of-render) (3:3)
+    |       ^ Cannot reassign variable
   4 |
   5 |   return [a, b];
   6 | }

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-disallow-mutating-ref-in-render.expect.md

@@ -16,13 +16,19 @@ function Component() {
 ## Error
 
 ```
+Found 1 error:
+Error: Ref values (the `current` property) may not be accessed during render. (https://react.dev/reference/react/useRef)
+
+error.invalid-disallow-mutating-ref-in-render.ts:4:2
   2 | function Component() {
   3 |   const ref = useRef(null);
 > 4 |   ref.current = false;
-    |   ^^^^^^^^^^^ InvalidReact: Ref values (the `current` property) may not be accessed during render. (https://react.dev/reference/react/useRef) (4:4)
+    |   ^^^^^^^^^^^ Ref values (the `current` property) may not be accessed during render. (https://react.dev/reference/react/useRef)
   5 |
   6 |   return <button ref={ref} />;
   7 | }
+
+
 ```
           
       

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-disallow-mutating-refs-in-render-transitive.expect.md

@@ -21,15 +21,31 @@ function Component() {
 ## Error
 
 ```
+Found 2 errors:
+Error: This function accesses a ref value (the `current` property), which may not be accessed during render. (https://react.dev/reference/react/useRef)
+
+error.invalid-disallow-mutating-refs-in-render-transitive.ts:9:2
    7 |   };
    8 |   const changeRef = setRef;
 >  9 |   changeRef();
-     |   ^^^^^^^^^ InvalidReact: This function accesses a ref value (the `current` property), which may not be accessed during render. (https://react.dev/reference/react/useRef) (9:9)
-
-InvalidReact: Ref values (the `current` property) may not be accessed during render. (https://react.dev/reference/react/useRef) (9:9)
+     |   ^^^^^^^^^ This function accesses a ref value (the `current` property), which may not be accessed during render. (https://react.dev/reference/react/useRef)
   10 |
   11 |   return <button ref={ref} />;
   12 | }
+
+
+Error: Ref values (the `current` property) may not be accessed during render. (https://react.dev/reference/react/useRef)
+
+error.invalid-disallow-mutating-refs-in-render-transitive.ts:9:2
+   7 |   };
+   8 |   const changeRef = setRef;
+>  9 |   changeRef();
+     |   ^^^^^^^^^ Ref values (the `current` property) may not be accessed during render. (https://react.dev/reference/react/useRef)
+  10 |
+  11 |   return <button ref={ref} />;
+  12 | }
+
+
 ```
           
       

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-eval-unsupported.expect.md

@@ -13,12 +13,20 @@ function Component(props) {
 ## Error
 
 ```
+Found 1 error:
+Error: The 'eval' function is not supported
+
+Eval is an anti-pattern in JavaScript, and the code executed cannot be evaluated by React Compiler.
+
+error.invalid-eval-unsupported.ts:2:2
   1 | function Component(props) {
 > 2 |   eval('props.x = true');
-    |   ^^^^ UnsupportedJS: The 'eval' function is not supported. Eval is an anti-pattern in JavaScript, and the code executed cannot be evaluated by React Compiler (2:2)
+    |   ^^^^ The 'eval' function is not supported
   3 |   return <div />;
   4 | }
   5 |
+
+
 ```
           
       

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-function-expression-mutates-immutable-value.expect.md

@@ -18,10 +18,16 @@ function Component(props) {
 ## Error
 
 ```
+Found 1 error:
+Error: This value cannot be modified
+
+Modifying a value returned from 'useState()', which should not be modified directly. Use the setter function to update instead
+
+error.invalid-function-expression-mutates-immutable-value.ts:5:4
   3 |   const onChange = e => {
   4 |     // INVALID! should use copy-on-write and pass the new value
 > 5 |     x.value = e.target.value;
-    |     ^ InvalidReact: Mutating a value returned from 'useState()', which should not be mutated. Use the setter function to update instead. Found mutation of `x` (5:5)
+    |     ^ `x` cannot be modified
   6 |     setX(x);
   7 |   };
   8 |   return <input value={x.value} onChange={onChange} />;

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-global-reassignment-indirect.expect.md

@@ -35,10 +35,16 @@ export const FIXTURE_ENTRYPOINT = {
 ## Error
 
 ```
+Found 1 error:
+Error: Cannot reassign variables declared outside of the component/hook
+
+Reassigning a variable declared outside of the component/hook is a form of side effect, which can cause unpredictable behavior depending on when the component happens to re-render. If this variable is used in rendering, use useState instead. Otherwise, consider updating it in an effect (https://react.dev/reference/rules/components-and-hooks-must-be-pure#side-effects-must-run-outside-of-render)
+
+error.invalid-global-reassignment-indirect.ts:9:4
    7 |
    8 |   const setGlobal = () => {
 >  9 |     someGlobal = true;
-     |     ^^^^^^^^^^ InvalidReact: Unexpected reassignment of a variable which was defined outside of the component. Components and hooks should be pure and side-effect free, but variable reassignment is a form of side-effect. If this variable is used in rendering, use useState instead. (https://react.dev/reference/rules/components-and-hooks-must-be-pure#side-effects-must-run-outside-of-render) (9:9)
+     |     ^^^^^^^^^^ Cannot reassign variable
   10 |   };
   11 |   const indirectSetGlobal = () => {
   12 |     setGlobal();

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-hoisting-setstate.expect.md

@@ -38,15 +38,28 @@ export const FIXTURE_ENTRYPOINT = {
 ## Error
 
 ```
+Found 1 error:
+Error: Cannot access variable before it is declared
+
+Variable `setState` is accessed before it is declared, which prevents the earlier access from updating when this value changes over time
+
+error.invalid-hoisting-setstate.ts:19:18
   17 |    * $2 = Function context=setState
   18 |    */
 > 19 |   useEffect(() => setState(2), []);
-     |                   ^^^^^^^^ InvalidReact: This variable is accessed before it is declared, which may prevent it from updating as the assigned value changes over time. Variable `setState` is accessed before it is declared (19:19)
-
-InvalidReact: This variable is accessed before it is declared, which prevents the earlier access from updating when this value changes over time. Variable `setState` is accessed before it is declared (21:21)
+     |                   ^^^^^^^^ Variable accessed before it is declared
   20 |
   21 |   const [state, setState] = useState(0);
   22 |   return <Stringify state={state} />;
+
+error.invalid-hoisting-setstate.ts:21:16
+  19 |   useEffect(() => setState(2), []);
+  20 |
+> 21 |   const [state, setState] = useState(0);
+     |                 ^^^^^^^^ The variable is declared here
+  22 |   return <Stringify state={state} />;
+  23 | }
+  24 |
 ```
           
       

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-hook-function-argument-mutates-local-variable.expect.md

@@ -17,6 +17,12 @@ function useFoo() {
 ## Error
 
 ```
+Found 1 error:
+Error: Cannot modify local variables after render completes
+
+This argument is a function which may reassign or mutate local variables after render, which can cause inconsistent behavior on subsequent renders. Consider using state instead
+
+error.invalid-hook-function-argument-mutates-local-variable.ts:5:10
   3 | function useFoo() {
   4 |   const cache = new Map();
 > 5 |   useHook(() => {
@@ -24,9 +30,16 @@ function useFoo() {
 > 6 |     cache.set('key', 'value');
     | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 > 7 |   });
-    | ^^^^ InvalidReact: This argument is a function which may reassign or mutate local variables after render, which can cause inconsistent behavior on subsequent renders. Consider using state instead (5:7)
+    | ^^^^ This function may (indirectly) reassign or modify local variables after render
+  8 | }
+  9 |
 
-InvalidReact: The function modifies a local variable here (6:6)
+error.invalid-hook-function-argument-mutates-local-variable.ts:6:4
+  4 |   const cache = new Map();
+  5 |   useHook(() => {
+> 6 |     cache.set('key', 'value');
+    |     ^^^^^ This modifies a local variable
+  7 |   });
   8 | }
   9 |
 ```

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-impure-functions-in-render.expect.md

@@ -17,17 +17,43 @@ function Component() {
 ## Error
 
 ```
+Found 3 errors:
+Error: Cannot call impure function during render
+
+`Date.now` is an impure function. Calling an impure function can produce unstable results that update unpredictably when the component happens to re-render. (https://react.dev/reference/rules/components-and-hooks-must-be-pure#components-and-hooks-must-be-idempotent)
+
+error.invalid-impure-functions-in-render.ts:4:15
   2 |
   3 | function Component() {
 > 4 |   const date = Date.now();
-    |                ^^^^^^^^^^ InvalidReact: Calling an impure function can produce unstable results. (https://react.dev/reference/rules/components-and-hooks-must-be-pure#components-and-hooks-must-be-idempotent). `Date.now` is an impure function whose results may change on every call (4:4)
-
-InvalidReact: Calling an impure function can produce unstable results. (https://react.dev/reference/rules/components-and-hooks-must-be-pure#components-and-hooks-must-be-idempotent). `performance.now` is an impure function whose results may change on every call (5:5)
-
-InvalidReact: Calling an impure function can produce unstable results. (https://react.dev/reference/rules/components-and-hooks-must-be-pure#components-and-hooks-must-be-idempotent). `Math.random` is an impure function whose results may change on every call (6:6)
+    |                ^^^^^^^^^^ Cannot call impure function
   5 |   const now = performance.now();
   6 |   const rand = Math.random();
   7 |   return <Foo date={date} now={now} rand={rand} />;
+Error: Cannot call impure function during render
+
+`performance.now` is an impure function. Calling an impure function can produce unstable results that update unpredictably when the component happens to re-render. (https://react.dev/reference/rules/components-and-hooks-must-be-pure#components-and-hooks-must-be-idempotent)
+
+error.invalid-impure-functions-in-render.ts:5:14
+  3 | function Component() {
+  4 |   const date = Date.now();
+> 5 |   const now = performance.now();
+    |               ^^^^^^^^^^^^^^^^^ Cannot call impure function
+  6 |   const rand = Math.random();
+  7 |   return <Foo date={date} now={now} rand={rand} />;
+  8 | }
+Error: Cannot call impure function during render
+
+`Math.random` is an impure function. Calling an impure function can produce unstable results that update unpredictably when the component happens to re-render. (https://react.dev/reference/rules/components-and-hooks-must-be-pure#components-and-hooks-must-be-idempotent)
+
+error.invalid-impure-functions-in-render.ts:6:15
+  4 |   const date = Date.now();
+  5 |   const now = performance.now();
+> 6 |   const rand = Math.random();
+    |                ^^^^^^^^^^^^^ Cannot call impure function
+  7 |   return <Foo date={date} now={now} rand={rand} />;
+  8 | }
+  9 |
 ```
           
       

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-jsx-captures-context-variable.expect.md

@@ -50,10 +50,16 @@ export const FIXTURE_ENTRYPOINT = {
 ## Error
 
 ```
+Found 1 error:
+Error: This value cannot be modified
+
+Modifying a value used previously in JSX is not allowed. Consider moving the modification before the JSX
+
+error.invalid-jsx-captures-context-variable.ts:22:2
   20 |     />
   21 |   );
 > 22 |   i = i + 1;
-     |   ^ InvalidReact: Updating a value used previously in JSX is not allowed. Consider moving the mutation before the JSX. Found mutation of `i` (22:22)
+     |   ^ `i` cannot be modified
   23 |   items.push(
   24 |     <Stringify
   25 |       key={i}

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-mutate-after-aliased-freeze.expect.md

@@ -25,10 +25,16 @@ function Component(props) {
 ## Error
 
 ```
+Found 1 error:
+Error: This value cannot be modified
+
+Modifying a value used previously in JSX is not allowed. Consider moving the modification before the JSX
+
+error.invalid-mutate-after-aliased-freeze.ts:13:2
   11 |   // y is MaybeFrozen at this point, since it may alias to x
   12 |   // (which is the above line freezes)
 > 13 |   y.push(props.p2);
-     |   ^ InvalidReact: Updating a value used previously in JSX is not allowed. Consider moving the mutation before the JSX (13:13)
+     |   ^ This value cannot be modified
   14 |
   15 |   return <Component x={x} y={y} />;
   16 | }

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-mutate-after-freeze.expect.md

@@ -19,10 +19,16 @@ function Component(props) {
 ## Error
 
 ```
+Found 1 error:
+Error: This value cannot be modified
+
+Modifying a value used previously in JSX is not allowed. Consider moving the modification before the JSX
+
+error.invalid-mutate-after-freeze.ts:7:2
    5 |
    6 |   // x is Frozen at this point
 >  7 |   x.push(props.p2);
-     |   ^ InvalidReact: Updating a value used previously in JSX is not allowed. Consider moving the mutation before the JSX (7:7)
+     |   ^ This value cannot be modified
    8 |
    9 |   return <div>{_}</div>;
   10 | }

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-mutate-context-in-callback.expect.md

@@ -24,10 +24,16 @@ function Component(props) {
 ## Error
 
 ```
+Found 1 error:
+Error: This value cannot be modified
+
+Modifying a value returned from 'useContext()' is not allowed.
+
+error.invalid-mutate-context-in-callback.ts:12:4
   10 |   // independently
   11 |   const onClick = () => {
 > 12 |     FooContext.current = true;
-     |     ^^^^^^^^^^ InvalidReact: Mutating a value returned from 'useContext()', which should not be mutated. Found mutation of `FooContext` (12:12)
+     |     ^^^^^^^^^^ `FooContext` cannot be modified
   13 |   };
   14 |   return <div onClick={onClick} />;
   15 | }

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-mutate-context.expect.md

@@ -14,10 +14,16 @@ function Component(props) {
 ## Error
 
 ```
+Found 1 error:
+Error: This value cannot be modified
+
+Modifying a value returned from 'useContext()' is not allowed.
+
+error.invalid-mutate-context.ts:3:2
   1 | function Component(props) {
   2 |   const context = useContext(FooContext);
 > 3 |   context.value = props.value;
-    |   ^^^^^^^ InvalidReact: Mutating a value returned from 'useContext()', which should not be mutated (3:3)
+    |   ^^^^^^^ This value cannot be modified
   4 |   return context.value;
   5 | }
   6 |

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-mutate-props-in-effect-fixpoint.expect.md

@@ -25,10 +25,16 @@ function Component(props) {
 ## Error
 
 ```
+Found 1 error:
+Error: This value cannot be modified
+
+Modifying component props or hook arguments is not allowed. Consider using a local variable instead
+
+error.invalid-mutate-props-in-effect-fixpoint.ts:10:4
    8 |   let y = x;
    9 |   let mutateProps = () => {
 > 10 |     y.foo = true;
-     |     ^ InvalidReact: Mutating component props or hook arguments is not allowed. Consider using a local variable instead. Found mutation of `y` (10:10)
+     |     ^ `y` cannot be modified
   11 |   };
   12 |   let mutatePropsIndirect = () => {
   13 |     mutateProps();

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-mutate-props-via-for-of-iterator.expect.md

@@ -17,10 +17,16 @@ function Component(props) {
 ## Error
 
 ```
+Found 1 error:
+Error: This value cannot be modified
+
+Modifying component props or hook arguments is not allowed. Consider using a local variable instead
+
+error.invalid-mutate-props-via-for-of-iterator.ts:4:4
   2 |   const items = [];
   3 |   for (const x of props.items) {
 > 4 |     x.modified = true;
-    |     ^ InvalidReact: Mutating component props or hook arguments is not allowed. Consider using a local variable instead (4:4)
+    |     ^ This value cannot be modified
   5 |     items.push(x);
   6 |   }
   7 |   return items;

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-mutation-in-closure.expect.md

@@ -16,10 +16,16 @@ function useInvalidMutation(options) {
 ## Error
 
 ```
+Found 1 error:
+Error: This value cannot be modified
+
+Modifying component props or hook arguments is not allowed. Consider using a local variable instead
+
+error.invalid-mutation-in-closure.ts:4:4
   2 |   function test() {
   3 |     foo(options.foo); // error should not point on this line
 > 4 |     options.foo = 'bar';
-    |     ^^^^^^^ InvalidReact: Mutating component props or hook arguments is not allowed. Consider using a local variable instead. Found mutation of `options` (4:4)
+    |     ^^^^^^^ `options` cannot be modified
   5 |   }
   6 |   return test;
   7 | }

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-mutation-of-possible-props-phi-indirect.expect.md

@@ -19,10 +19,16 @@ function Component(props) {
 ## Error
 
 ```
+Found 1 error:
+Error: This value cannot be modified
+
+Modifying a variable defined outside a component or hook is not allowed. Consider using an effect
+
+error.invalid-mutation-of-possible-props-phi-indirect.ts:4:4
   2 |   let x = cond ? someGlobal : props.foo;
   3 |   const mutatePhiThatCouldBeProps = () => {
 > 4 |     x.y = true;
-    |     ^ InvalidReact: Writing to a variable defined outside a component or hook is not allowed. Consider using an effect. Found mutation of `x` (4:4)
+    |     ^ `x` cannot be modified
   5 |   };
   6 |   const indirectMutateProps = () => {
   7 |     mutatePhiThatCouldBeProps();

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-nested-function-reassign-local-variable-in-effect.expect.md

@@ -46,10 +46,16 @@ function Component() {
 ## Error
 
 ```
+Found 1 error:
+Error: Cannot reassign a variable after render completes
+
+Reassigning variable `local` after render has completed can cause inconsistent behavior on subsequent renders. Consider using state instead
+
+error.invalid-nested-function-reassign-local-variable-in-effect.ts:7:6
    5 |     // Create the reassignment function inside another function, then return it
    6 |     const reassignLocal = newValue => {
 >  7 |       local = newValue;
-     |       ^^^^^ InvalidReact: Reassigning a variable after render has completed can cause inconsistent behavior on subsequent renders. Consider using state instead. Variable `local` cannot be reassigned after render (7:7)
+     |       ^^^^^ Cannot reassign variable after render completes
    8 |     };
    9 |     return reassignLocal;
   10 |   };

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-non-imported-reanimated-shared-value-writes.expect.md

@@ -24,10 +24,16 @@ function SomeComponent() {
 ## Error
 
 ```
+Found 1 error:
+Error: This value cannot be modified
+
+Modifying a value returned from a hook is not allowed. Consider moving the modification into the hook where the value is constructed
+
+error.invalid-non-imported-reanimated-shared-value-writes.ts:11:22
    9 |   return (
   10 |     <Button
 > 11 |       onPress={() => (sharedVal.value = Math.random())}
-     |                       ^^^^^^^^^ InvalidReact: Updating a value returned from a hook is not allowed. Consider moving the mutation into the hook where the value is constructed. Found mutation of `sharedVal` (11:11)
+     |                       ^^^^^^^^^ `sharedVal` cannot be modified
   12 |       title="Randomize"
   13 |     />
   14 |   );

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-optional-member-expression-as-memo-dep-non-optional-in-body.expect.md

@@ -18,6 +18,12 @@ function Component(props) {
 ## Error
 
 ```
+Found 1 error:
+Memoization: Compilation skipped because existing memoization could not be preserved
+
+React Compiler has skipped optimizing this component because the existing manual memoization could not be preserved. The inferred dependencies did not match the manually specified dependencies, which could cause the value to change more or less frequently than expected. The inferred dependency was `props.items.edges.nodes`, but the source dependencies were [props.items?.edges?.nodes]. Inferred different dependency than source.
+
+error.invalid-optional-member-expression-as-memo-dep-non-optional-in-body.ts:3:23
    1 | // @validatePreserveExistingMemoizationGuarantees
    2 | function Component(props) {
 >  3 |   const data = useMemo(() => {
@@ -29,7 +35,7 @@ function Component(props) {
 >  6 |     // deps are optional
      | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 >  7 |   }, [props.items?.edges?.nodes]);
-     | ^^^^ CannotPreserveMemoization: React Compiler has skipped optimizing this component because the existing manual memoization could not be preserved. The inferred dependencies did not match the manually specified dependencies, which could cause the value to change more or less frequently than expected. The inferred dependency was `props.items.edges.nodes`, but the source dependencies were [props.items?.edges?.nodes]. Inferred different dependency than source (3:7)
+     | ^^^^ Could not preserve existing manual memoization
    8 |   return <Foo data={data} />;
    9 | }
   10 |

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-pass-hook-as-call-arg.expect.md

@@ -12,11 +12,17 @@ function Component(props) {
 ## Error
 
 ```
+Found 1 error:
+Error: Hooks may not be referenced as normal values, they must be called. See https://react.dev/reference/rules/react-calls-components-and-hooks#never-pass-around-hooks-as-regular-values
+
+error.invalid-pass-hook-as-call-arg.ts:2:13
   1 | function Component(props) {
 > 2 |   return foo(useFoo);
-    |              ^^^^^^ InvalidReact: Hooks may not be referenced as normal values, they must be called. See https://react.dev/reference/rules/react-calls-components-and-hooks#never-pass-around-hooks-as-regular-values (2:2)
+    |              ^^^^^^ Hooks may not be referenced as normal values, they must be called. See https://react.dev/reference/rules/react-calls-components-and-hooks#never-pass-around-hooks-as-regular-values
   3 | }
   4 |
+
+
 ```
           
       

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-pass-hook-as-prop.expect.md

@@ -12,11 +12,17 @@ function Component(props) {
 ## Error
 
 ```
+Found 1 error:
+Error: Hooks may not be referenced as normal values, they must be called. See https://react.dev/reference/rules/react-calls-components-and-hooks#never-pass-around-hooks-as-regular-values
+
+error.invalid-pass-hook-as-prop.ts:2:21
   1 | function Component(props) {
 > 2 |   return <Child foo={useFoo} />;
-    |                      ^^^^^^ InvalidReact: Hooks may not be referenced as normal values, they must be called. See https://react.dev/reference/rules/react-calls-components-and-hooks#never-pass-around-hooks-as-regular-values (2:2)
+    |                      ^^^^^^ Hooks may not be referenced as normal values, they must be called. See https://react.dev/reference/rules/react-calls-components-and-hooks#never-pass-around-hooks-as-regular-values
   3 | }
   4 |
+
+
 ```
           
       

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-pass-mutable-function-as-prop.expect.md

@@ -17,14 +17,27 @@ function Component() {
 ## Error
 
 ```
+Found 1 error:
+Error: Cannot modify local variables after render completes
+
+This argument is a function which may reassign or mutate local variables after render, which can cause inconsistent behavior on subsequent renders. Consider using state instead
+
+error.invalid-pass-mutable-function-as-prop.ts:7:18
   5 |     cache.set('key', 'value');
   6 |   };
 > 7 |   return <Foo fn={fn} />;
-    |                   ^^ InvalidReact: This argument is a function which may reassign or mutate local variables after render, which can cause inconsistent behavior on subsequent renders. Consider using state instead (7:7)
-
-InvalidReact: The function modifies a local variable here (5:5)
+    |                   ^^ This function may (indirectly) reassign or modify local variables after render
   8 | }
   9 |
+
+error.invalid-pass-mutable-function-as-prop.ts:5:4
+  3 |   const cache = new Map();
+  4 |   const fn = () => {
+> 5 |     cache.set('key', 'value');
+    |     ^^^^^ This modifies a local variable
+  6 |   };
+  7 |   return <Foo fn={fn} />;
+  8 | }
 ```
           
       

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-pass-ref-to-function.expect.md

@@ -15,13 +15,19 @@ function Component(props) {
 ## Error
 
 ```
+Found 1 error:
+Error: Ref values (the `current` property) may not be accessed during render. (https://react.dev/reference/react/useRef)
+
+error.invalid-pass-ref-to-function.ts:4:16
   2 | function Component(props) {
   3 |   const ref = useRef(null);
 > 4 |   const x = foo(ref);
-    |                 ^^^ InvalidReact: Ref values (the `current` property) may not be accessed during render. (https://react.dev/reference/react/useRef) (4:4)
+    |                 ^^^ Ref values (the `current` property) may not be accessed during render. (https://react.dev/reference/react/useRef)
   5 |   return x.current;
   6 | }
   7 |
+
+
 ```
           
       

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-prop-mutation-indirect.expect.md

@@ -18,10 +18,16 @@ function Component(props) {
 ## Error
 
 ```
+Found 1 error:
+Error: This value cannot be modified
+
+Modifying component props or hook arguments is not allowed. Consider using a local variable instead
+
+error.invalid-prop-mutation-indirect.ts:3:4
   1 | function Component(props) {
   2 |   const f = () => {
 > 3 |     props.value = true;
-    |     ^^^^^ InvalidReact: Mutating component props or hook arguments is not allowed. Consider using a local variable instead. Found mutation of `props` (3:3)
+    |     ^^^^^ `props` cannot be modified
   4 |   };
   5 |   const g = () => {
   6 |     f();

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-property-store-to-frozen-value.expect.md

@@ -16,10 +16,16 @@ function Component(props) {
 ## Error
 
 ```
+Found 1 error:
+Error: This value cannot be modified
+
+Modifying a value used previously in JSX is not allowed. Consider moving the modification before the JSX
+
+error.invalid-property-store-to-frozen-value.ts:5:2
   3 |   // freeze
   4 |   <div>{x}</div>;
 > 5 |   x.y = true;
-    |   ^ InvalidReact: Updating a value used previously in JSX is not allowed. Consider moving the mutation before the JSX (5:5)
+    |   ^ This value cannot be modified
   6 |   return x;
   7 | }
   8 |

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-props-mutation-in-effect-indirect.expect.md

@@ -18,10 +18,16 @@ function Component(props) {
 ## Error
 
 ```
+Found 1 error:
+Error: This value cannot be modified
+
+Modifying component props or hook arguments is not allowed. Consider using a local variable instead
+
+error.invalid-props-mutation-in-effect-indirect.ts:3:4
   1 | function Component(props) {
   2 |   const mutateProps = () => {
 > 3 |     props.value = true;
-    |     ^^^^^ InvalidReact: Mutating component props or hook arguments is not allowed. Consider using a local variable instead. Found mutation of `props` (3:3)
+    |     ^^^^^ `props` cannot be modified
   4 |   };
   5 |   const indirectMutateProps = () => {
   6 |     mutateProps();

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-read-ref-prop-in-render-destructure.expect.md

@@ -14,13 +14,19 @@ function Component({ref}) {
 ## Error
 
 ```
+Found 1 error:
+Error: Ref values (the `current` property) may not be accessed during render. (https://react.dev/reference/react/useRef)
+
+error.invalid-read-ref-prop-in-render-destructure.ts:3:16
   1 | // @validateRefAccessDuringRender @compilationMode:"infer"
   2 | function Component({ref}) {
 > 3 |   const value = ref.current;
-    |                 ^^^^^^^^^^^ InvalidReact: Ref values (the `current` property) may not be accessed during render. (https://react.dev/reference/react/useRef) (3:3)
+    |                 ^^^^^^^^^^^ Ref values (the `current` property) may not be accessed during render. (https://react.dev/reference/react/useRef)
   4 |   return <div>{value}</div>;
   5 | }
   6 |
+
+
 ```
           
       

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-read-ref-prop-in-render-property-load.expect.md

@@ -14,13 +14,19 @@ function Component(props) {
 ## Error
 
 ```
+Found 1 error:
+Error: Ref values (the `current` property) may not be accessed during render. (https://react.dev/reference/react/useRef)
+
+error.invalid-read-ref-prop-in-render-property-load.ts:3:16
   1 | // @validateRefAccessDuringRender @compilationMode:"infer"
   2 | function Component(props) {
 > 3 |   const value = props.ref.current;
-    |                 ^^^^^^^^^^^^^^^^^ InvalidReact: Ref values (the `current` property) may not be accessed during render. (https://react.dev/reference/react/useRef) (3:3)
+    |                 ^^^^^^^^^^^^^^^^^ Ref values (the `current` property) may not be accessed during render. (https://react.dev/reference/react/useRef)
   4 |   return <div>{value}</div>;
   5 | }
   6 |
+
+
 ```
           
       

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

@@ -13,12 +13,20 @@ function Component() {
 ## Error
 
 ```
+Found 1 error:
+Error: Cannot reassign a `const` variable
+
+`x` is declared as const.
+
+error.invalid-reassign-const.ts:3:2
   1 | function Component() {
   2 |   const x = 0;
 > 3 |   x = 1;
-    |   ^ InvalidJS: Cannot reassign a `const` variable. `x` is declared as const (3:3)
+    |   ^ Cannot reassign a `const` variable
   4 | }
   5 |
+
+
 ```
           
       

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/error.invalid-reassign-local-in-hook-return-value.expect.md

@@ -15,10 +15,16 @@ function useFoo() {
 ## Error
 
 ```
+Found 1 error:
+Error: Cannot reassign a variable after render completes
+
+Reassigning variable `x` after render has completed can cause inconsistent behavior on subsequent renders. Consider using state instead
+
+error.invalid-reassign-local-in-hook-return-value.ts:4:4
   2 |   let x = 0;
   3 |   return value => {
 > 4 |     x = value;
-    |     ^ InvalidReact: Reassigning a variable after render has completed can cause inconsistent behavior on subsequent renders. Consider using state instead. Variable `x` cannot be reassigned after render (4:4)
+    |     ^ Cannot reassign variable after render completes
   5 |   };
   6 | }
   7 |

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

@@ -25,13 +25,21 @@ function Component() {
 ## Error
 
 ```
+Found 1 error:
+Error: Reassigning a variable in an async function can cause inconsistent behavior on subsequent renders. Consider using state instead
+
+Variable `value` cannot be reassigned after render.
+
+error.invalid-reassign-local-variable-in-async-callback.ts:8:6
    6 |       // after render, so this should error regardless of where this ends up
    7 |       // getting called
 >  8 |       value = result;
-     |       ^^^^^ InvalidReact: Reassigning a variable in an async function can cause inconsistent behavior on subsequent renders. Consider using state instead. Variable `value` cannot be reassigned after render (8:8)
+     |       ^^^^^ Reassigning a variable in an async function can cause inconsistent behavior on subsequent renders. Consider using state instead
    9 |     });
   10 |   };
   11 |
+
+
 ```
           
       

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

@@ -47,10 +47,16 @@ function Component() {
 ## Error
 
 ```
+Found 1 error:
+Error: Cannot reassign a variable after render completes
+
+Reassigning variable `local` after render has completed can cause inconsistent behavior on subsequent renders. Consider using state instead
+
+error.invalid-reassign-local-variable-in-effect.ts:7:4
    5 |
    6 |   const reassignLocal = newValue => {
 >  7 |     local = newValue;
-     |     ^^^^^ InvalidReact: Reassigning a variable after render has completed can cause inconsistent behavior on subsequent renders. Consider using state instead. Variable `local` cannot be reassigned after render (7:7)
+     |     ^^^^^ Cannot reassign variable after render completes
    8 |   };
    9 |
   10 |   const onMount = newValue => {

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

@@ -48,10 +48,16 @@ function Component() {
 ## Error
 
 ```
+Found 1 error:
+Error: Cannot reassign a variable after render completes
+
+Reassigning variable `local` after render has completed can cause inconsistent behavior on subsequent renders. Consider using state instead
+
+error.invalid-reassign-local-variable-in-hook-argument.ts:8:4
    6 |
    7 |   const reassignLocal = newValue => {
 >  8 |     local = newValue;
-     |     ^^^^^ InvalidReact: Reassigning a variable after render has completed can cause inconsistent behavior on subsequent renders. Consider using state instead. Variable `local` cannot be reassigned after render (8:8)
+     |     ^^^^^ Cannot reassign variable after render completes
    9 |   };
   10 |
   11 |   const callback = newValue => {