[pull] main from facebook:main

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

@@ -103,6 +103,7 @@ import {validateNoFreezingKnownMutableFunctions} from '../Validation/ValidateNoF
 import {inferMutationAliasingEffects} from '../Inference/InferMutationAliasingEffects';
 import {inferMutationAliasingRanges} from '../Inference/InferMutationAliasingRanges';
 import {validateNoDerivedComputationsInEffects} from '../Validation/ValidateNoDerivedComputationsInEffects';
+import {nameAnonymousFunctions} from '../Transform/NameAnonymousFunctions';
 
 export type CompilerPipelineValue =
   | {kind: 'ast'; name: string; value: CodegenFunction}
@@ -414,6 +415,15 @@ function runWithEnvironment(
     });
   }
 
+  if (env.config.enableNameAnonymousFunctions) {
+    nameAnonymousFunctions(hir);
+    log({
+      kind: 'hir',
+      name: 'NameAnonymougFunctions',
+      value: hir,
+    });
+  }
+
   const reactiveFunction = buildReactiveFunction(hir);
   log({
     kind: 'reactive',

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

@@ -3566,6 +3566,8 @@ function lowerFunctionToValue(
   let name: string | null = null;
   if (expr.isFunctionExpression()) {
     name = expr.get('id')?.node?.name ?? null;
+  } else if (expr.isFunctionDeclaration()) {
+    name = expr.get('id')?.node?.name ?? null;
   }
   const loweredFunc = lowerFunction(builder, expr);
   if (!loweredFunc) {

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

@@ -261,6 +261,8 @@ export const EnvironmentConfigSchema = z.object({
 
   enableFire: z.boolean().default(false),
 
+  enableNameAnonymousFunctions: z.boolean().default(false),
+
   /**
    * Enables inference and auto-insertion of effect dependencies. Takes in an array of
    * configurable module and import pairs to allow for user-land experimentation. For example,

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

@@ -15,6 +15,7 @@ import {Type, makeType} from './Types';
 import {z} from 'zod';
 import type {AliasingEffect} from '../Inference/AliasingEffects';
 import {isReservedWord} from '../Utils/Keyword';
+import {Err, Ok, Result} from '../Utils/Result';
 
 /*
  * *******************************************************************************************
@@ -1298,6 +1299,15 @@ export function forkTemporaryIdentifier(
   };
 }
 
+export function validateIdentifierName(
+  name: string,
+): Result<ValidIdentifierName, null> {
+  if (isReservedWord(name) || !t.isValidIdentifier(name)) {
+    return Err(null);
+  }
+  return Ok(makeIdentifierName(name).value);
+}
+
 /**
  * Creates a valid identifier name. This should *not* be used for synthesizing
  * identifier names: only call this method for identifier names that appear in the

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

@@ -43,6 +43,7 @@ import {
   ValidIdentifierName,
   getHookKind,
   makeIdentifierName,
+  validateIdentifierName,
 } from '../HIR/HIR';
 import {printIdentifier, printInstruction, printPlace} from '../HIR/PrintHIR';
 import {eachPatternOperand} from '../HIR/visitors';
@@ -2326,6 +2327,11 @@ function codegenInstructionValue(
         ),
         reactiveFunction,
       ).unwrap();
+
+      const validatedName =
+        instrValue.name != null
+          ? validateIdentifierName(instrValue.name)
+          : Err(null);
       if (instrValue.type === 'ArrowFunctionExpression') {
         let body: t.BlockStatement | t.Expression = fn.body;
         if (body.body.length === 1 && loweredFunc.directives.length == 0) {
@@ -2337,14 +2343,28 @@ function codegenInstructionValue(
         value = t.arrowFunctionExpression(fn.params, body, fn.async);
       } else {
         value = t.functionExpression(
-          fn.id ??
-            (instrValue.name != null ? t.identifier(instrValue.name) : null),
+          validatedName
+            .map<t.Identifier | null>(name => t.identifier(name))
+            .unwrapOr(null),
           fn.params,
           fn.body,
           fn.generator,
           fn.async,
         );
       }
+      if (
+        cx.env.config.enableNameAnonymousFunctions &&
+        validatedName.isErr() &&
+        instrValue.name != null
+      ) {
+        const name = instrValue.name;
+        value = t.memberExpression(
+          t.objectExpression([t.objectProperty(t.stringLiteral(name), value)]),
+          t.stringLiteral(name),
+          true,
+          false,
+        );
+      }
       break;
     }
     case 'TaggedTemplateExpression': {

compiler/packages/babel-plugin-react-compiler/src/Transform/NameAnonymousFunctions.ts

@@ -0,0 +1,173 @@
+/**
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+import {
+  FunctionExpression,
+  getHookKind,
+  HIRFunction,
+  IdentifierId,
+} from '../HIR';
+
+export function nameAnonymousFunctions(fn: HIRFunction): void {
+  if (fn.id == null) {
+    return;
+  }
+  const parentName = fn.id;
+  const functions = nameAnonymousFunctionsImpl(fn);
+  function visit(node: Node, prefix: string): void {
+    if (node.generatedName != null) {
+      /**
+       * Note that we don't generate a name for functions that already had one,
+       * so we'll only add the prefix to anonymous functions regardless of
+       * nesting depth.
+       */
+      const name = `${prefix}${node.generatedName}]`;
+      node.fn.name = name;
+    }
+    /**
+     * Whether or not we generated a name for the function at this node,
+     * traverse into its nested functions to assign them names
+     */
+    const nextPrefix = `${prefix}${node.generatedName ?? node.fn.name ?? '<anonymous>'} > `;
+    for (const inner of node.inner) {
+      visit(inner, nextPrefix);
+    }
+  }
+  for (const node of functions) {
+    visit(node, `${parentName}[`);
+  }
+}
+
+type Node = {
+  fn: FunctionExpression;
+  generatedName: string | null;
+  inner: Array<Node>;
+};
+
+function nameAnonymousFunctionsImpl(fn: HIRFunction): Array<Node> {
+  // Functions that we track to generate names for
+  const functions: Map<IdentifierId, Node> = new Map();
+  // Tracks temporaries that read from variables/globals/properties
+  const names: Map<IdentifierId, string> = new Map();
+  // Tracks all function nodes to bubble up for later renaming
+  const nodes: Array<Node> = [];
+  for (const block of fn.body.blocks.values()) {
+    for (const instr of block.instructions) {
+      const {lvalue, value} = instr;
+      switch (value.kind) {
+        case 'LoadGlobal': {
+          names.set(lvalue.identifier.id, value.binding.name);
+          break;
+        }
+        case 'LoadContext':
+        case 'LoadLocal': {
+          const name = value.place.identifier.name;
+          if (name != null && name.kind === 'named') {
+            names.set(lvalue.identifier.id, name.value);
+          }
+          break;
+        }
+        case 'PropertyLoad': {
+          const objectName = names.get(value.object.identifier.id);
+          if (objectName != null) {
+            names.set(
+              lvalue.identifier.id,
+              `${objectName}.${String(value.property)}`,
+            );
+          }
+          break;
+        }
+        case 'FunctionExpression': {
+          const inner = nameAnonymousFunctionsImpl(value.loweredFunc.func);
+          const node: Node = {
+            fn: value,
+            generatedName: null,
+            inner,
+          };
+          /**
+           * Bubble-up all functions, even if they're named, so that we can
+           * later generate names for any inner anonymous functions
+           */
+          nodes.push(node);
+          if (value.name == null) {
+            // but only generate names for anonymous functions
+            functions.set(lvalue.identifier.id, node);
+          }
+          break;
+        }
+        case 'StoreContext':
+        case 'StoreLocal': {
+          const node = functions.get(value.value.identifier.id);
+          const variableName = value.lvalue.place.identifier.name;
+          if (
+            node != null &&
+            variableName != null &&
+            variableName.kind === 'named'
+          ) {
+            node.generatedName = variableName.value;
+            functions.delete(value.value.identifier.id);
+          }
+          break;
+        }
+        case 'CallExpression':
+        case 'MethodCall': {
+          const callee =
+            value.kind === 'MethodCall' ? value.property : value.callee;
+          const hookKind = getHookKind(fn.env, callee.identifier);
+          let calleeName: string | null = null;
+          if (hookKind != null && hookKind !== 'Custom') {
+            calleeName = hookKind;
+          } else {
+            calleeName = names.get(callee.identifier.id) ?? '(anonymous)';
+          }
+          let fnArgCount = 0;
+          for (const arg of value.args) {
+            if (arg.kind === 'Identifier' && functions.has(arg.identifier.id)) {
+              fnArgCount++;
+            }
+          }
+          for (let i = 0; i < value.args.length; i++) {
+            const arg = value.args[i]!;
+            if (arg.kind === 'Spread') {
+              continue;
+            }
+            const node = functions.get(arg.identifier.id);
+            if (node != null) {
+              const generatedName =
+                fnArgCount > 1 ? `${calleeName}(arg${i})` : `${calleeName}()`;
+              node.generatedName = generatedName;
+              functions.delete(arg.identifier.id);
+            }
+          }
+          break;
+        }
+        case 'JsxExpression': {
+          for (const attr of value.props) {
+            if (attr.kind === 'JsxSpreadAttribute') {
+              continue;
+            }
+            const node = functions.get(attr.place.identifier.id);
+            if (node != null) {
+              const elementName =
+                value.tag.kind === 'BuiltinTag'
+                  ? value.tag.name
+                  : (names.get(value.tag.identifier.id) ?? null);
+              const propName =
+                elementName == null
+                  ? attr.name
+                  : `<${elementName}>.${attr.name}`;
+              node.generatedName = `${propName}`;
+              functions.delete(attr.place.identifier.id);
+            }
+          }
+          break;
+        }
+      }
+    }
+  }
+  return nodes;
+}