[compiler] Improve merging of scopes that invalidate together (facebook#34049)

We try to merge consecutive reactive scopes that will always invalidate
together, but there's one common case that isn't handled.

```js
const y = [[x]];
```

Here we'll create two consecutive scopes for the inner and outer array
expressions. Because the input to the second scope is a temporary,
they'll merge into one scope.

But if we name the inner array, the merging stops:

```js
const array = [x];
const y = [array];
```

This is because the merging logic checks if all the dependencies of the
second scope are outputs of the first scope, but doesn't account for
renaming due to LoadLocal/StoreLocal. The fix is to track these
temporaries.

---
[//]: # (BEGIN SAPLING FOOTER)
Stack created with [Sapling](https://sapling-scm.com). Best reviewed
with [ReviewStack](https://reviewstack.dev/facebook/react/pull/34049).
* __->__ facebook#34049
* facebook#34047
* facebook#34044

DiffTrain build for [ddf8bc3](facebook@ddf8bc3)

Author: pull[bot]

compiled/eslint-plugin-react-hooks/index.js

@@ -18099,6 +18099,61 @@ function phiTypeEquals(tA, tB) {
     return false;
 }
 
+const RESERVED_WORDS = new Set([
+    'break',
+    'case',
+    'catch',
+    'class',
+    'const',
+    'continue',
+    'debugger',
+    'default',
+    'delete',
+    'do',
+    'else',
+    'enum',
+    'export',
+    'extends',
+    'false',
+    'finally',
+    'for',
+    'function',
+    'if',
+    'import',
+    'in',
+    'instanceof',
+    'new',
+    'null',
+    'return',
+    'super',
+    'switch',
+    'this',
+    'throw',
+    'true',
+    'try',
+    'typeof',
+    'var',
+    'void',
+    'while',
+    'with',
+]);
+const STRICT_MODE_RESERVED_WORDS = new Set([
+    'let',
+    'static',
+    'implements',
+    'interface',
+    'package',
+    'private',
+    'protected',
+    'public',
+]);
+const STRICT_MODE_RESTRICTED_WORDS = new Set(['eval', 'arguments']);
+function isReservedWord(identifierName) {
+    return (RESERVED_WORDS.has(identifierName) ||
+        STRICT_MODE_RESERVED_WORDS.has(identifierName) ||
+        STRICT_MODE_RESTRICTED_WORDS.has(identifierName));
+}
+
 const GeneratedSource = Symbol();
 function isStatementBlockKind(kind) {
     return kind === 'block' || kind === 'catch';
@@ -18156,12 +18211,22 @@ function forkTemporaryIdentifier(id, source) {
     return Object.assign(Object.assign({}, source), { mutableRange: { start: makeInstructionId(0), end: makeInstructionId(0) }, id });
 }
 function makeIdentifierName(name) {
-    CompilerError.invariant(libExports$1.isValidIdentifier(name), {
-        reason: `Expected a valid identifier name`,
-        loc: GeneratedSource,
-        description: `\`${name}\` is not a valid JavaScript identifier`,
-        suggestions: null,
-    });
+    if (isReservedWord(name)) {
+        CompilerError.throwInvalidJS({
+            reason: 'Expected a non-reserved identifier name',
+            loc: GeneratedSource,
+            description: `\`${name}\` is a reserved word in JavaScript and cannot be used as an identifier name`,
+            suggestions: null,
+        });
+    }
+    else {
+        CompilerError.invariant(libExports$1.isValidIdentifier(name), {
+            reason: `Expected a valid identifier name`,
+            loc: GeneratedSource,
+            description: `\`${name}\` is not a valid JavaScript identifier`,
+            suggestions: null,
+        });
+    }
     return {
         kind: 'named',
         value: name,
@@ -21297,6 +21362,7 @@ function parseAliasingSignatureConfig(typeConfig, moduleName, loc) {
     const temporaries = typeConfig.temporaries.map(define);
     const effects = typeConfig.effects.map((effect) => {
         switch (effect.kind) {
+            case 'ImmutableCapture':
             case 'CreateFrom':
             case 'Capture':
             case 'Alias':
@@ -29739,6 +29805,96 @@ const TYPED_GLOBALS = [
                     returnValueKind: ValueKind.Mutable,
                 }),
             ],
+            [
+                'entries',
+                addFunction(DEFAULT_SHAPES, [], {
+                    positionalParams: [Effect.Capture],
+                    restParam: null,
+                    returnType: { kind: 'Object', shapeId: BuiltInArrayId },
+                    calleeEffect: Effect.Read,
+                    returnValueKind: ValueKind.Mutable,
+                    aliasing: {
+                        receiver: '@receiver',
+                        params: ['@object'],
+                        rest: null,
+                        returns: '@returns',
+                        temporaries: [],
+                        effects: [
+                            {
+                                kind: 'Create',
+                                into: '@returns',
+                                reason: ValueReason.KnownReturnSignature,
+                                value: ValueKind.Mutable,
+                            },
+                            {
+                                kind: 'Capture',
+                                from: '@object',
+                                into: '@returns',
+                            },
+                        ],
+                    },
+                }),
+            ],
+            [
+                'keys',
+                addFunction(DEFAULT_SHAPES, [], {
+                    positionalParams: [Effect.Read],
+                    restParam: null,
+                    returnType: { kind: 'Object', shapeId: BuiltInArrayId },
+                    calleeEffect: Effect.Read,
+                    returnValueKind: ValueKind.Mutable,
+                    aliasing: {
+                        receiver: '@receiver',
+                        params: ['@object'],
+                        rest: null,
+                        returns: '@returns',
+                        temporaries: [],
+                        effects: [
+                            {
+                                kind: 'Create',
+                                into: '@returns',
+                                reason: ValueReason.KnownReturnSignature,
+                                value: ValueKind.Mutable,
+                            },
+                            {
+                                kind: 'ImmutableCapture',
+                                from: '@object',
+                                into: '@returns',
+                            },
+                        ],
+                    },
+                }),
+            ],
+            [
+                'values',
+                addFunction(DEFAULT_SHAPES, [], {
+                    positionalParams: [Effect.Capture],
+                    restParam: null,
+                    returnType: { kind: 'Object', shapeId: BuiltInArrayId },
+                    calleeEffect: Effect.Read,
+                    returnValueKind: ValueKind.Mutable,
+                    aliasing: {
+                        receiver: '@receiver',
+                        params: ['@object'],
+                        rest: null,
+                        returns: '@returns',
+                        temporaries: [],
+                        effects: [
+                            {
+                                kind: 'Create',
+                                into: '@returns',
+                                reason: ValueReason.KnownReturnSignature,
+                                value: ValueKind.Mutable,
+                            },
+                            {
+                                kind: 'Capture',
+                                from: '@object',
+                                into: '@returns',
+                            },
+                        ],
+                    },
+                }),
+            ],
         ]),
     ],
     [
@@ -30558,6 +30714,11 @@ const AliasEffectSchema = zod.z.object({
     from: LifetimeIdSchema,
     into: LifetimeIdSchema,
 });
+const ImmutableCaptureEffectSchema = zod.z.object({
+    kind: zod.z.literal('ImmutableCapture'),
+    from: LifetimeIdSchema,
+    into: LifetimeIdSchema,
+});
 const CaptureEffectSchema = zod.z.object({
     kind: zod.z.literal('Capture'),
     from: LifetimeIdSchema,
@@ -30597,6 +30758,7 @@ const AliasingEffectSchema = zod.z.union([
     AssignEffectSchema,
     AliasEffectSchema,
     CaptureEffectSchema,
+    ImmutableCaptureEffectSchema,
     ImpureEffectSchema,
     MutateEffectSchema,
     MutateTransitiveConditionallySchema,
@@ -37325,6 +37487,7 @@ class FindLastUsageVisitor extends ReactiveFunctionVisitor {
 let Transform$4 = class Transform extends ReactiveFunctionTransform {
     constructor(lastUsage) {
         super();
+        this.temporaries = new Map();
         this.lastUsage = lastUsage;
     }
     transformScope(scopeBlock, state) {
@@ -37338,6 +37501,7 @@ let Transform$4 = class Transform extends ReactiveFunctionTransform {
         }
     }
     visitBlock(block, state) {
+        var _a;
         this.traverseBlock(block, state);
         let current = null;
         const merged = [];
@@ -37381,6 +37545,9 @@ let Transform$4 = class Transform extends ReactiveFunctionTransform {
                         case 'UnaryExpression': {
                             if (current !== null && instr.instruction.lvalue !== null) {
                                 current.lvalues.add(instr.instruction.lvalue.identifier.declarationId);
+                                if (instr.instruction.value.kind === 'LoadLocal') {
+                                    this.temporaries.set(instr.instruction.lvalue.identifier.declarationId, instr.instruction.value.place.identifier.declarationId);
+                                }
                             }
                             break;
                         }
@@ -37390,6 +37557,8 @@ let Transform$4 = class Transform extends ReactiveFunctionTransform {
                                     for (const lvalue of eachInstructionLValue(instr.instruction)) {
                                         current.lvalues.add(lvalue.identifier.declarationId);
                                     }
+                                    this.temporaries.set(instr.instruction.value.lvalue.place.identifier
+                                        .declarationId, (_a = this.temporaries.get(instr.instruction.value.value.identifier.declarationId)) !== null && _a !== void 0 ? _a : instr.instruction.value.value.identifier.declarationId);
                                 }
                                 else {
                                     reset();
@@ -37407,7 +37576,7 @@ let Transform$4 = class Transform extends ReactiveFunctionTransform {
                 }
                 case 'scope': {
                     if (current !== null &&
-                        canMergeScopes(current.block, instr) &&
+                        canMergeScopes(current.block, instr, this.temporaries) &&
                         areLValuesLastUsedByScope(instr.scope, current.lvalues, this.lastUsage)) {
                         current.block.scope.range.end = makeInstructionId(Math.max(current.block.scope.range.end, instr.scope.range.end));
                         for (const [key, value] of instr.scope.declarations) {
@@ -37503,7 +37672,7 @@ function areLValuesLastUsedByScope(scope, lvalues, lastUsage) {
     }
     return true;
 }
-function canMergeScopes(current, next) {
+function canMergeScopes(current, next, temporaries) {
     if (current.scope.reassignments.size !== 0 ||
         next.scope.reassignments.size !== 0) {
         return false;
@@ -37517,12 +37686,15 @@ function canMergeScopes(current, next) {
         path: [],
     }))), next.scope.dependencies) ||
         (next.scope.dependencies.size !== 0 &&
-            [...next.scope.dependencies].every(dep => isAlwaysInvalidatingType(dep.identifier.type) &&
-                Iterable_some(current.scope.declarations.values(), decl => decl.identifier.declarationId === dep.identifier.declarationId)))) {
+            [...next.scope.dependencies].every(dep => dep.path.length === 0 &&
+                isAlwaysInvalidatingType(dep.identifier.type) &&
+                Iterable_some(current.scope.declarations.values(), decl => decl.identifier.declarationId === dep.identifier.declarationId ||
+                    decl.identifier.declarationId ===
+                        temporaries.get(dep.identifier.declarationId))))) {
         return true;
     }
-    log(`  ${printReactiveScopeSummary(current.scope)}`);
-    log(`  ${printReactiveScopeSummary(next.scope)}`);
+    log(`  ${printReactiveScopeSummary(current.scope)} ${[...current.scope.declarations.values()].map(decl => decl.identifier.declarationId)}`);
+    log(`  ${printReactiveScopeSummary(next.scope)} ${[...next.scope.dependencies].map(dep => { var _a; return `${dep.identifier.declarationId} ${(_a = temporaries.get(dep.identifier.declarationId)) !== null && _a !== void 0 ? _a : dep.identifier.declarationId}`; })}`);
     return false;
 }
 function isAlwaysInvalidatingType(type) {

compiled/facebook-www/REVISION

@@ -1 +1 @@
-8de7aed8927d87a9e7e838f5d8ae28d5c30805d3
+ddf8bc3fbac7aefbf557e2e4a3e14d8de1b80872

compiled/facebook-www/REVISION_TRANSFORMS

@@ -1 +1 @@
-8de7aed8927d87a9e7e838f5d8ae28d5c30805d3
+ddf8bc3fbac7aefbf557e2e4a3e14d8de1b80872

compiled/facebook-www/React-dev.classic.js

@@ -1434,7 +1434,7 @@ __DEV__ &&
     exports.useTransition = function () {
       return resolveDispatcher().useTransition();
     };
-    exports.version = "19.2.0-www-classic-8de7aed8-20250730";
+    exports.version = "19.2.0-www-classic-ddf8bc3f-20250801";
     "undefined" !== typeof __REACT_DEVTOOLS_GLOBAL_HOOK__ &&
       "function" ===
         typeof __REACT_DEVTOOLS_GLOBAL_HOOK__.registerInternalModuleStop &&

compiled/facebook-www/React-dev.modern.js

@@ -1434,7 +1434,7 @@ __DEV__ &&
     exports.useTransition = function () {
       return resolveDispatcher().useTransition();
     };
-    exports.version = "19.2.0-www-modern-8de7aed8-20250730";
+    exports.version = "19.2.0-www-modern-ddf8bc3f-20250801";
     "undefined" !== typeof __REACT_DEVTOOLS_GLOBAL_HOOK__ &&
       "function" ===
         typeof __REACT_DEVTOOLS_GLOBAL_HOOK__.registerInternalModuleStop &&

compiled/facebook-www/React-prod.classic.js

@@ -610,4 +610,4 @@ exports.useSyncExternalStore = function (
 exports.useTransition = function () {
   return ReactSharedInternals.H.useTransition();
 };
-exports.version = "19.2.0-www-classic-8de7aed8-20250730";
+exports.version = "19.2.0-www-classic-ddf8bc3f-20250801";

compiled/facebook-www/React-prod.modern.js

@@ -610,4 +610,4 @@ exports.useSyncExternalStore = function (
 exports.useTransition = function () {
   return ReactSharedInternals.H.useTransition();
 };
-exports.version = "19.2.0-www-modern-8de7aed8-20250730";
+exports.version = "19.2.0-www-modern-ddf8bc3f-20250801";

compiled/facebook-www/React-profiling.classic.js

@@ -614,7 +614,7 @@ exports.useSyncExternalStore = function (
 exports.useTransition = function () {
   return ReactSharedInternals.H.useTransition();
 };
-exports.version = "19.2.0-www-classic-8de7aed8-20250730";
+exports.version = "19.2.0-www-classic-ddf8bc3f-20250801";
 "undefined" !== typeof __REACT_DEVTOOLS_GLOBAL_HOOK__ &&
   "function" ===
     typeof __REACT_DEVTOOLS_GLOBAL_HOOK__.registerInternalModuleStop &&

compiled/facebook-www/React-profiling.modern.js

@@ -614,7 +614,7 @@ exports.useSyncExternalStore = function (
 exports.useTransition = function () {
   return ReactSharedInternals.H.useTransition();
 };
-exports.version = "19.2.0-www-modern-8de7aed8-20250730";
+exports.version = "19.2.0-www-modern-ddf8bc3f-20250801";
 "undefined" !== typeof __REACT_DEVTOOLS_GLOBAL_HOOK__ &&
   "function" ===
     typeof __REACT_DEVTOOLS_GLOBAL_HOOK__.registerInternalModuleStop &&

compiled/facebook-www/ReactART-dev.classic.js

@@ -19318,10 +19318,10 @@ __DEV__ &&
     (function () {
       var internals = {
         bundleType: 1,
-        version: "19.2.0-www-classic-8de7aed8-20250730",
+        version: "19.2.0-www-classic-ddf8bc3f-20250801",
         rendererPackageName: "react-art",
         currentDispatcherRef: ReactSharedInternals,
-        reconcilerVersion: "19.2.0-www-classic-8de7aed8-20250730"
+        reconcilerVersion: "19.2.0-www-classic-ddf8bc3f-20250801"
       };
       internals.overrideHookState = overrideHookState;
       internals.overrideHookStateDeletePath = overrideHookStateDeletePath;
@@ -19355,7 +19355,7 @@ __DEV__ &&
     exports.Shape = Shape;
     exports.Surface = Surface;
     exports.Text = Text;
-    exports.version = "19.2.0-www-classic-8de7aed8-20250730";
+    exports.version = "19.2.0-www-classic-ddf8bc3f-20250801";
     "undefined" !== typeof __REACT_DEVTOOLS_GLOBAL_HOOK__ &&
       "function" ===
         typeof __REACT_DEVTOOLS_GLOBAL_HOOK__.registerInternalModuleStop &&