[compiler] Add missing source locations to statements, expressions

Adds missing locations to all the statement kinds that we produce in codegenInstruction(), and adds generic handling of source locations for the nodes produced by codegenInstructionValue(). There are definitely some places where we are still missing a location, but this should address some of the known issues we've seen such as missing location on `throw`.

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

@@ -2089,7 +2089,7 @@ function computeSignatureForInstruction(
           effects.push({
             kind: 'Freeze',
             value: operand,
-            reason: ValueReason.Other,
+            reason: ValueReason.HookCaptured,
           });
         }
       }

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

@@ -945,7 +945,8 @@ function codegenTerminal(
       if (terminal.targetKind === 'implicit') {
         return null;
       }
-      return t.breakStatement(
+      return createBreakStatement(
+        terminal.loc,
         terminal.targetKind === 'labeled'
           ? t.identifier(codegenLabel(terminal.target))
           : null,
@@ -955,14 +956,16 @@ function codegenTerminal(
       if (terminal.targetKind === 'implicit') {
         return null;
       }
-      return t.continueStatement(
+      return createContinueStatement(
+        terminal.loc,
         terminal.targetKind === 'labeled'
           ? t.identifier(codegenLabel(terminal.target))
           : null,
       );
     }
     case 'for': {
-      return t.forStatement(
+      return createForStatement(
+        terminal.loc,
         codegenForInit(cx, terminal.init),
         codegenInstructionValueToExpression(cx, terminal.test),
         terminal.update !== null
@@ -1047,7 +1050,8 @@ function codegenTerminal(
             `Unhandled lvalue kind: ${iterableItem.value.lvalue.kind}`,
           );
       }
-      return t.forInStatement(
+      return createForInStatement(
+        terminal.loc,
         /*
          * Special handling here since we only want the VariableDeclarators without any inits
          * This needs to be updated when we handle non-trivial ForOf inits
@@ -1140,7 +1144,8 @@ function codegenTerminal(
             `Unhandled lvalue kind: ${iterableItem.value.lvalue.kind}`,
           );
       }
-      return t.forOfStatement(
+      return createForOfStatement(
+        terminal.loc,
         /*
          * Special handling here since we only want the VariableDeclarators without any inits
          * This needs to be updated when we handle non-trivial ForOf inits
@@ -1162,7 +1167,7 @@ function codegenTerminal(
           alternate = block;
         }
       }
-      return t.ifStatement(test, consequent, alternate);
+      return createIfStatement(terminal.loc, test, consequent, alternate);
     }
     case 'return': {
       const value = codegenPlaceToExpression(cx, terminal.value);
@@ -1173,7 +1178,8 @@ function codegenTerminal(
       return t.returnStatement(value);
     }
     case 'switch': {
-      return t.switchStatement(
+      return createSwitchStatement(
+        terminal.loc,
         codegenPlaceToExpression(cx, terminal.test),
         terminal.cases.map(case_ => {
           const test =
@@ -1186,15 +1192,26 @@ function codegenTerminal(
       );
     }
     case 'throw': {
-      return t.throwStatement(codegenPlaceToExpression(cx, terminal.value));
+      return createThrowStatement(
+        terminal.loc,
+        codegenPlaceToExpression(cx, terminal.value),
+      );
     }
     case 'do-while': {
       const test = codegenInstructionValueToExpression(cx, terminal.test);
-      return t.doWhileStatement(test, codegenBlock(cx, terminal.loop));
+      return createDoWhileStatement(
+        terminal.loc,
+        test,
+        codegenBlock(cx, terminal.loop),
+      );
     }
     case 'while': {
       const test = codegenInstructionValueToExpression(cx, terminal.test);
-      return t.whileStatement(test, codegenBlock(cx, terminal.loop));
+      return createWhileStatement(
+        terminal.loc,
+        test,
+        codegenBlock(cx, terminal.loop),
+      );
     }
     case 'label': {
       return codegenBlock(cx, terminal.block);
@@ -1205,7 +1222,8 @@ function codegenTerminal(
         catchParam = convertIdentifier(terminal.handlerBinding.identifier);
         cx.temp.set(terminal.handlerBinding.identifier.declarationId, null);
       }
-      return t.tryStatement(
+      return createTryStatement(
+        terminal.loc,
         codegenBlock(cx, terminal.block),
         t.catchClause(catchParam, codegenBlock(cx, terminal.handler)),
       );
@@ -1543,7 +1561,13 @@ const createExpressionStatement = withLoc(t.expressionStatement);
 const _createLabelledStatement = withLoc(t.labeledStatement);
 const createVariableDeclaration = withLoc(t.variableDeclaration);
 const createFunctionDeclaration = withLoc(t.functionDeclaration);
-const _createWhileStatement = withLoc(t.whileStatement);
+const createWhileStatement = withLoc(t.whileStatement);
+const createDoWhileStatement = withLoc(t.doWhileStatement);
+const createSwitchStatement = withLoc(t.switchStatement);
+const createIfStatement = withLoc(t.ifStatement);
+const createForStatement = withLoc(t.forStatement);
+const createForOfStatement = withLoc(t.forOfStatement);
+const createForInStatement = withLoc(t.forInStatement);
 const createTaggedTemplateExpression = withLoc(t.taggedTemplateExpression);
 const createLogicalExpression = withLoc(t.logicalExpression);
 const createSequenceExpression = withLoc(t.sequenceExpression);
@@ -1558,6 +1582,10 @@ const createJsxText = withLoc(t.jsxText);
 const createJsxClosingElement = withLoc(t.jsxClosingElement);
 const createJsxOpeningElement = withLoc(t.jsxOpeningElement);
 const createStringLiteral = withLoc(t.stringLiteral);
+const createThrowStatement = withLoc(t.throwStatement);
+const createTryStatement = withLoc(t.tryStatement);
+const createBreakStatement = withLoc(t.breakStatement);
+const createContinueStatement = withLoc(t.continueStatement);
 
 function createHookGuard(
   guard: ExternalFunction,
@@ -2314,6 +2342,9 @@ function codegenInstructionValue(
       );
     }
   }
+  if (instrValue.loc != null && instrValue.loc != GeneratedSource) {
+    value.loc = instrValue.loc;
+  }
   return value;
 }
 

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

@@ -546,7 +546,7 @@ class CollectDependenciesVisitor extends ReactiveFunctionVisitor<
            * memoization. Note: we may still prune primitive-producing scopes if
            * they don't ultimately escape at all.
            */
-          const level = MemoizationLevel.Memoized;
+          const level = MemoizationLevel.Conditional;
           return {
             lvalues: lvalue !== null ? [{place: lvalue, level}] : [],
             rvalues: [...eachReactiveValueOperand(value)],
@@ -701,9 +701,7 @@ class CollectDependenciesVisitor extends ReactiveFunctionVisitor<
       }
       case 'ComputedLoad':
       case 'PropertyLoad': {
-        const level = options.forceMemoizePrimitives
-          ? MemoizationLevel.Memoized
-          : MemoizationLevel.Conditional;
+        const level = MemoizationLevel.Conditional;
         return {
           // Indirection for the inner value, memoized if the value is
           lvalues: lvalue !== null ? [{place: lvalue, level}] : [],

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/align-scopes-nested-block-structure.expect.md

@@ -129,6 +129,7 @@ function useFoo(t0) {
         t1 = null;
         break bb0;
       }
+
       if (cond2) {
         mutate(s);
       }

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/align-scopes-reactive-scope-overlaps-label.expect.md

@@ -43,6 +43,7 @@ function useFoo(t0) {
   if ($[0] !== cond || $[1] !== value) {
     bb0: {
       items = [];
+
       if (cond) {
         break bb0;
       }

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/align-scopes-trycatch-nested-overlapping-range.expect.md

@@ -39,6 +39,7 @@ function Foo() {
       if (cond) {
         thing = makeObject_Primitives();
       }
+
       if (CONST_TRUE) {
         mutate(thing);
       }

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/assignment-in-nested-if.expect.md

@@ -23,6 +23,7 @@ import { c as _c } from "react/compiler-runtime";
 function useBar(props) {
   const $ = _c(1);
   let z;
+
   if (props.a) {
     if (props.b) {
       let t0;

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/capture-param-mutate.expect.md

@@ -67,6 +67,7 @@ function getNativeLogFunction(level) {
       ) {
         logLevel = LOG_LEVELS.warn;
       }
+
       if (global.__inspectorLog) {
         global.__inspectorLog(
           INSPECTOR_LEVELS[logLevel],
@@ -75,6 +76,7 @@ function getNativeLogFunction(level) {
           INSPECTOR_FRAMES_TO_SKIP,
         );
       }
+
       if (groupStack.length) {
         str = groupFormat("", str);
       }

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

@@ -47,9 +47,7 @@ function useKeyCommand() {
     };
 
     const moveLeft = { handler: handleKey("left") };
-
     const moveRight = { handler: handleKey("right") };
-
     t0 = [moveLeft, moveRight];
     $[0] = t0;
   } else {

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

@@ -33,7 +33,6 @@ function Component() {
   let y;
   if ($[0] === Symbol.for("react.memo_cache_sentinel")) {
     y = x = {};
-
     const foo = () => {
       x = makeArray();
     };

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/conditional-on-mutable.expect.md

@@ -44,6 +44,7 @@ function ComponentA(props) {
     if (b) {
       a.push(props.p0);
     }
+
     if (props.p1) {
       b.push(props.p2);
     }
@@ -68,6 +69,7 @@ function ComponentB(props) {
     if (mayMutate(b)) {
       a.push(props.p0);
     }
+
     if (props.p1) {
       b.push(props.p2);
     }

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/conditional-set-state-in-render.expect.md

@@ -34,6 +34,7 @@ function Component(props) {
   const foo = () => {
     setX(1);
   };
+
   if (props.cond) {
     setX(2);
     foo();

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/constant-prop-to-object-method.expect.md

@@ -36,7 +36,6 @@ function Foo() {
         return identity(1);
       },
     };
-
     t0 = x.foo();
     $[0] = t0;
   } else {

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

@@ -79,7 +79,6 @@ function foo() {
         value={[
           true,
           true,
-
           "a\nb",
           "\n",
           "a1b",

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/constant-propagation-unary-number.expect.md

@@ -48,7 +48,6 @@ function foo() {
           true,
           -Infinity,
           -NaN,
-
           -1 * NaN,
           -1 * Infinity,
           -1 * -Infinity,

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

@@ -28,6 +28,7 @@ function Component(props) {
     const a = [];
     const b = {};
     new Foo(a, b);
+
     new Foo(b);
     t0 = <div a={a} b={b} />;
     $[0] = t0;

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/context-variable-reassigned-objectmethod.expect.md

@@ -43,7 +43,6 @@ function Component(t0) {
         }
       },
     };
-
     invoke(obj.method, cond);
     $[0] = cond;
     $[1] = x;

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

@@ -27,6 +27,7 @@ export const FIXTURE_ENTRYPOINT = {
 ```javascript
 function Component(props) {
   debugger;
+
   if (props.cond) {
     debugger;
   } else {

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

@@ -26,6 +26,7 @@ function Component(props) {
   let x;
   if ($[0] !== props.a || $[1] !== props.b) {
     x = { a: props.a, b: props.b };
+
     delete x["b"];
     $[0] = props.a;
     $[1] = props.b;

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/dependencies-outputs.expect.md

@@ -46,6 +46,7 @@ function foo(a, b) {
     if (x.length) {
       y.push(x);
     }
+
     if (b) {
       y.push(b);
     }

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

@@ -46,6 +46,7 @@ function foo(x, y, z) {
   } else {
     items2 = $[2];
   }
+
   if (y) {
     items.push(x);
   }

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/dont-merge-if-dep-is-inner-declaration-of-previous-scope.expect.md

@@ -57,6 +57,7 @@ function Component(t0) {
   let y;
   if ($[0] !== a || $[1] !== b || $[2] !== c) {
     x = [];
+
     if (a) {
       let t1;
       if ($[5] !== b) {

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/extend-scopes-if.expect.md

@@ -48,6 +48,7 @@ function foo(a, b, c) {
   } else {
     x = $[3];
   }
+
   if (x.length) {
     return x;
   }

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/for-multiple-variable-declarations-in-initializer.expect.md

@@ -28,6 +28,7 @@ function Component(props) {
   let items;
   if ($[0] !== props.items) {
     items = [];
+
     for (let i = 0, length = props.items.length; i < length; i++) {
       items.push(props.items[i]);
     }

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/for-of-capture-item-of-local-collection-mutate-later-value-initially-null.expect.md

@@ -39,6 +39,7 @@ function Component(props) {
     for (const x of items) {
       lastItem = x;
     }
+
     if (lastItem != null) {
       lastItem.a = lastItem.a + 1;
     }

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/for-of-capture-item-of-local-collection-mutate-later.expect.md

@@ -39,6 +39,7 @@ function Component(props) {
     for (const x of items) {
       lastItem = x;
     }
+
     if (lastItem != null) {
       lastItem.a = lastItem.a + 1;
     }

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/function-expression-captures-value-later-frozen-jsx.expect.md

@@ -41,6 +41,7 @@ function Component(props) {
     t1 = $[1];
   }
   const onChange = t1;
+
   if (props.cond) {
   }
   let t2;

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/gating/codegen-instrument-forget-gating-test.expect.md

@@ -69,6 +69,7 @@ const Foo = isForgetEnabled_Fixtures()
       if (DEV && shouldInstrument)
         useRenderCounter("Foo", "/codegen-instrument-forget-gating-test.ts");
       const $ = _c(3);
+
       if (props.bar < 0) {
         return props.children;
       }

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/gating/gating-test-export-function-and-default.expect.md

@@ -63,6 +63,7 @@ const Foo = isForgetEnabled_Fixtures()
   ? function Foo(props) {
       "use forget";
       const $ = _c(3);
+
       if (props.bar < 0) {
         return props.children;
       }

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/hoisting-object-method.expect.md

@@ -35,7 +35,6 @@ function hoisting() {
         return bar();
       },
     };
-
     const bar = _temp;
 
     t0 = x.foo();

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/iife-return-modified-later-phi.expect.md

@@ -30,6 +30,7 @@ function Component(props) {
   let items;
   if ($[0] !== props.a || $[1] !== props.cond) {
     let t0;
+
     if (props.cond) {
       t0 = [];
     } else {

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/inline-jsx-transform.expect.md

@@ -390,6 +390,7 @@ function ConditionalJsx(t0) {
     t1 = $[0];
   }
   let content = t1;
+
   if (shouldWrap) {
     const t2 = content;
     let t3;

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/jsx-local-memberexpr-tag-conditional.expect.md

@@ -27,6 +27,7 @@ import * as SharedRuntime from "shared-runtime";
 function useFoo(t0) {
   const $ = _c(1);
   const { cond } = t0;
+
   if (cond) {
     let t1;
     if ($[0] === Symbol.for("react.memo_cache_sentinel")) {

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/merge-consecutive-nested-scopes.expect.md

@@ -30,6 +30,7 @@ const { getNumber } = require("shared-runtime");
 function Component(props) {
   const $ = _c(1);
   let x;
+
   if (props.cond) {
     let t0;
     if ($[0] === Symbol.for("react.memo_cache_sentinel")) {

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/meta-isms/repro-cx-namespace-nesting.expect.md

@@ -2,6 +2,7 @@
 ## Input
 
 ```javascript
+// @compilationMode:"infer"
 import {makeArray} from 'shared-runtime';
 
 function Component() {
@@ -30,7 +31,7 @@ export const FIXTURE_ENTRYPOINT = {
 ## Code
 
 ```javascript
-import { c as _c } from "react/compiler-runtime";
+import { c as _c } from "react/compiler-runtime"; // @compilationMode:"infer"
 import { makeArray } from "shared-runtime";
 
 function Component() {

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/meta-isms/repro-cx-namespace-nesting.js

@@ -1,3 +1,4 @@
+// @compilationMode:"infer"
 import {makeArray} from 'shared-runtime';
 
 function Component() {

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/module-scoped-bindings.expect.md

@@ -75,7 +75,6 @@ function Component() {
   if ($[0] !== state) {
     t0 = [
       React,
-
       state,
       CONST,
       NON_REASSIGNED_LET,

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/mutable-lifetime-loops.expect.md

@@ -94,12 +94,16 @@ function testFunction(props) {
         break;
       }
     }
+
     if (a) {
     }
+
     if (b) {
     }
+
     if (c) {
     }
+
     if (d) {
     }
 

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/mutable-lifetime-with-aliasing.expect.md

@@ -78,14 +78,19 @@ function Component(props) {
     x = {};
     x.b = b;
     const y = mutate(x, d);
+
     if (a) {
     }
+
     if (b) {
     }
+
     if (c) {
     }
+
     if (d) {
     }
+
     if (y) {
     }
 

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/mutable-liverange-loop.expect.md

@@ -51,12 +51,16 @@ function Component(props) {
       break;
     }
   }
+
   if (a) {
   }
+
   if (b) {
   }
+
   if (c) {
   }
+
   if (d) {
   }
 

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/new-mutability/capture-backedge-phi-with-later-mutation.expect.md

@@ -53,8 +53,10 @@ function Component(t0) {
   let z;
   if ($[0] !== prop1 || $[1] !== prop2) {
     let x = [{ value: prop1 }];
+
     while (x.length < 2) {
       arrayPush(x, { value: prop2 });
+
       if (x[0].value === prop1) {
         x = [{ value: prop2 }];
         const y = x;

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/new-mutability/iife-return-modified-later-phi.expect.md

@@ -30,6 +30,7 @@ function Component(props) {
   let items;
   if ($[0] !== props.a || $[1] !== props.cond) {
     let t0;
+
     if (props.cond) {
       t0 = [];
     } else {

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/new-mutability/object-expression-computed-key-object-mutated-later.expect.md

@@ -33,7 +33,6 @@ function Component(props) {
   if ($[0] !== props.value) {
     const key = {};
     context = { [key]: identity([props.value]) };
-
     mutate(key);
     $[0] = props.value;
     $[1] = context;

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/new-mutability/object-expression-computed-member.expect.md

@@ -44,7 +44,6 @@ function Component(props) {
       t2 = $[3];
     }
     context = t2;
-
     mutate(key);
     $[0] = props.value;
     $[1] = context;

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/new-mutability/repro-compiler-infinite-loop.expect.md

@@ -32,6 +32,7 @@ import fbt from "fbt";
 function Component() {
   const $ = _c(1);
   const sections = Object.keys(items);
+
   for (let i = 0; i < sections.length; i = i + 3, i) {
     chunks.push(sections.slice(i, i + 3).map(_temp));
   }

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/new-mutability/useCallback-reordering-depslist-assignment.expect.md

@@ -51,7 +51,6 @@ function useFoo(arr1, arr2) {
   if ($[2] !== arr2 || $[3] !== x) {
     let y;
     t1 = () => ({ y });
-
     (y = x.concat(arr2)), y;
     $[2] = arr2;
     $[3] = x;

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/nonmutating-capture-in-unsplittable-memo-block.expect.md

@@ -89,6 +89,7 @@ function useFoo(t0) {
     y = $[2];
     z = $[3];
   }
+
   if (z[0] !== y) {
     throw new Error("oh no!");
   }

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/object-expression-computed-key-object-mutated-later.expect.md

@@ -32,7 +32,6 @@ function Component(props) {
   if ($[0] !== props.value) {
     const key = {};
     context = { [key]: identity([props.value]) };
-
     mutate(key);
     $[0] = props.value;
     $[1] = context;

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/object-expression-computed-member.expect.md

@@ -43,7 +43,6 @@ function Component(props) {
       t2 = $[3];
     }
     context = t2;
-
     mutate(key);
     $[0] = props.value;
     $[1] = context;

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/object-method-maybe-alias.expect.md

@@ -38,13 +38,11 @@ function useHook(props) {
         return props;
       },
     };
-
     const y = {
       getY() {
         return "y";
       },
     };
-
     t0 = setProperty(x, y);
     $[0] = props;
     $[1] = t0;

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/object-method-shorthand-3.expect.md

@@ -39,7 +39,6 @@ function useHook(a) {
         return x;
       },
     };
-
     t0 = obj.method();
     $[0] = a;
     $[1] = t0;

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/object-method-shorthand-aliased-mutate-after.expect.md

@@ -37,7 +37,6 @@ function useHook(t0) {
         return value;
       },
     };
-
     mutate(x);
     $[0] = value;
     $[1] = obj;

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/object-method-shorthand-mutated-after.expect.md

@@ -37,7 +37,6 @@ function useHook(t0) {
         return x;
       },
     };
-
     mutate(obj);
     $[0] = value;
     $[1] = obj;

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/object-method-shorthand.expect.md

@@ -31,7 +31,6 @@ function Component() {
         return 1;
       },
     };
-
     t0 = obj.method();
     $[0] = t0;
   } else {

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/original-reactive-scopes-fork/capture-ref-for-later-mutation.expect.md

@@ -48,9 +48,7 @@ function useKeyCommand() {
     };
 
     const moveLeft = { handler: handleKey("left") };
-
     const moveRight = { handler: handleKey("right") };
-
     t0 = [moveLeft, moveRight];
     $[0] = t0;
   } else {

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/overlapping-scopes-interleaved-by-terminal.expect.md

@@ -27,6 +27,7 @@ export const FIXTURE_ENTRYPOINT = {
 function foo(a, b, c) {
   const x = [];
   const y = [];
+
   if (x) {
   }
 

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/preserve-existing-memoization-guarantees/lambda-with-fbt-preserve-memoization.expect.md

@@ -0,0 +1,86 @@
+
+## Input
+
+```javascript
+// @enablePreserveExistingMemoizationGuarantees
+import {fbt} from 'fbt';
+
+function Component() {
+  const buttonLabel = () => {
+    if (!someCondition) {
+      return <fbt desc="My label">{'Purchase as a gift'}</fbt>;
+    } else if (
+      !iconOnly &&
+      showPrice &&
+      item?.current_gift_offer?.price?.formatted != null
+    ) {
+      return (
+        <fbt desc="Gift button's label">
+          {'Gift | '}
+          <fbt:param name="price">
+            {item?.current_gift_offer?.price?.formatted}
+          </fbt:param>
+        </fbt>
+      );
+    } else if (!iconOnly && !showPrice) {
+      return <fbt desc="Gift button's label">{'Gift'}</fbt>;
+    }
+  };
+
+  return (
+    <View>
+      <Button text={buttonLabel()} />
+    </View>
+  );
+}
+
+```
+
+## Code
+
+```javascript
+import { c as _c } from "react/compiler-runtime"; // @enablePreserveExistingMemoizationGuarantees
+import { fbt } from "fbt";
+
+function Component() {
+  const $ = _c(1);
+  const buttonLabel = _temp;
+  let t0;
+  if ($[0] === Symbol.for("react.memo_cache_sentinel")) {
+    t0 = (
+      <View>
+        <Button text={buttonLabel()} />
+      </View>
+    );
+    $[0] = t0;
+  } else {
+    t0 = $[0];
+  }
+  return t0;
+}
+function _temp() {
+  if (!someCondition) {
+    return fbt._("Purchase as a gift", null, { hk: "1gHj4g" });
+  } else {
+    if (
+      !iconOnly &&
+      showPrice &&
+      item?.current_gift_offer?.price?.formatted != null
+    ) {
+      return fbt._(
+        "Gift | {price}",
+        [fbt._param("price", item?.current_gift_offer?.price?.formatted)],
+        { hk: "3GTnGE" },
+      );
+    } else {
+      if (!iconOnly && !showPrice) {
+        return fbt._("Gift", null, { hk: "3fqfrk" });
+      }
+    }
+  }
+}
+
+```
+      
+### Eval output
+(kind: exception) Fixture not implemented

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/preserve-existing-memoization-guarantees/lambda-with-fbt-preserve-memoization.js

@@ -0,0 +1,31 @@
+// @enablePreserveExistingMemoizationGuarantees
+import {fbt} from 'fbt';
+
+function Component() {
+  const buttonLabel = () => {
+    if (!someCondition) {
+      return <fbt desc="My label">{'Purchase as a gift'}</fbt>;
+    } else if (
+      !iconOnly &&
+      showPrice &&
+      item?.current_gift_offer?.price?.formatted != null
+    ) {
+      return (
+        <fbt desc="Gift button's label">
+          {'Gift | '}
+          <fbt:param name="price">
+            {item?.current_gift_offer?.price?.formatted}
+          </fbt:param>
+        </fbt>
+      );
+    } else if (!iconOnly && !showPrice) {
+      return <fbt desc="Gift button's label">{'Gift'}</fbt>;
+    }
+  };
+
+  return (
+    <View>
+      <Button text={buttonLabel()} />
+    </View>
+  );
+}

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/preserve-memo-validation/maybe-invalid-useMemo-no-memoblock-sideeffect.expect.md

@@ -36,6 +36,7 @@ import { useMemo } from "react";
 // (i.e. inferred non-mutable or non-escaping values don't get memoized)
 function useFoo(t0) {
   const { minWidth, styles, setStyles } = t0;
+
   if (styles.width > minWidth) {
     setStyles(styles);
   }

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/preserve-memo-validation/prune-nonescaping-useMemo-mult-returns-primitive.expect.md

@@ -34,6 +34,7 @@ import { identity } from "shared-runtime";
 
 function useFoo(cond) {
   let t0;
+
   if (cond) {
     t0 = 2;
   } else {

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/preserve-memo-validation/prune-nonescaping-useMemo-mult-returns.expect.md

@@ -34,6 +34,7 @@ import { identity } from "shared-runtime";
 
 function useFoo(cond) {
   let t0;
+
   if (cond) {
     t0 = identity(10);
   } else {

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/preserve-memo-validation/useCallback-nonescaping.expect.md

@@ -41,6 +41,7 @@ function Component(t0) {
   const { entity, children } = t0;
 
   const showMessage = () => entity != null;
+
   if (!showMessage()) {
     return children;
   }

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/preserve-memo-validation/useCallback-reordering-depslist-assignment.expect.md

@@ -50,7 +50,6 @@ function useFoo(arr1, arr2) {
   if ($[2] !== arr2 || $[3] !== x) {
     let y;
     t1 = () => ({ y });
-
     (y = x.concat(arr2)), y;
     $[2] = arr2;
     $[3] = x;

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/primitive-reassigned-loop-force-scopes-enabled.expect.md

@@ -2,7 +2,7 @@
 ## Input
 
 ```javascript
-// @enableForest
+// @enablePreserveExistingMemoizationGuarantees
 function Component({base, start, increment, test}) {
   let value = base;
   for (let i = start; i < test; i += increment) {
@@ -27,25 +27,23 @@ export const FIXTURE_ENTRYPOINT = {
 ## Code
 
 ```javascript
-import { c as _c } from "react/compiler-runtime"; // @enableForest
+import { c as _c } from "react/compiler-runtime"; // @enablePreserveExistingMemoizationGuarantees
 function Component(t0) {
-  const $ = _c(5);
+  const $ = _c(2);
   const { base, start, increment, test } = t0;
-  let value;
-  if ($[0] !== base || $[1] !== increment || $[2] !== start || $[3] !== test) {
-    value = base;
-    for (let i = start; i < test; i = i + increment, i) {
-      value = value + i;
-    }
-    $[0] = base;
-    $[1] = increment;
-    $[2] = start;
-    $[3] = test;
-    $[4] = value;
-  } else {
-    value = $[4];
+  let value = base;
+  for (let i = start; i < test; i = i + increment, i) {
+    value = value + i;
   }
-  return <div>{value}</div>;
+  let t1;
+  if ($[0] !== value) {
+    t1 = <div>{value}</div>;
+    $[0] = value;
+    $[1] = t1;
+  } else {
+    t1 = $[1];
+  }
+  return t1;
 }
 
 export const FIXTURE_ENTRYPOINT = {

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/primitive-reassigned-loop-force-scopes-enabled.js

@@ -1,4 +1,4 @@
-// @enableForest
+// @enablePreserveExistingMemoizationGuarantees
 function Component({base, start, increment, test}) {
   let value = base;
   for (let i = start; i < test; i += increment) {

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/propagate-scope-deps-hir-fork/conditional-on-mutable.expect.md

@@ -45,6 +45,7 @@ function ComponentA(props) {
     if (b) {
       a.push(props.p0);
     }
+
     if (props.p1) {
       b.push(props.p2);
     }
@@ -69,6 +70,7 @@ function ComponentB(props) {
     if (mayMutate(b)) {
       a.push(props.p0);
     }
+
     if (props.p1) {
       b.push(props.p2);
     }

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/propagate-scope-deps-hir-fork/iife-return-modified-later-phi.expect.md

@@ -31,6 +31,7 @@ function Component(props) {
   let items;
   if ($[0] !== props.a || $[1] !== props.cond) {
     let t0;
+
     if (props.cond) {
       t0 = [];
     } else {

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/propagate-scope-deps-hir-fork/reduce-reactive-deps/infer-object-method-uncond-access.expect.md

@@ -40,7 +40,6 @@ function useFoo(t0) {
         return identity(a.b.c);
       },
     };
-
     t1 = <Stringify x={x} shouldInvokeFns={true} />;
     $[0] = a;
     $[1] = t1;

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/propagate-scope-deps-hir-fork/switch-non-final-default.expect.md

@@ -61,7 +61,6 @@ function Component(props) {
         y = x;
       }
     }
-
     t0 = <Component data={x} />;
     $[0] = props.p0;
     $[1] = props.p2;

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/propagate-scope-deps-hir-fork/switch.expect.md

@@ -34,6 +34,7 @@ function Component(props) {
   let y;
   if ($[0] !== props.p0 || $[1] !== props.p2 || $[2] !== props.p3) {
     const x = [];
+
     switch (props.p0) {
       case true: {
         x.push(props.p2);
@@ -43,7 +44,6 @@ function Component(props) {
         y = x;
       }
     }
-
     t0 = <Component data={x} />;
     $[0] = props.p0;
     $[1] = props.p2;

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/propagate-scope-deps-hir-fork/useMemo-multiple-if-else.expect.md

@@ -47,6 +47,7 @@ function Component(props) {
       if (props.cond) {
         y.push(props.a);
       }
+
       if (props.cond2) {
         t0 = y;
         break bb0;

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/reactive-dependency-fixpoint.expect.md

@@ -33,6 +33,7 @@ function Component(props) {
   const $ = _c(2);
   let x = 0;
   let y = 0;
+
   while (x === 0) {
     x = y;
     y = props.value;

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

@@ -29,6 +29,7 @@ function Component(props) {
     let x = [];
     x.push(props.p0);
     const y = x;
+
     if (props.p1) {
       let t1;
       if ($[4] === Symbol.for("react.memo_cache_sentinel")) {

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/rename-source-variables-nested-object-method.expect.md

@@ -59,7 +59,6 @@ function useFoo(props) {
         return b;
       },
     };
-
     t1 = a.foo().bar();
     $0[0] = props;
     $0[1] = t1;

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/repro-backedge-reference-effect.expect.md

@@ -43,6 +43,7 @@ function Foo(t0) {
       <Stringify
         fn={() => {
           const arr = [];
+
           for (const selectedUser of userIds) {
             arr.push(selectedUser);
           }

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

@@ -49,7 +49,6 @@ function Component() {
   if ($[0] !== params) {
     t0 = (partialParams) => {
       const nextParams = { ...params, ...partialParams };
-
       nextParams.param = "value";
       console.log(nextParams);
     };

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/repro-invalid-reactivity-value-block.expect.md

@@ -82,6 +82,7 @@ function Foo() {
   const result = t1;
 
   useNoAlias(result, obj);
+
   if (shouldCaptureObj && result[0] !== obj) {
     throw new Error("Unexpected");
   }

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/repro-mutate-ref-in-function-passed-to-hook.expect.md

@@ -52,6 +52,7 @@ function Example() {
   if ($[0] === Symbol.for("react.memo_cache_sentinel")) {
     t0 = function updateStyles() {
       const foo = fooRef.current;
+
       if (barRef.current == null || foo == null) {
         return;
       }

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/repro-object-expression-computed-key-modified-during-after-construction-hoisted-sequence-expr.expect.md

@@ -67,7 +67,6 @@ function Component(props) {
     const key = {};
     const tmp = (mutate(key), key);
     const context = { [tmp]: identity([props.value]) };
-
     mutate(key);
     t0 = [context, key];
     $[0] = props.value;

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/repro-renaming-conflicting-decls.expect.md

@@ -72,7 +72,6 @@ function Component(props) {
   let t2;
   if ($[3] !== t0) {
     const linkProps = { url: t0 };
-
     const x = {};
     let t3;
     let t4;

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/repro-slow-validate-preserve-memo.expect.md

@@ -40,11 +40,7 @@ function useTest(t0) {
     t1 = Builder.makeBuilder(isNull, "hello world")
       ?.push("1", 2)
       ?.push(3, { a: 4, b: 5, c: data })
-      ?.push(
-        6,
-
-        data,
-      )
+      ?.push(6, data)
       ?.push(7, "8")
       ?.push("8", Builder.makeBuilder(!isNull)?.push(9).vals)?.vals;
     $[0] = data;

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/repro-unreachable-code-early-return-in-useMemo.expect.md

@@ -53,6 +53,7 @@ function Component(t0) {
       t1 = null;
       break bb0;
     }
+
     try {
       let t3;
       if ($[0] !== value) {

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/return-ref-callback-structure.expect.md

@@ -44,6 +44,7 @@ function Foo(t0) {
     t1 = $[0];
   }
   const s = t1;
+
   if (cond) {
     let t2;
     if ($[1] === Symbol.for("react.memo_cache_sentinel")) {

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/rules-of-hooks/rules-of-hooks-93dc5d5e538a.expect.md

@@ -20,6 +20,7 @@ function RegressionTest() {
 // Valid because the loop doesn't change the order of hooks calls.
 function RegressionTest() {
   const res = [];
+
   for (let i = 0; i !== 10 && true; ++i) {
     res.push(i);
   }

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/rules-of-hooks/rules-of-hooks-c1e8c7f4c191.expect.md

@@ -148,82 +148,121 @@ function MyComponent() {
 function MyComponent() {
   if (c) {
   }
+
   if (c) {
   }
+
   if (c) {
   }
+
   if (c) {
   }
+
   if (c) {
   }
+
   if (c) {
   }
+
   if (c) {
   }
+
   if (c) {
   }
+
   if (c) {
   }
+
   if (c) {
   }
+
   if (c) {
   }
+
   if (c) {
   }
+
   if (c) {
   }
+
   if (c) {
   }
+
   if (c) {
   }
+
   if (c) {
   }
+
   if (c) {
   }
+
   if (c) {
   }
+
   if (c) {
   }
+
   if (c) {
   }
+
   if (c) {
   }
+
   if (c) {
   }
+
   if (c) {
   }
+
   if (c) {
   }
+
   if (c) {
   }
+
   if (c) {
   }
+
   if (c) {
   }
+
   if (c) {
   }
+
   if (c) {
   }
+
   if (c) {
   }
+
   if (c) {
   }
+
   if (c) {
   }
+
   if (c) {
   }
+
   if (c) {
   }
+
   if (c) {
   }
+
   if (c) {
   }
+
   if (c) {
   }
+
   if (c) {
   }
+
   if (c) {
   }
+
   if (c) {
   }
 

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/rules-of-hooks/todo.bail.rules-of-hooks-6949b255e7eb.expect.md

@@ -97,6 +97,7 @@ const SomeName = () => {
   (FILLER ?? FILLER, FILLER) ?? FILLER;
 
   useSomeHook();
+
   if (anyConditionCanEvenBeFalse) {
     return null;
   }

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/switch-non-final-default.expect.md

@@ -60,7 +60,6 @@ function Component(props) {
         y = x;
       }
     }
-
     t0 = <Component data={x} />;
     $[0] = props.p0;
     $[1] = props.p2;

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

@@ -33,6 +33,7 @@ function Component(props) {
   let y;
   if ($[0] !== props.p0 || $[1] !== props.p2 || $[2] !== props.p3) {
     const x = [];
+
     switch (props.p0) {
       case true: {
         x.push(props.p2);
@@ -42,7 +43,6 @@ function Component(props) {
         y = x;
       }
     }
-
     t0 = <Component data={x} />;
     $[0] = props.p0;
     $[1] = props.p2;

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/todo-function-expression-captures-value-later-frozen.expect.md

@@ -32,6 +32,7 @@ function Component(props) {
     const onChange = (e) => {
       maybeMutate(x, e.target.value);
     };
+
     if (props.cond) {
     }
 

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/transform-fire/bailout-retry/infer-deps-on-retry.expect.md

@@ -46,6 +46,7 @@ function useFoo(t0) {
     () => {
       log(derived);
     },
+
     [derived],
     [derived],
   );

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/transform-fire/bailout-validate-conditional-hook.expect.md

@@ -39,6 +39,7 @@ import { Stringify } from "shared-runtime";
  */
 function Component(props) {
   const foo = _temp;
+
   if (props.cond) {
     const t0 = useFire(foo);
     useEffect(() => {

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/try-catch-within-object-method-returns-caught-value.expect.md

@@ -44,7 +44,6 @@ function Component(props) {
         }
       },
     };
-
     t0 = object.foo();
     $[0] = props;
     $[1] = t0;

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/try-catch-within-object-method.expect.md

@@ -39,7 +39,6 @@ function Component(props) {
         }
       },
     };
-
     t0 = object.foo();
     $[0] = t0;
   } else {

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/unlabeled-break-within-label-loop.expect.md

@@ -35,6 +35,7 @@ function useHook(end) {
     log = [];
     for (let i = 0; i < end + 1; i++) {
       log.push(`${i} @A`);
+
       if (i === end) {
         break;
       }

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/unlabeled-break-within-label-switch.expect.md

@@ -41,6 +41,7 @@ function useHook(cond) {
     bb0: switch (CONST_STRING0) {
       case CONST_STRING0: {
         log.push("@A");
+
         if (cond) {
           break bb0;
         }

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/use-effect-cleanup-reassigns.expect.md

@@ -65,12 +65,16 @@ function Component(t0) {
   if ($[0] === Symbol.for("react.memo_cache_sentinel")) {
     t1 = () => {
       let cleanedUp = false;
-      setTimeout(() => {
-        if (!cleanedUp) {
-          cleanedUp = true;
-          setCleanupCount(_temp);
-        }
-      }, 0);
+      setTimeout(
+        () => {
+          if (!cleanedUp) {
+            cleanedUp = true;
+            setCleanupCount(_temp);
+          }
+        },
+
+        0,
+      );
       return () => {
         if (!cleanedUp) {
           cleanedUp = true;

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/useImperativeHandle-ref-mutate.expect.md

@@ -43,7 +43,6 @@ function Component(t0) {
       const precomputed = prop + ref2.current;
       return { foo: () => prop + ref2.current + precomputed };
     };
-
     t2 = [prop];
     $[0] = prop;
     $[1] = t1;

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/useMemo-multiple-if-else.expect.md

@@ -46,6 +46,7 @@ function Component(props) {
       if (props.cond) {
         y.push(props.a);
       }
+
       if (props.cond2) {
         t0 = y;
         break bb0;

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/useMemo-switch-return.expect.md

@@ -50,7 +50,6 @@ function Component(props) {
         y = props.y;
       }
     }
-
     t0 = y;
   }
   const x = t0;

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/validate-no-set-state-in-render-uncalled-function-with-mutable-range-is-valid.expect.md

@@ -50,6 +50,7 @@ function Component(props) {
     t0 = $[1];
   }
   const onSubmit = t0;
+
   switch (currentStep) {
     case 0: {
       let t1;