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Mirrored from https://github.com/247TaxiDriver/QOS-React.git
Synced Nov 7, 19:00 UTC
[compiler] Cleanup for @enablePreserveExistingMemoizationGuarantees (#34346)
I tried turning on `@enablePreserveExistingMemoizationGuarantees` by default and cleaned up a couple small things: * We emit freeze calls for StartMemoize deps but these had ValueReason.Other so the message wasn't great. We now treat these like other hook arguments. * PruneNonEscapingScopes was being too aggressive in this mode and memoizing even loads of globals. Switching to MemoizationLevel.Conditional ensures we build a graph that connects through to primitive-returning function calls, but doesn't unnecessarily force memoization otherwise. --- [//]: # (BEGIN SAPLING FOOTER) Stack created with [Sapling](https://sapling-scm.com). Best reviewed with [ReviewStack](https://reviewstack.dev/facebook/react/pull/34346). * #34347 * __->__ #34346
Joseph Savona committed
Sep 3, 2025 at 21:30 UTC
2710795a1ed339764d2fa76b6d7bc94dded6ee60
8 files changed
+138
-23
compiler/packages/babel-plugin-react-compiler/src/Inference/InferMutationAliasingEffects.ts
+1
-1
@@ -2089,7 +2089,7 @@ function computeSignatureForInstruction(
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effects.push({
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kind: 'Freeze',
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value: operand,
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- reason: ValueReason.Other,
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+ reason: ValueReason.HookCaptured,
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});
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}
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}
compiler/packages/babel-plugin-react-compiler/src/ReactiveScopes/PruneNonEscapingScopes.ts
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-4
@@ -546,7 +546,7 @@ class CollectDependenciesVisitor extends ReactiveFunctionVisitor<
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* memoization. Note: we may still prune primitive-producing scopes if
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* they don't ultimately escape at all.
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*/
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- const level = MemoizationLevel.Memoized;
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+ const level = MemoizationLevel.Conditional;
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return {
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lvalues: lvalue !== null ? [{place: lvalue, level}] : [],
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rvalues: [...eachReactiveValueOperand(value)],
@@ -701,9 +701,7 @@ class CollectDependenciesVisitor extends ReactiveFunctionVisitor<
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}
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case 'ComputedLoad':
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case 'PropertyLoad': {
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- const level = options.forceMemoizePrimitives
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- ? MemoizationLevel.Memoized
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- : MemoizationLevel.Conditional;
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+ const level = MemoizationLevel.Conditional;
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return {
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// Indirection for the inner value, memoized if the value is
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lvalues: lvalue !== null ? [{place: lvalue, level}] : [],
compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/meta-isms/repro-cx-namespace-nesting.expect.md
+2
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@@ -2,6 +2,7 @@
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## Input
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```javascript
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+// @compilationMode:"infer"
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import {makeArray} from 'shared-runtime';
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function Component() {
@@ -30,7 +31,7 @@ export const FIXTURE_ENTRYPOINT = {
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## Code
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```javascript
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-import { c as _c } from "react/compiler-runtime";
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+import { c as _c } from "react/compiler-runtime"; // @compilationMode:"infer"
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import { makeArray } from "shared-runtime";
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function Component() {
compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/meta-isms/repro-cx-namespace-nesting.js
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@@ -1,3 +1,4 @@
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+// @compilationMode:"infer"
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import {makeArray} from 'shared-runtime';
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function Component() {
compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/preserve-existing-memoization-guarantees/lambda-with-fbt-preserve-memoization.expect.md
new
+86
@@ -0,0 +1,86 @@
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+
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+## Input
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+
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+```javascript
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+// @enablePreserveExistingMemoizationGuarantees
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+import {fbt} from 'fbt';
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+
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+function Component() {
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+ const buttonLabel = () => {
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+ if (!someCondition) {
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+ return <fbt desc="My label">{'Purchase as a gift'}</fbt>;
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+ } else if (
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+ !iconOnly &&
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+ showPrice &&
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+ item?.current_gift_offer?.price?.formatted != null
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+ ) {
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+ return (
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+ <fbt desc="Gift button's label">
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+ {'Gift | '}
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+ <fbt:param name="price">
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+ {item?.current_gift_offer?.price?.formatted}
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+ </fbt:param>
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+ </fbt>
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+ );
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+ } else if (!iconOnly && !showPrice) {
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+ return <fbt desc="Gift button's label">{'Gift'}</fbt>;
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+ }
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+ };
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+
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+ return (
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+ <View>
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+ <Button text={buttonLabel()} />
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+ </View>
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+ );
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+}
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+
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+```
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+
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+## Code
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+
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+```javascript
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+import { c as _c } from "react/compiler-runtime"; // @enablePreserveExistingMemoizationGuarantees
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+import { fbt } from "fbt";
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+
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+function Component() {
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+ const $ = _c(1);
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+ const buttonLabel = _temp;
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+ let t0;
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+ if ($[0] === Symbol.for("react.memo_cache_sentinel")) {
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+ t0 = (
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+ <View>
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+ <Button text={buttonLabel()} />
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+ </View>
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+ );
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+ $[0] = t0;
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+ } else {
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+ t0 = $[0];
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+ }
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+ return t0;
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+}
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+function _temp() {
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+ if (!someCondition) {
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+ return fbt._("Purchase as a gift", null, { hk: "1gHj4g" });
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+ } else {
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+ if (
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+ !iconOnly &&
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+ showPrice &&
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+ item?.current_gift_offer?.price?.formatted != null
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+ ) {
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+ return fbt._(
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+ "Gift | {price}",
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+ [fbt._param("price", item?.current_gift_offer?.price?.formatted)],
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+ { hk: "3GTnGE" },
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+ );
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+ } else {
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+ if (!iconOnly && !showPrice) {
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+ return fbt._("Gift", null, { hk: "3fqfrk" });
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+ }
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+ }
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+ }
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+}
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+
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+```
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+
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+### Eval output
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+(kind: exception) Fixture not implemented
\ No newline at end of file
compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/preserve-existing-memoization-guarantees/lambda-with-fbt-preserve-memoization.js
new
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@@ -0,0 +1,31 @@
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+// @enablePreserveExistingMemoizationGuarantees
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+import {fbt} from 'fbt';
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+
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+function Component() {
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+ const buttonLabel = () => {
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+ if (!someCondition) {
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+ return <fbt desc="My label">{'Purchase as a gift'}</fbt>;
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+ } else if (
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+ !iconOnly &&
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+ showPrice &&
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+ item?.current_gift_offer?.price?.formatted != null
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+ ) {
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+ return (
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+ <fbt desc="Gift button's label">
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+ {'Gift | '}
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+ <fbt:param name="price">
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+ {item?.current_gift_offer?.price?.formatted}
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+ </fbt:param>
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+ </fbt>
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+ );
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+ } else if (!iconOnly && !showPrice) {
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+ return <fbt desc="Gift button's label">{'Gift'}</fbt>;
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+ }
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+ };
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+
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+ return (
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+ <View>
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+ <Button text={buttonLabel()} />
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+ </View>
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+ );
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+}
compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/primitive-reassigned-loop-force-scopes-enabled.expect.md
+14
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@@ -2,7 +2,7 @@
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## Input
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```javascript
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-// @enableForest
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+// @enablePreserveExistingMemoizationGuarantees
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function Component({base, start, increment, test}) {
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let value = base;
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for (let i = start; i < test; i += increment) {
@@ -27,25 +27,23 @@ export const FIXTURE_ENTRYPOINT = {
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## Code
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```javascript
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-import { c as _c } from "react/compiler-runtime"; // @enableForest
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+import { c as _c } from "react/compiler-runtime"; // @enablePreserveExistingMemoizationGuarantees
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function Component(t0) {
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- const $ = _c(5);
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+ const $ = _c(2);
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const { base, start, increment, test } = t0;
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- let value;
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- if ($[0] !== base || $[1] !== increment || $[2] !== start || $[3] !== test) {
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- value = base;
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- for (let i = start; i < test; i = i + increment, i) {
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- value = value + i;
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- }
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- $[0] = base;
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- $[1] = increment;
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- $[2] = start;
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- $[3] = test;
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- $[4] = value;
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+ let value = base;
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+ for (let i = start; i < test; i = i + increment, i) {
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+ value = value + i;
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+ }
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+ let t1;
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+ if ($[0] !== value) {
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+ t1 = <div>{value}</div>;
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+ $[0] = value;
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+ $[1] = t1;
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} else {
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- value = $[4];
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+ t1 = $[1];
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}
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- return <div>{value}</div>;
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+ return t1;
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}
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export const FIXTURE_ENTRYPOINT = {
compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/primitive-reassigned-loop-force-scopes-enabled.js
+1
-1
@@ -1,4 +1,4 @@
1
-// @enableForest
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+// @enablePreserveExistingMemoizationGuarantees
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function Component({base, start, increment, test}) {
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let value = base;
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for (let i = start; i < test; i += increment) {