{"parents":["a933d5e307d82635d2b171e23da9bcb926b909b0"],"files":[{"path":"compiler\/forget\/src\/CompilerPipeline.ts","status":"M"},{"path":"compiler\/forget\/src\/HIR\/HIR.ts","status":"M"},{"path":"compiler\/forget\/src\/ReactiveScopes\/ExtractScopeDeclarationsFromDestructuring.ts","status":"A"},{"path":"compiler\/forget\/src\/ReactiveScopes\/index.ts","status":"M"},{"path":"compiler\/forget\/src\/__tests__\/fixtures\/compiler\/destructuring-mixed-scope-and-local-variables-with-default.expect.md","status":"A"},{"previousPath":"compiler\/forget\/src\/__tests__\/fixtures\/compiler\/error.destructuring-mixed-scope-declarations-and-locals.expect.md","path":"compiler\/forget\/src\/__tests__\/fixtures\/compiler\/destructuring-mixed-scope-and-local-variables-with-default.js","status":"R073"},{"path":"compiler\/forget\/src\/__tests__\/fixtures\/compiler\/destructuring-mixed-scope-declarations-and-locals.expect.md","status":"A"},{"previousPath":"compiler\/forget\/src\/__tests__\/fixtures\/compiler\/error.destructuring-mixed-scope-declarations-and-locals.js","path":"compiler\/forget\/src\/__tests__\/fixtures\/compiler\/destructuring-mixed-scope-declarations-and-locals.js","status":"R100"},{"path":"compiler\/forget\/src\/__tests__\/fixtures\/compiler\/error.escape-analysis-destructured-rest-element.expect.md","status":"D"},{"path":"compiler\/forget\/src\/__tests__\/fixtures\/compiler\/error.unused-object-element-with-rest.expect.md","status":"D"},{"path":"compiler\/forget\/src\/__tests__\/fixtures\/compiler\/escape-analysis-destructured-rest-element.expect.md","status":"A"},{"previousPath":"compiler\/forget\/src\/__tests__\/fixtures\/compiler\/error.escape-analysis-destructured-rest-element.js","path":"compiler\/forget\/src\/__tests__\/fixtures\/compiler\/escape-analysis-destructured-rest-element.js","status":"R100"},{"path":"compiler\/forget\/src\/__tests__\/fixtures\/compiler\/unused-object-element-with-rest.expect.md","status":"A"},{"previousPath":"compiler\/forget\/src\/__tests__\/fixtures\/compiler\/error.unused-object-element-with-rest.js","path":"compiler\/forget\/src\/__tests__\/fixtures\/compiler\/unused-object-element-with-rest.js","status":"R100"}],"commit":{"revision":"46417a4ed77513d8e385ccd32e2103d5504bce4e","authorName":"Joe Savona","shortRevision":"46417a4ed7","authoredAt":"2023-05-18T09:25:28-07:00","authorEmail":"joesavona@fb.com","subject":"Fix bug with partially memoized destructuring"},"body":"","patch":"diff --git a\/compiler\/forget\/src\/CompilerPipeline.ts b\/compiler\/forget\/src\/CompilerPipeline.ts\nindex 983bc6bf19..96cc2b7f45 100644\n--- a\/compiler\/forget\/src\/CompilerPipeline.ts\n+++ b\/compiler\/forget\/src\/CompilerPipeline.ts\n@@ -32,6 +32,7 @@ import {\n buildReactiveBlocks,\n buildReactiveFunction,\n codegenReactiveFunction,\n+ extractScopeDeclarationsFromDestructuring,\n flattenReactiveLoops,\n flattenScopesWithHooks,\n inferReactiveScopeVariables,\n@@ -223,6 +224,13 @@ export function* run(\n value: reactiveFunction,\n });\n \n+ extractScopeDeclarationsFromDestructuring(reactiveFunction);\n+ yield log({\n+ kind: \"reactive\",\n+ name: \"ExtractScopeDeclarationsFromDestructuring\",\n+ value: reactiveFunction,\n+ });\n+\n renameVariables(reactiveFunction);\n yield log({\n kind: \"reactive\",\ndiff --git a\/compiler\/forget\/src\/HIR\/HIR.ts b\/compiler\/forget\/src\/HIR\/HIR.ts\nindex e181431211..89538ca2a3 100644\n--- a\/compiler\/forget\/src\/HIR\/HIR.ts\n+++ b\/compiler\/forget\/src\/HIR\/HIR.ts\n@@ -585,12 +585,7 @@ export type InstructionValue =\n value: Place;\n loc: SourceLocation;\n }\n- | {\n- kind: \"Destructure\";\n- lvalue: LValuePattern;\n- value: Place;\n- loc: SourceLocation;\n- }\n+ | Destructure\n | {\n kind: \"Primitive\";\n value: number | boolean | string | null | undefined;\n@@ -756,6 +751,14 @@ export type FunctionExpression = {\n expr: t.ArrowFunctionExpression | t.FunctionExpression;\n loc: SourceLocation;\n };\n+\n+export type Destructure = {\n+ kind: \"Destructure\";\n+ lvalue: LValuePattern;\n+ value: Place;\n+ loc: SourceLocation;\n+};\n+\n \/**\n * A place where data may be read from \/ written to:\n * - a variable (identifier)\ndiff --git a\/compiler\/forget\/src\/ReactiveScopes\/ExtractScopeDeclarationsFromDestructuring.ts b\/compiler\/forget\/src\/ReactiveScopes\/ExtractScopeDeclarationsFromDestructuring.ts\nnew file mode 100644\nindex 0000000000..22eae8e306\n--- \/dev\/null\n+++ b\/compiler\/forget\/src\/ReactiveScopes\/ExtractScopeDeclarationsFromDestructuring.ts\n@@ -0,0 +1,184 @@\n+\/**\n+ * Copyright (c) Meta Platforms, Inc. and affiliates.\n+ *\n+ * This source code is licensed under the MIT license found in the\n+ * LICENSE file in the root directory of this source tree.\n+ *\/\n+\n+import {\n+ Destructure,\n+ Environment,\n+ IdentifierId,\n+ InstructionKind,\n+ Place,\n+ ReactiveBlock,\n+ ReactiveFunction,\n+ ReactiveInstruction,\n+ ReactiveScopeBlock,\n+} from \"..\/HIR\";\n+import { eachPatternOperand, mapPatternOperands } from \"..\/HIR\/visitors\";\n+import { ReactiveFunctionTransform, visitReactiveFunction } from \".\/visitors\";\n+\n+\/**\n+ * Destructuring statements may sometimes define some variables which are declared by the scope,\n+ * and others that are only used locally within the scope, for example:\n+ *\n+ * ```\n+ * const {x, ...rest} = value;\n+ * return rest;\n+ * ```\n+ *\n+ * Here the scope structure turns into:\n+ *\n+ * ```\n+ * let c_0 = $[0] !== value;\n+ * let rest;\n+ * if (c_0) {\n+ * \/\/ OOPS! we want to reassign `rest` here, but\n+ * \/\/ `x` isn't declared anywhere!\n+ * {x, ...rest} = value;\n+ * $[0] = value;\n+ * $[1] = rest;\n+ * } else {\n+ * rest = $[1];\n+ * }\n+ * return rest;\n+ * ```\n+ *\n+ * Note that because `rest` is declared by the scope, we can't redeclare it in the\n+ * destructuring statement. But we have to declare `x`!\n+ *\n+ * This pass finds destructuring instructions that contain mixed values such as this,\n+ * and rewrites them to ensure that any scope variable assignments are extracted first\n+ * to a temporary and reassigned in a separate instruction. For example, the output\n+ * for the above would be along the lines of:\n+ *\n+ * ```\n+ * let c_0 = $[0] !== value;\n+ * let rest;\n+ * if (c_0) {\n+ * const {x, ...t0} = value; <-- replace `rest` with a temporary\n+ * rest = t0; \/\/ <-- and create a separate instruction to assign that to `rest`\n+ * $[0] = value;\n+ * $[1] = rest;\n+ * } else {\n+ * rest = $[1];\n+ * }\n+ * return rest;\n+ * ```\n+ *\n+ *\/\n+export function extractScopeDeclarationsFromDestructuring(\n+ fn: ReactiveFunction\n+): void {\n+ const state = new State(fn.env);\n+ visitReactiveFunction(fn, new Visitor(), state);\n+}\n+\n+class State {\n+ env: Environment;\n+ declared: Set = new Set();\n+\n+ constructor(env: Environment) {\n+ this.env = env;\n+ }\n+}\n+\n+class Visitor extends ReactiveFunctionTransform {\n+ override visitScope(scope: ReactiveScopeBlock, state: State): void {\n+ for (const [, declaration] of scope.scope.declarations) {\n+ state.declared.add(declaration.identifier.id);\n+ }\n+ this.traverseScope(scope, state);\n+ }\n+\n+ override visitBlock(block: ReactiveBlock, state: State): void {\n+ \/\/ Traverse first to transform inner items\n+ this.traverseBlock(block, state);\n+\n+ \/\/ Then transform any mixed destructuring instructions\n+ let nextBlock: ReactiveBlock | null = null;\n+ for (let i = 0; i < block.length; i++) {\n+ const instr = block[i];\n+ if (\n+ instr.kind === \"instruction\" &&\n+ instr.instruction.value.kind === \"Destructure\"\n+ ) {\n+ const transformed = transformDestructuring(\n+ state,\n+ instr.instruction,\n+ instr.instruction.value\n+ );\n+ if (transformed) {\n+ nextBlock ??= block.slice(0, i);\n+ transformed.forEach((instruction) => {\n+ nextBlock?.push({\n+ kind: \"instruction\",\n+ instruction,\n+ });\n+ });\n+ continue;\n+ }\n+ } else if (nextBlock !== null) {\n+ nextBlock.push(instr);\n+ }\n+ }\n+ if (nextBlock !== null) {\n+ block.length = 0;\n+ block.push(...nextBlock);\n+ }\n+ }\n+}\n+\n+function transformDestructuring(\n+ state: State,\n+ instr: ReactiveInstruction,\n+ destructure: Destructure\n+): null | Array {\n+ let reassigned: Set = new Set();\n+ let hasDeclaration = false;\n+ for (const place of eachPatternOperand(destructure.lvalue.pattern)) {\n+ const isDeclared = state.declared.has(place.identifier.id);\n+ if (isDeclared) {\n+ reassigned.add(place.identifier.id);\n+ }\n+ hasDeclaration ||= !isDeclared;\n+ }\n+ if (reassigned.size === 0 || !hasDeclaration) {\n+ return null;\n+ }\n+ \/\/ Else it's a mix, replace the reassigned items in the destructuring with temporary\n+ \/\/ variables and emit separate assignment statements for them\n+ const instructions: Array = [];\n+ const renamed: Map = new Map();\n+ mapPatternOperands(destructure.lvalue.pattern, (place) => {\n+ if (!reassigned.has(place.identifier.id)) {\n+ return place;\n+ }\n+ const tempId = state.env.nextIdentifierId;\n+ const temporary = {\n+ ...place,\n+ identifier: { ...place.identifier, id: tempId, name: `t${tempId}` },\n+ };\n+ renamed.set(place, temporary);\n+ return temporary;\n+ });\n+ instructions.push(instr);\n+ for (const [original, temporary] of renamed) {\n+ instructions.push({\n+ id: instr.id,\n+ lvalue: null,\n+ value: {\n+ kind: \"StoreLocal\",\n+ lvalue: {\n+ kind: InstructionKind.Reassign,\n+ place: original,\n+ },\n+ value: temporary,\n+ loc: destructure.loc,\n+ },\n+ loc: instr.loc,\n+ });\n+ }\n+ return instructions;\n+}\ndiff --git a\/compiler\/forget\/src\/ReactiveScopes\/index.ts b\/compiler\/forget\/src\/ReactiveScopes\/index.ts\nindex 8d042ee6e0..f3da369604 100644\n--- a\/compiler\/forget\/src\/ReactiveScopes\/index.ts\n+++ b\/compiler\/forget\/src\/ReactiveScopes\/index.ts\n@@ -9,6 +9,7 @@ export { alignReactiveScopesToBlockScopes } from \".\/AlignReactiveScopesToBlockSc\n export { buildReactiveBlocks } from \".\/BuildReactiveBlocks\";\n export { buildReactiveFunction } from \".\/BuildReactiveFunction\";\n export { codegenReactiveFunction } from \".\/CodegenReactiveFunction\";\n+export { extractScopeDeclarationsFromDestructuring } from \".\/ExtractScopeDeclarationsFromDestructuring\";\n export { flattenReactiveLoops } from \".\/FlattenReactiveLoops\";\n export { flattenScopesWithHooks } from \".\/FlattenScopesWithHooks\";\n export { inferReactiveScopeVariables } from \".\/InferReactiveScopeVariables\";\ndiff --git a\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/destructuring-mixed-scope-and-local-variables-with-default.expect.md b\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/destructuring-mixed-scope-and-local-variables-with-default.expect.md\nnew file mode 100644\nindex 0000000000..9cc3238b14\n--- \/dev\/null\n+++ b\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/destructuring-mixed-scope-and-local-variables-with-default.expect.md\n@@ -0,0 +1,101 @@\n+\n+## Input\n+\n+```javascript\n+function Component(props) {\n+ const post = useFragment(graphql`...`, props.post);\n+ const allUrls = [];\n+ \/\/ `media` and `urls` are exported from the scope that will wrap this code,\n+ \/\/ but `comments` is not (it doesn't need to be memoized, bc the callback\n+ \/\/ only checks `comments.length`)\n+ \/\/ because of the scope, the let declaration for media and urls are lifted\n+ \/\/ out of the scope, and the destructure statement ends up turning into\n+ \/\/ a reassignment, instead of a const declaration. this means we try to\n+ \/\/ reassign `comments` when there's no declaration for it.\n+ const { media = null, comments = [], urls = [] } = post;\n+ const onClick = (e) => {\n+ if (!comments.length) {\n+ return;\n+ }\n+ log(comments.length);\n+ };\n+ allUrls.push(...urls);\n+ return ;\n+}\n+\n+```\n+\n+## Code\n+\n+```javascript\n+import { unstable_useMemoCache as useMemoCache } from \"react\";\n+function Component(props) {\n+ const $ = useMemoCache(12);\n+ const post = useFragment(graphql`...`, props.post);\n+ const c_0 = $[0] !== post;\n+ let media;\n+ let onClick;\n+ if (c_0) {\n+ const allUrls = [];\n+\n+ const { media: t0, comments: t2, urls: t81 } = post;\n+ const c_3 = $[3] !== t0;\n+ let t1;\n+ if (c_3) {\n+ t1 = t0 === undefined ? null : t0;\n+ $[3] = t0;\n+ $[4] = t1;\n+ } else {\n+ t1 = $[4];\n+ }\n+ media = t1;\n+ const c_5 = $[5] !== t2;\n+ let t3;\n+ if (c_5) {\n+ t3 = t2 === undefined ? [] : t2;\n+ $[5] = t2;\n+ $[6] = t3;\n+ } else {\n+ t3 = $[6];\n+ }\n+ const comments = t3;\n+ const urls = t81 === undefined ? [] : t81;\n+ const c_7 = $[7] !== comments.length;\n+ let t4;\n+ if (c_7) {\n+ t4 = (e) => {\n+ if (!comments.length) {\n+ return;\n+ }\n+ log(comments.length);\n+ };\n+ $[7] = comments.length;\n+ $[8] = t4;\n+ } else {\n+ t4 = $[8];\n+ }\n+ onClick = t4;\n+ allUrls.push(...urls);\n+ $[0] = post;\n+ $[1] = media;\n+ $[2] = onClick;\n+ } else {\n+ media = $[1];\n+ onClick = $[2];\n+ }\n+ const c_9 = $[9] !== media;\n+ const c_10 = $[10] !== onClick;\n+ let t5;\n+ if (c_9 || c_10) {\n+ t5 = ;\n+ $[9] = media;\n+ $[10] = onClick;\n+ $[11] = t5;\n+ } else {\n+ t5 = $[11];\n+ }\n+ return t5;\n+}\n+\n+```\n+ \n\\ No newline at end of file\ndiff --git a\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/error.destructuring-mixed-scope-declarations-and-locals.expect.md b\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/destructuring-mixed-scope-and-local-variables-with-default.js\nsimilarity index 73%\nrename from compiler\/forget\/src\/__tests__\/fixtures\/compiler\/error.destructuring-mixed-scope-declarations-and-locals.expect.md\nrename to compiler\/forget\/src\/__tests__\/fixtures\/compiler\/destructuring-mixed-scope-and-local-variables-with-default.js\nindex f583d24bbd..6067b285f0 100644\n--- a\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/error.destructuring-mixed-scope-declarations-and-locals.expect.md\n+++ b\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/destructuring-mixed-scope-and-local-variables-with-default.js\n@@ -1,7 +1,3 @@\n-\n-## Input\n-\n-```javascript\n function Component(props) {\n const post = useFragment(graphql`...`, props.post);\n const allUrls = [];\n@@ -12,7 +8,7 @@ function Component(props) {\n \/\/ out of the scope, and the destructure statement ends up turning into\n \/\/ a reassignment, instead of a const declaration. this means we try to\n \/\/ reassign `comments` when there's no declaration for it.\n- const { media, comments, urls } = post;\n+ const { media = null, comments = [], urls = [] } = post;\n const onClick = (e) => {\n if (!comments.length) {\n return;\n@@ -22,14 +18,3 @@ function Component(props) {\n allUrls.push(...urls);\n return ;\n }\n-\n-```\n-\n-\n-## Error\n-\n-```\n-[ReactForget] Invariant: Encountered a destructuring operation where some identifiers are already declared (reassignments) but others are not (declarations) (11:11)\n-```\n- \n- \n\\ No newline at end of file\ndiff --git a\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/destructuring-mixed-scope-declarations-and-locals.expect.md b\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/destructuring-mixed-scope-declarations-and-locals.expect.md\nnew file mode 100644\nindex 0000000000..237f6c1024\n--- \/dev\/null\n+++ b\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/destructuring-mixed-scope-declarations-and-locals.expect.md\n@@ -0,0 +1,81 @@\n+\n+## Input\n+\n+```javascript\n+function Component(props) {\n+ const post = useFragment(graphql`...`, props.post);\n+ const allUrls = [];\n+ \/\/ `media` and `urls` are exported from the scope that will wrap this code,\n+ \/\/ but `comments` is not (it doesn't need to be memoized, bc the callback\n+ \/\/ only checks `comments.length`)\n+ \/\/ because of the scope, the let declaration for media and urls are lifted\n+ \/\/ out of the scope, and the destructure statement ends up turning into\n+ \/\/ a reassignment, instead of a const declaration. this means we try to\n+ \/\/ reassign `comments` when there's no declaration for it.\n+ const { media, comments, urls } = post;\n+ const onClick = (e) => {\n+ if (!comments.length) {\n+ return;\n+ }\n+ log(comments.length);\n+ };\n+ allUrls.push(...urls);\n+ return ;\n+}\n+\n+```\n+\n+## Code\n+\n+```javascript\n+import { unstable_useMemoCache as useMemoCache } from \"react\";\n+function Component(props) {\n+ const $ = useMemoCache(8);\n+ const post = useFragment(graphql`...`, props.post);\n+ const c_0 = $[0] !== post;\n+ let media;\n+ let onClick;\n+ if (c_0) {\n+ const allUrls = [];\n+\n+ const { media: t83, comments, urls } = post;\n+ media = t83;\n+ const c_3 = $[3] !== comments.length;\n+ let t0;\n+ if (c_3) {\n+ t0 = (e) => {\n+ if (!comments.length) {\n+ return;\n+ }\n+ log(comments.length);\n+ };\n+ $[3] = comments.length;\n+ $[4] = t0;\n+ } else {\n+ t0 = $[4];\n+ }\n+ onClick = t0;\n+ allUrls.push(...urls);\n+ $[0] = post;\n+ $[1] = media;\n+ $[2] = onClick;\n+ } else {\n+ media = $[1];\n+ onClick = $[2];\n+ }\n+ const c_5 = $[5] !== media;\n+ const c_6 = $[6] !== onClick;\n+ let t1;\n+ if (c_5 || c_6) {\n+ t1 = ;\n+ $[5] = media;\n+ $[6] = onClick;\n+ $[7] = t1;\n+ } else {\n+ t1 = $[7];\n+ }\n+ return t1;\n+}\n+\n+```\n+ \n\\ No newline at end of file\ndiff --git a\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/error.destructuring-mixed-scope-declarations-and-locals.js b\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/destructuring-mixed-scope-declarations-and-locals.js\nsimilarity index 100%\nrename from compiler\/forget\/src\/__tests__\/fixtures\/compiler\/error.destructuring-mixed-scope-declarations-and-locals.js\nrename to compiler\/forget\/src\/__tests__\/fixtures\/compiler\/destructuring-mixed-scope-declarations-and-locals.js\ndiff --git a\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/error.escape-analysis-destructured-rest-element.expect.md b\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/error.escape-analysis-destructured-rest-element.expect.md\ndeleted file mode 100644\nindex 6403b6bb22..0000000000\n--- a\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/error.escape-analysis-destructured-rest-element.expect.md\n+++ \/dev\/null\n@@ -1,22 +0,0 @@\n-\n-## Input\n-\n-```javascript\n-function Component(props) {\n- \/\/ b is an object, must be memoized even though the input is not memoized\n- const { a, ...b } = props.a;\n- \/\/ d is an array, mut be memoized even though the input is not memoized\n- const [c, ...d] = props.c;\n- return

<\/div>;\n-}\n-\n-```\n-\n-\n-## Error\n-\n-```\n-[ReactForget] Invariant: Encountered a destructuring operation where some identifiers are already declared (reassignments) but others are not (declarations) (3:3)\n-```\n- \n- \n\\ No newline at end of file\ndiff --git a\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/error.unused-object-element-with-rest.expect.md b\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/error.unused-object-element-with-rest.expect.md\ndeleted file mode 100644\nindex 3f7f2ee810..0000000000\n--- a\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/error.unused-object-element-with-rest.expect.md\n+++ \/dev\/null\n@@ -1,20 +0,0 @@\n-\n-## Input\n-\n-```javascript\n-function Foo(props) {\n- \/\/ can't remove `unused` since it affects which properties are copied into `rest`\n- const { unused, ...rest } = props.a;\n- return rest;\n-}\n-\n-```\n-\n-\n-## Error\n-\n-```\n-[ReactForget] Invariant: Encountered a destructuring operation where some identifiers are already declared (reassignments) but others are not (declarations) (3:3)\n-```\n- \n- \n\\ No newline at end of file\ndiff --git a\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/escape-analysis-destructured-rest-element.expect.md b\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/escape-analysis-destructured-rest-element.expect.md\nnew file mode 100644\nindex 0000000000..b80443d5f4\n--- \/dev\/null\n+++ b\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/escape-analysis-destructured-rest-element.expect.md\n@@ -0,0 +1,56 @@\n+\n+## Input\n+\n+```javascript\n+function Component(props) {\n+ \/\/ b is an object, must be memoized even though the input is not memoized\n+ const { a, ...b } = props.a;\n+ \/\/ d is an array, mut be memoized even though the input is not memoized\n+ const [c, ...d] = props.c;\n+ return

<\/div>;\n+}\n+\n+```\n+\n+## Code\n+\n+```javascript\n+import { unstable_useMemoCache as useMemoCache } from \"react\";\n+function Component(props) {\n+ const $ = useMemoCache(7);\n+ const c_0 = $[0] !== props.a;\n+ let b;\n+ if (c_0) {\n+ const { a, ...t30 } = props.a;\n+ b = t30;\n+ $[0] = props.a;\n+ $[1] = b;\n+ } else {\n+ b = $[1];\n+ }\n+ const c_2 = $[2] !== props.c;\n+ let d;\n+ if (c_2) {\n+ const [c, ...t31] = props.c;\n+ d = t31;\n+ $[2] = props.c;\n+ $[3] = d;\n+ } else {\n+ d = $[3];\n+ }\n+ const c_4 = $[4] !== b;\n+ const c_5 = $[5] !== d;\n+ let t0;\n+ if (c_4 || c_5) {\n+ t0 =

;\n+ $[4] = b;\n+ $[5] = d;\n+ $[6] = t0;\n+ } else {\n+ t0 = $[6];\n+ }\n+ return t0;\n+}\n+\n+```\n+ \n\\ No newline at end of file\ndiff --git a\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/error.escape-analysis-destructured-rest-element.js b\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/escape-analysis-destructured-rest-element.js\nsimilarity index 100%\nrename from compiler\/forget\/src\/__tests__\/fixtures\/compiler\/error.escape-analysis-destructured-rest-element.js\nrename to compiler\/forget\/src\/__tests__\/fixtures\/compiler\/escape-analysis-destructured-rest-element.js\ndiff --git a\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/unused-object-element-with-rest.expect.md b\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/unused-object-element-with-rest.expect.md\nnew file mode 100644\nindex 0000000000..9a3643b9d4\n--- \/dev\/null\n+++ b\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/unused-object-element-with-rest.expect.md\n@@ -0,0 +1,33 @@\n+\n+## Input\n+\n+```javascript\n+function Foo(props) {\n+ \/\/ can't remove `unused` since it affects which properties are copied into `rest`\n+ const { unused, ...rest } = props.a;\n+ return rest;\n+}\n+\n+```\n+\n+## Code\n+\n+```javascript\n+import { unstable_useMemoCache as useMemoCache } from \"react\";\n+function Foo(props) {\n+ const $ = useMemoCache(2);\n+ const c_0 = $[0] !== props.a;\n+ let rest;\n+ if (c_0) {\n+ const { unused, ...t16 } = props.a;\n+ rest = t16;\n+ $[0] = props.a;\n+ $[1] = rest;\n+ } else {\n+ rest = $[1];\n+ }\n+ return rest;\n+}\n+\n+```\n+ \n\\ No newline at end of file\ndiff --git a\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/error.unused-object-element-with-rest.js b\/compiler\/forget\/src\/__tests__\/fixtures\/compiler\/unused-object-element-with-rest.js\nsimilarity index 100%\nrename from compiler\/forget\/src\/__tests__\/fixtures\/compiler\/error.unused-object-element-with-rest.js\nrename to compiler\/forget\/src\/__tests__\/fixtures\/compiler\/unused-object-element-with-rest.js\n"}

dillon1000/react

Files changed