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fix(es/minifier): guard computed class keys in new functions Computed class element keys are evaluated while defining the class and can run in the surrounding constructor scope. The usage analyzer may not mark the outer constructor scope as using arguments for these keys, so the new-function argument cleanup must handle them explicitly. Bail out when the current constructor evaluation context may observe the constructor argument list through arguments, this, a referenced named function expression, new.target, or eval, including computed class keys and class heritage expressions. Add fixture and execution coverage for computed class key cases.

skku970412:fix-new-expr-useless-args-11684

6 hours ago

fix(es/minifier): guard new function param observability Default parameter initializers run before the constructor body and can observe the actual constructor argument list through new.target, this.constructor, or a referenced named function expression.\n\nInclude function parameters in the direct new-function constructor observability checks before dropping trailing pure extra arguments, and add fixture plus execution coverage for these parameter-default cases.

skku970412:fix-new-expr-useless-args-11684

7 hours ago

fix(es/minifier): guard new function arg observability Constructor calls can expose their actual argument list through the constructor function object in sloppy-mode code, for example through `this.constructor.arguments` or a referenced named function expression.\n\nTighten the direct new-function argument cleanup so it bails out when the constructor body may reach the current function object or dynamically observe invocation arguments. This includes lexical `arguments`, eval, with, `this`, referenced function-expression identifiers, new.target, rest parameters, and spread argument lists.\n\nAdd fixture and execution coverage for the observed argument-list cases.

skku970412:fix-new-expr-useless-args-11684

7 hours ago

fix(es/minifier): preserve spread args in new function expr Spread arguments have dynamic runtime arity, so a syntactic trailing argument after a spread cannot be classified as unused based only on the formal parameter count.\n\nSkip the new-function argument cleanup whenever the NewExpr argument list contains a spread, and add fixture plus execution coverage for a spread-before-trailing-argument case.

skku970412:fix-new-expr-useless-args-11684

8 hours ago

fix(react-compiler): Remove React-like prefilter (#12007) **Description:** Remove SWC's React-like function prefilter and defer compilation eligibility to React Compiler. The prefilter duplicates React Compiler policy and rejects source before the compiler can evaluate it. For example: ```jsx function createFoo() { return function Foo() { "use memo"; return <div>hello, world</div>; }; } ``` React Compiler's Babel integration compiles the annotated inner function, but SWC previously returned the source unchanged because `createFoo` did not look React-like and the prefilter intentionally did not inspect nested function bodies. This pattern is not necessarily a React-blessed use of the directive nor is it conventional React. Regardless, the SWC adapter should not impose a stricter eligibility policy or limit valid uses of the React Compiler API. React Compiler should remain responsible for deciding what to compile. This PR removes the React-like heuristic while retaining the separate guard for unsupported resource-management declarations. It also adds a fixture covering the nested directive case. **Related issue (if exists):** N/A **Verification:** - `cargo fmt --all` - `cargo test -p swc_ecma_react_compiler` - `cargo clippy --all --all-targets -- -D warnings` --- _Prepared with assistance from OpenAI Codex 🤖._

main

10 hours ago

Merge branch 'main' into jordant/remove-react-prefilter

imjordanxd:jordant/remove-react-prefilter

10 hours ago

feat(test262): harden conformance runtime

refactor/test262

13 hours ago

refactor: remove direct rkyv dependencies (#12010) ## Summary - Remove SWC's direct `rkyv`, `bytecheck`, and `rancor` dependencies and archive implementations. - Keep plugin serialization on CBOR and refresh path-based plugin fixture lockfiles. - Retain only transitive rkyv usage from Wasmer and lightningcss. ## Validation - `cargo fmt --all` - `cargo clippy --all --all-targets -- -D warnings` - `cargo test` for all changed Rust crates - Plugin and host feature checks --- Closes https://github.com/swc-project/swc/issues/11991

main

15 hours ago

Latest Branches

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fix(es/minifier): drop pure extra args of new function expr#12012

6 hours ago

d8539e7

skku970412:fix-new-expr-useless-args-11684

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fix(react-compiler): Remove React-like prefilter#12007

10 hours ago

9dccf65

imjordanxd:jordant/remove-react-prefilter

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feat(test262): add official Test262 conformance runner#12011

13 hours ago

55a2f22

refactor/test262

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