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fix(react-compiler): refine conservative fast check

marcoshernanz:agent/react-compiler-conservative-fast-check

43 minutes ago

Potential fix for pull request finding Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

mattcosta7:copilot/update-source-map-emission

8 hours ago

test(es/typescript): Cover const initializers under mutable enums Extends the existing `ts_enum_is_mutable_true` case with both sides of the guard: a const initialized from a mutable enum member, which must stay a runtime read, and one from a `const enum` member, which still folds. Both fail on main — the first because the value was folded away, the second because it was not folded at all.

baltasarblanco:fix/11715-ts-enum-const-var-folding

20 hours ago

perf(es/typescript): Skip const initializers that cannot be constant `compute` takes the initializer by value, so the collection pass cloned every `const` initializer in the program, while most of them hit the `Opaque` catch-all right away: in real TypeScript they are mostly arrow functions, object literals and calls. Check the outermost form before cloning. `es/transform/baseline/common_typescript` goes from 59.6 us back to 53.3 us, against 53.3 us on main. No test output changes.

baltasarblanco:fix/11715-ts-enum-const-var-folding

1 day ago

test(es/typescript): Update constEnum2 tsc reference `g = CONST` now resolves to a constant, so the member is inlined and no longer emitted, matching how `d = 10` is already handled in the same `const enum`. The remaining members stay opaque because they call `Math.random()`.

baltasarblanco:fix/11715-ts-enum-const-var-folding

1 day ago

chore: Add changeset

baltasarblanco:fix/11715-ts-enum-const-var-folding

1 day ago

fix(flow): preserve component semantics without AST break

fix/flow-component-type-semantics

2 days ago

fix(plugin/runner): write Wasmer cache atomically (#12100) **Description:** This fixes intermittent Wasmer plugin cache corruption when multiple processes compile the same plugin concurrently. The Wasmer backend previously serialized modules directly to the final cache path. Parallel Jest, Turbo, or Nx workers could observe the file after its metadata header was written but before the complete artifact was available, producing `metadata_len` slice-bound failures. The backend now serializes the module in memory, writes it to a unique temporary file in the cache directory, and atomically renames the completed file into place. A concurrent-writer regression test verifies that readers only observe complete cache artifacts. **Related issue (if exists):** Fixes #6467 **Validation:** - `cargo test -p swc_plugin_backend_wasmer` - `cargo fmt --all` - `cargo clippy --all --all-targets -- -D warnings`

main

2 days ago

Latest Branches

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feat(react-compiler): add conservative fast check#12105

2 hours ago

8cacc00

marcoshernanz:agent/react-compiler-conservative-fast-check

0%

fix(es/react-compiler): recover source map spans from locations#12104

8 hours ago

022c7ad

mattcosta7:copilot/update-source-map-emission

-2%

fix(es/typescript): Treat const variable references as enum constants#12101

21 hours ago

2e8749f

baltasarblanco:fix/11715-ts-enum-const-var-folding

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