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test(es/parser): Keep the module-only Flow fixture out of `tests/flow` `swc_ecma_transforms_typescript` reparses every `tests/flow` fixture with `parse_file_as_program`, which still rejects a top-level `for await` in Flow (the Hermes corpus requires this). The module-only fixture failed that test in CI. Move it to `tests/flow-module`, which is parsed with `parse_module` only, and add a `tests/flow` fixture where `for await` follows an `import`, which is valid under `parse_program`. Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

kdy1/fix-issue-12749

7 hours ago

perf(es/minifier): Avoid repeated simplification of unused values (#12736)   **Description:** Duplicate simplification caused exponential work in nested IIFEs and spread arrays. Simplify only tail returns before conversion and let the return traversal handle the rest. Keep spread arrays after reducing their ordinary elements so iterators are consumed without revisiting nested expressions.  **BREAKING CHANGE:**  **Related issue (if exists):** - Close swc-project/swc-ai-issues#71 - Close swc-project/swc-ai-issues#73 Co-authored-by: Donny/강동윤 <kdy.1997.dev@gmail.com>

main

7 hours ago

fix(es/parser): Export `TokenFlags` from `unstable` (#12751) **Description:** The public `Tokens` trait uses `TokenFlags` in `update_token_flags` and `token_flags`. `TokenFlags` was private to the crate. Because of this, no crate outside the parser could implement `Tokens`. This PR exports `TokenFlags` from `swc_ecma_parser::unstable`, next to the other token types. It also adds an integration test. The test wraps `Lexer` in a `Tokens` implementation from outside the crate and parses a module with it. Local validation: `cargo test -p swc_ecma_parser` passed. `cargo test -p swc_ecma_parser --features unstable --test unstable_tokens` passed. `cargo clippy -p swc_ecma_parser --all-targets --features unstable -- -D warnings` passed. I did not run the workspace-wide `cargo clippy --all`. CI has not run yet. **BREAKING CHANGE:** None. **Related issue (if exists):** Closes #12747 Co-authored-by: mellyeliu <64865235+mellyeliu@users.noreply.github.com> Co-authored-by: Claude Sonnet 5.5 <noreply@anthropic.com>

main

10 hours ago

fix(es/parser): Allow private brand checks in Flow mode (#12752) **Description:** Flow mode rejected every `#name` inside an expression. This also rejected the valid private brand check `#x in o`, which failed with `Expected an identifier`. Now Flow mode accepts `#name` only as the direct left operand of an `in` that binds tighter than the enclosing operator. This is the rule Babel uses. `#x;`, `(#x) in o`, `-#x in o` and `1 + #x in o` still error, so the Hermes behavior from #11699 is kept. Tests: new Flow fixtures cover the valid brand checks (`#x in o`, `o != null && #x in o`, `true == #x in o`) and the four invalid positions. I ran `cargo test -p swc_ecma_parser --all-features` (all passed, including the Hermes parity tests), `cargo fmt --all` and `cargo clippy -p swc_ecma_parser --all-targets --all-features -- -D warnings` (clean) on the final code. I did not run the workspace-wide clippy. **BREAKING CHANGE:** None. **Related issue (if exists):** Closes #12748 --------- Co-authored-by: mellyeliu <64865235+mellyeliu@users.noreply.github.com> Co-authored-by: Claude Sonnet 5.5 <noreply@anthropic.com>

main

10 hours ago

fix(es/parser): Export `TokenFlags` from `unstable` The public `Tokens` trait uses `TokenFlags` in `update_token_flags` and `token_flags`, but the type was private. Crates outside the parser could not implement `Tokens`. Export it from `swc_ecma_parser::unstable` next to the other token types. Co-authored-by: mellyeliu <64865235+mellyeliu@users.noreply.github.com> Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

kdy1/fix-issue-12747

11 hours ago

Merge branch 'main' into perf/minifier-pure-traversal

perf/minifier-pure-traversal

11 hours ago

chore: Add changeset Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

kdy1/fix-issue-12748

11 hours ago

fix(es/parser): Allow top-level `for await` in Flow modules The Flow-only `for await` check in `parse_for_stmt` also ran under `parse_module`, so `for await (const x of y) {}` at the top level of a module failed to parse. Top-level await makes this valid in modules, so skip the check when the module context is active. Scripts, regular functions and static blocks still report an error. Fixes #12749 Co-authored-by: mellyeliu <64865235+mellyeliu@users.noreply.github.com> Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

kdy1/fix-issue-12749

11 hours ago

Latest Branches

-4%

fix(es/parser): Allow top-level `for await` in Flow modules#12750

7 hours ago

40282b3

kdy1/fix-issue-12749

0%

fix(es/parser): Export `TokenFlags` from `unstable`#12751

11 hours ago

e432385

kdy1/fix-issue-12747

0%

perf(es/minifier): Avoid repeated simplification of unused values#12736

11 hours ago

18870ae

perf/minifier-pure-traversal

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