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Latest Results

fix(es/parser): preserve type references named asserts before line breaks

fix/parser-asserts-linebreak

6 minutes ago

perf(es/preset-env): Reduce binary size with browserslist deflate (#12381) **Description:** Reduce the native binary size by upgrading `browserslist-rs` from 0.20.0 to 0.21.2 and explicitly enabling `deflate` for its bundled browser data. `@swc/core` `.node` release size on `aarch64-apple-darwin`: | Configuration | Bytes | MiB | | --- | ---: | ---: | | browserslist-rs 0.20.0 | 26,662,128 | 25.43 | | browserslist-rs 0.21.2 + deflate | 24,185,488 | 23.07 | | Reduction | **2,476,640** | **2.36 (9.29%)** | Both builds used `cargo build --release --locked -p binding_core_node`, default features (`swc_v1`, `plugin`), the repository toolchain (`nightly-2026-04-10`), and the unchanged release profile (fat LTO, stripped symbols, one codegen unit, panic abort). The baseline is `baf0ba6ee4`; both builds used the same checkout path. These are raw native library sizes and measure the combined version upgrade and deflate change. Both `.node` libraries loaded through the `@swc/core` JavaScript API and produced identical outputs for six browser-target queries, including `supports`, regional usage, and baseline queries. **BREAKING CHANGE:** For Rust consumers, `BrowserData::parse_versions` now accepts `browserslist::Distrib` from browserslist-rs 0.21 instead of 0.20, also exposed through `swc_core::ecma::preset_env`. The changeset marks `preset_env_base` and `swc_core` as major. **Related issue (if exists):** - [browserslist-rs v0.21.2 release notes](https://github.com/browserslist/browserslist-rs/releases/tag/v0.21.2) - [#50: Drop derivable caniuse data](https://github.com/browserslist/browserslist-rs/pull/50) - [#52: Compress data using deflate](https://github.com/browserslist/browserslist-rs/pull/52) - [#53: Deflate more data](https://github.com/browserslist/browserslist-rs/pull/53) - [#54: Improve deflate binary size](https://github.com/browserslist/browserslist-rs/pull/54)

main

22 minutes ago

fix(es/parser): preserve type references named asserts before line breaks

fix/parser-asserts-linebreak

44 minutes ago

chore: Add changeset

chenjiahan:chenjiahan/browserslist-deflate

57 minutes ago

fix(es/parser): allow string import and export names after type (#12371) **Description:** Fix valid TypeScript imports and exports being rejected when `type` appears alongside a quoted name: ```typescript export { type as "" }; import { type "name" as T } from "mod"; ``` The parser now recognizes when `type` is a variable name and when it marks a type-only import or export. This keeps value imports and exports in the generated JavaScript while removing type-only ones.

main

7 hours ago

test(es/lexer): remove dedicated tuple parser tests

fix/parser-mixed-tuple-elements

7 hours ago

fix(es/parser): correctly round non-decimal numeric literals (#12370) **Description:** Large binary, octal, and hexadecimal numeric literals could lose precision during parsing and produce incorrect AST values. Round these literals once to the nearest representable Number, including legacy octal literals.

main

7 hours ago

fix(es/parser): isolate constructor function contexts (#12367) **Description:** Allow constructors to use `await` as an identifier in scripts when nested in async functions or async arrow parameters, and to access their own `arguments` when nested in class fields or static blocks. Previously, inherited outer contexts could reject these inputs or parse an `await(...)` call as an await expression.

main

8 hours ago

Latest Branches

fix(es/parser): preserve type references named asserts before line breaks#12372

47 minutes ago

e9e1bd7

fix/parser-asserts-linebreak

perf(es/preset-env): Reduce binary size with browserslist deflate#12381

1 hour ago

c7b817e

chenjiahan:chenjiahan/browserslist-deflate

fix(es/parser): recognize named optional and rest tuple elements#12368

7 hours ago

210c062

fix/parser-mixed-tuple-elements

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