perf: avoid intermediate Strings in the ESM export clause#9644
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IWANABETHATGUY
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Rendering the ESM `export { ... }` clause collected items into a `Vec`, `join`ed them into a temporary `String`, wrapped that in another `concat_string!` `String`, and built a per-item `concat_string!` for each namespace-alias `var` declaration — all just to `push_str` into the output buffer.
Write the var declarations and the export clause directly into the output `String`. Output bytes are identical.
Behavior-preserving. Covered by the existing snapshot suite. Scope: the ESM branch; the CJS/IIFE/UMD `join("\n")` paths are left as-is.
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## [1.1.1] - 2026-06-11 ### 🚀 Features - ecmascript_utils: introduce AstFactory for AST construction (#9682) by @hyf0 - drop no-op init calls for empty wrapped-ESM modules (#9678) by @IWANABETHATGUY ### 🐛 Bug Fixes - resolver: honor package.json#type for .jsx/.tsx extensions (#9690) (#9699) by @IWANABETHATGUY - hmr: report the full-reload reason for the invalidate-loop case (#9708) by @hyf0 - explicit `moduleSideEffects` from a hook must take priority over the `package.json#sideEffects` (#9688) by @sapphi-red - keep the `rolldown-runtime` name for the standalone runtime chunk (#9685) by @shulaoda - lazy-barrel: request all exports for entry barrels on first encounter (#9672) by @shulaoda - finalizer: skip init_*() for tree-shaken wrapped ESM owners (#9669) by @IWANABETHATGUY - order `chunk.imports` by execution order (#9654) by @chuganzy - vite-resolve: preserve slash separators for Sass partial exports (#9546) by @cjc0013 - cross-chunk CJS wrapper shadowed by author-local binding (#9648) by @IWANABETHATGUY ### 🚜 Refactor - precompute wrapped-ESM init metadata in generate stage (#9712) by @IWANABETHATGUY - ecmascript_utils: fold construction ext traits onto AstFactory and delete AstSnippet (#9702) by @hyf0 - finalizer: finish ScopeHoistingFinalizer migration to AstFactory (#9701) by @hyf0 - finalizer: migrate module_finalizers/mod.rs to AstFactory (#9700) by @hyf0 - hmr: migrate hmr finalizer to AstFactory (#9695) by @hyf0 - plugin: migrate vite_build_import_analysis to AstFactory (#9693) by @hyf0 - scanner: migrate tweak_ast_for_scanning to AstFactory (#9683) by @hyf0 - always split runtime module first (#9419) by @IWANABETHATGUY ### 📚 Documentation - tsconfig: correct auto-discovery resolution to match TypeScript (#9714) by @shulaoda - design: plan to unify all internal AST construction (#9673) by @hyf0 - tsconfig: align reference resolution docs with TypeScript behavior (#9641) by @shulaoda ### ⚡ Performance - avoid per-module join Strings in scope-hoisting concatenation (#9645) by @Boshen - avoid intermediate Strings in the ESM export clause (#9644) by @Boshen - reuse a scratch buffer for facade namespace names in the scanner (#9642) by @Boshen - reuse the import-matching tracker stack across named imports (#9643) by @Boshen - avoid cloning the per-chunk export-items map in render_chunk_exports (#9639) by @Boshen - avoid CompactStr allocation in sorted-exports membership check (#9640) by @Boshen ### 🧪 Testing - add more `moduleSideEffects` precedence tests (#9689) by @sapphi-red - 9651: drop shimMissingExports from regression fixture (#9674) by @IWANABETHATGUY ### ⚙️ Miscellaneous Tasks - update react repo links (#9711) by @iiio2 - remove outdated pnpm configurations (#9666) by @btea - deps: update github actions to v2.81.5 (#9665) by @renovate[bot] - testing: migrate test harness off deprecated inlineDynamicImports (#9710) by @IWANABETHATGUY - hmr: delete commented-out dead code left from old register-module codegen (#9707) by @hyf0 - deps: update napi-rs toolchain (#9706) by @shulaoda - deps: update rollup submodule for tests to v4.61.1 (#9676) by @rolldown-guard[bot] - deps: update test262 submodule for tests (#9677) by @rolldown-guard[bot] - deps: update oxc to 0.135.0 (#9670) by @Boshen - pass ALGOLIA_APP_ID and ALGOLIA_API_KEY to void deploy (#9667) by @Boshen - deps: update github actions (#9662) by @renovate[bot] - deps: update rust crates (#9663) by @renovate[bot] - deps: update rolldown-plugin-dts to v0.25.2 (#9661) by @renovate[bot] - deps: update typos to v1.47.2 (#9660) by @renovate[bot] - deps: update docs dependencies (#9657) by @bddjr - deps: update typos to v1.47.1 (#9655) by @renovate[bot] - deploy website in its own workflow, only on docs output change (#9650) by @Boshen - publish to pkg.pr.new add pm and `commentWithDev` option (#9638) by @btea ### ❤️ New Contributors * @chuganzy made their first contribution in [#9654](#9654) * @cjc0013 made their first contribution in [#9546](#9546)
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Rendering the ESM
export { ... }clause collected items into aVec,joined them into a temporaryString, wrapped that in anotherconcat_string!String, and built a per-itemconcat_string!for each namespace-aliasvardeclaration — all just topush_strinto the output buffer.Write the var declarations and the export clause directly into the output
String. Output bytes are identical.Behavior-preserving. Covered by the existing snapshot suite. Scope: the ESM branch; the CJS/IIFE/UMD
join("\n")paths are left as-is.