perf: return impl ExactSizeIterator from slice-backed accessors#10133
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These accessors are already `ExactSizeIterator` internally — the `impl Iterator` return type just erased it. Widening to `impl ExactSizeIterator` lets callers pre-size collections from the known length (`Vec::with_capacity(iter.len())`) instead of growing through reallocs, and lets them call `.len()` directly. Backward-compatible: `ExactSizeIterator: Iterator`, so existing callers are unaffected. | accessor | backing | |---|---| | `ChunkGraph::sorted_chunks` | `Vec<ChunkIdx>::iter().map(..)` | | `PluginDriver::iter_plugin_with_context_by_order` | `&[PluginIdx]::iter().copied().map(..)` | | `StmtInfos::iter_enumerated_without_namespace_stmt` | `IndexVec::iter_enumerated().skip(1)` (`Skip` preserves the exact len) | | `HybridIndexVec::iter` | `Either<IndexVec::iter(), FxHashMap::values()>` (both arms `ExactSizeIterator`) | | `ScanMode::iter` | `Either<iter::empty(), slice::iter()>` (both arms `ExactSizeIterator`) | | `DependedRuntimeHelperMap::iter` | `[Vec<_>; N]::iter().enumerate().map(..)` | The rest of the crate's `impl Iterator` accessors are correctly left alone — they use `filter_map` / `flat_map` / custom iterators that erase the length. Same idea as oxc-project/oxc#24144.
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## [1.1.5] - 2026-07-08 ### 🚀 Features - detect top-level import-binding reads as execution-order sensitive (#10180) by @hyf0 - sourcemap_filenames: add a sourcemapFileNames option (#9271) by @V1OL3TF0X - binding: record plugin hook result kind in tracing spans (#10154) by @IWANABETHATGUY - linking: skip side-effect-free modules in per-entry reachability (#10111) by @IWANABETHATGUY - improve error message for unresolved virtual imports (#10156) by @sapphi-red - add descriptive metadata to plugin API (#10106) by @sapphi-red - add `--configLoader=native` option (#10118) by @sapphi-red ### 🐛 Bug Fixes - improve invalid annotation warnings (#10185) by @hyf0 - keep deduplicated asset filenames stable once they can be observed (#10191) by @shulaoda - sourcemap_filenames: use public option name in pattern errors (#10188) by @IWANABETHATGUY - sourcemap_filenames: hash prepared sourcemap content (#10178) by @hyf0 - tree-shake unused circular declarators exported via export list (#10166) by @IWANABETHATGUY - dev: don't panic when an HMR rebuild hits an unresolved import (#10162) by @shulaoda - propagate errors from output.globals function (#9880) by @shulaoda - dev: revert cache mutations when a partial scan fails (#10110) by @shulaoda - dev: update importer relationships of cached modules in incremental build (#10107) by @shulaoda - hmr: fall back to full reload when a changed module is not registered as executed (#10132) by @shulaoda - chunk-optimizer: follow entry facade edges in runtime placement cycle check (#10101) by @hyf0 - dev: ignore watcher events after close (#10113) by @hyf0 - emit async wrapper for TLA modules under onDemandWrapping (#10086) by @IWANABETHATGUY - gate sideEffects:false modules' side effects on body demand (#10080) by @IWANABETHATGUY - rolldown_plugin_vite_resolve: return empty object for `browser: false` mapped modules (#10082) by @sapphi-red - reset the word-boundary state on newline in Hires::Boundary sourcemaps (#10025) by @shulaoda - trim an emptied chunk's outro/intro instead of skipping past it (#10029) by @shulaoda - test each edited chunk's own start against indent exclude ranges (#10026) by @shulaoda - preserve sourcemap mappings for indented lines when a CJS module shares the chunk (#10074) by @hyf0 ### 🚜 Refactor - separate tree-shaking side effects from execution order sensitivity (#10168) by @hyf0 - type construct_vite_preload_call to take an ObjectPattern (#10135) by @shulaoda - treeshake: single-source the own-export classification shared with the lazy-barrel loader (#10098) by @IWANABETHATGUY - dev: reuse Vite's bundledDev server (#10081) by @h-a-n-a - clippy: ban std HashMap/HashSet in favour of FxHashMap/FxHashSet (#10108) by @Boshen - treeshake: make body demand a second module bit instead of a stmt multimap (#10097) by @IWANABETHATGUY - seal used_symbol_refs by construction after its last writer (#10091) by @hyf0 - treeshake: replace inclusion mutual recursion with a worklist engine (#10096) by @IWANABETHATGUY - treeshake: split include_statements.rs into focused modules (#10095) by @IWANABETHATGUY - drop redundant is_user_defined filter on partitioned entries (#10050) by @shulaoda - project the retained export interface out of used_symbol_refs (#10089) by @hyf0 - track used external symbols separately from used_symbol_refs (#10088) by @hyf0 - make module namespace inclusion an explicit linking metadata field (#10087) by @hyf0 - rename statement evaluation metadata (#10078) by @hyf0 ### 📚 Documentation - virtual modules user-facing id convention (#10155) by @sapphi-red - cli: clarify disabling boolean/object flags like codeSplitting (#10153) by @IWANABETHATGUY - chore: remove Vite+ alpha banner (#10105) by @mdong1909 - write down the used_symbol_refs contract (#10090) by @hyf0 - dev/lazy: update design and implementation (#10079) by @h-a-n-a ### ⚡ Performance - ast_scanner: stop order-sensitivity checks once a module is flagged (#10190) by @IWANABETHATGUY - return impl ExactSizeIterator from slice-backed accessors (#10133) by @Boshen - binding: box dev and watcher napi futures (#10103) by @Boshen ### 🧪 Testing - move string_wizard replace unit tests to the JS magic-string suite (#10176) by @IWANABETHATGUY - dev: assert incremental scan state matches a fresh full build after each HMR step (#10115) by @shulaoda - dev: restore runtime assertions of delete_file_not_used_anymore (#10112) by @shulaoda - dev: fix flaky dev server tests in CI (#10152) by @h-a-n-a - add regression test for #10099 (lazyBarrel drops default-import binding but keeps its property reads) (#10109) by @IWANABETHATGUY ### ⚙️ Miscellaneous Tasks - deploy website to Void via GitHub OIDC (#10192) by @Boshen - deps: update oxc to 0.139.0 (#10161) by @shulaoda - deps: update test262 submodule for tests (#10160) by @rolldown-guard[bot] - rolldown_plugin_utils: remove dead asset-url and css scaffolding (#10131) by @shulaoda - deps: revert vite-plus to v0.2.1 (#10148) by @shulaoda - deps: update github actions (#10141) by @renovate[bot] - deps: update dependency rust to v1.96.1 (#10145) by @renovate[bot] - deps: update npm packages (#10142) by @renovate[bot] - deps: update rust crates (#10143) by @renovate[bot] - deps: update napi to v3.10.3 (#10121) by @renovate[bot] - rolldown_utils: remove unused time module (#10138) by @shulaoda - remove dead CopyModulePlugin::is_active method (#10129) by @shulaoda - remove dead LazyCompilationContext::is_lazy_module method (#10128) by @shulaoda - remove dead BuildDiagnostic::downcast_ref method (#10127) by @shulaoda - deps: update dependency vite-plus to v0.2.2 (#10084) by @renovate[bot] - deps: update rust crate oxc_sourcemap to v8.1.0 (#10122) by @renovate[bot] - deps: update crate-ci/typos action to v1.48.0 (#10124) by @renovate[bot] - enable more clippy restriction lints (#10114) by @Boshen - deps: update rust dependencies (#10100) by @Boshen - deps: update oxc resolver to v11.23.0 (#10083) by @renovate[bot] ###◀️ Revert - Revert "chore(deps): revert vite-plus to v0.2.1" (#10157) by @h-a-n-a - "fix(hmr): fall back to full reload when a changed module is not registered as executed (#10132)" (#10151) by @shulaoda ### ❤️ New Contributors * @V1OL3TF0X made their first contribution in [#9271](#9271) Co-authored-by: shulaoda <[email protected]>
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These accessors are already
ExactSizeIteratorinternally — theimpl Iteratorreturn type just erased it. Widening toimpl ExactSizeIteratorlets callers pre-size collections from the known length (Vec::with_capacity(iter.len())) instead of growing through reallocs, and lets them call.len()directly. Backward-compatible:ExactSizeIterator: Iterator, so existing callers are unaffected.ChunkGraph::sorted_chunksVec<ChunkIdx>::iter().map(..)PluginDriver::iter_plugin_with_context_by_order&[PluginIdx]::iter().copied().map(..)StmtInfos::iter_enumerated_without_namespace_stmtIndexVec::iter_enumerated().skip(1)(Skippreserves the exact len)HybridIndexVec::iterEither<IndexVec::iter(), FxHashMap::values()>(both armsExactSizeIterator)ScanMode::iterEither<iter::empty(), slice::iter()>(both armsExactSizeIterator)DependedRuntimeHelperMap::iter[Vec<_>; N]::iter().enumerate().map(..)The rest of the crate's
impl Iteratoraccessors are correctly left alone — they usefilter_map/flat_map/ custom iterators that erase the length.Same idea as oxc-project/oxc#24144.