refactor: readability follow-ups to the ReplaceWith migration#10286
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Follow-ups to #10285. No behavior change. - Fold two `matches!` + `let ... else { unreachable!() }` pairs in the module finalizer into plain `if let`. Inside a `replace_with` closure that shape is unavoidable, but `top_stmt` is an owned local, so the second discriminant test and its `unreachable!()` were ceremony. - Reword the HMR catch-all comment. Flattening the nested match merged the TypeScript-only arm with the uncommented `_` arm, and only the TypeScript comment survived, so it now describes a rare case instead of what the arm really catches. - Re-indent the `exports.extend` closure in the HMR finalizer. rustfmt bails out on it, so `cargo fmt --check` never caught that its body was stranded well right of its header. At the shallower nesting it fits again. - Use `first()` instead of `first_mut()` in `json_object_expr_to_esm`, and drop an `.expect()` that re-checked an invariant established a few lines above.
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## [1.2.0] - 2026-07-15 ### 🚀 Features - dev: skip shipping factories for newly imported top-level modules (#10223) by @h-a-n-a - dev: per-client ship map for HMR patch sizing (#10208) by @h-a-n-a - dev: client-side HMR (#10164) by @h-a-n-a - dev: send a full-reload update to clients when a tsconfig changes (#10262) by @shulaoda - treat `import.meta['url']` and `import.meta['ROLLUP_FILE_URL_*']` as side-effect free (#10267) by @sapphi-red - rewrite `import.meta['url']` (#10251) by @sapphi-red - add `FILE_NOT_FOUND` error (#10220) by @sapphi-red - treat `import.meta.ROLLUP_FILE_URL_*` as side-effect free (#10217) by @sapphi-red ### 🐛 Bug Fixes - sourcemap: preserve unmapped boundaries during composition (#10254) by @hyfdev - `[format]` in `*FileNames` option for ESM format should be `es` instead of `esm` (#10214) by @sapphi-red - sourcemap: preserve coarse mappings during composition (#10249) by @hyfdev - rolldown_plugin_vite_import_glob: support tsconfig paths with `import.meta.glob` (#10167) by @sapphi-red - dev: clear tsconfig caches for bare full builds (#10276) by @shulaoda - dev: force a full rebuild when a tsconfig changes (#10261) by @shulaoda - treat rooted drive-less module ids as absolute in preserveModules naming (#10235) by @IWANABETHATGUY - watch: rebuild when tsconfig files change (#10258) by @shulaoda - watch: drop tsconfig-merged transform options on each rebuild (#10257) by @shulaoda - incorrect `EMPTY_IMPORT_META` warning for `import.meta.ROLLUP_FILE_URL_*` for CJS output (#10221) by @sapphi-red - deconflict: rename CJS locals shadowing wrapped-ESM namespace objects (#9970) by @IWANABETHATGUY - rolldown: drop the unused runtime module after entry-level external flattening (#10237) by @IWANABETHATGUY - rolldown: re-propagate has_dynamic_exports to transitive star importers (#10239) by @IWANABETHATGUY - tree-shaking: tree-shake destructured dynamic import namespace bindings (#10213) by @logaretm - s390x: use json-escape-simd 3.1.1 for big-endian JSON escaping fix (#10211) by @satyamg1620 ### 🚜 Refactor - dev: move full-reload to client side (#10207) by @h-a-n-a - readability follow-ups to the ReplaceWith migration (#10286) by @IWANABETHATGUY - replace take_in-then-write-back with ReplaceWith and by-value moves (#10285) by @Boshen - share the main resolver's cache with the transformer's tsconfig lookups (#10205) by @shulaoda - rolldown: extract the ns star-external __reExport emission rule into LinkingMetadata (#10238) by @IWANABETHATGUY - rolldown: unify link/generate diagnostics into a Diagnostics accumulator (#10234) by @IWANABETHATGUY - sourcemap_filenames: drop dead sourcemap-filename plumbing (#10189) by @IWANABETHATGUY - extract external import symbol merging into a method (#10224) by @IWANABETHATGUY - rolldown: skip CJS namespace merging under strict execution order (#10203) by @hyfdev - resolve the manual tsconfig per file instead of once at startup (#10200) by @shulaoda - rolldown: route interop ESM init emission through a shared init-target view (#10202) by @hyfdev - rolldown: collapse vestigial wrap-kind state and share chunk sort helper (#10201) by @hyfdev ### 📚 Documentation - show plugin kinds in JSDoc and each hook's description (#10218) by @sapphi-red - add an explanation about removing imports from external modules without any messages (#10215) by @sapphi-red ### ⚡ Performance - sourcemap: owned merge in SourceJoiner::join (4005->5 allocs/chunk) (#10250) by @Boshen - avoid redundant sourcemap string copies in collapse and minify paths (#10093) by @Boshen ### 🧪 Testing - code-splitting: establish strict-order review baselines (#10287) by @hyfdev - dev: add hot API test cases (#10181) by @h-a-n-a - code-splitting: normalize strict execution order variants (#10277) by @hyfdev - code-splitting: harden strict execution order coverage (#10252) by @hyfdev - code-splitting: add strict execution order regressions (#10253) by @hyfdev ### ⚙️ Miscellaneous Tasks - deps: update github actions (#10241) by @renovate[bot] - deps: update oxc to 0.140.0 (#10274) by @shulaoda - update Yunfei's GitHub username (#10275) by @hyfdev - deps: update napi (#10260) by @renovate[bot] - deps: update test262 submodule for tests (#10266) by @rolldown-guard[bot] - deps: update dependency vite-plus to v0.2.4 (#10256) by @renovate[bot] - deps: update napi (#10240) by @renovate[bot] - deps: update oxc resolver to v11.24.2 (#10245) by @renovate[bot] - deps: update rust crates (#10244) by @renovate[bot] - disable Renovate updates for idna_adapter (#10248) by @shulaoda - deps: update oxc resolver to v11.24.1 (#10232) by @renovate[bot] - deps: update rust crate oxc_sourcemap to v8.1.1 (#10233) by @renovate[bot] - deps: update dependency rolldown-plugin-dts to ^0.27.0 (#10206) by @renovate[bot] - deps: upgrade sugar_path to v3 (#10230) by @hyfdev - add `dist-*` to `.gitignore` in sourcemap-filenames/hash-final-content fixture (#10216) by @sapphi-red - deps: update dependency rust to v1.97.0 (#10209) by @renovate[bot] ### ❤️ New Contributors * @satyamg1620 made their first contribution in [#10211](#10211) Co-authored-by: shulaoda <[email protected]>
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What
Readability follow-ups to #10285, which migrated the
take_in-then-write-back patterns toReplaceWith. No behavior change — this only touches how the code reads.How
matches!(…)+let … else { unreachable!() }→if let(module finalizer, ×2: theexport defaultarm and thetop_level_varclass rewrite).Inside a
replace_withclosure that double-destructure is unavoidable — the closure is handed the whole node, so it has to re-narrow, and that's the shape oxc's own docs use. Buttop_stmtis a plain owned local.if letmoves the binding out only when the pattern matches, and every arm there already reassignstop_stmtor returns, so the second discriminant test and itsunreachable!()were pure ceremony. Two of them go away.Say what the HMR catch-all arm actually does. refactor: replace take_in-then-write-back with ReplaceWith and by-value moves #10285 flattened the inner
match module_declinto the outermatch node, which merged two arms: one catching onlyTSExportAssignment/TSNamespaceExportDeclaration(carrying the TypeScript comment), and an uncommented_catching everything else. Only the TypeScript comment survived the merge, so the arm now reads as though it is about TypeScript when in practice nearly everything reaching it is an ordinary statement.Re-indent the
exports.extendclosure in the HMR finalizer. rustfmt bails out on this expression, so its body had been stranded ~11 columns right of its header since before refactor: replace take_in-then-write-back with ReplaceWith and by-value moves #10285, and the flattening widened that to ~15.cargo fmt --checkpasses either way, so CI never flagged it. At the shallower nesting the block now fitsmax_width, so rustfmt formats it again instead of giving up — it should stop drifting.first_mut()→first()injson_object_expr_to_esm, now that the binding is only read; the two-step destructure folds into onelet … else.Drop
.expect("init is checked to beSomeabove")intry_inline_json_module_prop. It re-checked at runtime an invariant established a few lines above, and only existed to dodge a&mutthat theSomearm no longer needs. Each arm now readsfirst_decl.initdirectly.Tests
No new tests. Nothing here changes behavior, so there is no test that would fail before and pass after.
What needs checking is that the output is unchanged, and the snapshot suite is the check for that — but it auto-accepts (as
just test-updateputs it: "Rust tests will update snapshots automatically"), so a green run proves nothing by itself. The real check is what the working tree looks like afterwards:cargo test -p rolldown→ 1869 passed, and zero.snapfiles modified.cargo clippy -p rolldown --all-targets -- --deny warningsandcargo fmt --all --checkboth clean.