[robobun]

Fixes #8993

Problem

• bun build gives two bundles from the same sources: a file imported by directory and by path is kept in 5 to 16 of 40 builds on main.
• Resolver::finalize_result (src/resolver/resolver.rs:1597) reads sideEffects from the package.json of the import route. The bundler keys a module by its path and keeps the first answer.
• For a module/main pair, the main pass overwrites the answer: Bun.build does not seem to include all imports #8993, TypeError: undefined is not an object (evaluating 'env().platform.isTypedArray').

Fix

• finalize_result reads sideEffects for the file that the import resolves to, from the nearest package.json above it that has a name or a sideEffects field.
• Merge bundler: turn automatic barrel mode off for --ignore-dce-annotations and for the bun test --changed scan #45938 (the fourth commit, unchanged) and bundler: make each read of a run-time export * name depend on the barrel's exports object #46903 (the linker change for Bun build does not import values re-exported from another package when sideEffects is false #18008) first.
• Verified: 63 cases in dce.test.ts, tsconfig.test.ts, bundler_barrel.test.ts, test-changed.test.ts (47 fail on main).
• Self-reviewed: 15 concerns raised, 13 addressed (Notes).

Background

• The barrel pass skips the unused re-exports of an index file that sideEffects: false covers.
• In esbuild a nested { "type": "module" } package.json hides the package's sideEffects. Here it does not: that rule makes 43 of 61 cached packages larger. A fixed winner in the bundler was also weighed: each route alone still differs.

Downsides

• A package.json with no name now decides for relative imports, as in esbuild: import "./polyfill" below { "sideEffects": false } is dropped. Without bundler: make each read of a run-time export * name depend on the barrel's exports object #46903, 5 such layouts that work on main throw (Bun build does not import values re-exported from another package when sideEffects is false #18008).
• bun add --analyze misses a package behind an unused re-export there, as below a named package.json on main.
• DirInfo grows 8 B.

Notes

One file, two import routes (file kept in N of 40 builds: path import alone / directory import alone / both, directory first / both, path first)

Shape	main	this PR	esbuild 0.25.1
nameless sub-package.json, sideEffects: false, module + main (@heroicons/react/outline)	40 / 40 / 40 / 40	0 / 0 / 0 / 0	dropped
the same with --target=node	40 / 0 / 12 / 9	0 / 0 / 0 / 0	dropped
nameless sub-package.json, main only	40 / 0 / 5 / 12	0 / 0 / 0 / 0	dropped
named sub-package.json, files in its directory	40 / 0 / 16 / 15	0 / 0 / 0 / 0	dropped
named proxy package.json, files outside its directory	40 / 0 / 8 / 7	40 / 40 / 40 / 40	kept
nameless proxy package.json, files outside its directory	40 / 40 / 40 / 40	40 / 40 / 40 / 40	kept
root sideEffects: false, nameless sub-package.json says true	0 / 0 / 0 / 0	40 / 40 / 40 / 40	kept
root sideEffects: false, { "type": "module" } marker next to the file	0 / 0 / 0 / 0	0 / 0 / 0 / 0	kept

32 of 32 cells are steady (main 24). The two routes agree in 8 of 8 rows (main 4). 7 of 8 rows equal esbuild (main 1).

Behaviour changes

• A path import or a relative import of a file below a nameless package.json takes the sideEffects of that package.json. Before, only an import of its directory did.
• A subpath import into a nested package.json with a name takes the answer of that package.json, not of the package root.
• A proxy package.json ("module": "../esm/a.js") does not decide for a file outside its directory, with or without a name. An unused import Transition from "react-transition-group/Transition" goes from 974,632 B to 54 B (esbuild 77 B).
• A nameless package.json whose sideEffects is true, or another value that is not false or an array, decides for its files (SideEffects::True).
• A module/main pair takes sideEffects, the package and tsconfig.json of the module file (from resolver: take sideEffects and tsconfig.json of a module/main pair from the module file #46765).
• optimizeImports and the React version check read the nearest package.json with a name above the file, for every route.
• src/runtime/bake/package.json loses "sideEffects": false. No build read it, and under the new rule it drops import "./debug". The 6 runtime bundles are byte-identical to main's.

The marker rule is not in this PR

• esbuild and webpack read the nearest package.json, so a { "type": "module" } marker hides the "sideEffects": false of the package root. An earlier build of this branch had that rule.
• Measured on 61 cached packages with a nested package.json: 43 give a larger bundle. One named import grows in 16 of 55 (median +38,144 B). @azure/core-amqp: 15,670 B to 306,861 B (esbuild 331,376 B).
• With the rule of this PR, 0 of 1,030 census builds change size against main.
• The switch is one line in dir_info_uncached. It needs a maintainer decision.

Scope of the fix for #8993

• The issue uses --target bun. The import resolves to the module file, which the package lists in sideEffects. dce/PackageJsonSideEffectsArrayModuleMainBareImport holds that layout, and dce/PackageJsonSideEffectsOfPackageBehindStoreLink holds it behind an isolated-install link.
• With --target=node the import resolves to main, which the package does not list. Bun drops it, as esbuild does.
• The real tfjs packages were not run at this head. resolver: take sideEffects and tsconfig.json of a module/main pair from the module file #46765 measured them: 62,913 B and exit 1 before, 540,049 B and the tensor after.

#18008 and the merge order

• An import through export * of a CommonJS module, in a file that sideEffects: false covers, reads a name off an exports object that the linker drops: ReferenceError: exports_vendor is not defined. On main that needs a package.json with a name. With this PR a nameless one is enough.
• 10 layouts (5 shapes of the import, each below a package.json with and without a name), --target=bun: main prints the expected output in 5 of 10, this PR alone in 0 of 10, this PR merged with bundler: make each read of a run-time export * name depend on the barrel's exports object #46903 in 10 of 10. The merge has no conflict.
• bundler: make each read of a run-time export * name depend on the barrel's exports object #46903 makes each read of a run-time export * name depend on the exports object of the barrel. Its description says why the one-token change at scanImportsAndExports.rs:1290 (the esbuild rule) is not the repair. With that token on this branch, 1,307 of 1,724 fixture builds change.
• dce/PackageJsonSideEffectsFalseExportStarOfCommonJS{Named,Nameless} are todo here. Both pass on the merged tree. The PR that merges second turns them on.

Not fixed here

• A path through a symlink that crosses the deciding package.json (link -> lib/inner, or a link to one file): the answer comes from the path before symlinks are followed, so the two routes give 10 and 10 of 20 (main 9 and 11). A link to a package root, as an isolated install makes, agrees. bundler: read tsconfig.json and "type" for a linked file at its real path #46851 owns the read of type and tsconfig.json at the real path. A sideEffects list must be matched against the spelling that its package.json was read through.
• The packages: "external" return for a tsconfig paths alias skips finalize_result (bundler: keep the cwd tsconfig.json out of the per-file JSX base #38805): 5 and 15 of 20 with a relative import of the same file (main 7 and 13). With that return sent through finalize_result, an alias through a symlink wavers where main is steady, so it stays out.
• The module/main fallback is stored by the import that creates the module. With a require of the same package and two import routes, the bundle still depends on arrival order.
• An import that an onResolve callback declines takes loader.side_effects() (bundle_v2.rs:4135). resolver: mark the Node builtin polyfills as free of side effects #46783 changes that read. Files that a plugin names, in-memory files, and one path with two loaders also keep the first answer (bundler: keep the resolver's JSX and side effects for an import that onResolve declines #43190, bundler: resume the shared resolve pass for imports that went to onResolve plugins #45408).
• After an edit of sideEffects in a package.json during a dev-server session, a file in a subdirectory keeps the old answer until a restart: 0 of 4 routes (main 4 of 4, when a failed import busts the directory cache). type has this behaviour since resolver: read package.json "type" from the nearest package.json, named or not #41232.
• bun add --analyze, bun install --analyze and bun create <component> keep the barrel pass (install --analyze: read the import records before the link #46602). Below a nameless sideEffects: false package.json the scan now does what it does below a named one on main. A package behind an unused re-export is not added: 2 of 4 shapes add it (main 3 of 4). A syntax error or a package that the registry lacks behind an unused re-export no longer stops the scan (main exits 1).
• To turn the barrel pass off for that scan (scan_only = fetcher.is_some() in generate_from_cli) is not the repair. On a build of this branch with that line, below a package.json with a name, bun create ./App.tsx stops at No matching export in "lib/page.html" for import "default" and bun add --analyze exits 1 on a syntax error or a missing package behind an unused re-export. Main reaches the install step of bun create and completes the two --analyze runs. install --analyze: read the import records before the link #46602 measured the same and lists the decision as open.

Overlap with open PRs

• resolver: take sideEffects and tsconfig.json of a module/main pair from the module file #46765: this PR contains its three commits. Its first-path guard, its tsconfig guard and its tests stay. Its nameless-proxy rule is replaced by the per-file read.
• bundler: turn automatic barrel mode off for --ignore-dce-annotations and for the bun test --changed scan #45938: the fourth commit is its diff, byte for byte. Without it, bun test --changed misses the test behind a sideEffects: false barrel below a nameless package.json, which main selects.
• bundler: make each read of a run-time export * name depend on the barrel's exports object #46903, install --analyze: read the import records before the link #46602 and resolver: mark the Node builtin polyfills as free of side effects #46783 merge cleanly. So do typescript: match tsc for experimentalDecorators and emitDecoratorMetadata #46553 and bundler: keep the cwd tsconfig.json out of the per-file JSX base #38805.
• bundler: read tsconfig.json and "type" for a linked file at its real path #46851 rewrites the same loop for type and tsconfig.json: 2 conflict hunks. Do not read the directory of a sideEffects glob or a --filter path as glob syntax #44939 and resolver: match sideEffects entries without "/" in every directory (names in the exact set, globs as **/) #36119 conflict in the sideEffects matching lines and in dce.test.ts. resolver: record enclosing package.json regardless of "name" field #33883 and resolver: don't let the main fallback clobber the module entry's sideEffects #36652 are covered.

Measurements (release builds of main 179664e and of this branch, one build directory, gdb 16.3. perf, valgrind, strace and bloaty are not installed)

• finalize_result instructions per call, main to this PR: entry point 1,018 to 1,007, relative file 1,066 to 1,055, named package 1,158 to 1,091, glob list 1,432 to 1,242, module/main pair warm 2,159 to 1,946, symlinked package 1,171 to 1,105. bun run: the same.
• primary_side_effects calls for 13 resolves: 13 (main 26).
• File-system syscalls of a whole build: equal on 7 fixtures (99 to 150), with and without symlinked packages. bun run: equal.
• size_of::<DirInfo>(): 112 B (main 104 B). size_of::<resolver::Result>(): 296 B on both.
• Release text: 107,559,182 B (main 107,557,134 B), with bundler: turn automatic barrel mode off for --ignore-dce-annotations and for the bun test --changed scan #45938.
• 20,000-module build, 12 interleaved rounds: main 664 ms, this branch 666 ms, noise about 100 ms.
• bun test --changed: 5 of 5 barrel shapes select the affected test (main 4 of 5).
• Sibling fixtures: a barrel with a syntax error in an unused re-export gives one outcome in 24 of 24 builds (main 14 and 10). optimizeImports on a named sub-package: one outcome in 30 of 30 (main 24 and 20).
• A store dependency with TSX under an isolated install builds 10 of 10 on both. type through exports and a file link equals main in 24 of 24 cells.

Tests

• 61 new cases and 2 todo cases turned on (dce/PackageJsonSideEffectsGlobNoMatches, dce/PackageJsonSideEffectsNestedDirectoryRemove). The NamelessProxy*, *ModuleMain* and tsconfig/ModuleMainPair* cases come from resolver: take sideEffects and tsconfig.json of a module/main pair from the module file #46765, and 9 cases come from bundler: turn automatic barrel mode off for --ignore-dce-annotations and for the bun test --changed scan #45938.
• barrel/SideEffectsFalseOfNearestPackageJson{Directory,Path}ImportArrivesFirst put the two routes in two files. The second file is parsed after the imports of the first are resolved, so the order needs no timing. The path-first case fails 20 of 20 on main.

Self-review: 15 concerns raised, 13 addressed. An earlier build read type, tsconfig.json and sideEffects at the real directory and had the marker rule. The review found that the first failed a build that main completes (a store dependency with TSX) and that the second is a separate decision, so both are out. Not addressed: test rows for bun add --analyze, and the stale answer after a directory-cache bust (a follow-up in bust_dir_cache).

Suites run with the debug build: 28 files of test/bundler and test/bundler/esbuild, test/bake, test/js/bun/resolve, test/cli/test/test-changed.test.ts, test/cli/run/run-cjs.test.ts. The only failures are 5 s timeouts of the debug build on this machine, in files this PR does not touch. The release builds pass those cases.

---

no test proof · iteration 0 · platform-specific test(s) that do not run on this machine, deferring to CI, which covers all platforms: test/cli/test/test-changed.test.ts, test/bundler/esbuild/dce.test.ts

[robobun]

^{Updated 11:15 PM PT - Oct 26th, 2026}

✅ @robobun, your commit d8920fdef427278dbf7a66d3d63d8af06876495f passed in Build #133432! 🎉

---

🧪   To try this PR locally:

bunx bun-pr 46911

That installs a local version of the PR into your bun-46911 executable, so you can run:

bun-46911 --bun

[robobun]

Status: open, ready for review. Merge #45938 and #46903 first.

How I reproduced it (main 179664e and release 1.4.3, Linux x64):

1. node_modules/icons/package.json is { "name": "icons", "version": "1.0.0" }. node_modules/icons/outline/package.json is { "sideEffects": false, "main": "./index.js" } with no name. node_modules/icons/outline/index.js is console.log("file").
2. a.js has import "icons/outline". b.js has import "icons/outline/index.js". e.js imports ./a.js and ./b.js.
3. bun build b.js keeps the file in 40 of 40 builds, and bun build a.js drops it in 40 of 40. bun build e.js keeps it in 5 to 12 of 40 builds. esbuild 0.25.1 drops it by every route.
4. Three more shapes give two bundles on main: the same package.json with --target=node, a nested package.json with a name, and a proxy package.json with a name. On this branch 32 of 32 cells of the 8 x 4 matrix are steady.

barrel/SideEffectsFalseOfNearestPackageJsonPathImportArrivesFirst in test/bundler/bundler_barrel.test.ts holds the two-file case with no timing: it fails 20 of 20 on main. The new cases in test/bundler/esbuild/dce.test.ts hold each route alone.

PR: #46911

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• src/resolver/resolver.rs
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Walkthrough

The resolver now tracks the nearest package manifest that declares a name or sideEffects value. Barrel optimization respects ignoreDCEAnnotations, and scan-only builds skip barrel optimization. Changed-file matching checks every matching graph copy. Tests and documentation cover these changes and per-file tsconfig selection.

Changes

Package metadata and bundler resolution

Layer / File(s)	Summary
Resolve package side-effect metadata src/resolver/dir_info.rs, src/resolver/package_json.rs, src/resolver/resolver.rs, src/resolver/result.rs, src/runtime/bake/package.json, test/bundler/esbuild/dce.test.ts	The resolver caches the nearest package manifest that declares a name or sideEffects value. Parsing distinguishes a missing field from explicit true or unsupported values. Tests cover package metadata and import paths.
Barrel optimization conditions src/bundler/barrel_imports.rs, test/bundler/bundler_barrel.test.ts, docs/bundler/index.mdx, docs/snippets/cli/run.mdx, packages/bun-types/bun.d.ts, src/runtime/cli/Arguments.rs	Automatic barrel optimization for sideEffects: false packages is disabled when DCE annotations are ignored. Explicit optimizeImports entries remain eligible. Tests and documentation describe these conditions and package lookup.
Changed-file graph scanning src/bundler/bundle_v2.rs, src/runtime/cli/test/ChangedFilesFilter.rs, test/cli/test/test-changed.test.ts	Scan-only bundles disable barrel optimization. Changed-file matching marks every matching on-disk graph source. Tests cover changed files behind unused re-exports.

Per-file tsconfig selection

Layer / File(s)	Summary
Per-file tsconfig selection tests test/bundler/esbuild/tsconfig.test.ts	Tests cover JSX, decorator, class-field, and decorator-metadata settings selected beside package module and main files. Cases include bundled imports, entry points, unbundled output, require(), and an onResolve callback.

Possibly related PRs

• oven-sh/bun#45938: Both changes address automatic barrel optimization based on sideEffects metadata and scan behavior.
• oven-sh/bun#46783: Both changes affect resolver side-effect metadata consumed by import resolution.
• oven-sh/bun#46765: Both changes address which package metadata applies to selected module and main files.

Suggested reviewers: jarred-sumner

Priority: Normal

Severity of issue fixed: Medium

Merge Risk: Minimal · previous review 45691

No actionable issue was established in the reviewed changes; they are mergeable after normal checks.

Pre-merge checks: 4

Check name	Status	Explanation
Title check		The title clearly describes the primary resolver change: reading sideEffects from the applicable package.json above the resolved file instead of from the import route.
Linked Issues check		[#8993] Resolver::finalize_result now reads primary side-effect data from DirInfo.package_json_for_side_effects, which selects the nearest package.json with name or sideEffects above the res…
Out of Scope Changes check		The changes remain connected to [#8993]. Resolver and package metadata changes implement per-file sideEffects selection. Barrel optimization changes and BundleV2.scan_only preserve correct optimiz…
Description check		The description is complete and relevant. It explains the problem, the fix, behavior changes, known limitations, test coverage, verification results, and performance impact. Although it does not use t…

Full details: Linked Issues check

Explanation

[#8993] Resolver::finalize_result now reads primary side-effect data from DirInfo.package_json_for_side_effects, which selects the nearest package.json with name or sideEffects above the resolved file. This removes the directory-versus-path route difference and covers the module/main package layout. The DCE regression tests include the sideEffects array with module and main cases, and the PR reports the corresponding --target=bun fixture. The real TensorFlow packages were not run at this head, but the focused regression coverage and resolver behavior support the required fix.

Full details: Out of Scope Changes check

Explanation

The changes remain connected to [#8993]. Resolver and package metadata changes implement per-file sideEffects selection. Barrel optimization changes and BundleV2.scan_only preserve correct optimization and graph scanning after that selection changes. ChangedFilesFilter changes make bun test --changed find every graph copy used by the regression tests. CLI help, type declarations, and documentation describe the changed ignoreDCEAnnotations behavior. The runtime package metadata edit prevents the new lookup from dropping its debug import. Supporting tests and the removed resolver helper are in scope.

Full details: Description check

Explanation

The description is complete and relevant. It explains the problem, the fix, behavior changes, known limitations, test coverage, verification results, and performance impact. Although it does not use the exact headings "What does this PR do?" and "How did you verify your code works?", it provides the required information in equivalent sections.

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Review comments at @test/bundler/bundler_barrel.test.ts:
- Around line 167-188: Extract the repeated `/node_modules/autolib/**` entries
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• src/bundler/barrel_imports.rs
• src/bundler/bundle_v2.rs
• src/resolver/dir_info.rs
• src/resolver/package_json.rs
• src/resolver/resolver.rs
• src/resolver/result.rs
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• src/runtime/cli/Arguments.rs
• src/runtime/cli/test/ChangedFilesFilter.rs
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• src/resolver/result.rs
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[claude]

Findings marked 🟡 are optional suggestions and need no follow-up push.

[claude]

🔴 Apps whose root package.json has no name but "sideEffects": false and that export * from a CommonJS package now get a bundle that throws ReferenceError at runtime; main bundled them correctly. package_json_for_side_effects at src/resolver/resolver.rs:6476-6479 lets a nameless package.json decide, so the project's own vendor.ts becomes NoSideEffectsPackageJson and the linker drops its exports object that the import still reads (#18008). Fix: keep #18008 from widening to nameless package.json: either land the linker fix for export-star-of-CommonJS under sideEffects: false in the same PR, or do not let a nameless package.json decide for files the linker cannot yet handle, and un-todo dce/PackageJsonSideEffectsFalseExportStarOfCommonJSNameless. [also at: src/resolver/resolver.rs:1605 - Projects whose root package.json has "sideEffects": false but no name can now get a bundle that throws…; src/resolver/package_json.rs:215 - Projects whose root package.json has "sideEffects": false but no name now crash at runtime with ReferenceError: exports_vendor is not defined where main runs fine.; +1 more]

Why this was flagged

A project has /package.json = { "private": true, "type": "module", "sideEffects": false } (no name), src/vendor.ts = export * from "dep" where dep is CommonJS, and src/entry.ts importing a name from ./vendor. dir_info_uncached (src/resolver/resolver.rs:6476-6479) now picks the nameless package.json because decides_side_effects() (src/resolver/package_json.rs:215) is true for a sideEffects field, and finalize_result (resolver.rs:1600-1603) marks vendor.ts NoSideEffectsPackageJson. The linker then drops vendor.ts's exports object while the importer still reads the name off it, and the output throws ReferenceError: exports_vendor is not defined at runtime. The PR's own test dce/PackageJsonSideEffectsFalseExportStarOfCommonJSNameless (test/bundler/esbuild/dce.test.ts) is marked todo: true for this case; the Downsides section calls it accepted, but it is a working build turning into a runtime crash for a common app layout (private app package.json without a name).

Verification: decides_side_effects() (src/resolver/package_json.rs:214-216) is !self.name.is_empty() || !matches!(self.side_effects, SideEffects::Unspecified), so a nameless package.json with any sideEffects key decides. src/resolver/resolver.rs:1600-1603 applies to every route including the relative ./vendor import, so src/vendor.ts becomes NoSideEffectsPackageJson. The bundle worked on main.

[robobun]

The regression is real when this PR merges alone. The description now gives the merge order: #46903 first. #46903 is the linker change for #18008. It makes each read of a run-time export * name depend on the exports object of the barrel.

10 layouts (5 shapes of the import, each below a package.json with and without a name), --target=bun:

build	layouts that print the expected output
main 179664e	5 of 10 (the 5 below a name throw)
this PR alone	0 of 10
this PR merged with #46903	10 of 10

The merge has no conflict. Both dce/PackageJsonSideEffectsFalseExportStarOfCommonJS* cases pass on the merged tree with todo removed. The PR that merges second turns them on.

Why the two other ways are not in this PR:

• The linker change is not copied here. bundler: make each read of a run-time export * name depend on the barrel's exports object #46903 is a draft that waits on bundler: name the namespace of an external export * in a non-entry module #41220, and a copy brings that open dependency into this PR.
• The rule for a nameless package.json is not narrowed. To ignore a nameless package.json everywhere fails the dce/PackageJsonSideEffectsFalseRemove* cases that pass on main, because their demo-pkg/package.json has no name. To ignore it only outside node_modules makes a directory import of such a package keep code that main drops.

I leave this thread open until #46903 is in.

[claude]

Beyond the inline findings from the earlier review, this pass also checked the SideEffects array parser at src/resolver/package_json.rs:707-790 against the new nameless-package.json rule: a root { "sideEffects": ["*.css"] } with no name now applies to the project's own files, and the parser's existing .css skip means bare CSS imports below it are dropped. That skip predates this PR (it only widens which package.json files it reaches), so it was not raised as a new finding.

Extended reasoning...

The two commits since the prior review (6058ae0, 45691cc) only share a test fixture and shorten comments; the resolver, bundler and ChangedFilesFilter logic is unchanged, so the earlier inline findings still describe the current code. This run found no new bugs and ruled out one candidate, the pre-existing .css drop in the sideEffects array parser, which the nameless-package.json rule now reaches for project-root files.

Still open from earlier reviews (1):

• 🔴 src/resolver/resolver.rs:6478 — Apps whose root package.json has no name but "sideEffects": false and that export * from a CommonJS package now get a b…

If you have decided not to act on one of these findings, resolve its thread (a reply alone leaves it open) and the next review stops counting it. To review this commit again now, use Re-run on its "Claude Code Review" check.

[robobun]

On the .css skip in the sideEffects array parser: a bare CSS import is not dropped. I checked it, because the note in the last review says it is.

entry.js has import "./styles.css" and import "./polyfill.js". The package.json above it has a name or no name, and sideEffects is false, ["*.css"], ["./styles.css"] or ["*.css", "./polyfill.js"]. bun build entry.js --outdir out, release builds of main 179664e and of this branch:

• The CSS is in the output in 16 of 16 cells.
• polyfill.js shows the documented change. Below a package.json with no name, main keeps it in 4 of 4 cells. This branch keeps it in 1 of 4 (the list that names it), which is what both builds do below a package.json with a name.

[robobun]

Merged main (8a0e49e) into this branch.

• One conflict, in src/resolver/result.rs. Main (98a4365, Fix use-after-free of BuildMessage.position.file: real lifetimes for Source, Path, ImportRecord and resolve results #46834) made the impl impl<'r> Result<'r> and edited the doc comment of deref_package_json. This PR deletes deref_package_json. The resolution has the impl<'r> Result<'r> and the path signature of main, without deref_package_json.
• cargo check --workspace passes on the merged tree (Linux x64).
• Tests, on a local debug build that contains this merge and the main merges of six other open PRs: test/bundler/bundler_barrel.test.ts (86 pass), test/bundler/esbuild/dce.test.ts (122 pass, 25 todo), test/bundler/esbuild/tsconfig.test.ts (30 pass, 3 todo), test/cli/test/test-changed.test.ts (24 pass).

[claude]

Still open from earlier reviews (1):

• 🔴 src/resolver/resolver.rs:6476 — Apps whose root package.json has no name but "sideEffects": false and that export * from a CommonJS package now get a b…

If you have decided not to act on one of these findings, resolve its thread (a reply alone leaves it open) and the next review stops counting it. To review this commit again now, use Re-run on its "Claude Code Review" check.