Turbopack: refactor export analysis#92781
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This was referenced Apr 14, 2026
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The refactor moved import handling to a prepass but dropped the case where
an import has no specifiers but has an internal turbopack part ID (e.g.
`import "__TURBOPACK_PART__" with { ... }`). Without this, the tree-shaken
facade loses its dependency on the ModuleEvaluation part, causing side
effects to not execute.
Co-Authored-By: Claude <noreply@anthropic.com>
Two fixes in imports.rs:
1. Re-exports (export { x } from '...') should always have mutable=false
since liveness is determined by the referenced module's own export
description, not the re-exporting module. The refactor incorrectly
propagated is_fake_esm to the mutable flag for re-exports, causing
setter functions to be emitted where getters are sufficient.
2. The snapshot source-map offsets shifted by 4 lines due to the above
change; regenerate the 5 affected basic-tree-shake snapshots.
Co-Authored-By: Claude <noreply@anthropic.com>
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This was referenced Apr 15, 2026
Comment on lines
734
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| let issue_source = self | ||
| .source | ||
| .map(|s| IssueSource::from_swc_offsets(s, span.lo.to_u32(), span.hi.to_u32())); |
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nit: would it make sense to defer constructing this (capture the span instead) the span is 8 bytes but an issueSource is more like 40 and all these ImportMapReferences are for the same source file
| DefaultDecl::TsInterfaceDecl(_) => { | ||
| // not matching, might happen due to eventual consistency | ||
| ( | ||
| magic_identifier::mangle("default export").into(), |
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nit: we reference this in many places, should we have a shared constant? i think it could be rcstr!(mangle("default export") also if we mark mangle as a const fn
lukesandberg
approved these changes
Apr 15, 2026
This was referenced Apr 23, 2026
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Remove
ModuleReferencesVisitorand move everything into theImportMapAnalyzer