test: sync enhanced-resolve#579 tsconfig paths fall-through#212
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stormslowly merged 1 commit intoMay 13, 2026
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When a tsconfig `paths` pattern (e.g. `"@*": ["./src/*"]`) matches a request like `@sentry/react` but the mapped path does not exist on disk, resolution must fall through to normal node_modules lookup. This matches TypeScript's native behavior and was fixed upstream in webpack/enhanced-resolve#579. rspack-resolver already handles this correctly (the architecture in `load_tsconfig_paths` iterates candidates and returns `Ok(None)` on miss, letting the outer pipeline continue with alias and bare module resolution). This commit adds the regression test only — no source changes. Refs: webpack/enhanced-resolve#579 Refs: webpack/webpack#20944
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Pull request overview
This PR syncs a regression test from enhanced-resolve to ensure TypeScript tsconfig.paths behavior matches TypeScript: if a paths mapping matches a specifier but none of the mapped targets exist, resolution should fall through to normal node_modules lookup.
Changes:
- Added a new async test
tsconfig_paths_scoped_pkg_fallthroughcovering@*mapping fall-through for scoped packages. - Introduced a dedicated fixture case (
scoped-pkg-fallthrough) with atsconfig.json, a mapped local module, and a scoped package undernode_modules.
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Show a summary per file
| File | Description |
|---|---|
| src/tests/tsconfig_paths.rs | Adds regression test asserting paths fall-through to node_modules when mapped targets don’t exist. |
| fixtures/tsconfig/cases/scoped-pkg-fallthrough/tsconfig.json | Defines baseUrl + paths mapping ("@*": ["./src/*"]) to reproduce the scenario. |
| fixtures/tsconfig/cases/scoped-pkg-fallthrough/src/helper/index.ts | Provides a resolvable mapped target for @helper. |
| fixtures/tsconfig/cases/scoped-pkg-fallthrough/node_modules/@sentry/react/package.json | Minimal scoped package metadata for node_modules resolution. |
| fixtures/tsconfig/cases/scoped-pkg-fallthrough/node_modules/@sentry/react/index.js | Minimal entry file for the scoped package resolution target. |
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hardfist
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May 13, 2026
stormslowly
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Summary
Sync the regression test from webpack/enhanced-resolve#579 (fixes webpack/webpack#20944).
When a tsconfig
pathspattern matches a request but the mapped target does not exist on disk, resolution should fall through to normalnode_moduleslookup — matching TypeScript's native behavior.Investigation
rspack-resolver is not affected by this bug. The architecture in
load_tsconfig_paths(src/lib.rs) iterates every candidate path and returnsOk(None)if none resolve, letting the outer pipeline continue withload_alias→require_bare→node_modulesresolution.This PR adds the regression test only (no source changes).
Test plan
cargo test --all-features tsconfig_paths_scoped_pkg_fallthroughpasses