Fix style compilation failure when importing components via tsconfig path aliases

[ossaidqadri]

Changes

• normalizeFilename in vite-plugin-utils now handles relative paths starting with . (e.g. ./src/components/Foo.astro). On certain environments (Windows + newer Node.js), Vite can produce a relative virtual module ID for style sub-requests when the parent component is imported via a TypeScript path alias. The previous code had no branch for this case, so the relative path was passed unchanged to the compile metadata cache lookup — which was stored with an absolute path — causing a cache miss and a build error.
• The fix resolves relative paths against config.root, consistent with how /@fs and /path variants are already handled.

Testing

• Added a new test fixture (alias-path-alias-style) with a minimal Astro project: a tsconfig.json @/* path alias importing an Astro component that has a scoped <style> tag.
• The build test (test/alias-path-alias-style.test.js) verifies the build succeeds and that the scoped CSS from the aliased component appears in the output — directly covering the regression path.

Docs

• No docs update needed. This is an internal path normalization fix with no user-facing API change.

Fixes #15963

[changeset-bot]

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Latest commit: 3aa463b

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[Copilot]

Pull request overview

This PR fixes an Astro/Vite style virtual-module cache miss when .astro components are imported via TypeScript paths aliases and Vite emits relative IDs (e.g. ./src/...) for style sub-requests, by normalizing those relative filenames to the same absolute form used for compile metadata caching.

Changes:

• Extend normalizeFilename() to resolve .//relative IDs against config.root (via URL + viteID()), preventing compile-metadata cache misses.
• Add a new fixture project (alias-path-alias-style) reproducing the tsconfig paths + scoped <style> regression.
• Add a build test to ensure the aliased component renders and its CSS is present in build output.

Reviewed changes

Copilot reviewed 8 out of 9 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
packages/astro/src/vite-plugin-utils/index.ts	Normalize relative .-prefixed filenames to root-resolved absolute Vite IDs for consistent metadata cache keys.
packages/astro/test/fixtures/alias-path-alias-style/**	New minimal fixture exercising tsconfig paths alias importing an Astro component with component CSS.
packages/astro/test/alias-path-alias-style.test.js	Regression test validating build success and presence of component styles.
.changeset/fix-style-path-alias.md	Patch changeset entry documenting the fix.
pnpm-lock.yaml	Adds the new fixture as a workspace importer dependency on astro.

Files not reviewed (1)

• pnpm-lock.yaml: Language not supported

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[codspeed-hq]

Merging this PR will not alter performance

✅ 18 untouched benchmarks

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_{Comparing ossaidqadri:fix/15963-style-path-alias (3aa463b) with main (2dcd8d5)}

[ossaidqadri]

The Test (integrations): ubuntu-latest (node@22) failure is a pre-existing flake — @astrojs/mdx timed out at 70s. The same matrix job passed on main the same day, and the other integrations matrix jobs (node@24 on ubuntu, windows, and macos) all passed on this PR. My change only touches packages/astro/src/vite-plugin-utils/index.ts and a new test fixture — nothing in packages/integrations/mdx.

[ossaidqadri]

@matthewp

[ossaidqadri]

@matthewp

can you update the status on this