fix(optimizer): externalize virtual modules for html like files

[Copilot]

Fix issue #14151: Call shouldExternalizeDep for virtual modules in dep-scan

fixes #14151
close #14206

• Explore repository structure and understand the issue
• Build the vite package successfully
• Analyze the scan.ts file and identify the fix location
• Implement the fix to call shouldExternalizeDep after build.onResolve({ filter: htmlTypesRE }
• Create a test case in playground/optimize-deps
• Lint and build the changes
• Verify the fix manually by starting dev server
• Test with reproduction from issue [plugin vite:dep-scan] throw an error when start the dev server **at the first time** with import a virtual file #14151
• Run security check (CodeQL) - no vulnerabilities found
• Address review feedback (inline script, remove .gitignore entry)

Problem

When importing a virtual module with an HTML-like file extension (.vue, .svelte, .html, .astro, .imba), the dependency scanner would throw an ENOENT: no such file or directory error during the first dev server start. This happened because the scanner attempted to read virtual modules from the filesystem.

Solution

Added a check using shouldExternalizeDep() in the htmlTypesRE onResolve handler (line 505 in scan.ts). This function checks if a module is virtual (by detecting the null byte prefix \0 or if the resolved ID equals the raw ID) and returns early to externalize it, preventing the scanner from trying to load it from disk.

Changes Made

Core Fix (4 lines):

• Modified packages/vite/src/node/optimizer/scan.ts to call shouldExternalizeDep() before trying to load HTML-like files

Test Case:

• Added virtual module plugin in playground/optimize-deps/vite.config.js providing virtual:test-virtual-file/Foo.vue
• Updated playground/optimize-deps/index.html with inline script to test virtual module import
• Added test cases in playground/optimize-deps/__tests__/optimize-deps.spec.ts to verify no scan errors occur

Verification:

• ✅ Dev server starts without errors
• ✅ Virtual modules with .vue extension load correctly
• ✅ No security vulnerabilities (CodeQL check passed)
• ✅ Lint and format checks passed
• ✅ Reproduced and verified fix with original issue scenario

Original prompt

Call shouldExternalizeDep after build.onResolve({ filter: htmlTypesRE } in @vitejs/vite/files/packages/vite/src/node/optimizer/scan.ts to fix @vitejs/vite/issues/14151 . Add a test in playground/optimize-deps

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[sapphi-red]

@copilot please fix the test failure

[Copilot]

@copilot please fix the test failure

Addressed in commit 1c117e6. Inlined the script and removed the .gitignore entry. The test should now work correctly with the inlined script content in index.html.

[pkg-pr-new]

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commit: acd660e