test(glob-import): cover absolute base resolving to files outside root

[shulaoda]

Summary

Adds an e2e regression test for import.meta.glob with base: '/' when the glob pattern matches files outside of Vite's project root.

In this scenario the generated import path must be root-relative (/<relative-to-root>), not importer-relative — otherwise the bundler resolves it against the importer and lands on a non-existent file.

Mirrors the minimal reproduction from rolldown/rolldown#9144 (fixed by rolldown/rolldown#9145), where the rolldown-native viteImportGlobPlugin was emitting an importer-relative path for files outside root.

Context

At build time, Vite's importGlobPlugin delegates to the rolldown-native plugin when config.isBundled is true (see packages/vite/src/node/plugins/importMetaGlob.ts:46), and isBundled is set whenever isBuild is true (packages/vite/src/node/config.ts:936).

So the new test case exercises the exact code path that caused the bug in the reproduction repo whenever VITE_TEST_BUILD=1 is set.

Implementation

After #22466 moved all fixtures of playground/glob-import/ into a root/ subdirectory, the playground naturally has space outside Vite's root: any sibling of root/ inside the copied playground tree is outside Vite's root but still inside the e2e temp dir. This matches the shape of the original reproduction repo (app/ + sibling external/).

The new test reuses that structure — no new playground, vite config, or npm script is required:

playground/glob-import/
├── __tests__/
│   └── glob-import.spec.ts   # adds `absolute base with files outside of root`
├── external/                 # outside Vite root, but inside the copied playground
│   ├── x.js
│   └── y.js
└── root/                     # vite root (auto-detected by the test harness)
    └── index.html            # appends an `<h2>Absolute base outside root</h2>` section
                              # with `import.meta.glob('../external/*.js', { base: '/', eager: true })`

[sapphi-red]

How does it look like if we add root subdirectory to glob-import playground?

[shulaoda]

How does it look like if we add root subdirectory to glob-import playground?

done

[sapphi-red]

I was thinking of changing the structure to put everything in root.

[shulaoda]

I was thinking of changing the structure to put everything in root.

This approach could work, but it’s relatively complex and has a broad impact. I think it might be better to make this change after this PR.

[sapphi-red]

Can we first move everything in root in a separate PR and then rebase this one on top of that?