Description

fix #3474

The _addedImports of the plugin context only exists for each hook in isolation, e.g. load() and transform(). In importAnalysis.ts, we handle _addedImports in the transform() hook, so only addWatchFile in transform() hook works. load() was always being ignored.

This PR saves the _addedImports from load() (cached via ModuleNode weak map), and re-instates in the transform() hook later.

NOTE: this is not supported for CSS, looks like we hardcode dependency handling for our CSS plugin only.

Additional context

https://rollupjs.org/plugin-development/#this-addwatchfile

I also tried supporting this in resolveId() as the Rollup docs mention that it supports it, however I reverted it (see 3rd commit) as it doesn't seem to work in Rollup (vite build --watch). Plus the implementation to support in resolveId() has a few downsides:

• Since resolveId doesn't guarantee a ModuleNode yet, we have to cache by the id string (unable to GC)
• resolveId can be called but we don't necessarily want to load it. Saving the _addedImports could pollute subsequent load + transform

What is the purpose of this pull request?

• Bug fix
• New Feature
• Documentation update
• Other

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• Read the Contributing Guidelines, especially the Pull Request Guidelines.
• Check that there isn't already a PR that solves the problem the same way to avoid creating a duplicate.
• Provide a description in this PR that addresses what the PR is solving, or reference the issue that it solves (e.g. fixes #123).
• Update the corresponding documentation if needed.
• Ideally, include relevant tests that fail without this PR but pass with it.