fix: don't run import analysis on build in lib

[modderme123]

Description

When running in library mode, import analysis returns strings that aren't analyzable by future bundlers, which prevents assets from being loaded and throws errors in final bundles. The solution is to not run this process at all, and instead require users of a library to import the css directly (which is what must be done currently, this just gets rid of the errors)

Additional context

Fixes #3662

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What is the purpose of this pull request?

• Bug fix
• New Feature
• Documentation update
• Other

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[patak-dev]

Doesn't this break glob imports in lib mode?

DIsmiss

[antfu]

Yeah, good point, sorry I missed that.

@modderme123 Can you share a minimal repro of the problem you are trying to resolve?

[modderme123]

https://github.com/modderme123/vitebug/tree/import-analysis

I'm sure this isn't the tiniest way of triggering import analysis, but it is reasonably small and all sorts of things go wrong when lib mode has the preload import added. A tinier change might be to only disable this if statement: https://github.com/vitejs/vite/blob/main/packages/vite/src/node/plugins/importAnalysisBuild.ts#L155

[patak-dev]

@modderme123 I converted this to a draft, please marked as ready for review later. Thanks!

[modderme123]

To clarify: I should update with the if statement suggested in my comment above and then mark this as ready for review?

[modderme123]

Fixed by #4097