feat: enable usage of function as library fileName, close #3585

[gobeli]

Description

This PR would enable users of the library mode to use a function to define the output filename. (As discussed in #3585)

I didn't see existing tests in this area, but maybe I missed it, glad to add some if required.

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What is the purpose of this pull request?

• Bug fix
• New Feature
• Documentation update
• Other

Before submitting the PR, please make sure you do the following

• Read the Contributing Guidelines.
• Read the Pull Request Guidelines and follow the Commit Convention.
• 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).
• Ideally, include relevant tests that fail without this PR but pass with it.

[gobeli]

Changed the existing lib tests within the playground package

[Shinigami92]

Changed the existing lib tests within the playground package

I just wonder: don't we have a test only for fileName: string?
May I ask you to cover all three possibilities. 🙂
This would prevent regression in the future and stabilize this feature 🙂

[gobeli]

I just wonder: don't we have a test only for fileName: string?
May I ask you to cover all three possibilities.
This would prevent regression in the future and stabilize this feature

Yeah would be a good idea, I didn't get it to work without creating multiple playgrounds though 🤔
Would that be a problem? Or do you have any pointers on how to do it without creating more playgrounds?

[Shinigami92]

Maybe you can extract the logic and create a unit-test for it 🤔
You can orient yourself on the __tests__ folder in packages/vite/src/node/__tests__ and create one for client
Then the playground test is enough for the integration test and then the unit test covers the rest 🙂

[gobeli]

Ok, I gave it a shot with the unit tests

[Shinigami92]

I think we need a "exclude": ["**/__tests__"] in .../client/tsconfig.json like in .../node/tsconfig.json

Also I don't see the running test in the checks 🤔
I see some for src/node

These unit tests are only in test-serve. @patak-js Do you know a bit more about this and how we configure them for src/client?

Nevermind 🤦 I mixed some PRs, sorry

Test run successfully here: https://github.com/vitejs/vite/pull/3625/checks?check_run_id=2727359038#step:10:32

[Shinigami92]

Okay, seems we need a non-null assertion at the calling location

[gobeli]

Yeah, it should be fixed now

Resolved