feat: add warnings when globals are missing

[MatanBobi]

What: Adds a warning when we weren't able to setup logic through test runner globals (afterEach, beforeAll, afterAll).

Why: This was raised in #1240 and I believe it's worth adding because some stuff won't work for users so they should have a warning stating why.

How:

Adding else blocks in the relevant places.

Checklist:

• [ ] Documentation added to the
  docs site
• Tests
• TypeScript definitions updated
• Ready to be merged
  

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[codecov]

Codecov Report

Merging #1244 (39fdc6c) into main (c04b8f0) will not change coverage.
The diff coverage is n/a.

@@ Coverage Diff @@## main #1244 +/- ## ========================================= Coverage 100.00% 100.00% ========================================= Files 4 4 Lines 192 192 Branches 38 40 +2 ========================================= Hits 192 192 

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[timdeschryver]

I like the idea!
I'm probably "stealing" this for Angular Testing Library :)

[ITenthusiasm]

@MatanBobi (and @timdeschryver, if you're still interested in Angular's implementation), it seems like this change could potentially run the risk of cluttering the logs for developers who intentionally aren't using the automatic cleanup functions. (For example, I'm using vitest, which by default doesn't have globals enabled. But I'm sticking with Vitest's defaults intentionally.) Particularly, this warning will be logged for every single test file that tests React components.

Is it possible to only display this warning once per call to jest/vitest/etc.? For instance, is there a way that an ENV var (e.g., *TL_GLOBAL_WARNING_LOGGED) could be set (which only lasts the lifetime of npx jest, npx vitest, etc.)? Or maybe something else would be possible?

[timdeschryver]

Thanks @ITenthusiasm that's a valid point, we'll look into this.