Fix roots on Windows

[KuroyukihimeSenpaiSamaChan]

I noticed that on Windows, if you had one bad route in your jest.config.js, it would return 0 route found.
It looked like a bug to me, because this was not what happened on Linux, and there were no error message directly saying a root was wrong.
This simple fix ensure that all roots are checked and registered in the result array before returning anything to callback. What was happening is that the calls being asynchronous and the error check being at the beginning, when it encountered a bad root, it would return the callback and ignore the other roots, which could be ok.

Summary

Test plan

[codecov-io]

Codecov Report

Merging #9549 into master will decrease coverage by 0.02%.
The diff coverage is 50%.

@@            Coverage Diff             @@
##           master    #9549      +/-   ##
==========================================
- Coverage   65.05%   65.03%   -0.03%     
==========================================
  Files         286      286              
  Lines       12123    12124       +1     
  Branches     3004     3005       +1     
==========================================
- Hits         7887     7885       -2     
- Misses       3599     3600       +1     
- Partials      637      639       +2

Impacted Files	Coverage Δ
packages/jest-haste-map/src/crawlers/node.ts	84.52% <50%> (-1.02%)	⬇️
packages/expect/src/utils.ts	94.96% <0%> (-1.26%)	⬇️

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[SimenB]

Seems odd to me that we just ignore errors... This fix seems correct though.

@cpojer thoughts?

[cpojer]

I think this could benefit from tests.

[KuroyukihimeSenpaiSamaChan]

To reproduce the case:

• In a node project, install jest
• Add the jest.config.js with correct roots and one root pointing to a non-existing folder
• Run jest
  • Windows : Says 0 roots found
  • Linux : Find only the existing roots

[KuroyukihimeSenpaiSamaChan]

Actually, I'm sorry. If you want tests, I don't know how to do them for this type of code, I can only tell you of to reproduce the error, like I did earlier.

[SimenB]

Looked into this, and if you provide a non-existent root the behaviour varies quite a bit. With watchman we error with jest-haste-map: Watchman crawl failed. Retrying once with node crawler. and then the node crawler silently ignores the missing directory. However, if we're running on windows it reports 0 regardless of whether there are tests in other directories. This is due to this logic: https://github.com/facebook/jest/blob/00e9e0972bf959e041b1dd249d907402a58c23b5/packages/jest-haste-map/src/crawlers/node.ts#L196-L200

I think all of these behaviors except for watchman's are bugs (and since it fallbacks to a bug, even that behaviour is wrong). IMO the correct solution is to validate that all directories provided as roots exist when we do config normalization, meaning we'd error out way earlier than when we crawl.

I also think we should error in jest-haste-map, but I'm not sure if Metro won't barf if we start doing that?

[github-actions]

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