[jest-resolve] Add async resolver support

[IanVS]

Summary

This is a stab at #9505. I would love to use jest in vite, and it sounds like this is the next step towards getting there.

I added async methods in the Resolver class and named them ending with Async, but I'm not sure if that's the kind of convention you want. It just helped me to keep everything straight, but I'm happy to rename them. Also, I wasn't super-consistent about putting async at the front or back of names, except that nouns I tried to put it at the front and verbs (methods) at the end. Because an option named resolverAsync sounded worse than asyncResolver. ¯\(ツ)/¯. Again, happy to adjust. Oh, and I didn't rename any of the existing methods, to keep backwards compat.

Fixes #9505

Test plan

I have copied the tests from the sync resolver, and adjusted them to work for the new async version. I didn't add any new test cases, though, but I'm happy to do so if there are holes.

[codecov-commenter]

Codecov Report

Merging #11540 (e58d96b) into main (d7f0975) will decrease coverage by 0.13%.
The diff coverage is 51.86%.

@@            Coverage Diff             @@
##             main   #11540      +/-   ##
==========================================
- Coverage   68.93%   68.79%   -0.14%     
==========================================
  Files         312      312              
  Lines       16412    16580     +168     
  Branches     4760     4817      +57     
==========================================
+ Hits        11314    11407      +93     
- Misses       5071     5146      +75     
  Partials       27       27              

Impacted Files	Coverage Δ
packages/jest-resolve/src/resolver.ts	52.17% <45.61%> (-3.70%)	⬇️
packages/jest-resolve/src/defaultResolver.ts	87.64% <87.50%> (-1.04%)	⬇️
packages/expect/src/utils.ts	96.13% <0.00%> (+0.55%)	⬆️

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[IanVS]

@SimenB, do you have any chance to look over this? I know it's a large PR, and I'd be happy to simplify it if you can think of any ways to do so.

[geekox86]

Greetings. Guys what is the status on this important PR?

[SimenB]

Hello! Thank you so much for tackling this issue!

Back from vacation now. I'll try to give this a look over the weekend (or next week), but no promises 🙂

[SimenB]

(quick look)

[IanVS]

Thanks for the comments, @SimenB. I hope you enjoyed your vacation! I'll do my best to make changes this week or next weekend. I was without power for a few days last week after a big storm, so I'm still catching up on lost time.

[IanVS]

I've rebased on latest master, and recombined the classes together. I apologize if there's too much churn in the diff, I still had to keep some methods broken up, and I arranged them in a way that made sense to me and helped me keep track of everything, but moving things around may have caused some churn.

[IanVS]

@SimenB, is this looking closer to what you want? If so, I will try to keep it rebased on master.

[SimenB]

Hopefully you haven't started to resolve the conflicts as #12373 is about to basically rewrite the default resolver 🙈

This is due to a bug, so hopefully there are no more bug reports before we get to this PR!

[IanVS]

I haven't started yet, though was planning to this weekend. Procrastination pays off yet again!

Thanks for the heads up.

[IanVS]

I took a shot at this and I'll be honest, I'm not sure I am the best one to finish this up. It's been so long since I did this work, I've forgotten what I did, and the new code looks pretty different than before. I've also moved on from trying to use Jest in my own project, so unfortunately I have no personal stake in this work either. I'd be perfectly happy if someone else wants to take this across the finish line, or maybe it just needs to be re-started from scratch, I'm not sure. But I can't really spend any more time on it now, sorry.

[SimenB]

That's perfectly fine @IanVS, thanks! I'll give this a rebase 🙂

[SimenB]

Ok, conflicts resolved. I skipped adding support for exports in async default resolver as I think I'll just remove async support for it (i.e. just delegate to sync). This is the same we did for transformation - while the runtime supports async transform, we don't actually use it ourselves as sync can always be wrapped in a promise

[SimenB]

the code turned out quite dirty, this really needs a good refactor at some point (both runtime and resolver).

However, tests are happy, so let's try with this and hope people test it and report any bugs 🙂

Thank you so much for your patience @IanVS!

[github-actions]

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