Fix haste module resolution inside of scoped modules (Fixes #241)

[empyrical]

Summary

This (WIP!) pull request attempts to fix issues with Haste and scoped modules.

It is a WIP, because I was able to figure out how to get it working on Posix - but I still need to work out what the issue is on Win32.

Test plan

Test cases for posix and win32 have been added to traverseDependencies-integration-test.js.

[empyrical]

Figured out the win32 problem. This requires a fix to jest-haste-map, and have made a pull request:

jestjs/jest#6980

Once it is merged and a version of jest-haste-map with it is released, this PR can be updated with it and the win32 issue will be resolved.

[rafeca]

nit: can you remove the console.error()?

[empyrical]

Oops, forgot that debug line there! Fixed it up.

[rafeca]

Wow thanks a lot for the PR 😍

Codewise LGTM, can you run prettier to get the linter happy? (I guess that the failing tests will get fixed with the new version of jest-haste-map.

[empyrical]

Prettified, and cleaned up the debug line

[empyrical]

So because jest-haste-map had a breaking change in it recently, it is warned that my change might not land in a release for some time.

There is a way to go for fixing windows support in the meantime, but I'd like your input @rafeca before I push it to this PR.

If I include the patched version of getWhiteList with Metro, and manually swap out the private _whitelist property with a patched version, the Win32 test will pass.

Example:

  static _createHaste(opts: Options): JestHasteMap {
    const hasteMap = new JestHasteMap({
      // ... trimed ...
    });
    hasteMap._whiteList = getWhiteList(opts.providesModuleNodeModules);
    return hasteMap;
  }

An issue would then have to be created to remind to remove this patch when jest-haste-map is updated.

[rafeca]

There is a way to go for fixing windows support in the meantime, but I'd like your input @rafeca before I push it to this PR.

I'd prefer to avoid patching jest-haste-map... can we instead disable the test in win32 until we get a new version of jest-haste-map published? (I'll add this as a known issue in the release notes).

I think I can convince @mjesun to publish a new version of jest-haste-map 😆

[empyrical]

Skipped the test for now, and CI looks good now! 👌

[rafeca]

Yay!! Thanks a lot for this PR 🎉

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