Improve dependency extractor

[rubennorte]

Summary

This refactors the default dependency extractor to make regular expressions less error-prone (building them with a custom DSL) and fixes some bugs:

1. require("foo",) (notice the trailing comma), which is completely valid, wasn't detected.
2. import typeof {foo} from 'foo' was detected as a dependency, when it should've been ignored like import type {foo} from 'foo';.

It also uses negative lookbehind when it's supported.

Performance-wise, it's faster than the previous version as it removes unnecessary capture groups (tested internally at Facebook).

Test plan

Updated unit tests.

[SimenB]

Tests seems to be failing on Node 6?

[rubennorte]

Tests seems to be failing on Node 6?

There's a case that was failing before:

foo.require.requireActual('foo');

I used a negative lookbehind to fix it, but they're only supported in Node 9+. I disabled the test cases that don't work with Node 6 to make CI pass. Once we drop support for Node <10 we can re-enable them.

[SimenB]

Once we drop support for Node <10 we can re-enable them.

Heh, so in like 3 years :P (EDIT: node 8 is EOL Dec 2019, so 3 was a bit of an exaggeration)

Would it be possible to detect support and activate if it's available? Or would that give us different behaviors on different nodes which might be confusing to the user?

[rubennorte]

@SimenB what I disabled was the test, not the support for the feature. I still use feature detection and enable it if it's available.

[SimenB]

Ah, cool! Could we conditionally disable the test/assertions as well, then? To make sure we don't break it 🙂

[codecov-io]

Codecov Report

Merging #7385 into master will increase coverage by 0.05%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #7385      +/-   ##
==========================================
+ Coverage   66.72%   66.78%   +0.05%     
==========================================
  Files         241      242       +1     
  Lines        9356     9372      +16     
  Branches        6        6              
==========================================
+ Hits         6243     6259      +16     
  Misses       3110     3110              
  Partials        3        3

Impacted Files	Coverage Δ
...ckages/jest-haste-map/src/lib/isRegExpSupported.js	100% <100%> (ø)
...ages/jest-haste-map/src/lib/dependencyExtractor.js	100% <100%> (ø)	⬆️

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[github-actions]

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