Support contentRegex for TextMate grammar

[Aerijo]

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Issue or RFC Endorsed by Atom's Maintainers

atom/first-mate#109

Description of the Change

NOTE: Requires update on first-mate dependency to make the contentRegex property be picked up in the first place.

Adds support for the contentRegex property existing on TextMate grammars. Treats it as an Oniguruma regex, so that the TextMate grammar is consistent with itself.

Alternate Designs

Could make the contentRegex a regular JS regex, but then it would be the only regex like that for a TextMate grammar.

Possible Drawbacks

Currently it looks at the whole file, which is potentially dangerous for performace. The use case in the linked issue would be fine with 20 lines or less. Declaring how many lines it wants would require more design choices though.

Verification Process

Manually

Release Notes

• Add support for contentRegex on TextMate grammars

[nathansobo]

I added some basic test coverage for the added logic. Waiting on a green build and then I will merge. Thanks for contributing this!

[nathansobo]

Argh. Got bit by a flaky build failure that I'm actively fighting on another thread. Rebuilding.

[nathansobo]

Re-triggered the build manually and it passed. Not sure why that is not indicated on the PR.

[nathansobo]

Thanks again for your contribution!