Coala is basically dead -> no major commit in over 2 years. It's getting outdated python-wise (in fact, I had to uninstall some bears to run on CI). It's never been _that_ functional either way.
This diff proposes to replace it with just the regular old arclint. The main reason to not use arclint originally was that:
- you need to have the linter installed to work with arcanist
- arching doesn't have eslint
This introduces a PHP extension (pyrolint) to deal with these problems.
Cons:
- We need to maintain a few PHP files if arcanist changes format - I think linters are relatively safe, they're not big files or complex files anyways.
Pros:
- Lints only the lines we've changed
- Supports ESLint 7 & the brace-rule plugin we use
- Allows to run cppcheck & ESLint as 'optional', so if you haven't got them installed locally it's OK
- Easy to extend with more stuff