Allow ruff to be used as a formatter

[DarkaMaul]

Until astral-sh/ruff#659 is implemented, it could still be helpful to use ruff to format the signatures.

Feel free to close the PR if you believe the perf impact is too big when spanning multiple subprocesses.

[pawamoy]

Thanks! I tried it in a project that renders quite a lot of docstrings, and I don't see any flagrant perf hit.

[pawamoy]

Thanks! I tried it in a project that renders quite a lot of docstrings, and I don't see any flagrant perf hit.

Something might be missing though: the signatures aren't actually formatted 😅 Does it work on your side?

[pawamoy]

Once I add and use the _find_ruff util, I then get this process error:

CalledProcessError(2, ['/media/data/dev/griffe/.venv/bin/ruff', 'format', '--config "line-length=60"', '--stdin-filename', 'file.py', '-'])

Its stderr is:

'error: unexpected argument '--config "line-length' found\n\n tip: a similar argument exists: '--config'\n\nUsage: ruff format --config <CONFIG_OPTION> [FILES]...\n\nFor more information, try '--help'.\n'

I guess we simply have to split that.

[pawamoy]

OK working with the suggestion above. Let me re-check the perfs. UPDATE: same, no perf hit.

[DarkaMaul]

Before merging the PR (if that goes through), the documentation needs to be updated (and some of the docstrings) to reflect that now it can also use ruff when black is not found.