Why the change from black to ruff?

[peterhinch]

Is there an issue with black or is it simply to perform linting in addition to formatting?

[jimmo]

No issue with black specifically. Like you say, seeing as we already had ruff linting, we now have one tool to do both (i.e. one fewer dependency). It's also quite a lot faster (which is minor but noticeable when you're doing whole-repo checking).

[andrewleech]

ruff format is generally compatible with black, but with a couple of documented differences which I feel ruff does better: https://github.com/astral-sh/ruff/blob/main/docs/formatter.md#intentional-deviations

https://astral.sh/blog/the-ruff-formatter

[sosi-deadeye]

The speed of ruff is ridiculous.

[andrewleech]

I was just wondering how much faster black would be if they ran it through something like cpython... Turns out they already do! (mypyc)
https://ichard26.github.io/blog/2022/05/compiling-black-with-mypyc-part-1/

TLDR it only yielded a 2x speed improvement over pure python.

[peterhinch]

Thanks all for clarifying.