Use pre-commit-uv in CI

[akx]

Summary

Follows up on #17052 to add in pre-commit-uv, which patches pre-commit to use uv for venv creation as well.

More dogfooding! More speed! 😄

Note

I suspect caching could be removed from the pre-commit CI step with this...

Test Plan

How was it tested?

We're about to find out...

[github-actions]

ruff-ecosystem results

Linter (stable)

✅ ecosystem check detected no linter changes.

Linter (preview)

✅ ecosystem check detected no linter changes.

Formatter (stable)

✅ ecosystem check detected no format changes.

Formatter (preview)

✅ ecosystem check detected no format changes.

[AlexWaygood]

How much do you think this is likely to buy us? Testing locally, it still seems to take pre-commit a while to setup the many virtual environments it needs if the pre-commit cache is cold, even with pre-commit-uv. But if the pre-commit cache is hot (which it usually is in our CI), that doesn't cost us anything at all.

I'm also not sure I love the monkeypatching approach pre-commit-uv takes. I appreciate that there's not really any other way to get pre-commit to use uv internally, but it seems kinda fragile. If it bought us a lot, that would be one thing... but it seems like it might not?

[akx]

Testing locally, it still seems to take pre-commit a while to setup the many virtual environments it needs if the pre-commit cache is cold, even with pre-commit-uv.

I've locally installed my global pre-commit with uv tool install pre-commit --with pre-commit-uv==4.1.4, which has made venv creation appreciably faster, and me happier.

But if the pre-commit cache is hot (which it usually is in our CI), that doesn't cost us anything at all.

Looks like it, yeah. The pre-commit lint in this branch is approximately the same speed as in main right now.

I'm also not sure I love the monkeypatching approach pre-commit-uv takes. I appreciate that there's not really any other way to get pre-commit to use uv internally,

I did try for more first-class support once upon a time... pre-commit/pre-commit#3131

but it seems kinda fragile. If it bought us a lot, that would be one thing... but it seems like it might not?

Yeah, I guess it's not worth it here – feel free to close if you like.

FWIW, I wrote a simple action (https://github.com/akx/pre-commit-uv-action/) to do this that I use for some of my projects :)

---

Now that I am investigating pre-commit, though, running the same incantation as in the CI step locally (MacBook Pro, no slouch), with --verbose, shows it's absolutely dominated by actionlint:

$ time pre-commit run --all-files --show-diff-on-failure --color=always --hook-stage=manual --verbose
Validate pyproject.toml..................................................Passed
- duration: 0.14s
mdformat.................................................................Passed
- duration: 1.32s
markdownlint-fix.........................................................Passed
- duration: 1.05s
blacken-docs.............................................................Passed
- duration: 0.31s
typos....................................................................Passed
- duration: 1.24s
cargo fmt................................................................Passed
- duration: 2.01s
ruff-format..............................................................Passed
- duration: 0.05s
ruff.....................................................................Passed
- duration: 0.02s
prettier.................................................................Passed
- duration: 0.18s
zizmor...................................................................Passed
- duration: 0.05s
Validate GitHub Workflows................................................Passed
- duration: 0.32s
Lint GitHub Actions workflow files.......................................Passed
- duration: 26.87s
________________________________________________________
Executed in   34.97 secs    fish           external
   usr time  306.37 secs    0.06 millis  306.37 secs
   sys time   14.57 secs    2.69 millis   14.57 secs

Looking at htop during that workflow linting, it seems the action spawns an unlimited number of shellchecks that compete for a finite number of CPUs' attention... 😩

It could be worth it to limit actionlint to only run in CI if actions are actually changed?

EDIT: Oh... I guess it's the WASI-compiled shellcheck that's slow and heavy, but even more so on a GitHub Actions machine that's starved for cores.

EDIT 2: See #17108 🔧

[AlexWaygood]

I did try for more first-class support once upon a time... pre-commit/pre-commit#3131

yup, I'm aware of the history 😄 thanks for your efforts there!

I've locally installed my global pre-commit with uv tool install pre-commit --with pre-commit-uv==4.1.4, which has made venv creation appreciably faster, and me happier.

Nice. ISTM that it probably has much more of an impact locally than in CI, though. So I'm inclined not to go with this. But thanks anyway!!