I would reckon cleaning up your branch before opening a pull request is good practice. I also rebase a lot, aswell as git reset, and I use wip commits.

Slow hooks are also not a problem in projects I manage as I don't use them.

> Then why would it save time and money if they only get run at the pipeline stage? That would only save substantial time if the pipepline is architected in a suboptimal way: Those checks should get run immediately on push, and first in the pipeline so the make the pipeline fail fast if they don't pass. Instant Slack notification on fail.

That's still multiple minutes compared to an error thrown on push - i.e. long enough for the dev in question to create a PR, start another task, and then leave the PR open with CI failures for days afterwards.

> But the fastest feedback is obviously in the editor, where such checks like linting / auto-formatting belong, IMHO.

There are substantial chunk of fast checks that can't be configured in <arbitrary editor> or that require a disproportionate time investment. (e.g. you could write and maintain a Visual Studio extension vs just adding a line to grep for pre-commit)

The pre-commit tool (which prek is based on) has a large ecosystem of off the shelf checks for various language linters and other checks and a convenient way of writing them (including working out which files have changed and which checks to run based off of that)

The benefit to many of having them as a hook is that you discover it's broken before you pushed your changes, and not when you finally get around to checking the CI on your branch and realising it failed after 30s.

There is of course no reason why you have to have it installed as a precommit hook - many people prefer to run it manually, and the pre-commit tool/prek allows for that.

If you had a shell script hook, yes you would also run that in CI.

Are you asking what advantage pre-commit has over a shell script?

Mostly just functionality: running multiple hooks, running them in parallel, deciding which hooks to run based on the commit files, "decoding" the commit to a list of files, offering a bunch canned hooks, offering the ability to write and install non-shell hooks in a standard way.

The point is enforcement. If there's a newcomer to developing your repo, you can ask them to install the hooks and from thereon everything they commit will be compatible with the processes in your CI. You don't need to manually run the scripts they'll run automatically as part of the commit or push or whatever process

pre-commit provides a convenient way to organize running a collection of shell scripts.

Yes, you can run the CI script locally so you detect errors faster.