Add pre-commit configuration

[joshmoore]

Sorry I missed the linting in the dev guide. I can recommend https://pre-commit.com/ for these type of checks, we use it heavily over at tskit: https://github.com/tskit-dev/tskit/blob/main/.pre-commit-config.yaml

Originally posted by @benjeffery in #974 (comment)

[parthxtripathi]

Hey @joshmoore , can i work on this? Could you please let me know what all pre-commit checks are required in zarr?

[joshmoore]

Hi @parthxtripathi.

can i work on this?

That'd be great. Sure.

Could you please let me know what all pre-commit checks are required in zarr?

I imagine we will need to go through this iteratively and find the checks which can be added without too many changes, and then separate out those checks which require more work.

My starting point is usually:

https://github.com/ome/ome-zarr-py/blob/master/.pre-commit-config.yaml

but welcome to hear/see suggestions from others.

[parthxtripathi]

Thank you for the details @joshmoore ! Just to confirm, this issue requires adding the pre-commit configuration to zarr-python right? As a first step, should I add the configuration available in ome-zarr-py to my fork and create a PR? Then I can iteratively work on the configuration!

[benjeffery]

Having been through this process over at tskit I can recommend adding a minimal pre-commit configuration in a PR, then adding additional rules one-by-one in separate PRs. This makes it clear what changes to the code/formatting are from which rules and allows discussion of each one. Some (e.g. black, bugbear etc) can cause a lot of changes, depending on the existing state of the code.

You'll also need some hand-holding in the dev docs, here's ours: https://tskit.dev/tskit/docs/stable/development.html#pre-commit-checks

[joshmoore]

I can recommend adding a minimal pre-commit configuration in a PR, then adding additional rules one-by-one in separate PRs

Thanks, @benjeffery. @parthxtripathi, following that logic, I could see this as an ordering of the hooks:

Should require minimal changes (if any)

• https://github.com/PyCQA/flake8

Hopefully only a few changes

• https://github.com/pre-commit/mirrors-mypy
• https://github.com/adrienverge/yamllint.git
• https://github.com/asottile/pyupgrade

Moderate changes

• https://github.com/pre-commit/pre-commit-hooks
• https://github.com/asottile/seed-isort-config
• https://github.com/PyCQA/isort

Requires lots of changes

• https://github.com/psf/black

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Anyone else have hooks they would like to suggest?

[joshmoore]

I think we've likely got the gist of this. Closing for now (but definitely looking to the day when black will be a part of pre-commit 😄)