Implement --extend-fixable and --extend-unfixable variants in CLI

[ljnsn]

Consider the following ruff config:

[tool.ruff]
fix = true
unfixable = ["F401", "F841"]

F401 and F841 are added as unfixable so that ruff doesn't automatically remove violating lines on file save (it's set up in the editor for autoformat). I do want to enable them in my pre-commit config though. So what I have done is configure the ruff hook like so:

      - id: ruff
        name: ruff
        entry: ruff
        args: ["--fixable=F401,F841"]
        require_serial: true
        language: system
        types: [python]

However, this makes ruff consider only those two codes as fixable. So I thought I could fix it by passing --unfixable=E501, for example, assuming that would override the value set in the ruff config. The doesn't seem to be the case though, ruff still does not fix the errors.

This does not depend on pre-commit btw, the same can be reproduced by just running ruff from CLI. Essentially, I'm looking for a way to overwrite unfixable, without using --isolated, because there is more config than the minimal example above.

Is there a generally recommended way to do this?

[charliermarsh]

I would've expected --unfixable=E501 to work. As a hacky workaround, could you try --fixable=ALL,F401,F841? If we add --extend-fixable, as requested today (hah) in #4272, then --extend-fixable=F401,F841 would also work.

[ljnsn]

Thanks for the quick answer. It's not a coincidence, #4272 was opened by a colleague of mine, but I didn't know about it until now 😄

Your suggested workaround works, it's even sufficient to pass --fixable=ALL. An extend-fixable would be great though.

[charliermarsh]

Oh, hah, that's funny :)

I'll keep this open to track --extend-fixable, it really should exist to mirror the --extend-select variants.