workflows: add actionlint workflow

[carlocab]

• Have you followed the guidelines in our Contributing document?
• Have you checked to ensure there aren't other open Pull Requests for the same change?
• Have you added an explanation of what your changes do and why you'd like us to include them?
• Have you written new tests for your changes? Here's an example.
• Have you successfully run brew style with your changes locally?
• Have you successfully run brew typecheck with your changes locally?
• Have you successfully run brew tests with your changes locally?

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This will help us avoid future actionlint errors in our workflows.

• workflows: add actionlint workflow
• Add actionlint error for testing WIP

[Bo98]

I assume it just doesn't complain about the others?

[carlocab]

Yea, it doesn't know what to do with a dynamically generated runner label so just ignores it.

[Bo98]

Annotations should work fine (see: test-bot in Homebrew/core). Are you referring to add-matcher or the process the matcher later does?

[carlocab]

Are you referring to add-matcher or the process the matcher later does?

Both. Annotations work for us otherwise because we use GitHub::Actions::Annotation, which handles emitting the correct relative paths:

brew/Library/Homebrew/utils/github/actions.rb

Line 72 in 92d68e3

@file = self.class.path_relative_to_workspace(file)

I couldn't get this to show annotations without moving everything into GITHUB_WORKSPACE at Homebrew/homebrew-core#128075. I didn't bother trying here, though.

[Bo98]

Ok looks like this actions/runner#765.

[Bo98]

The default is bash -e {0}. Are we avoiding another bash somewhere?

[carlocab]

IIUC correctly in containers the default is sh. Or an sh masquerading as bash.

[Bo98]

Docs appear to suggest sh is only used when bash is not found: https://docs.github.com/en/actions/using-workflows/workflow-syntax-for-github-actions#jobsjob_idstepsshell

[carlocab]

Hmm, weird. I know I've had trouble with [[, ]] in Homebrew/core workflows when I don't set shell: /bin/bash.

[carlocab]

Now getting

shellcheck reported issue in this script: SC2115:warning:4:27: Use "${var:?}" to ensure this never expands to /* 

After dropping this.

[Bo98]

It says it's running:

shell: /usr/bin/bash -e {0}

Is /usr/bin/bash different? Don't think it should be with 22.04.

Though with that said, throwing that error feels like correct behaviour?

[carlocab]

Though with that said, throwing that error feels like correct behaviour?

Yes, agreed. Fixed.

[Bo98]

It's possible it might just not run shellcheck with custom shells, which could make sense.

[carlocab]

I get

/__w/_temp/b13f8fe9-518c-4fd3-af62-a31519cf8e56.sh: 5: shopt: not found

when running without setting the shell to /bin/bash in Homebrew/core. Must have something to do with running in a container, since the shell there is reported as sh -e {0}.

https://github.com/Homebrew/homebrew-core/actions/runs/4678530113/jobs/8287369304?pr=128075#step:5:34

[Bo98]

Ah yes, that'll be because the shell is evaluated before the container is started, so it won't know whether bash is available.

Unless we need/want to avoid --noprofile --norc -o pipefail, we could pass shell: bash simply which should still allow shellcheck to run.

Some other parts of homebrew-core CI have the explicit /bin/bash to avoid Homebrew bash which some tests may install, so those are unavoidable.

[carlocab]

This should be ready to merge.

[MikeMcQuaid]

Thanks @carlocab!