Re: [PATCH] ci: avoid unnecessary builds

[Taylor Blau <me@ttaylorr.com>]

On Tue, Nov 08, 2022 at 09:18:21AM +0100, Johannes Schindelin wrote:
> > I played around with the following, but I can't quite get Actions to
> > like it. The error message I get (ref[1]) is something like:
> >
> >     The workflow is not valid. .github/workflows/main.yml (Line: 96, Col:
> >     27): Unexpected value 'needs.ci-config.outputs.skip_concurrent == 'yes''
> >     .github/workflows/main.yml (Line: 123, Col: 27): Unexpected value
> >     'needs.ci-config.outputs.skip_concurrent == 'yes''
>
> The reason is that what you are trying to do simply cannot work.

I was surprised that I couldn't get this to work, because to me it
seemed like the sort of thing that *should* be possible to do.

Indeed, it is, and I made a couple of mistakes in writing the workflow
file:

  - The expression for 'skip-in-progress' needed to be enclosed in
    '${{}}' markers.

  - It also needed to take into account the job name (and matrix
    information!) where relevant. And here we can't just use
    ${{github.job}}, since that is only available inside of the job
    steps.

To the last bullet point there, we unfortunately have to copy and paste
the job name, which seems like a limitation of the Actions workflow
parser to me.

I posted an alternative approach to this patch in [1], and I would be
very curious to hear your thoughts, if you have time!

Thanks,
Taylor

[1]: https://lore.kernel.org/git/cover.1667931937.git.me@ttaylorr.com/T/#t