Unable to add directories to path when overriding workflow shell

[Jesse-Bakker]

When appending to the file pointed to by $GITHUB_PATH, gha will add those directories to the path in subsequent actions steps. When using runs-on, this doesn't work. This means that actions that install tools, like action/setup-python, will not have the desired effect, as the tools they install will not be on the path in subsequent job steps.

[crohr]

Hi @Jesse-Bakker, that seems surprising to me. Do you have an example workflow I could use to reproduce?

[Jesse-Bakker]

@crohr I narrowed it down to overriding the shell in the workflow. The following works correctly on github-hosted runners but has the wrong path on runs-on:

on:
  pull_request:
jobs:
  test-runson:
    runs-on: [ runs-on,"runner=4cpu-linux-x64", "run-id=${{ github.run_id }}" ]
    defaults:
      run:
        shell: bash -leo pipefail {0}
    steps:
      - run: echo "/opt/" >> $GITHUB_PATH
      - run: echo "$PATH"

[crohr]

That's great thanks, and would you have the accompanying step that shows action/setup-python not having the intended effect?

[Jesse-Bakker]

@crohr Not right now (not at my computer at the moment), but what it comes down to is that it writes some paths in the tool cache to the $GITHUB_PATH file and those paths don't end up on the $PATH in subsequent steps.

[crohr]

@Jesse-Bakker thanks, I've indeed reproduced the issue. Can you confirm this only happens when overriding the default shell? Any specific reason to override it?

[alecmocatta]

We've not encountered this, but we similarly override the default shell to make behaviour and error handling stricter:

shell: bash --noprofile --norc -o errexit -o nounset -o pipefail -o xtrace -O nullglob -O dotglob {0}

[Jesse-Bakker]

@Jesse-Bakker thanks, I've indeed reproduced the issue. Can you confirm this only happens when overriding the default shell? Any specific reason to override it?

I am checking in with colleagues about why we override the shell.

I have a suspicion that the problem might be in our shell override omitting the --norc and --noprofile flags. I will check if specifying those ameliorates the problem for us tomorrow.

[Jesse-Bakker]

@crohr the problem was actually with the -l flag (-l Make bash act as if it had been invoked as a login shell). Without that the path works correctly. I don't think we actually need that flag, so I'm going to remove it from our pipelines for now.
Would be great if that eventually works like on github-hosted runners, but it's not a high priority for us right now.

Thank you for the quick response and thanks to you, Alec, for providing your shell override, comparing to which made debugging a lot easier!