@brianatgather sorry for the delayed response. Trying to process some of these older PRs.

This PR is good and makes sense---thanks your for your contribution. That said, I need to pass it to engineering to approve the parameter name, which is relevant to some planned changes.

In the meantime, I wanted to let you know (and anyone else with the use case of needing to override the build number), that this is available now through the use of Coveralls environment variables.

In this case, you'd want to set COVERALLS_SERVICE_NUMBER:

A common alternative build number used to tie all GitHub Actions workflows together is the commit SHA (${{ github.sha }}), so a configuration like the one below will override the default build number our action sources from the CI environment (ie. ${{ github.run_id }} from GitHub Actions):

    - name: Coveralls Parallel Upload
      uses: coverallsapp/github-action@v2
      env:
        COVERALLS_SERVICE_NUMBER: ${{ github.sha }} # default: ${{ github.run_id }}
      with:
        parallel: true
        flag_name: my-flag-name-1

In which case, you'll want to make sure to pass that, or whatever you used, to the "Parallel finished" step:

    - name: Coveralls Finished
      uses: coverallsapp/github-action@v2
      env:
        COVERALLS_SERVICE_NUMBER: ${{ github.sha }}
      with:
        parallel-finished: true
        carryforward: "my-flag-name-1,my-flag-name-2"

Hi @brianatgather, I moved your changes to PR #228, where I rebased it on top of main which now contains some tests.