[Bug]: Empty pr_branch output variable

[kdeldycke]

Is there an existing issue for this?

• I have searched the existing issues

Describe the bug

It looks like the new pr_branch variable output (implemented by #472 / #473) is not set if there is already a PR previously created by actions-template-sync.

Expected Behavior

I expect the pr_branch variable to always be set to the active / unmerged PR that is tracked an maintained by actions-template-sync.

Current Behavior

I have a workflow that essentially looks like this:

(...)

jobs:

  awesome-template-sync:
    runs-on: ubuntu-22.04
    steps:
      - uses: actions/checkout@v4.1.1

      - name: Sync from template repo
        id: template_sync
        uses: AndreasAugustin/actions-template-sync@v1.8.0
        with:
          # We need custom PAT with workflows permissions so we can update all the boilerplate .github files from
          # awesome-template.
          github_token: ${{ secrets.WORKFLOW_UPDATE_GITHUB_PAT || secrets.GITHUB_TOKEN }}
          source_repo_path: kdeldycke/awesome-template
          pr_title: "[sync] Updates from `awesome-template` repository"
          pr_commit_msg: "[sync] Updates from `awesome-template` repository"
          pr_branch_name_prefix: "sync-awesome-template"
          pr_labels: "📚 documentation"
          is_pr_cleanup: true

      - name: Print PR branch ID
        run: |
          echo "PR branch ID: ${{ steps.template_sync.outputs.pr_branch }}"

      (...)

The full workflow code is available at: https://github.com/kdeldycke/awesome-billing/blob/b4686574a1a328f001ca1410f65b6137f990763d/.github/workflows/docs.yaml#L16-L59

Its execution log is available at: https://github.com/kdeldycke/awesome-billing/actions/runs/8113301740/job/22199139632

On execution, you can find that the step printing the pr_branch variable returns nothing:

This is probably an edge-case because there is already an unmerged (and conflicting) PR that was previously created by actions-template-sync:

I expect here actions-template-sync should identify the already existing sync-awesome-template_d48d756 PR and branch, update it, and return its ID in pr_branch variable.

Note that the behavior is the same wether is_pr_cleanup parameter is true or false.

Steps To Reproduce

No response

Possible Solution

No response

Additional Information/Context

This was encounter while playing with 1.8.0 to implement a temporary workaround for #467.

Template sync version Version

1.8.0

[AndreasAugustin]

@kdeldycke thanks for the report. Indeed I forgot to handle some 'edge-cases' (thanks for the hint within the description).
Sorry for that 🥷

The edge-case in your case is the following:

• The action is checking if the branch is already available remotely (the prefix is the commit short ID) and exiting.
• The output definition is with v1.8.0 at the end of the action and not done for exit cases

Your action log part:

::info::Missing env variable 'UPSTREAM_BRANCH' setting to remote default main
::info::current git hash: b4686574a1a328f001ca1410f65b6137f990763d
Check new changes
  a5d4c1b6d368ba257[28](https://github.com/kdeldycke/awesome-billing/actions/runs/8113301740/job/22199139632#step:4:30)94b0e93ac16cd65a6f02e	refs/heads/sync-awesome-template_d48d756
  ::warn::Git branch 'sync-awesome-template_d48d756' exists in the remote repository

related code part src/sync_template.sh line 51

function check_branch_remote_existing() {
  git ls-remote --exit-code --heads origin "${NEW_BRANCH}" || BRANCH_DOES_NOT_EXIST=true

  if [[ "${BRANCH_DOES_NOT_EXIST}" != true ]]; then
    warn "Git branch '${NEW_BRANCH}' exists in the remote repository"
# following line will be added with v1.8.1    
# set_github_action_outputs
    exit 0
  fi
}

With v1.8.1 Your case should be fixed (at least my tests are green).

[kdeldycke]

Wow, thanks @AndreasAugustin for the incredibly fast investigation and fix! I can confirm v1.8.1 fix the issue and pr_branch is properly set.

You can check the proof here: https://github.com/kdeldycke/awesome-billing/actions/runs/8122438292/job/22201872306#step:5:5