name: pull-request
on:
  pull_request:
    types: [opened, reopened, synchronize]
jobs:
  check-fast-forward:
    runs-on: ubuntu-latest

    permissions:
      contents: read
      # We appear to need write permission for both pull-requests and
      # issues in order to post a comment to a pull request.
      pull-requests: write
      issues: write

    steps:
      - name: Checking if fast forwarding is possible
        uses: sequoia-pgp/fast-forward@v1
        with:
          merge: false
          # To reduce the workflow's verbosity, use 'on-error'
          # to only post a comment when an error occurs, or 'never' to
          # never post a comment.  (In all cases the information is
          # still available in the step's summary.)
          comment: on-error