check-commit-hooks.yml

name: Check commit hooks

on: [push, pull_request]

jobs:
  commit_msg:
    runs-on: ubuntu-24.04
    steps:
    - uses: actions/checkout@v4
      with:
        fetch-depth: 0
    - name: Check
      run: |
        if [ -n "${GITHUB_BASE_REF}" ]; then
          # pull request, check head branch against base branch
          GITHUB_BEFORE="$(git ls-remote origin "${GITHUB_BASE_REF}" | cut -f1)"
        elif [[ "${GITHUB_REF}" != "refs/heads/main" ]]; then
          # workflow triggered from some branch other than main, assume that
          # the branch will eventually be merged into main
          GITHUB_BEFORE="$(git ls-remote origin refs/heads/main | cut -f1)"
        else
          # main branch, compare against previous state
          # (jq comes preinstalled on github runners)
          GITHUB_BEFORE="$(jq -r '.before' "${GITHUB_EVENT_PATH}")"
        fi

        # github interleaves stderr and stdout, redirect everything to stdout
        exec 2>&1

        export GIT_TOPLEVEL="$PWD"
        ./build-aux/ci/check-commit-hooks "${GITHUB_BEFORE}..${GITHUB_REF}"