commit-message-check.yml

# Shells out to .husky/commit-msg (not a reimplemented regex) so local and CI
# rules can't drift: `sh .husky/commit-msg <message-file>`, exit code = verdict.
name: Commit Message Check
on:
  pull_request:
concurrency:
  group: commit-message-check-${{ github.ref }}
  cancel-in-progress: true
permissions:
  contents: read
jobs:
  run-commit-message-check:
    runs-on: ubuntu-latest
    timeout-minutes: 5
    steps:
      - name: Checkout repository
        uses: actions/checkout@v7
        with:
          fetch-depth: 0
      - name: Validate commit subjects
        env:
          BASE_SHA: ${{ github.event.pull_request.base.sha }}
          HEAD_SHA: ${{ github.event.pull_request.head.sha }}
        run: |
          set -uo pipefail
          MERGE_BASE=$(git merge-base "$BASE_SHA" "$HEAD_SHA")
          FAILED=0
          for SHA in $(git rev-list --no-merges "$MERGE_BASE..$HEAD_SHA"); do
            git log -1 --format=%B "$SHA" > "$RUNNER_TEMP/msg.txt"
            if ! sh .husky/commit-msg "$RUNNER_TEMP/msg.txt"; then
              echo "::error::$SHA — invalid commit subject (see log for the rule violated)"
              FAILED=1
            fi
          done
          exit $FAILED