set-pr-title.yml

name: Set PR Title to First Commit Message

on:
  pull_request:
    types: [opened, synchronize]

jobs:
  set-pr-title:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout code
        uses: actions/checkout@v2

      - name: Get first commit message
        run: echo "FIRST_COMMIT_MESSAGE=$(git log --format=%B -n 1 $(git rev-list --max-parents=0 HEAD))" >> $GITHUB_ENV

      - name: Update PR title
        run: |
          gh pr edit "$PR_NUMBER" --title "$FIRST_COMMIT_MESSAGE"
        env:
          FIRST_COMMIT_MESSAGE: ${{ env.FIRST_COMMIT_MESSAGE }}
          PR_NUMBER: ${{ github.event.pull_request.number }}