pull-request-bot.yml

name: open-pr-dev-to-main

on:
  push:
    branches: [dev]

permissions:
  contents: read

concurrency:
  group: open-pr-dev-to-main
  cancel-in-progress: true

jobs:
  pr:
    runs-on: ubuntu-latest
    environment: submit-pull-request
    steps:
      - name: App token
        id: app
        uses: actions/create-github-app-token@fee1f7d63c2ff003460e3d139729b119787bc349 # v2.2.2
        with:
          app-id: ${{ secrets.PR_BOT_APP_ID }}
          private-key: ${{ secrets.PR_BOT_PRIVATE_KEY }}
          repositories: ${{ github.event.repository.name }}
          permission-pull-requests: write
          permission-contents: read

      - name: Checkout
        uses: actions/checkout@11d5960a326750d5838078e36cf38b85af677262 # v4
        with:
          fetch-depth: 0

      - name: Create or update PR
        env:
          GH_TOKEN: ${{ steps.app.outputs.token }}
        run: |
          set -euo pipefail
          git fetch origin main dev
          N=$(git rev-list --count origin/main..origin/dev)
          [ "$N" -gt 0 ] || { echo "dev is level with main; nothing to open"; exit 0; }
          FIRST=$(git log -1 --format=%s origin/dev)
          if [ "$N" -eq 1 ]; then
            TITLE="$FIRST"
          else
            TITLE="dev to main: $FIRST (+$((N-1)) more)"
          fi
          {
            echo "## $N commit(s) ahead of main"
            echo
            git log --reverse --format='### %s%n%n%b%n(%h)%n' origin/main..origin/dev
          } | head -c 60000 > body.md
          NUM=$(gh pr list --base main --head dev --state open --json number --jq '.[0].number // empty')
          if [ -n "$NUM" ]; then
            gh pr edit "$NUM" --title "$TITLE" --body-file body.md
          else
            gh pr create --base main --head dev --title "$TITLE" --body-file body.md
          fi