merge-master-to-develop.yml

name: Sync develop branch

on:
    push:
        branches:
            # Keep this in sync with SYNC_SOURCE_BRANCH below.
            # GitHub Actions does not allow env values in trigger branch filters.
            - master

env:
    SYNC_SOURCE_BRANCH: master
    SYNC_TARGET_BRANCH: develop

permissions:
    contents: write

concurrency:
    group: ${{ github.workflow }}-${{ github.ref }}
    cancel-in-progress: false

jobs:
    sync-dev-branch:
        name: Merge master into develop branch
        # Keep this named after the GitHub repository.
        # GitHub Actions does not allow workflow env values in jobs.<job_id>.if.
        if: github.repository == 'phpbb-extensions/phpbb-ext-skeleton' && github.event.repository.fork == false
        runs-on: ubuntu-latest

        steps:
            - name: Check out repository
              uses: actions/checkout@v6
              with:
                  fetch-depth: 0

            - name: Configure Git author
              run: |
                  git config user.name "github-actions[bot]"
                  git config user.email "41898282+github-actions[bot]@users.noreply.github.com"

            - name: Merge source branch into target branch when clean
              run: |
                  if ! git ls-remote --exit-code --heads origin "${SYNC_TARGET_BRANCH}" > /dev/null 2>&1; then
                      echo "origin/${SYNC_TARGET_BRANCH} does not exist; skipping."
                      exit 0
                  fi

                  git fetch --no-tags --prune origin "${SYNC_TARGET_BRANCH}"
                  git checkout -B "${SYNC_TARGET_BRANCH}" "origin/${SYNC_TARGET_BRANCH}"

                  if git merge --no-edit "$GITHUB_SHA"; then
                      if [ "$(git rev-list --count "origin/${SYNC_TARGET_BRANCH}..HEAD")" -eq 0 ]; then
                          echo "${SYNC_TARGET_BRANCH} is already up to date."
                          exit 0
                      fi

                      git push origin "HEAD:${SYNC_TARGET_BRANCH}"
                  else
                      echo "${SYNC_SOURCE_BRANCH} could not be merged cleanly into ${SYNC_TARGET_BRANCH}; skipping."
                      if git rev-parse -q --verify MERGE_HEAD > /dev/null; then
                          git merge --abort
                      fi
                  fi