Pull Request の差分に対して swift-format でフォーマットして commit & push する GitHub Actions の設定

swift-format.yml

# Pull Request の差分に対して swift-format でフォーマットして commit & push する GitHub Actions の設定
name: swift-format

on:
  pull_request:
    branches:
      - main
    paths:
      - '**/*.swift'

jobs:
  format:
    runs-on: macos-14
    steps:
      - name: Install swift-format
        run: |
          brew install swift-format
      - name: PR commits + 1
        run: echo "PR_FETCH_DEPTH=$(( ${{ github.event.pull_request.commits }} + 1 ))" >> "${GITHUB_ENV}"
      - name: Checkout PR branch and all PR commits
        uses: actions/checkout@v4
        with:
          ref: ${{ github.event.pull_request.head.ref }}
          fetch-depth: ${{ env.PR_FETCH_DEPTH }}  # (PR の commits + 1) 個 checkout する
      - name: Find swift files to format
        run: |
          DELTA_FILES=$(git diff --name-only --diff-filter=ACMR  ${{ github.event.pull_request.base.sha }}...HEAD -- '*.swift')
          echo "SWIFT_FILES=$(echo ${DELTA_FILES})" >> "${GITHUB_ENV}"
      - name: Run swift-format on swift files
        if: ${{ env.SWIFT_FILES != '' }}
        run: |
          echo 'Formatting Swift files...'
          swift-format format --in-place --configuration .swift-format --parallel ${SWIFT_FILES[@]} || true
      - name: Commit and Push changes
        run: |
          git config --local user.name "${GITHUB_ACTOR}"
          git config --local user.email "${GITHUB_ACTOR}@users.noreply.github.com"
          git add .
          if git commit -m '[GitHub Actions] swift-format'; then
            echo 'Changes committed, pushing to repository...'
            git push origin HEAD:${{ github.head_ref }}
          else
            echo 'No changes to commit'
          fi