name: Lint

on:
  push:
  pull_request:

jobs:
  clang-format:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
        with:
          fetch-depth: 0
      # Pin: format results differ across clang-format versions.
      - run: pip install --user clang-format==23.1.1 && echo "$HOME/.local/bin" >> "$GITHUB_PATH"
      - name: Check changed lines
        run: |
          if [ "${{ github.event_name }}" = "pull_request" ]; then
            BASE="${{ github.event.pull_request.base.sha }}"
          elif [ "${{ github.event.before }}" != "" ] && [ "${{ github.event.before }}" != "0000000000000000000000000000000000000000" ]; then
            BASE="${{ github.event.before }}"
          else
            BASE="$(git merge-base HEAD "origin/${{ github.event.repository.default_branch }}" || echo HEAD~1)"
          fi
          ./tools/lint.sh "$BASE"