format-check.yml

name: Formatting check

on: [pull_request]

jobs:
  formatting-check:
    name: Formatting check
    runs-on: ubuntu-24.04

    steps:
    - uses: actions/checkout@v4
      with:
        # To get a diff from the PR we need to fetch 2 commits.
        # The checkout action will create a merge commit as {{ github.sha }}.
        fetch-depth: 2

    - name: Install dependencies
      run: |
        sudo apt-get update
        sudo apt-get install -yqq clang-format

    - name: Format check
      id: format-check
      run: |
        git diff -U0 --no-color ${{ github.sha }}^ -- '*.cpp' '*.c' '*.h' '*.hpp' |
          /usr/share/clang/clang-format-16/clang-format-diff.py -p1 > clang-format.patch

        # Check if patch is not empty
        if [ -s clang-format.patch ]; then
          echo "###############################################################"
          echo "# Format checks failed!"
          echo "# A patch has been uploaded as an artifact and is shown below."
          echo "###############################################################"

          # Show patch
          cat clang-format.patch

          exit 1
        fi

    - name: Upload format fixes patch 
      uses: actions/upload-artifact@v4
      if: ${{ failure() && steps.format-check.outcome == 'failure' }}
      with:
        name: clang-format.patch
        path: clang-format.patch
        if-no-files-found: ignore