format.yml

name: Run Clang-Format Check

on:
    push:
      branches: [ "master" ]
    pull_request:
      branches: [ "master" ]

jobs:
  clang-format-check:
    runs-on: ubuntu-latest
    steps:
      - name: Install Python and clang-format to get newer version
        run: |
          python3 -m pip install --upgrade pip
          pip install clang-format==19.1.3

      - name: Checkout the code
        uses: actions/checkout@v4
        with:
          fetch-depth: 0 #ensure fetch of pr branch before commit

      - name: Fetch latest master branch
        run: git fetch origin master

      - name: Set up Clang-Format
        run: sudo apt-get install -y clang-format

      - name: Check formatting with Clang-Format
        run: |
          set +e # this turn off exit-on-error
          
          # searches for all src files that are modified in comparison to origin/master
          MODIFIED_FILES=$(git diff --name-only origin/master...HEAD | grep -E '\.(c|h|cpp|hpp)$')

          # track format errors
          FORMAT_ERRORS=0

          if [[ -n "$MODIFIED_FILES" ]]; then 
            echo "modified files found!"
            clang-format --version

            # check if formatted correctly
            for file in $MODIFIED_FILES; do
              echo "Checking file: $file"

              # Capture the output of clang-format check
              OUTPUT=$(clang-format --dry-run -Werror "$file" 2>&1)

              # Check if there was an error
              if [[ $? -ne 0 ]]; then
                echo "Formatting issue found in $file:"
                echo "$OUTPUT" # print clang-format error message
                FORMAT_ERRORS=1
              fi
            done

            # Exit with an error if any formatting issues were found
            if [[ $FORMAT_ERRORS -ne 0 ]]; then
              echo "Formatting issues detected. Please run clang-format $(clang-format --version) to fix the issues."
              exit 1
            fi
          else 
            echo "no modified files found!"
          fi
          exit 0