name: Detect trailing whitespace

on:
  pull_request:
    branches:
      - master

jobs:
  whitespace:
    runs-on: ubuntu-20.04
    steps:
      - uses: actions/checkout@v2
      - name: Remove whitespace and check the diff
        run: |
          set -eu
          scripts/remove_trailing_whitespace.sh
          git diff >whitespace.patch
          cat whitespace.patch
          if [ $(wc -c <whitespace.patch) -ne 0 ] ; then
             echo " !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! "
             echo "You have trailing whitespace, please download the artifact"
             echo "and apply with git apply <whitespace.patch or"
             echo "run scripts/remove_trailing_whitespace.sh locally."
             echo " !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! "
             exit 1
          else
             echo "no trailing whitespace found, good!"
          fi
      - name: Archive whitespace patch
        uses: actions/upload-artifact@v2
        if: always()
        with:
          name: whitespace-patch
          path: |
            whitespace.patch
          if-no-files-found: ignore