name: Checkpatch upon pull request

on:
  pull_request:
    branches:
      - master

jobs:
  checkpatch:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout code
        uses: actions/checkout@main
        with:
          ref: ${{github.event.pull_request.head.sha}}
          fetch-depth: 0

      - name: Download checkpatch.pl
        run: |
          curl https://raw.githubusercontent.com/torvalds/linux/master/scripts/checkpatch.pl -o checkpatch.pl
          curl https://raw.githubusercontent.com/torvalds/linux/master/scripts/spelling.txt -o spelling.txt
          curl https://raw.githubusercontent.com/torvalds/linux/master/scripts/const_structs.checkpatch -o const_structs.checkpatch
          chmod +x checkpatch.pl

      - name: Run checkpatch.pl
        run: |
          ignore=(
            MISSING_SIGN_OFF
            EMAIL_SUBJECT
            UNKNOWN_COMMIT_ID
            NO_AUTHOR_SIGN_OFF
            COMMIT_LOG_USE_LINK
            BAD_REPORTED_BY_LINK
            FILE_PATH_CHANGES
            SPDX_LICENSE_TAG
            LINUX_VERSION_CODE
            CONSTANT_COMPARISON
            NEW_TYPEDEFS
            SPACING
          )
          ignore_str=${ignore[*]}

          base_commit=${{github.event.pull_request.base.sha}}
          commits=$(git log --pretty=format:"%h" $base_commit..HEAD)
          err=0

          for commit in $commits; do
            echo "Running checkpatch.pl for commit $commit"
            echo "========================================"
            git format-patch -1 --stdout $commit | ./checkpatch.pl --no-tree --show-types --strict --ignore="${ignore_str// /,}" - || err=1
            echo
          done

          exit $err