check_license.yml

---
name: Check license

on:
  push:

jobs:
  check_license:
    name: Check license headers

    runs-on: ubuntu-latest

    steps:
    - uses: actions/checkout@v2
      with:
        fetch-depth: 0  # OR "2" -> To retrieve the preceding commit.

    - name: Get changed files
      id: changed-files
      uses: tj-actions/changed-files@v1.1.2

    - name: Check copyright header in added files
      shell: bash
      run: |
        missing=0
        if [ -z "${{ steps.changed-files.outputs.added_files }}" ]; then
          exit 0
        fi
        for file in "${{ steps.changed-files.outputs.added_files }}"; do
          echo "$file was modified"
          if ! egrep -q '(Facebook, Inc(\.|,)? and its affiliates)|([0-9]{4}-present(\.|,)? Facebook)|([0-9]{4}(\.|,)? Facebook)' $file; then
            echo "Missing copyright header in $file"
            missing=$(expr $missing + 1)
          fi
        done
        exit $missing