diff-pr.yml

name: Detect differences (PR only)

on:
  pull_request:
    types: [opened, synchronize, reopened]

jobs:

  diff:
    runs-on: ubuntu-latest
    env:
      DOTNET_NOLOGO: true
    permissions:
      pull-requests: write

    steps:
    - uses: actions/checkout@v4
      with:
        submodules: true
        fetch-depth: 100

    # The GitHub checkout action leaves the repo in a slightly awkward
    # state. This tidies it up.
    - name: Set up git branches
      run: |
        git checkout -b pr-head
        git checkout -b main ${{ github.event.pull_request.base.sha }}
        git checkout pr-head

    - name: Setup .NET 6.0
      uses: actions/setup-dotnet@v4
      with:
        dotnet-version: 6.0.x

    - name: Detect PR changes
      env:
        ALLOW_BREAKING_CHANGES: ${{contains(github.event.pull_request.labels.*.name, 'allow breaking changes')}}
      run: |
        if [[ $ALLOW_BREAKING_CHANGES == "true" ]]
        then
          SCRIPT_OPTION=--allow-breaking-changes
        fi
        
        # Run the diff, recording the results
        echo "**Pull request diff results**" >> diff.txt
        set -o pipefail
        ./detect-pr-changes.sh $SCRIPT_OPTION 2>&1 | tee -a diff.txt        
        set +o pipefail

    # The purpose of (success() || failure()) in the condition is to
    # make sure we post a comment on both success and failure, but *not*
    # if the job is cancelled.
    - name: Post diff as a comment for branches on target fork
      if: (success() || failure()) && github.event.pull_request.head.repo.full_name == github.repository
      run: |
        ./prepare-release.sh add-pr-comment diff.txt \
           ${{github.event.pull_request.number }} \
           ${{secrets.GITHUB_TOKEN}}