name: Make PNG
run-name: ${{ gitea.actor }} is recording the PNG output.

on: push

jobs:
  build-app:
    runs-on: linux_amd64
    steps:
      - name: Checkout current
        uses: actions/checkout@v4
        with:
          path: curr
          submodules: recursive
      - name: Checkout previous
        uses: actions/checkout@v4
        with:
          path: prev
          fetch-depth: 2
          submodules: recursive
      - run: cd prev && git checkout HEAD^
      - name: Build current
        run: cmake -S curr -B curr/build && cmake --build curr/build
      - name: Build previous
        run: cmake -S prev -B prev/build && cmake --build prev/build
      - name: Generate PNG file for curr
        run: cd curr/build/tests && xvfb-run ./test-basic
      - name: Generate PNG file for prev
        run: cd prev/build/tests && xvfb-run ./test-basic
      - name: Compare PNG files
        run: diff curr/build/tests/image.png prev/build/tests/image.png