diff.yaml

name: Diff

on:
  pull_request:

jobs:
  diff:
    runs-on: ubuntu-latest
    permissions:
      pull-requests: write
    steps:
      - name: Checkout base
        uses: actions/checkout@v4
        with:
          ref: '${{ github.event.pull_request.base.sha }}'
          path: base
      - name: Checkout head
        uses: actions/checkout@v4
        with:
          path: head

      # https://stackoverflow.com/a/73596568
      - name: Setup to skip ksops decryption
        run: sudo ln -s /bin/true /usr/local/bin/ksops

      - name: Install dyff
        run: |
          # TODO: Use upstream once https://github.com/homeport/dyff/pull/409 is merged?
          # curl -s -L https://git.io/JYfAY | bash
          curl -s -L https://git.io/JYfAY | ORG=motoki317 REPO=dyff bash

      - name: Build base
        working-directory: ./base
        run: ./build.sh
      - name: Build head
        working-directory: ./head
        run: ./build.sh

      - name: Diff
        id: diff
        run: |
          # With console colors
          ./head/diff.sh \
            base/.built \
            head/.built \
            --omit-header

          # Plaintext
          ./head/diff.sh \
            base/.built \
            head/.built \
            --omit-header --output github \
            > diff.txt

          echo 'diff<<EOF' >> $GITHUB_OUTPUT
          cat diff.txt >> $GITHUB_OUTPUT
          echo 'EOF' >> $GITHUB_OUTPUT

          echo '### Diff' >> $GITHUB_STEP_SUMMARY
          echo '```diff' >> $GITHUB_STEP_SUMMARY
          cat diff.txt >> $GITHUB_STEP_SUMMARY
          echo '```' >> $GITHUB_STEP_SUMMARY

      - if: ${{ steps.diff.outputs.diff != '' }}
        name: Add comment
        uses: mshick/add-pr-comment@v2
        with:
          message-id: "${{ github.event.pull_request.number }}"
          message-failure: Diff was not successful
          message: |
            ### Diff
            ```diff
            ${{ steps.diff.outputs.diff }}
            ```
      - if: ${{ steps.diff.outputs.diff == '' }}
        name: Add comment
        uses: mshick/add-pr-comment@v2
        with:
          message-id: "${{ github.event.pull_request.number }}"
          message-failure: Diff was not successful
          message: |
            ### Diff
            No diff detected!