pr.yml

name: Comment diff in PR
permissions:
  pull-requests: write
on:
  workflow_dispatch:
  pull_request:
    paths:
      - .github/workflows/**
      - "**.nix"
      - "flake.lock"

jobs:
  build:
    if: github.head_ref == 'update_flake_lock_action'
    name: "Build ${{ matrix.target }}"
    runs-on: ${{ matrix.os }}
    strategy:
      fail-fast: false
      matrix:
        include:
          - os: ubuntu-latest
            target: william
          - os: ubuntu-latest
            target: nixos-local
          - os: macos-latest
            target: william-alt
          - os: macos-latest
            target: macos-local

    steps:
      - uses: actions/checkout@v4
        with:
          fetch-depth: 0

      - name: Install nix
        uses: cachix/install-nix-action@V27
        with:
          install_url: https://releases.nixos.org/nix/nix-2.18.2/install
          extra_nix_config: |
            experimental-features = nix-command flakes
            access-tokens = github.com=${{ secrets.GITHUB_TOKEN }}
            accept-flake-config = true

      - uses: cachix/cachix-action@v15
        with:
          name: williamhsieh
          extraPullNames: nix-community
          skipPush: true
          authToken: '${{ secrets.CACHIX_AUTH_TOKEN }}'

      - name: Free Disk Space (Ubuntu)
        if: ${{ matrix.os == 'ubuntu-latest' }}
        uses: jlumbroso/free-disk-space@main

      - name: Garbage collect build dependencies
        run: nix-collect-garbage

      - name: Fetch old system profile
        run: nix build github:WilliamHsieh/dotfiles#top.${{ matrix.target }} -v --log-format raw --profile ./old-profile

      - name: Add new system to profile
        run: |
          set -o pipefail
          nix build .#top.${{ matrix.target }} --profile ./new-profile --show-trace --fallback -v --log-format raw > >(tee stdout.log) 2> >(tee /tmp/nix-build-err.log >&2)

      - name: Output build failure
        if: failure()
        run: |
          drv=$(grep "For full logs, run" /tmp/nix-build-err.log | grep -oE "/nix/store/.*.drv")
          if [ -n $drv ]; then
            nix log $drv
            echo $drv
          fi
          exit 1

      - name: Diff profile
        id: diff
        run: |
          echo "diff<<EOF" >> "${GITHUB_OUTPUT}"
          nix run nixpkgs#nvd diff ./old-profile ./new-profile >> "${GITHUB_OUTPUT}"
          echo "EOF" >> "${GITHUB_OUTPUT}"

      - name: Comment report in pr
        uses: marocchino/sticky-pull-request-comment@v2
        with:
          hide_and_recreate: true
          hide_classify: "OUTDATED"
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
          header: ".#top.${{ matrix.target }}"
          message: |
            ### Report for `${{ matrix.target }}`

            <details>
            <summary> Version changes </summary> <br>
            <pre> ${{ steps.diff.outputs.diff }} </pre>
            </details>