.github/workflows/files-changed.yml

name: Generate Changed Files JSON

on:
  pull_request:
    types:
      - opened
      - synchronize

jobs:
  generate-json:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout code
        uses: actions/checkout@v3

      - name: Fetch base commit and origin/master
        # Fetch what to compare the commit against
        run: |
          git fetch --no-tags --prune --depth=1 origin ${{ github.event.pull_request.base.sha }}
          git fetch --no-tags --prune --depth=1 origin master
          echo "FLUTTER_ENGINE_VERSION=${{ github.event.pull_request.base.sha }}" >> "$GITHUB_ENV"

      - name: Initialize Dart SDK
        # This downloads the version of the Dart SDK for the current platform.
        run: |
          ./bin/dart --version
          cd dev/tools && ../../bin/dart pub get

      - name: Write changed files to a JSON file
        run: |
          ./bin/dart run dev/tools/bin/get_files_changed.dart --since="${{ github.event.pull_request.base.sha }}" > changed_files.json

      - name: Upload artifact
        uses: actions/upload-artifact@v4
        with:
          name: changed-files
          path: changed_files.json