anchor.diff:    /// The [PackageGraph] for the current program.
     final PackageGraph _packageGraph;
   
  -  /// Shared [AssetWriter] with [_buildImpl]
  -  final AssetWriter _writer;
  -
     /// A future that completes when the current build is done.
     Future<BuildResult> _currentBuild;
     Future<BuildResult> get currentBuild => _currentBuild;
  
positive.code: import 'package:watcher/watcher.dart';
  
  import '../asset/id.dart';
  import '../asset/writer.dart';
  import '../asset_graph/graph.dart';
  import '../asset_graph/node.dart';
  import '../logging/logging.dart';
  
negative.code:   WatchImpl(BuildOptions options, PhaseGroup phaseGroup)
        : _directoryWatcherFactory = options.directoryWatcherFactory,
          _debounceDelay = options.debounceDelay,
          _packageGraph = options.packageGraph,
          _buildImpl = new BuildImpl(options, phaseGroup);
  
  