anchor.diff:  
     Version get latestVersion => _latestVersion;
   
  -  VizPackage._(String path, this.name, this.version, Set<Dependency> deps)
  -      : dependencies = new UnmodifiableSetView(deps),
  -        this.path = p.normalize(path);
  +  VizPackage._(this.name, this.version, Set<Dependency> deps)
  +      : dependencies = new UnmodifiableSetView(deps);
   
     static Future<VizPackage> forDirectory(String path,
         {bool flagOutdated: false}) async {
  
positive.code:     return package;
    }
  
    String toString() => '$name @ $path';
  
    int compareTo(VizPackage other) {
      return name.compareTo(other.name);
  
negative.code: import 'util.dart';
  
  class VizPackage extends Comparable {
    final String name;
    final Version version;
    final Set<Dependency> dependencies;
  