anchor.diff:  
     Directory _getSubDir(Directory dir, String name) =>
         new Directory(path.join(dir.path, name));
  +
  +  String _getHostedPackageDirectoryName() {
  +    final url = Uri.parse(
  +        Platform.environment['PUB_HOSTED_URL'] ?? 'https://pub.dartlang.org');
  +    return url.host;
  +  }
   }
   
   /// A Dart application; a package with an entry-point, available via `pub global
  
positive.code:     _packageRefs = <PackageRef>[];
  
      Directory dartlangDir = new Directory(
          path.join(location.path, 'hosted', _hostedPackageDirectoryName));
      if (dartlangDir.existsSync()) {
        _packageRefs.addAll(dartlangDir
            .listSync()
  
negative.code: 
    List<Application> _applications;
    List<PackageRef> _packageRefs;
  
    /// Create a pubcache instance. [dir] defaults to the default platform pub
    /// cache location.
  