anchor.diff:        }
       }
       resolvers.add(new FileUriResolver());
  -    return new SourceFactory(resolvers, packages);
  +    return new SourceFactory(resolvers);
     }
   
     /// Convert the given [sourcePath] (which may be relative to the current
  
positive.code:   /// Convert [sourcePath] into an absolute path.
    static String _normalizeSourcePath(String sourcePath) {
      return path.normalize(new File(sourcePath).absolute.path);
    }
  }
  
  
negative.code:       new DartUriResolver(sdk)
      ];
  
      if (options.packageConfigPath != null) {
        String packageConfigPath = options.packageConfigPath;
        Uri fileUri = new Uri.file(packageConfigPath);
        try {
          File configFile = new File.fromUri(fileUri);
          List<int> bytes = configFile.readAsBytesSync();
          /*Map<String, Uri> map = */pkgfile.parse(bytes, fileUri);
          // TODO(pquitslund): plug into new resolver once implemented
          // https://github.com/dart-lang/sdk/issues/23615
        } catch (e) {
          printAndFail(
              'Unable to read package config data from $packageConfigPath: $e');
        }
        printAndFail(
            'Package config files are not supported yet. For status see: https://github.com/dart-lang/sdk/issues/23373');
      } else if (options.packageRootPath != null) {
        Map<String, List<fileSystem.Folder>> packageMap =
            _PackageRootPackageMapBuilder.buildPackageMap(
                options.packageRootPath);
        if (packageMap != null) {
          resolvers.add(new SdkExtUriResolver(packageMap));
        }
        JavaFile packageDirectory = new JavaFile(options.packageRootPath);
        resolvers.add(new PackageUriResolver([packageDirectory]));
      } else {
        PubPackageMapProvider pubPackageMapProvider =
            new PubPackageMapProvider(PhysicalResourceProvider.INSTANCE, sdk);
        PackageMapInfo packageMapInfo = pubPackageMapProvider.computePackageMap(
  