anchor.diff:        usageException("Error: Input directory doesn't exist: ${dir.path}");
       }
   
  -    // Parse options.
  -    final options = [
  -      '--input=${dir.path}',
  -      '--output=${argResults['output-dir']}',
  -    ];
  -    if (argResults['validate-links']) {
  -      options.add('--validate-links');
  -    } else {
  -      options.add('--no-validate-links');
  -    }
  -
       // Specify where dartdoc resources are located.
       final resourcesPath =
           path.absolute(sdk.sdkPath, 'bin', 'resources', 'dartdoc', 'resources');
  -    options.add('--resources-dir=$resourcesPath');
  +
  +    // Build options.
  +    final options = [
  +      '--input=${dir.path}',
  +      '--output=${argResults['output']}',
  +      '--resources-dir=$resourcesPath',
  +      if (argResults['validate-links']) '--validate-links'
  +    ];
   
       final config = await parseOptions(pubPackageMetaProvider, options);
       if (config == null) {
  
positive.code: 
    DocCommand({bool verbose = false}) : super(cmdName, cmdDescription, verbose) {
      argParser.addOption(
        'output-dir',
        abbr: 'o',
        defaultsTo: path.join('doc', 'api'),
        help: 'Output directory',
      );
      argParser.addFlag(
        'validate-links',
        negatable: true,
        help: 'Display context aware warnings for broken links (slow)',
      );
    }
  
  
negative.code:       return 2;
      }
  
      // Call into package:dartdoc.
      if (verbose) {
        log.stdout('Using the following options: $options');
      }
      final packageConfigProvider = PhysicalPackageConfigProvider();
      final packageBuilder = PubPackageBuilder(
          config, pubPackageMetaProvider, packageConfigProvider);
  