anchor.diff:      }
       return Place.none();
     }
  -
  -  static List<String> _computeRootPaths(String rootPath, bool corpus) {
  -    var roots = <String>[];
  -    if (!corpus) {
  -      roots.add(rootPath);
  -    } else {
  -      for (var child in io.Directory(rootPath).listSync()) {
  -        if (child is io.Directory) {
  -          roots.add(path.join(rootPath, child.path));
  -        }
  -      }
  -    }
  -    return roots;
  -  }
  -}
  +}
  
positive.code: import 'package:analyzer/src/generated/engine.dart';
  import 'package:analyzer/src/services/available_declarations.dart';
  import 'package:args/args.dart';
  import 'package:path/path.dart' as path;
  
  import 'metrics_util.dart';
  import 'utils.dart';
  
negative.code: /// Create a parser that can be used to parse the command-line arguments.
  ArgParser createArgParser() {
    ArgParser parser = ArgParser();
    parser.addOption(
      'help',
      abbr: 'h',
  