anchor.diff:  final _userToOauth = <String, String>{};
   final _oauthToUser = <String, String>{};
   final _invalidUsers = Set<String>();
  +final _packages = <String>{};
  +final _packagesWithVersion = <String>{};
   int _packageChecked = 0;
  +int _versionChecked = 0;
   
   Future main(List<String> args) async {
     final argv = _argParser.parse(args);
  
positive.code:     print('  .. $_packageChecked done (${p.name})');
    }
  }
  
negative.code: }
  
  Future _checkPackage(Package p) async {
    _packages.add(p.name);
    if (p.uploaders == null || p.uploaders.isEmpty) {
      _problems.add('Package(${p.name}) has no uploaders.');
    }
  