anchor.diff:  
   @Injectable()
   class UserService {
  -  UserService(this._http);
  +  UserService(this._http, this._api);
   
     final Client _http;
  -  final api.UsersApi _usersApi = new api.UsersApi();
  +  final API _api;
   
     Future<User> me() async {
       final userMe = '''
  
positive.code:   }
  
    Future<User> update(User user) async {
      final userUpdate = '''
  mutation updateUser(\$id: ID!, \$user: UpdatedUser!) {
    user: updateUser(id: \$id, user: \$user) {
      id
      email
      username
      name
      createdAt
      updatedAt
    }
  }
  ''';
  
      var payload = json.encode({
        'query': userUpdate,
        'variables': {
          'id': user.id,
          'user': {
            'name': user.name,
          },
        },
      });
  
      Response resp = await this._http.post('/api/query', body: payload);
  
      var body = json.decode(resp.body);
      return new User.fromJSON(body['data']['user']);
    }
  }
  
  
negative.code:   }
  
    Future<List<User>> list() async {
      List<api.User> list = await _api.users.listUsers();
  
      List<User> users = list.map((api.User user) {
        return User(
  