anchor.diff:          refreshToken: data['refresh_token'],
           scopes: data['scopes'],
           lifeSpan: data['life_span'],
  -        application: data['application'] == null
  -            ? null
  -            : (data['application'] is Application
  -                ? data['application']
  -                : new Application.fromJson(data['application'])),
           createdAt: data['created_at'] is DateTime
               ? data['created_at']
               : (data['created_at'] is String
  
positive.code:         'refresh_token': refreshToken,
          'scopes': scopes,
          'life_span': lifeSpan,
          'application': application,
          'created_at': createdAt == null ? null : createdAt.toIso8601String(),
          'updated_at': updatedAt == null ? null : updatedAt.toIso8601String()
        };
  
negative.code:   int lifeSpan;
  
    @override
    DateTime createdAt;
  
    @override
  