anchor.diff:      List userList = [user, user2, user3];
       expect(
           utf8.decode(Formatter.serialize(
  -                Formatter.deserialize(Formatter.serialize(userList))))
  -            ,
  +            Formatter.deserialize(Formatter.serialize(userList)))),
           equals(utf8.decode(Formatter.serialize(userList))));
       expect(
           Formatter.serialize(
  
positive.code:     expect(Formatter.deserialize(Formatter.serialize("")), equals(""));
      expect(Formatter.deserialize(Formatter.serialize("c")), equals("c"));
      expect(Formatter.deserialize(Formatter.serialize("我")), equals("我"));
      expect(Formatter.deserialize(Formatter.serialize("我爱你")), equals('我爱你'));
      expect(Formatter.deserialize(Formatter.serialize("我爱五星红旗🇨🇳")),
          equals('我爱五星红旗🇨🇳'));
      expect(Formatter.deserialize(Formatter.serialize([1, 2, 3, 4, 5])),
          equals([1, 2, 3, 4, 5]));
  
negative.code:                 simple: true)
              .toString(),
          equals(Formatter.serialize(userList, simple: true).toString()));
    });
  }
  
  