Static mapping

[andrew-tpz]

For now we have to create mapper instance:

    final mapper = SomeMapperImpl();
    final entities = models.map(mapper.fromModel);

It would be greate to use mappers as static

    final entities = models.map(SomeMapper.fromModel);

Something like this:

@Mapper()
abstract class EntityMapper {
  static Entity fromModel(Model model) => _$EntityMapperFromModel(model);
}

[smotastic]

Hi andrew,

I really like the idea, and it should be relatively simple to implement.
If the generator finds a static method, just create the method as you suggested in a static manner.

Feel free to post a PR on this issue.
Otherwise I'll see if I get some time in the next weeks

[smotastic]

Hi, i just merged #55 which will enable you to define static methods in this manner.

@Mapper()
abstract class StaticMappingMapper {
  StaticMappingTarget fromSourceNormal(StaticMappingSource source);

  static StaticMappingTarget fromSourceStatic(StaticMappingSource source) =>
      _$fromSourceStatic(source);
}

See also this example https://github.com/smotastic/smartstruct/tree/develop/example/lib/static_mapping

I plan to release this in the next version (1.2.7) which will come either this weekend, or beginning of next week.

[petrnymsa]

Hi this change broke mapping with custom function which returns Enum.

Consider for example mapping from String to Enum value.

Modified field_mapping.dart example

enum DogType { happy, angry }

// TARGET

class Dog {
  final String name;
  final String breed;
  final int age;
  final DogType dogType;

  Dog(this.name, this.breed, this.age, this.dogType);
}

// SOURCE

class DogModel {
  final String dogName;
  final String breed;
  final int dogAge;
  final String dogType;

  DogModel(this.dogName, this.breed, this.dogAge, this.dogType);
}

/// Mapper showcasing explicit fieldmapping in case fields do not match their respective fieldnames
@Mapper()
abstract class DogMapper {
  static DogType _mapDogType(DogModel model) {
    if (model.dogType == 'angry') return DogType.angry;

    return DogType.happy;
  }

  @Mapping(source: 'dogName', target: 'name')
  @Mapping(source: 'dogAge', target: 'age')
  @Mapping(source: _mapDogType, target: 'dogType')
  Dog fromDogModel(DogModel model);
}

generates

// GENERATED CODE - DO NOT MODIFY BY HAND

part of 'field_mapping.dart';

// **************************************************************************
// MapperGenerator
// **************************************************************************

class DogMapperImpl extends DogMapper {
  DogMapperImpl() : super();

  @override
  Dog fromDogModel(DogModel model) {
    final dog = Dog(
        model.dogName, model.breed, model.dogAge, DogMapper._mapDogType(model));
    return dog;
  }
}

DogType _$_mapDogType(DogModel model) {
  final dogtype = DogType();
  return dogtype;
}

which fails to compile Enums can't be instantiated. Try using one of the defined constants.

[luissalgadofreire]

I also noticed the new bug when mapping enum, as described above. This is preventing me from upgrading to analyzer ^4.0.0. Is this getting fixed by Fix/41?

[smotastic]

Will be fixed with #68