Feature Request: default values

[mars3142]

I would like to use the serializer/deserializer for built value classes, but if the input data doesn't contain all values, it would be helpful to initialize the values with a value, instead of null - so every property needs to be marked as @nullable which is bad behavior..

What's the best way to do it, if it's already possible? If it's not possible a new attribute for @BuiltValueField like default would be fine.

[davidmorgan]

You can use _initializeBuilder as shown here: #212 (comment)

It's not in the docs yet, sorry.

[mars3142]

Did you read my request complete? I want to use:

final object = serializers.deserializeWith(MyClass.serializer, json);

So it's not possible to use it that way. Right?

[davidmorgan]

Yes, it will work, the deserializer uses builders so setting a default on the builder affects it.

[mars3142]

@daohoangson So this code eg will do the trick?

factory Account([updates(AccountBuilder b)]) =>
  new _$Account((b) => b..name = 'default'..update(updates));

[davidmorgan]

Not the factory--the initializeBuilder part

 static void _initializeBuilder(MessageBuilder builder) => builder
    ..id = ''
    ..userId = ''
    ..content = ''
    ..urlMedia = ''
    ..createdAt = DateTime(1970, 1, 1)
    ..type = MessageType.none
    ..localId = '';

[davidmorgan]

Should be documented as part of #1051