Incorrect "unmapped property" warning with inheritance

[jacobhampel]

We have some internal messages which extend a BaseClass. This BaseClass contains some variables for our database. These variables should be present in our DTOs.
To avoid ignoring the variables in every single mapper we're using a GenericConfig. In the GenericConfig no warnings were displayed. Neither when we compile the code nor at the IDE level.
Our GenericConfig looks like the following:

@MapperConfig(uses = DateToOffsetDateMapper.class,
        unmappedTargetPolicy = ReportingPolicy.ERROR,
        mappingInheritanceStrategy = MappingInheritanceStrategy.AUTO_INHERIT_FROM_CONFIG)
public interface GenericConfig {

    @Mapping(target = "storageId", ignore = true)
    @Mapping(target = "date", ignore = true)
    BaseClass genericMessageMapping(GenericDto dto); 
}

The GenericDto is an empty interface. All DTOs implements this interface.

The BaseClass looks like the following:

public class BaseClass
{
   private String storageId;
   private OffsetDateTime date;

   //getter and setter
}

Every mapper extends this config.

@Mapper(config = GenericConfig.class, uses = {})
public interface CarMapper  {
   Car map(CarDto dto);
}

In this example Car extends BaseClass and CarDto extends GenericDto.
Now my question: Why does the IDEA plugin shows me the error that I have unmapped properties at Car map(CarDto dto)?
If I compile the code no warnings are shown, which I think is correct.

Maybe you have an idea where I have to look.

[filiphr]

Currently we are not looking into the Mapper#config nor we apply inheritance for the mapping policies.

Edit: I didn't see that this issue is inthe correct place

[filiphr]

@jacobhampel if you are interested in adding this functionality to the plugin I can help you out

[Panossa]

Woah, this issue is old. Anyway, I have the same issue but slightly different. Given the example code above, I'd have something like:

@Mapping(target = "storageId", ignore = true)
@Mapping(target = "date", ignore = true)
GenericDto genericMessageMapping(OtherObject o); 

GenericDto inherits storageId and date from BaseClass, but this plugin marks both properties as unknown, even though they are in the target class.
(We don't have a mappingInheritanceStrategy in our project, but I would assume the default behavior of the plugin / of MapStruct to be able to use it like that, which it does when compiled.)

[thunderhook]

This seems to be the same issue reported in this comment.

[Panossa]

Might be, yeah. Although they get an error if they DON'T create a mapping, which I seemingly don't get.

[thunderhook]

So, I had another look at the issue. With the version 1.9.0 of the MapStruct plugin this issue is now resolved

public class BaseClass {
   public String storageId;
   public String date; // String and public for brewity
}

public class Car extends BaseClass {
}

public interface GenericDto {
}

public class CarDto implements GenericDto{
}

@MapperConfig(
    unmappedTargetPolicy = ReportingPolicy.ERROR,
    mappingInheritanceStrategy = MappingInheritanceStrategy.AUTO_INHERIT_FROM_CONFIG
)
public interface GenericConfig {

    @Mapping(target = "storageId", ignore = true) // no errors and references work
    @Mapping(target = "date", ignore = true) // no errors and references work
    BaseClass genericMessageMapping(GenericDto dto);
}

@Mapper(config = GenericConfig.class, uses = {})
public interface CarMapper  {

   Car map(CarDto dto); // plugin shows no errors
}

As soon as I comment out the @Mapping(target = "storageId", ignore = true), the CarMapper shows a warning.

So the original issue is resolved, therefore I close this issue.

@Panossa could you please provide a small reproducer (like I did above) in a separate issue?