When getting a related queryset, we combine the object's related queryset with the view's queryset. This ensures that any filtering on the viewset is also applied to the related viewset. These kinds of checks (with django-model-utils, maybe django-polymorphic) need to be tested.
This is a little harder to do with to-one relationships, since you can't intersect the queryset with a single instance. This requires getting the object, and refetching it with the viewset's queryset.
When getting a related queryset, we combine the object's related queryset with the view's queryset. This ensures that any filtering on the viewset is also applied to the related viewset. These kinds of checks (with django-model-utils, maybe django-polymorphic) need to be tested.
This is a little harder to do with to-one relationships, since you can't intersect the queryset with a single instance. This requires getting the object, and refetching it with the viewset's queryset.