PolymorphicTypeInvalid if primary key is the same...

[jedie]

It's possible to create objects with same primary keys. But it will be raise into:

polymorphic.models.PolymorphicTypeInvalid: ContentType XY for <class 'FooBar'> #XY does not point to a subclass!

So there is not unique_together contraints between the primary key and polymorphic_ctype, isn't it?

[jedie]

I demonstrate this with: jedie@adb038b

A test output looks like: https://travis-ci.org/django-polymorphic/django-polymorphic/jobs/623225731#L320-L338