Ticket #17527: 17527.patch

django/db/models/fields/related.py

@@ -474 +474 @@
             def add(self, *objs):
                 for obj in objs:
                     if not isinstance(obj, self.model):
-                        raise TypeError("'%s' instance expected" % self.model._meta.object_name)
+                        raise TypeError("'%s' instance expected, got %r" % (self.model._meta.object_name, obj))
                     setattr(obj, rel_field.name, self.instance)
                     obj.save()
             add.alters_data = True