'Upserts should include _cls information for inheritable classes'

def test_upsert_includes_cls(self):

    class Test(Document, ):
        test = StringField()
    Test.drop_collection()
    Test.objects(test='foo').update_one(upsert=True, set__test='foo')
    self.assertFalse(('_cls' in Test._collection.find_one()))
    class Test(Document, ):
        meta = {'allow_inheritance': True}
        test = StringField()
    Test.drop_collection()
    Test.objects(test='foo').update_one(upsert=True, set__test='foo')
    self.assertTrue(('_cls' in Test._collection.find_one()))
