fixing bug caused by batch objects on querysets being copied

cqlengine/query.py

@@ -227,6 +227,12 @@ class QuerySet(object):
         for k,v in self.__dict__.items():
             if k in ['_con', '_cur', '_result_cache', '_result_idx']:
                 clone.__dict__[k] = None
+            elif k == '_batch':
+                # we need to keep the same batch instance across
+                # all queryset clones, otherwise the batched queries
+                # fly off into other batch instances which are never
+                # executed, thx @dokai
+                clone.__dict__[k] = self._batch
             else:
                 clone.__dict__[k] = copy.deepcopy(v, memo)
 

cqlengine/tests/test_batch_query.py

@@ -31,8 +31,6 @@ class BatchQueryTests(BaseCassEngTestCase):
         for obj in TestMultiKeyModel.filter(partition=self.pkey):
             obj.delete()
 
-
-
     def test_insert_success_case(self):
 
         b = BatchQuery()
@@ -90,4 +88,18 @@ class BatchQueryTests(BaseCassEngTestCase):
         for i in range(5):
             TestMultiKeyModel.get(partition=self.pkey, cluster=i)
 
+    def test_bulk_delete_success_case(self):
+
+        for i in range(1):
+            for j in range(5):
+                TestMultiKeyModel.create(partition=i, cluster=j, count=i*j, text='{}:{}'.format(i,j))
+
+        with BatchQuery() as b:
+            TestMultiKeyModel.objects.batch(b).filter(partition=0).delete()
+            assert TestMultiKeyModel.filter(partition=0).count() == 5
+
+        assert TestMultiKeyModel.filter(partition=0).count() == 0
+        #cleanup
+        for m in TestMultiKeyModel.all():
+            m.delete()