added unit test for reduceByKeyAndWindow with invFunc=None

Author: dtolpin

python/pyspark/streaming/tests.py

@@ -582,6 +582,17 @@ def test_reduce_by_invalid_window(self):
         self.assertRaises(ValueError, lambda: d1.reduceByKeyAndWindow(None, None, 0.1, 0.1))
         self.assertRaises(ValueError, lambda: d1.reduceByKeyAndWindow(None, None, 1, 0.1))
 
+    def test_reduce_by_key_and_window_with_none_invFunc(self):
+        input = [range(1), range(2), range(3), range(4), range(5), range(6)]
+
+        def func(dstream):
+            return dstream.map(lambda x: (x, 1))\
+                .reduceByKeyAndWindow(operator.add, None, 5, 1)\
+                .filter(lambda kv: kv[1] > 0).count()
+
+        expected = [[2], [4], [6], [6], [6], [6]]
+        self._test_func(input, func, expected)
+
 
 class StreamingContextTests(PySparkStreamingTestCase):