- Issue #18622: unittest.mock.mock_open().reset_mock would recurse infinitely.

Patch from Nicola Palumbo and Laurent De Buyst.

Lib/unittest/test/testmock/testmock.py

@@ -246,6 +246,9 @@ def test_reset_mock_recursion(self):
         # used to cause recursion
         mock.reset_mock()
 
+    def test_reset_mock_on_mock_open_issue_18622(self):
+        a = mock.mock_open()
+        a.reset_mock()
 
     def test_call(self):
         mock = Mock()