1 files changed, 10 insertions, 0 deletions
diff --git a/Lib/test/test_unittest.py b/Lib/test/test_unittest.py
index b4716a4..954b40a 100644
--- a/Lib/test/test_unittest.py
+++ b/Lib/test/test_unittest.py
@@ -2096,6 +2096,16 @@ class Test_TestResult(TestCase):
                 'Tests getDescription() for a method with a longer '
                 'docstring.'))
 
+    def testStackFrameTrimming(self):
+        class Frame(object):
+            class tb_frame(object):
+                f_globals = {}
+        result = unittest.TestResult()
+        self.assertFalse(result._is_relevant_tb_level(Frame))
+
+        Frame.tb_frame.f_globals['__unittest'] = True
+        self.assertTrue(result._is_relevant_tb_level(Frame))
+
 classDict = dict(unittest.TestResult.__dict__)
 for m in ('addSkip', 'addExpectedFailure', 'addUnexpectedSuccess',
            '__init__'):