Make sure the list.sort's decorate step unwinds itself before returning

an exception raised by the key function.
(Suggested by Michael Hudson.)

1 files changed, 7 insertions, 0 deletions

diff --git a/Lib/test/test_sort.py b/Lib/test/test_sort.py
index 053b3381d5..2659a9088d 100644
--- a/Lib/test/test_sort.py
+++ b/Lib/test/test_sort.py
@@ -186,6 +186,13 @@ class TestDecorateSortUndecorate(unittest.TestCase):
         data = 'The quick Brown fox Jumped over The lazy Dog'.split()
         self.assertRaises(TypeError, data.sort, "bad", str.lower)
 
+    def test_key_with_exception(self):
+        # Verify that the wrapper has been removed
+        data = range(-2,2)
+        dup = data[:]
+        self.assertRaises(ZeroDivisionError, data.sort, None, lambda x: 1/x)
+        self.assertEqual(data, dup)
+
     def test_reverse(self):
         data = range(100)
         random.shuffle(data)