Fix OrderedDic.pop() to work for subclasses that define __missing__().

1 files changed, 15 insertions, 0 deletions

diff --git a/Lib/test/test_collections.py b/Lib/test/test_collections.py
index 8c95979..deda1cd 100644
--- a/Lib/test/test_collections.py
+++ b/Lib/test/test_collections.py
@@ -834,6 +834,10 @@ class TestOrderedDict(unittest.TestCase):
         self.assertEqual(list(d.items()),
             [('a', 1), ('b', 2), ('c', 3), ('d', 4), ('e', 5), ('f', 6), ('g', 7)])
 
+    def test_abc(self):
+        self.assertIsInstance(OrderedDict(), MutableMapping)
+        self.assertTrue(issubclass(OrderedDict, MutableMapping))
+
     def test_clear(self):
         pairs = [('c', 1), ('b', 2), ('a', 3), ('d', 4), ('e', 5), ('f', 6)]
         shuffle(pairs)
@@ -892,6 +896,17 @@ class TestOrderedDict(unittest.TestCase):
         self.assertEqual(len(od), 0)
         self.assertEqual(od.pop(k, 12345), 12345)
 
+        # make sure pop still works when __missing__ is defined
+        class Missing(OrderedDict):
+            def __missing__(self, key):
+                return 0
+        m = Missing(a=1)
+        self.assertEqual(m.pop('b', 5), 5)
+        self.assertEqual(m.pop('a', 6), 1)
+        self.assertEqual(m.pop('a', 6), 6)
+        with self.assertRaises(KeyError):
+            m.pop('a')
+
     def test_equality(self):
         pairs = [('c', 1), ('b', 2), ('a', 3), ('d', 4), ('e', 5), ('f', 6)]
         shuffle(pairs)