Issue #9212: Added the missing isdisjoint method to the dict_keys and
dict_items views.  The method is required by the collections.Set ABC,
which the views register as supporting.
diff --git a/Lib/test/test_dictviews.py b/Lib/test/test_dictviews.py
index 277e05b..4c04079 100644
--- a/Lib/test/test_dictviews.py
+++ b/Lib/test/test_dictviews.py
@@ -112,6 +112,24 @@
         self.assertEqual(d1.keys() ^ set(d3.keys()),
                          {'a', 'b', 'd', 'e'})
 
+        self.assertFalse(d1.keys().isdisjoint(d1.keys()))
+        self.assertFalse(d1.keys().isdisjoint(d2.keys()))
+        self.assertFalse(d1.keys().isdisjoint(list(d2.keys())))
+        self.assertFalse(d1.keys().isdisjoint(set(d2.keys())))
+        self.assertTrue(d1.keys().isdisjoint({'x', 'y', 'z'}))
+        self.assertTrue(d1.keys().isdisjoint(['x', 'y', 'z']))
+        self.assertTrue(d1.keys().isdisjoint(set(['x', 'y', 'z'])))
+        self.assertTrue(d1.keys().isdisjoint(set(['x', 'y'])))
+        self.assertTrue(d1.keys().isdisjoint(['x', 'y']))
+        self.assertTrue(d1.keys().isdisjoint({}))
+        self.assertTrue(d1.keys().isdisjoint(d3.keys()))
+
+        de = {}
+        self.assertTrue(de.keys().isdisjoint(set()))
+        self.assertTrue(de.keys().isdisjoint([]))
+        self.assertTrue(de.keys().isdisjoint(de.keys()))
+        self.assertTrue(de.keys().isdisjoint([1]))
+
     def test_items_set_operations(self):
         d1 = {'a': 1, 'b': 2}
         d2 = {'a': 2, 'b': 2}
@@ -144,6 +162,23 @@
         self.assertEqual(d1.items() ^ d3.items(),
                          {('a', 1), ('b', 2), ('d', 4), ('e', 5)})
 
+        self.assertFalse(d1.items().isdisjoint(d1.items()))
+        self.assertFalse(d1.items().isdisjoint(d2.items()))
+        self.assertFalse(d1.items().isdisjoint(list(d2.items())))
+        self.assertFalse(d1.items().isdisjoint(set(d2.items())))
+        self.assertTrue(d1.items().isdisjoint({'x', 'y', 'z'}))
+        self.assertTrue(d1.items().isdisjoint(['x', 'y', 'z']))
+        self.assertTrue(d1.items().isdisjoint(set(['x', 'y', 'z'])))
+        self.assertTrue(d1.items().isdisjoint(set(['x', 'y'])))
+        self.assertTrue(d1.items().isdisjoint({}))
+        self.assertTrue(d1.items().isdisjoint(d3.items()))
+
+        de = {}
+        self.assertTrue(de.items().isdisjoint(set()))
+        self.assertTrue(de.items().isdisjoint([]))
+        self.assertTrue(de.items().isdisjoint(de.items()))
+        self.assertTrue(de.items().isdisjoint([1]))
+
 
 def test_main():
     support.run_unittest(DictSetTest)