diff -r f020a27b5391 Lib/test/test_abc.py
--- a/Lib/test/test_abc.py	Mon Oct 19 00:56:59 2015 +0300
+++ b/Lib/test/test_abc.py	Sun Oct 25 19:55:28 2015 -0700
@@ -389,6 +389,24 @@
         self.assertIsInstance(42, A)
         self.assertIsInstance(42, (A,))
 
+    def test_subclasshook(self):
+        class A(metaclass=abc.ABCMeta):
+            @classmethod
+            def __subclasshook__(cls, C):
+                if cls is A:
+                    return 'foo' in C.__dict__
+                return NotImplemented
+        self.assertFalse(issubclass(A, A))
+        self.assertFalse(issubclass(A, (A,)))
+        class B:
+            foo = 42
+        self.assertTrue(issubclass(B, A))
+        self.assertTrue(issubclass(B, (A,)))
+        class C:
+            spam = 42
+        self.assertFalse(issubclass(C, A))
+        self.assertFalse(issubclass(C, (A,)))
+
     def test_all_new_methods_are_called(self):
         class A(metaclass=abc.ABCMeta):
             pass