Issue #21112: Fix regression in unittest.expectedFailure on subclasses.

Patch from Berker Peksag.

Lib/unittest/case.py

@@ -583,8 +583,11 @@ class TestCase(object):
             finally:
                 result.stopTest(self)
             return
-        expecting_failure = getattr(testMethod,
-                                    "__unittest_expecting_failure__", False)
+        expecting_failure_method = getattr(testMethod,
+                                           "__unittest_expecting_failure__", False)
+        expecting_failure_class = getattr(self,
+                                          "__unittest_expecting_failure__", False)
+        expecting_failure = expecting_failure_class or expecting_failure_method
         outcome = _Outcome(result)
         try:
             self._outcome = outcome

Lib/unittest/test/test_skipping.py

@@ -120,6 +120,39 @@ class Test_TestSkipping(unittest.TestCase):
         self.assertEqual(result.expectedFailures[0][0], test)
         self.assertTrue(result.wasSuccessful())
 
+    def test_expected_failure_with_wrapped_class(self):
+        @unittest.expectedFailure
+        class Foo(unittest.TestCase):
+            def test_1(self):
+                self.assertTrue(False)
+
+        events = []
+        result = LoggingResult(events)
+        test = Foo("test_1")
+        test.run(result)
+        self.assertEqual(events,
+                         ['startTest', 'addExpectedFailure', 'stopTest'])
+        self.assertEqual(result.expectedFailures[0][0], test)
+        self.assertTrue(result.wasSuccessful())
+
+    def test_expected_failure_with_wrapped_subclass(self):
+        class Foo(unittest.TestCase):
+            def test_1(self):
+                self.assertTrue(False)
+
+        @unittest.expectedFailure
+        class Bar(Foo):
+            pass
+
+        events = []
+        result = LoggingResult(events)
+        test = Bar("test_1")
+        test.run(result)
+        self.assertEqual(events,
+                         ['startTest', 'addExpectedFailure', 'stopTest'])
+        self.assertEqual(result.expectedFailures[0][0], test)
+        self.assertTrue(result.wasSuccessful())
+
     def test_expected_failure_subtests(self):
         # A failure in any subtest counts as the expected failure of the
         # whole test.

Misc/NEWS

@@ -14,6 +14,9 @@ Core and Builtins
 Library
 -------
 
+- Issue #21112: Fix regression in unittest.expectedFailure on subclasses.
+  Patch from Berker Peksag.
+
 - Issue #24764: cgi.FieldStorage.read_multi() now ignores the Content-Length
   header in part headers. Patch written by Peter Landry and reviewed by Pierre
   Quentel.