bpo-36674: Honour the skipping decorators in TestCase.debug() (GH-28446)


unittest.TestCase.debug() raises now a SkipTest if the class or
the test method are decorated with the skipping decorator.

Previously it only raised a SkipTest if the test method was decorated
with other decorator in addition to the skipping decorator, or
if SkipTest was explicitly raised in the test or setup methods.
(cherry picked from commit dea59cf88adf5d20812edda330e085a4695baba4)

Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>
diff --git a/Lib/unittest/case.py b/Lib/unittest/case.py
index e8d9c05..b771ce0 100644
--- a/Lib/unittest/case.py
+++ b/Lib/unittest/case.py
@@ -651,8 +651,16 @@ def __call__(self, *args, **kwds):
 
     def debug(self):
         """Run the test without collecting errors in a TestResult"""
+        testMethod = getattr(self, self._testMethodName)
+        if (getattr(self.__class__, "__unittest_skip__", False) or
+            getattr(testMethod, "__unittest_skip__", False)):
+            # If the class or method was skipped.
+            skip_why = (getattr(self.__class__, '__unittest_skip_why__', '')
+                        or getattr(testMethod, '__unittest_skip_why__', ''))
+            raise SkipTest(skip_why)
+
         self.setUp()
-        getattr(self, self._testMethodName)()
+        testMethod()
         self.tearDown()
         while self._cleanups:
             function, args, kwargs = self._cleanups.pop(-1)
diff --git a/Lib/unittest/test/test_skipping.py b/Lib/unittest/test/test_skipping.py
index c14410a..7cb9d33 100644
--- a/Lib/unittest/test/test_skipping.py
+++ b/Lib/unittest/test/test_skipping.py
@@ -460,5 +460,71 @@ def test_1(self):
         self.assertIs(suite.run(result), result)
         self.assertEqual(result.skipped, [(test, "")])
 
+    def test_debug_skipping(self):
+        class Foo(unittest.TestCase):
+            def setUp(self):
+                events.append("setUp")
+            def tearDown(self):
+                events.append("tearDown")
+            def test1(self):
+                self.skipTest('skipping exception')
+                events.append("test1")
+            @unittest.skip("skipping decorator")
+            def test2(self):
+                events.append("test2")
+
+        events = []
+        test = Foo("test1")
+        with self.assertRaises(unittest.SkipTest) as cm:
+            test.debug()
+        self.assertIn("skipping exception", str(cm.exception))
+        self.assertEqual(events, ["setUp"])
+
+        events = []
+        test = Foo("test2")
+        with self.assertRaises(unittest.SkipTest) as cm:
+            test.debug()
+        self.assertIn("skipping decorator", str(cm.exception))
+        self.assertEqual(events, [])
+
+    def test_debug_skipping_class(self):
+        @unittest.skip("testing")
+        class Foo(unittest.TestCase):
+            def setUp(self):
+                events.append("setUp")
+            def tearDown(self):
+                events.append("tearDown")
+            def test(self):
+                events.append("test")
+
+        events = []
+        test = Foo("test")
+        with self.assertRaises(unittest.SkipTest) as cm:
+            test.debug()
+        self.assertIn("testing", str(cm.exception))
+        self.assertEqual(events, [])
+
+    def test_debug_skipping_subtests(self):
+        class Foo(unittest.TestCase):
+            def setUp(self):
+                events.append("setUp")
+            def tearDown(self):
+                events.append("tearDown")
+            def test(self):
+                with self.subTest(a=1):
+                    events.append('subtest')
+                    self.skipTest("skip subtest")
+                    events.append('end subtest')
+                events.append('end test')
+
+        events = []
+        result = LoggingResult(events)
+        test = Foo("test")
+        with self.assertRaises(unittest.SkipTest) as cm:
+            test.debug()
+        self.assertIn("skip subtest", str(cm.exception))
+        self.assertEqual(events, ['setUp', 'subtest'])
+
+
 if __name__ == "__main__":
     unittest.main()