Reverted issue #24134 changes.

Lib/unittest/case.py

@@ -127,8 +127,6 @@ class _AssertRaisesContext(object):
                      (expected_regexp.pattern, str(exc_value)))
         return True
 
-def _sentinel(*args, **kwargs):
-    raise AssertionError('Should never be called')
 
 class TestCase(object):
     """A class whose instances are single test cases.
@@ -445,7 +443,7 @@ class TestCase(object):
             return  '%s : %s' % (safe_repr(standardMsg), safe_repr(msg))
 
 
-    def assertRaises(self, excClass, callableObj=_sentinel, *args, **kwargs):
+    def assertRaises(self, excClass, callableObj=None, *args, **kwargs):
         """Fail unless an exception of class excClass is raised
            by callableObj when invoked with arguments args and keyword
            arguments kwargs. If a different type of exception is
@@ -453,7 +451,7 @@ class TestCase(object):
            deemed to have suffered an error, exactly as for an
            unexpected exception.
 
-           If called with callableObj omitted, will return a
+           If called with callableObj omitted or None, will return a
            context object used like this::
 
                 with self.assertRaises(SomeException):
@@ -469,7 +467,7 @@ class TestCase(object):
                self.assertEqual(the_exception.error_code, 3)
         """
         context = _AssertRaisesContext(excClass, self)
-        if callableObj is _sentinel:
+        if callableObj is None:
             return context
         with context:
             callableObj(*args, **kwargs)
@@ -975,7 +973,7 @@ class TestCase(object):
             self.fail(self._formatMessage(msg, standardMsg))
 
     def assertRaisesRegexp(self, expected_exception, expected_regexp,
-                           callable_obj=_sentinel, *args, **kwargs):
+                           callable_obj=None, *args, **kwargs):
         """Asserts that the message in a raised exception matches a regexp.
 
         Args:
@@ -989,7 +987,7 @@ class TestCase(object):
         if expected_regexp is not None:
             expected_regexp = re.compile(expected_regexp)
         context = _AssertRaisesContext(expected_exception, self, expected_regexp)
-        if callable_obj is _sentinel:
+        if callable_obj is None:
             return context
         with context:
             callable_obj(*args, **kwargs)

Lib/unittest/test/test_case.py

@@ -967,9 +967,6 @@ test case
         # Failure when no exception is raised
         with self.assertRaises(self.failureException):
             self.assertRaises(ExceptionMock, lambda: 0)
-        # Failure when the function is None
-        with self.assertRaises(TypeError):
-            self.assertRaises(ExceptionMock, None)
         # Failure when another exception is raised
         with self.assertRaises(ExceptionMock):
             self.assertRaises(ValueError, Stub)
@@ -1008,8 +1005,6 @@ test case
         self.assertRaisesRegexp(ExceptionMock, re.compile('expect$'), Stub)
         self.assertRaisesRegexp(ExceptionMock, 'expect$', Stub)
         self.assertRaisesRegexp(ExceptionMock, u'expect$', Stub)
-        with self.assertRaises(TypeError):
-            self.assertRaisesRegexp(ExceptionMock, 'expect$', None)
 
     def testAssertNotRaisesRegexp(self):
         self.assertRaisesRegexp(

Misc/NEWS

@@ -13,6 +13,8 @@ Core and Builtins
 Library
 -------
 
+- Issue #24134: Reverted issue #24134 changes.
+
 
 What's New in Python 2.7.10 release candidate 1?
 ================================================