revert a37cc3d926ec (#5322)

Lib/test/test_descr.py

@@ -3,7 +3,6 @@ import gc
 import sys
 import types
 import unittest
-import warnings
 import weakref
 
 from copy import deepcopy
@@ -1551,84 +1550,6 @@ order (MRO) for bases """
         self.assertEqual(b.foo, 3)
         self.assertEqual(b.__class__, D)
 
-    def test_bad_new(self):
-        self.assertRaises(TypeError, object.__new__)
-        self.assertRaises(TypeError, object.__new__, '')
-        self.assertRaises(TypeError, list.__new__, object)
-        self.assertRaises(TypeError, object.__new__, list)
-        class C(object):
-            __new__ = list.__new__
-        self.assertRaises(TypeError, C)
-        class C(list):
-            __new__ = object.__new__
-        self.assertRaises(TypeError, C)
-
-    def test_object_new(self):
-        class A(object):
-            pass
-        object.__new__(A)
-        self.assertRaises(TypeError, object.__new__, A, 5)
-        object.__init__(A())
-        self.assertRaises(TypeError, object.__init__, A(), 5)
-
-        class A(object):
-            def __init__(self, foo):
-                self.foo = foo
-        object.__new__(A)
-        object.__new__(A, 5)
-        object.__init__(A(3))
-        self.assertRaises(TypeError, object.__init__, A(3), 5)
-
-        class A(object):
-            def __new__(cls, foo):
-                return object.__new__(cls)
-        object.__new__(A)
-        self.assertRaises(TypeError, object.__new__, A, 5)
-        object.__init__(A(3))
-        object.__init__(A(3), 5)
-
-        class A(object):
-            def __new__(cls, foo):
-                return object.__new__(cls)
-            def __init__(self, foo):
-                self.foo = foo
-        object.__new__(A)
-        with warnings.catch_warnings(record=True) as w:
-            warnings.simplefilter('always', DeprecationWarning)
-            a = object.__new__(A, 5)
-        self.assertEqual(type(a), A)
-        self.assertEqual(len(w), 1)
-        object.__init__(A(3))
-        a = A(3)
-        with warnings.catch_warnings(record=True) as w:
-            warnings.simplefilter('always', DeprecationWarning)
-            object.__init__(a, 5)
-        self.assertEqual(a.foo, 3)
-        self.assertEqual(len(w), 1)
-
-    def test_restored_object_new(self):
-        class A(object):
-            def __new__(cls, *args, **kwargs):
-                raise AssertionError
-        self.assertRaises(AssertionError, A)
-        class B(A):
-            __new__ = object.__new__
-            def __init__(self, foo):
-                self.foo = foo
-        with warnings.catch_warnings():
-            warnings.simplefilter('error', DeprecationWarning)
-            b = B(3)
-        self.assertEqual(b.foo, 3)
-        self.assertEqual(b.__class__, B)
-        del B.__new__
-        self.assertRaises(AssertionError, B)
-        del A.__new__
-        with warnings.catch_warnings():
-            warnings.simplefilter('error', DeprecationWarning)
-            b = B(3)
-        self.assertEqual(b.foo, 3)
-        self.assertEqual(b.__class__, B)
-
     def test_altmro(self):
         # Testing mro() and overriding it...
         class A(object):
@@ -3835,24 +3756,6 @@ order (MRO) for bases """
         self.assertEqual(isinstance(d, D), True)
         self.assertEqual(d.foo, 1)
 
-        class C(object):
-            @staticmethod
-            def __new__(*args):
-                return args
-        self.assertEqual(C(1, 2), (C, 1, 2))
-        class D(C):
-            pass
-        self.assertEqual(D(1, 2), (D, 1, 2))
-
-        class C(object):
-            @classmethod
-            def __new__(*args):
-                return args
-        self.assertEqual(C(1, 2), (C, C, 1, 2))
-        class D(C):
-            pass
-        self.assertEqual(D(1, 2), (D, D, 1, 2))
-
     def test_imul_bug(self):
         # Testing for __imul__ problems...
         # SF bug 544647

Misc/NEWS

@@ -2,6 +2,17 @@
 Python News
 +++++++++++
 
+What's New in Python 2.7.13
+===========================
+
+*Release date: 2016-12-XX*
+
+Core and Builtins
+-----------------
+
+- Revert a37cc3d926ec (Issue #5322).
+
+
 What's New in Python 2.7.13 release candidate 1?
 ================================================
 
@@ -10,9 +21,6 @@ What's New in Python 2.7.13 release candidate 1?
 Core and Builtins
 -----------------
 
-- Issue #5322: Fixed setting __new__ to a PyCFunction inside Python code.
-  Original patch by Andreas Stührk.
-
 - Issue #28847: dumbdbm no longer writes the index file in when it is not
   changed and supports reading read-only files.
 

Objects/typeobject.c

@@ -6304,33 +6304,7 @@ update_one_slot(PyTypeObject *type, slotdef *p)
                sanity checks and constructing a new argument
                list.  Cut all that nonsense short -- this speeds
                up instance creation tremendously. */
-            PyObject *self = PyCFunction_GET_SELF(descr);
-            if (!self || !PyType_Check(self)) {
-                /* This should never happen because
-                   tp_new_wrapper expects a type for self.
-                   Use slot_tp_new which will call
-                   tp_new_wrapper which will raise an
-                   exception. */
-                specific = (void *)slot_tp_new;
-            }
-            else {
-                specific = ((PyTypeObject *)self)->tp_new;
-                /* Check that the user does not do anything
-                   silly and unsafe like object.__new__(dict).
-                   To do this, we check that the most derived
-                   base that's not a heap type is this type. */
-                PyTypeObject *staticbase = type->tp_base;
-                while (staticbase &&
-                       (staticbase->tp_flags & Py_TPFLAGS_HEAPTYPE))
-                    staticbase = staticbase->tp_base;
-                if (staticbase &&
-                    staticbase->tp_new != specific)
-                    /* Seems to be unsafe, better use
-                       slot_tp_new which will call
-                       tp_new_wrapper which will raise an
-                       exception if it is unsafe. */
-                    specific = (void *)slot_tp_new;
-            }
+            specific = (void *)type->tp_new;
             /* XXX I'm not 100% sure that there isn't a hole
                in this reasoning that requires additional
                sanity checks.  I'll buy the first person to