gh-95196: Disable incorrect pickling of the C implemented classmethod descriptors (GH-96383)
(cherry picked from commit 77f0249308de76401bf4f3c6a057789c92f862d1)
Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>
diff --git a/Lib/test/pickletester.py b/Lib/test/pickletester.py
index 4e8d4e4..18d7f52 100644
--- a/Lib/test/pickletester.py
+++ b/Lib/test/pickletester.py
@@ -2773,6 +2773,15 @@ def pie(self):
unpickled = self.loads(self.dumps(method, proto))
self.assertEqual(method(obj), unpickled(obj))
+ descriptors = (
+ PyMethodsTest.__dict__['cheese'], # static method descriptor
+ PyMethodsTest.__dict__['wine'], # class method descriptor
+ )
+ for proto in range(pickle.HIGHEST_PROTOCOL + 1):
+ for descr in descriptors:
+ with self.subTest(proto=proto, descr=descr):
+ self.assertRaises(TypeError, self.dumps, descr, proto)
+
def test_c_methods(self):
global Subclass
class Subclass(tuple):
@@ -2808,6 +2817,15 @@ class Nested(str):
unpickled = self.loads(self.dumps(method, proto))
self.assertEqual(method(*args), unpickled(*args))
+ descriptors = (
+ bytearray.__dict__['maketrans'], # built-in static method descriptor
+ dict.__dict__['fromkeys'], # built-in class method descriptor
+ )
+ for proto in range(pickle.HIGHEST_PROTOCOL + 1):
+ for descr in descriptors:
+ with self.subTest(proto=proto, descr=descr):
+ self.assertRaises(TypeError, self.dumps, descr, proto)
+
def test_compat_pickle(self):
tests = [
(range(1, 7), '__builtin__', 'xrange'),
diff --git a/Misc/NEWS.d/next/Core and Builtins/2022-08-29-13-06-58.gh-issue-95196.eGRR4b.rst b/Misc/NEWS.d/next/Core and Builtins/2022-08-29-13-06-58.gh-issue-95196.eGRR4b.rst
new file mode 100644
index 0000000..37534fa
--- /dev/null
+++ b/Misc/NEWS.d/next/Core and Builtins/2022-08-29-13-06-58.gh-issue-95196.eGRR4b.rst
@@ -0,0 +1 @@
+Disable incorrect pickling of the C implemented classmethod descriptors.
diff --git a/Objects/descrobject.c b/Objects/descrobject.c
index 09b0f82..ee3ad1b 100644
--- a/Objects/descrobject.c
+++ b/Objects/descrobject.c
@@ -755,7 +755,7 @@ PyTypeObject PyClassMethodDescr_Type = {
0, /* tp_weaklistoffset */
0, /* tp_iter */
0, /* tp_iternext */
- descr_methods, /* tp_methods */
+ 0, /* tp_methods */
descr_members, /* tp_members */
method_getset, /* tp_getset */
0, /* tp_base */
