Comment out some tests that won't pass now that we've reverted the

picklability regression.  Also, as per further discussion, remove the
regressing code.

Lib/test/test_csv.py

@@ -426,16 +426,17 @@ class TestDialectRegistry(unittest.TestCase):
         self.assertRaises(TypeError, csv.reader, [], quoting = -1)
         self.assertRaises(TypeError, csv.reader, [], quoting = 100)
 
-    def test_copy(self):
-        for name in csv.list_dialects():
-            dialect = csv.get_dialect(name)
-            self.assertRaises(TypeError, copy.copy, dialect)
-
-    def test_pickle(self):
-        for name in csv.list_dialects():
-            dialect = csv.get_dialect(name)
-            for proto in range(pickle.HIGHEST_PROTOCOL + 1):
-                self.assertRaises(TypeError, pickle.dumps, dialect, proto)
+    # See issue #22995
+    ## def test_copy(self):
+    ##     for name in csv.list_dialects():
+    ##         dialect = csv.get_dialect(name)
+    ##         self.assertRaises(TypeError, copy.copy, dialect)
+
+    ## def test_pickle(self):
+    ##     for name in csv.list_dialects():
+    ##         dialect = csv.get_dialect(name)
+    ##         for proto in range(pickle.HIGHEST_PROTOCOL + 1):
+    ##             self.assertRaises(TypeError, pickle.dumps, dialect, proto)
 
 class TestCsvBase(unittest.TestCase):
     def readerAssertEqual(self, input, expected_result):

Objects/typeobject.c

@@ -3866,33 +3866,6 @@ _PyObject_GetState(PyObject *obj, int required)
         }
 
         assert(slotnames == Py_None || PyList_Check(slotnames));
-#if 0
-        /* 2016-01-11 barry - This clause breaks at least three packages which
-           rely on Cython: kivy, pysam, and s3ql.  Cython may be doing
-           something funny under the hood, but as this is clearly a regression
-           and the rationale for this prohibition is suspect, I am commenting
-           this out.  Perhaps it should just be removed.  See issue #22995 for
-           details.
-        */
-        if (required) {
-            Py_ssize_t basicsize = PyBaseObject_Type.tp_basicsize;
-            if (obj->ob_type->tp_dictoffset)
-                basicsize += sizeof(PyObject *);
-            if (obj->ob_type->tp_weaklistoffset)
-                basicsize += sizeof(PyObject *);
-            if (slotnames != Py_None)
-                basicsize += sizeof(PyObject *) * Py_SIZE(slotnames);
-            if (obj->ob_type->tp_basicsize > basicsize) {
-                Py_DECREF(slotnames);
-                Py_DECREF(state);
-                PyErr_Format(PyExc_TypeError,
-                             "can't pickle %.200s objects",
-                             Py_TYPE(obj)->tp_name);
-                return NULL;
-            }
-        }
-#endif
-
         if (slotnames != Py_None && Py_SIZE(slotnames) > 0) {
             PyObject *slots;
             Py_ssize_t slotnames_size, i;