bpo-43916: Apply Py_TPFLAGS_DISALLOW_INSTANTIATION to selected types (GH-25748)

Apply Py_TPFLAGS_DISALLOW_INSTANTIATION to the following types:

* _dbm.dbm
* _gdbm.gdbm
* _multibytecodec.MultibyteCodec
* _sre..SRE_Scanner
* _thread._localdummy
* _thread.lock
* _winapi.Overlapped
* array.arrayiterator
* functools.KeyWrapper
* functools._lru_list_elem
* pyexpat.xmlparser
* re.Match
* re.Pattern
* unicodedata.UCD
* zlib.Compress
* zlib.Decompress

1 files changed, 8 insertions, 1 deletions

diff --git a/Lib/test/test_dbm_gnu.py b/Lib/test/test_dbm_gnu.py
index 017d0ff..b3e5572 100644
--- a/Lib/test/test_dbm_gnu.py
+++ b/Lib/test/test_dbm_gnu.py
@@ -1,5 +1,5 @@
 from test import support
-from test.support import import_helper
+from test.support import import_helper, cpython_only
 gdbm = import_helper.import_module("dbm.gnu") #skip if not supported
 import unittest
 import os
@@ -27,6 +27,13 @@ class TestGdbm(unittest.TestCase):
             self.g.close()
         unlink(filename)
 
+    @cpython_only
+    def test_disallow_instantiation(self):
+        # Ensure that the type disallows instantiation (bpo-43916)
+        self.g = gdbm.open(filename, 'c')
+        tp = type(self.g)
+        self.assertRaises(TypeError, tp)
+
     def test_key_methods(self):
         self.g = gdbm.open(filename, 'c')
         self.assertEqual(self.g.keys(), [])