RustPython
diff --git a/Lib/test/test_copyreg.py b/Lib/test/test_copyreg.py
@@ -0,0 +1,128 @@
+import copyreg
+import unittest
+
+from test.pickletester import ExtensionSaver
+
+class C:
+    pass
+
+def pickle_C(c):
+    return C, ()
+
+
+class WithoutSlots(object):
+    pass
+
+class WithWeakref(object):
+    __slots__ = ('__weakref__',)
+
+class WithPrivate(object):
+    __slots__ = ('__spam',)
+
+class _WithLeadingUnderscoreAndPrivate(object):
+    __slots__ = ('__spam',)
+
+class ___(object):
+    __slots__ = ('__spam',)
+
+class WithSingleString(object):
+    __slots__ = 'spam'
+
+class WithInherited(WithSingleString):
+    __slots__ = ('eggs',)
+
+
+class CopyRegTestCase(unittest.TestCase):
+
+    def test_class(self):
+        copyreg.pickle(C, pickle_C)
+
+    def test_noncallable_reduce(self):
+        self.assertRaises(TypeError, copyreg.pickle,
+                          C, "not a callable")
+
+    def test_noncallable_constructor(self):
+        self.assertRaises(TypeError, copyreg.pickle,
+                          C, pickle_C, "not a callable")
+
+    def test_bool(self):
+        import copy
+        self.assertEqual(True, copy.copy(True))
+
+    def test_extension_registry(self):
+        mod, func, code = 'junk1 ', ' junk2', 0xabcd
+        e = ExtensionSaver(code)
+        try:
+            # Shouldn't be in registry now.
+            self.assertRaises(ValueError, copyreg.remove_extension,
+                              mod, func, code)
+            copyreg.add_extension(mod, func, code)
+            # Should be in the registry.
+            self.assertTrue(copyreg._extension_registry[mod, func] == code)
+            self.assertTrue(copyreg._inverted_registry[code] == (mod, func))
+            # Shouldn't be in the cache.
+            self.assertNotIn(code, copyreg._extension_cache)
+            # Redundant registration should be OK.
+            copyreg.add_extension(mod, func, code)  # shouldn't blow up
+            # Conflicting code.
+            self.assertRaises(ValueError, copyreg.add_extension,
+                              mod, func, code + 1)
+            self.assertRaises(ValueError, copyreg.remove_extension,
+                              mod, func, code + 1)
+            # Conflicting module name.
+            self.assertRaises(ValueError, copyreg.add_extension,
+                              mod[1:], func, code )
+            self.assertRaises(ValueError, copyreg.remove_extension,
+                              mod[1:], func, code )
+            # Conflicting function name.
+            self.assertRaises(ValueError, copyreg.add_extension,
+                              mod, func[1:], code)
+            self.assertRaises(ValueError, copyreg.remove_extension,
+                              mod, func[1:], code)
+            # Can't remove one that isn't registered at all.
+            if code + 1 not in copyreg._inverted_registry:
+                self.assertRaises(ValueError, copyreg.remove_extension,
+                                  mod[1:], func[1:], code + 1)
+
+        finally:
+            e.restore()
+
+        # Shouldn't be there anymore.
+        self.assertNotIn((mod, func), copyreg._extension_registry)
+        # The code *may* be in copyreg._extension_registry, though, if
+        # we happened to pick on a registered code.  So don't check for
+        # that.
+
+        # Check valid codes at the limits.
+        for code in 1, 0x7fffffff:
+            e = ExtensionSaver(code)
+            try:
+                copyreg.add_extension(mod, func, code)
+                copyreg.remove_extension(mod, func, code)
+            finally:
+                e.restore()
+
+        # Ensure invalid codes blow up.
+        for code in -1, 0, 0x80000000:
+            self.assertRaises(ValueError, copyreg.add_extension,
+                              mod, func, code)
+
+    def test_slotnames(self):
+        self.assertEqual(copyreg._slotnames(WithoutSlots), [])
+        self.assertEqual(copyreg._slotnames(WithWeakref), [])
+        expected = ['_WithPrivate__spam']
+        self.assertEqual(copyreg._slotnames(WithPrivate), expected)
+        expected = ['_WithLeadingUnderscoreAndPrivate__spam']
+        self.assertEqual(copyreg._slotnames(_WithLeadingUnderscoreAndPrivate),
+                         expected)
+        self.assertEqual(copyreg._slotnames(___), ['__spam'])
+        self.assertEqual(copyreg._slotnames(WithSingleString), ['spam'])
+        expected = ['eggs', 'spam']
+        expected.sort()
+        result = copyreg._slotnames(WithInherited)
+        result.sort()
+        self.assertEqual(result, expected)
+
+
+if __name__ == "__main__":
+    unittest.main()