bpo-34284: Proper tests for tuples of sys

VadimPushtaev · VadimPushtaev · commit d01857392e61 · 2018-09-03T16:53:43.000+03:00
diff --git a/Lib/test/test_sys.py b/Lib/test/test_sys.py
@@ -11,6 +11,7 @@
 import sysconfig
 import locale
 import threading
+import re
 
 # count the number of test runs, used to create unique
 # strings to intern in test_intern()
@@ -541,10 +542,26 @@ def assert_raise_on_new_sys_type(self, sys_attr):
         # Users are intentionally prevented from creating new instances of
         # sys.flags, sys.version_info, and sys.getwindowsversion.
         attr_type = type(sys_attr)
-        with self.assertRaises(TypeError):
+        attr_type_name = f'sys.{attr_type.__name__}'
+
+        cant_create_message = re.escape(f"cannot create '{attr_type_name}' instances")
+        object_message = re.escape(
+            f'object.__new__({attr_type_name}) is not safe, '
+            f'use {attr_type_name}.__new__()'
+        )
+        tuple_message = re.escape(
+            f'tuple.__new__({attr_type_name}) is not safe, '
+            f'use {attr_type_name}.__new__()'
+        )
+
+        with self.assertRaisesRegex(TypeError, cant_create_message):
             attr_type()
-        with self.assertRaises(TypeError):
+        with self.assertRaisesRegex(TypeError, cant_create_message):
             attr_type.__new__(attr_type)
+        with self.assertRaisesRegex(TypeError, object_message):
+            object.__new__(attr_type)
+        with self.assertRaisesRegex(TypeError, tuple_message):
+            tuple.__new__(attr_type)
 
     def test_sys_flags_no_instantiation(self):
         self.assert_raise_on_new_sys_type(sys.flags)
diff --git a/Lib/test/test_types.py b/Lib/test/test_types.py
@@ -1688,28 +1688,6 @@ def test_create_uncreatable(self):
         with self.assertRaisesRegex(TypeError, not_safe_message):
             object.__new__(C)
 
-    def test_create_sys_tuples(self):
-        C = type(sys.flags)
-
-        cant_create_message = re.escape("cannot create 'sys.flags' instances")
-        object_message = re.escape(
-            'object.__new__(sys.flags) is not safe, '
-            'use sys.flags.__new__()'
-        )
-        tuple_message = re.escape(
-            'tuple.__new__(sys.flags) is not safe, '
-            'use sys.flags.__new__()'
-        )
-
-        with self.assertRaisesRegex(TypeError, cant_create_message):
-            C()
-        with self.assertRaisesRegex(TypeError, cant_create_message):
-            C.__new__(C)
-        with self.assertRaisesRegex(TypeError, object_message):
-            object.__new__(C)
-        with self.assertRaisesRegex(TypeError, tuple_message):
-            tuple.__new__(C)
-
 
 if __name__ == '__main__':
     unittest.main()
