bpo-46903: Handle str-subclasses in virtual instance dictionaries. (GH-31658)

1 files changed, 24 insertions, 0 deletions

diff --git a/Lib/test/test_unicode.py b/Lib/test/test_unicode.py
index 8e4e648..e97f971 100644
--- a/Lib/test/test_unicode.py
+++ b/Lib/test/test_unicode.py
@@ -3044,6 +3044,30 @@ class StringModuleTest(unittest.TestCase):
             ]])
         self.assertRaises(TypeError, _string.formatter_field_name_split, 1)
 
+    def test_str_subclass_attr(self):
+
+        name = StrSubclass("name")
+        name2 = StrSubclass("name2")
+        class Bag:
+            pass
+
+        o = Bag()
+        with self.assertRaises(AttributeError):
+            delattr(o, name)
+        setattr(o, name, 1)
+        self.assertEquals(o.name, 1)
+        o.name = 2
+        self.assertEquals(list(o.__dict__), [name])
+
+        with self.assertRaises(AttributeError):
+            delattr(o, name2)
+        with self.assertRaises(AttributeError):
+            del o.name2
+        setattr(o, name2, 3)
+        self.assertEquals(o.name2, 3)
+        o.name2 = 4
+        self.assertEquals(list(o.__dict__), [name, name2])
+
 
 if __name__ == "__main__":
     unittest.main()