gh-139122: Honor subclass string conversion in UUID repr

Author: 1st1

Lib/test/test_uuid.py

@@ -303,6 +303,14 @@ def test_UUID_strip_braces(self):
                 with self.assertRaises(ValueError):
                     self.uuid.UUID(text)
 
+    def test_repr_subclass_str(self):
+        # repr() must call the subclass's __str__, as the Python version does.
+        class CustomUUID(self.uuid.UUID):
+            def __str__(self):
+                return 'custom uuid'
+
+        self.assertEqual(repr(CustomUUID(int=1)), "CustomUUID('custom uuid')")
+
     def test_exceptions(self):
         badvalue = lambda f: self.assertRaises(ValueError, f)
         badtype = lambda f: self.assertRaises(TypeError, f)

Modules/_uuidmodule.c

@@ -1487,20 +1487,13 @@ Uuid_str(PyObject *self)
 static PyObject *
 Uuid_repr(PyObject *self)
 {
-    PyObject *str_obj = Uuid_str(self);
-    if (str_obj == NULL) {
-        return NULL;
-    }
-
     // Get the class name (sadly can't use tp_name -- we don't need the full name)
     PyObject *cls_name = PyObject_GetAttrString((PyObject *)Py_TYPE(self), "__name__");
     if (cls_name == NULL) {
-        Py_DECREF(str_obj);
         return NULL;
     }
 
-    PyObject *repr = PyUnicode_FromFormat("%U('%U')", cls_name, str_obj);
-    Py_DECREF(str_obj);
+    PyObject *repr = PyUnicode_FromFormat("%U('%S')", cls_name, self);
     Py_DECREF(cls_name);
     return repr;
 }