From becb905f043c2b8a85b6ef099e82220988eae3fd 2022-08-17 08:33:36
From: Hugues Hoppe <hhoppe@users.noreply.github.com>
Date: 2022-08-17 08:33:36
Subject: [PATCH] Let %autoreload work on modules with frozen dataclasses

See Issue #12411 and Issue #12185.
The problem is that a frozen `dataclasses.dataclass` overrides the `__setattr__()` method, so updating its `__class__` member requires going through the base `object` class.  This seems to fix the problem.
---

diff --git a/IPython/extensions/autoreload.py b/IPython/extensions/autoreload.py
index 816d2f3..a0a8c27 100644
--- a/IPython/extensions/autoreload.py
+++ b/IPython/extensions/autoreload.py
@@ -300,7 +300,7 @@ def update_instances(old, new):
 
     for ref in refs:
         if type(ref) is old:
-            ref.__class__ = new
+            object.__setattr__(ref, "__class__", new)
 
 
 def update_class(old, new):