From: Raymond Hettinger <python@rcn.com>
Date: Tue, 14 Sep 2010 22:55:13 +0000 (+0000)
Subject: Future proof total_ordering against changes in methods defined on object.
X-Git-Tag: v3.2a3~261
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=1006bd459bc1cdd2aeb1762fadc6cc64d62c819f;p=python

Future proof total_ordering against changes in methods defined on object.
---

diff --git a/Lib/functools.py b/Lib/functools.py
index b39e77eb61..314c0dd906 100644
--- a/Lib/functools.py
+++ b/Lib/functools.py
@@ -82,7 +82,7 @@ def total_ordering(cls):
                    ('__lt__', lambda self, other: not self >= other)]
     }
     # Find comparisons not inherited from object.
-    roots = [op for op in convert if getattr(cls, op) is not getattr(object, op)]
+    roots = [op for op in convert if getattr(cls, op, None) is not getattr(object, op, None)]
     if not roots:
         raise ValueError('must define at least one ordering operation: < > <= >=')
     root = max(roots)       # prefer __lt__ to __le__ to __gt__ to __ge__