--- a/mercurial/extensions.py	Tue Sep 05 13:37:36 2017 -0700
+++ b/mercurial/extensions.py	Tue Sep 05 15:18:45 2017 -0700
@@ -377,7 +377,8 @@
             break
 
     origfn = entry[0]
-    wrap = bind(util.checksignature(wrapper), util.checksignature(origfn))
+    wrap = functools.partial(util.checksignature(wrapper),
+                             util.checksignature(origfn))
     _updatewrapper(wrap, origfn, wrapper)
     if docstring is not None:
         wrap.__doc__ += docstring