--- a/mercurial/util.py	Wed Jan 13 21:52:26 2016 -0800
+++ b/mercurial/util.py	Thu Jan 14 09:31:01 2016 -0800
@@ -2655,7 +2655,7 @@
     def __enter__(self):
         return self
 
-    def __call__(self):
+    def enter(self):
         '''Create and enter context managers in the order in which they were
         passed to the constructor.'''
         values = []