diff -r efbf7de09d2a -r afbfcc4e3473 mercurial/commandserver.py
--- a/mercurial/commandserver.py	Tue Oct 16 07:57:05 2018 +0200
+++ b/mercurial/commandserver.py	Tue Oct 16 07:57:40 2018 +0200
@@ -149,6 +149,8 @@
             raise StopIteration
         return l
 
+    __next__ = next
+
     def __getattr__(self, attr):
         if attr in (r'isatty', r'fileno', r'tell', r'seek'):
             raise AttributeError(attr)