mercurial/httppeer.py

--- a/mercurial/httppeer.py	Fri Apr 13 21:06:50 2018 -0400
+++ b/mercurial/httppeer.py	Fri Apr 13 21:07:18 2018 -0400
@@ -278,6 +278,8 @@
         hgargssize = None
 
         for header, value in sorted(req.header_items()):
+            header = pycompat.bytesurl(header)
+            value = pycompat.bytesurl(value)
             if header.startswith('X-hgarg-'):
                 if hgargssize is None:
                     hgargssize = 0