--- a/mercurial/context.py	Fri Jun 02 10:35:21 2017 +0530
+++ b/mercurial/context.py	Thu Jun 01 02:25:18 2017 +0530
@@ -1405,6 +1405,9 @@
     def __str__(self):
         return str(self._parents[0]) + r"+"
 
+    def __bytes__(self):
+        return bytes(self._parents[0]) + "+"
+
     def __nonzero__(self):
         return True