mercurial/templatekw.py

--- a/mercurial/templatekw.py	Tue Feb 27 14:28:17 2018 +0530
+++ b/mercurial/templatekw.py	Tue Feb 27 14:41:24 2018 +0530
@@ -791,7 +791,7 @@
 
         data.append({'successors': successors, 'markers': finalmarkers})
 
-    f = _showlist('succsandmarkers', data, args)
+    f = _showlist('succsandmarkers', data, pycompat.byteskwargs(args))
     return _hybrid(f, data, lambda x: x, pycompat.identity)
 
 @templatekeyword('p1rev')