mercurial/util.py

--- a/mercurial/util.py	Wed Feb 21 22:47:47 2018 +0900
+++ b/mercurial/util.py	Sun Feb 25 22:06:53 2018 -0500
@@ -1188,7 +1188,7 @@
             return '0'
         if val is True:
             return '1'
-        return str(val)
+        return pycompat.bytestr(val)
     env = dict(encoding.environ)
     if environ:
         env.update((k, py2shell(v)) for k, v in environ.iteritems())