diff -r 1e1c1bfb0be4 -r e2b87e19c6ef mercurial/pycompat.py
--- a/mercurial/pycompat.py	Sat Mar 03 10:39:48 2018 -0500
+++ b/mercurial/pycompat.py	Tue Feb 27 00:33:46 2018 +0530
@@ -192,11 +192,15 @@
 
     def strurl(url):
         """Converts a bytes url back to str"""
-        return url.decode(u'ascii')
+        if isinstance(url, bytes):
+            return url.decode(u'ascii')
+        return url
 
     def bytesurl(url):
         """Converts a str url to bytes by encoding in ascii"""
-        return url.encode(u'ascii')
+        if isinstance(url, str):
+            return url.encode(u'ascii')
+        return url
 
     def raisewithtb(exc, tb):
         """Raise exception with the given traceback"""