diff -r f99d64e8a4e4 -r f0b6fbea00cf mercurial/subrepoutil.py
--- a/mercurial/subrepoutil.py	Thu Mar 22 21:19:31 2018 +0900
+++ b/mercurial/subrepoutil.py	Thu Mar 22 21:56:20 2018 +0900
@@ -21,6 +21,9 @@
     phases,
     util,
 )
+from .utils import (
+    stringutil,
+)
 
 nullstate = ('', '', 'empty')
 
@@ -74,7 +77,7 @@
         for pattern, repl in p.items('subpaths'):
             # Turn r'C:\foo\bar' into r'C:\\foo\\bar' since re.sub
             # does a string decode.
-            repl = util.escapestr(repl)
+            repl = stringutil.escapestr(repl)
             # However, we still want to allow back references to go
             # through unharmed, so we turn r'\\1' into r'\1'. Again,
             # extra escapes are needed because re.sub string decodes.