--- a/hgext/narrow/narrowdirstate.py	Sat Aug 04 23:15:06 2018 -0700
+++ b/hgext/narrow/narrowdirstate.py	Fri Aug 03 11:09:41 2018 -0700
@@ -11,7 +11,6 @@
 from mercurial import (
     error,
     match as matchmod,
-    narrowspec,
 )
 
 def wrapdirstate(repo, dirstate):
@@ -28,10 +27,6 @@
             return fn(self, *args)
         return _wrapper
 
-    def _narrowbackupname(backupname):
-        assert 'dirstate' in backupname
-        return backupname.replace('dirstate', narrowspec.FILENAME)
-
     class narrowdirstate(dirstate.__class__):
         def walk(self, match, subrepos, unknown, ignored, full=True,
                  narrowonly=True):
@@ -77,18 +72,5 @@
                 allfiles = [f for f in allfiles if repo.narrowmatch()(f)]
             super(narrowdirstate, self).rebuild(parent, allfiles, changedfiles)
 
-        def restorebackup(self, tr, backupname):
-            narrowspec.restorebackup(self._opener,
-                                     _narrowbackupname(backupname))
-            super(narrowdirstate, self).restorebackup(tr, backupname)
-
-        def savebackup(self, tr, backupname):
-            super(narrowdirstate, self).savebackup(tr, backupname)
-            narrowspec.savebackup(self._opener, _narrowbackupname(backupname))
-
-        def clearbackup(self, tr, backupname):
-            super(narrowdirstate, self).clearbackup(tr, backupname)
-            narrowspec.clearbackup(self._opener, _narrowbackupname(backupname))
-
     dirstate.__class__ = narrowdirstate
     return dirstate