--- a/mercurial/cmdutil.py	Tue Mar 07 12:52:00 2017 -0800
+++ b/mercurial/cmdutil.py	Thu Mar 02 03:52:36 2017 +0100
@@ -583,7 +583,7 @@
             raise error.CommandError(cmd, _('invalid arguments'))
         if not os.path.isfile(file_):
             raise error.Abort(_("revlog '%s' not found") % file_)
-        r = revlog.revlog(scmutil.opener(pycompat.getcwd(), audit=False),
+        r = revlog.revlog(scmutil.vfs(pycompat.getcwd(), audit=False),
                           file_[:-2] + ".i")
     return r