--- a/mercurial/filelog.py	Tue May 10 14:42:53 2011 +0200
+++ b/mercurial/filelog.py	Tue May 10 17:38:58 2011 +0200
@@ -87,3 +87,6 @@
             return t2 != text
 
         return True
+
+    def _file(self, f):
+        return filelog(self.opener, f)