--- a/mercurial/context.py	Tue Jan 10 06:59:49 2017 +0800
+++ b/mercurial/context.py	Thu Jan 05 17:16:07 2017 +0000
@@ -1110,6 +1110,9 @@
         return filectx(self._repo, self._path, fileid=fileid,
                        filelog=self._filelog, changeid=changeid)
 
+    def rawdata(self):
+        return self._filelog.revision(self._filenode, raw=True)
+
     def data(self):
         try:
             return self._filelog.read(self._filenode)