--- a/mercurial/revlog.py	Wed Jul 24 18:32:36 2019 +0530
+++ b/mercurial/revlog.py	Wed Aug 07 17:14:48 2019 +0200
@@ -1651,6 +1651,9 @@
         treated as raw data when applying flag transforms. 'raw' should be set
         to True when generating changegroups or in debug commands.
         """
+        return self._revisiondata(nodeorrev, _df, raw=raw)
+
+    def _revisiondata(self, nodeorrev, _df=None, raw=False):
         if isinstance(nodeorrev, int):
             rev = nodeorrev
             node = self.node(rev)