diff --git a/mercurial/obsolete.py b/mercurial/obsolete.py
index cf414981978a53d2d9a38bbb971bddd3c9a2ba14_bWVyY3VyaWFsL29ic29sZXRlLnB5..2e6f03a193f9603dfa0b9cb841a2628745955f6f_bWVyY3VyaWFsL29ic29sZXRlLnB5 100644
--- a/mercurial/obsolete.py
+++ b/mercurial/obsolete.py
@@ -241,6 +241,10 @@
         """List of successor changesets node identifiers"""
         return self._data[1]
 
+    def parentnodes(self):
+        """Parents of the precursors (None if not recorded)"""
+        return self._data[5]
+
     def metadata(self):
         """Decoded metadata dictionary"""
         if self._decodedmeta is None: