diff --git a/mercurial/context.py b/mercurial/context.py
--- a/mercurial/context.py
+++ b/mercurial/context.py
@@ -1892,9 +1892,9 @@ class memctx(committablectx):
             p2node = nullid
             p = pctx[f].parents() # if file isn't in pctx, check p2?
             if len(p) > 0:
-                p1node = p[0].node()
+                p1node = p[0].filenode()
                 if len(p) > 1:
-                    p2node = p[1].node()
+                    p2node = p[1].filenode()
             man[f] = revlog.hash(self[f].data(), p1node, p2node)
 
         for f in self._status.added: