--- a/mercurial/context.py	Mon Mar 29 01:35:54 2021 +0200
+++ b/mercurial/context.py	Tue Mar 30 02:33:12 2021 +0200
@@ -3000,7 +3000,7 @@
             parents = [repo[p] for p in parents if p is not None]
         parents = parents[:]
         while len(parents) < 2:
-            parents.append(repo[nullid])
+            parents.append(repo[nullrev])
         p1, p2 = self._parents = parents
 
         # sanity check to ensure that the reused manifest parents are