--- a/mercurial/localrepo.py	Wed Jul 15 11:38:54 2020 +0200
+++ b/mercurial/localrepo.py	Fri Jul 17 09:20:48 2020 +0200
@@ -412,13 +412,13 @@
 
     def changegroup(self, nodes, source):
         outgoing = discovery.outgoing(
-            self._repo, missingroots=nodes, missingheads=self._repo.heads()
+            self._repo, missingroots=nodes, ancestorsof=self._repo.heads()
         )
         return changegroup.makechangegroup(self._repo, outgoing, b'01', source)
 
     def changegroupsubset(self, bases, heads, source):
         outgoing = discovery.outgoing(
-            self._repo, missingroots=bases, missingheads=heads
+            self._repo, missingroots=bases, ancestorsof=heads
         )
         return changegroup.makechangegroup(self._repo, outgoing, b'01', source)