diff -r 5b6dd0d9171b -r d90f6237b3aa tests/test-rebase-collapse.t
--- a/tests/test-rebase-collapse.t	Tue May 04 10:16:34 2021 -0700
+++ b/tests/test-rebase-collapse.t	Tue May 04 10:49:32 2021 -0700
@@ -549,7 +549,7 @@
   o  0: f447d5abf5ea 'add'
   
   $ hg rebase --collapse -r 1 -d 0
-  abort: cannot rebase changeset with children
+  abort: cannot rebase changeset, as that will orphan 1 descendants
   (see 'hg help evolution.instability')
   [10]