--- a/tests/test-topic-stack.t	Wed May 23 11:37:37 2018 +0200
+++ b/tests/test-topic-stack.t	Wed May 23 12:16:24 2018 +0200
@@ -64,6 +64,7 @@
   t1: c_a
   $ hg phase --public 'topic("other")'
   active topic 'other' is now empty
+  (use 'hg topic --clear' to clear it if needed)
 
 After changing the phase of all the changesets in "other" to public, the topic should still be active, but is empty. We should be better at informating the user about it and displaying good data in this case.