--- a/tests/test-topic-debugcb.t	Fri Sep 01 18:46:10 2017 +0200
+++ b/tests/test-topic-debugcb.t	Fri Sep 01 17:15:55 2017 +0200
@@ -249,21 +249,26 @@
   o  [0:249055fcca50] root
   
 
-XXX: this should bot only put topic 'foo' on 3,4 but also 'bar' on 0,1,2
+XXX: this should  avoid create orphan changesets.
 
   $ hg debugconvertbookmark --all
+  changed topic to "bar" on 2 revisions
   switching to topic foo
   changed topic to "foo" on 2 revisions
 
   $ hg log -G
-  @  [7:b14d13efcfa7] E
+  @  [9:b14d13efcfa7] E
   |    topic: foo
-  o  [6:c89ca6e70978] D
+  o  [8:c89ca6e70978] D
   |    topic: foo
-  o  [3:ac05e0d05d00] C
-  |    bookmark: bar
-  o  [2:10f317d09e78] B
-  |
+  | o  [7:a3ea0dfe6a10] C
+  | |    topic: bar
+  | o  [6:db1bc6aab480] B
+  | |    topic: bar
+  x |  [3:ac05e0d05d00] C
+  | |
+  x |  [2:10f317d09e78] B
+  |/
   o  [1:e34122c9a2bf] A
   |
   o  [0:249055fcca50] root