diff -r 9872526fc39f -r 7759d040d48d tests/test-topic-stack-data.t
--- a/tests/test-topic-stack-data.t	Fri Sep 15 23:25:38 2017 +0530
+++ b/tests/test-topic-stack-data.t	Sun Sep 17 19:59:25 2017 +0200
@@ -175,7 +175,7 @@
   $ hg topic --verbose
      bar (on branch: default, 5 changesets, 1 troubled, 2 heads)
      baz (on branch: default, 2 changesets, 2 behind)
-   * foo (on branch: lake, 2 changesets, ambiguous destination)
+   * foo (on branch: lake, 2 changesets, ambiguous destination: branch 'lake' has 2 heads)
      fuz (on branch: default, 3 changesets, 2 troubled, 1 behind)
 
 json
@@ -221,7 +221,7 @@
    },
    {
     "active": true,
-    "behinderror": "ambiguous destination",
+    "behinderror": "ambiguous destination: branch 'lake' has 2 heads",
     "branches+": "lake",
     "changesetcount": 2,
     "topic": "foo"
@@ -267,7 +267,7 @@
   t0^ add base_c (base)
   $ hg stack foo
   ### topic: foo
-  ### branch: lake, ambigious rebase destination
+  ### branch: lake, ambigious rebase destination - branch 'lake' has 2 heads
   t2@ add foo_b (current)
   t1: add foo_a
   t0^ add lake_a (base)