--- a/tests/test-prune.t	Mon Feb 04 18:44:40 2013 +0100
+++ b/tests/test-prune.t	Mon Feb 04 22:04:50 2013 +0100
@@ -62,6 +62,18 @@
   4538525df7e2b9f09423636c61ef63a4cb872a2d 0 {'date': '*', 'user': 'test'} (glob)
   47d2a3944de8b013de3be9578e8e344ea2e6c097 0 {'date': '*', 'user': 'test'} (glob)
 
+cannot prune public changesets
+
+  $ hg prune 0
+  abort: cannot prune immutable changeset: 1f0dee641bb7
+  (see "hg help phases" for details)
+  [255]
+  $ hg debugobsolete
+  9d206ffc875e1bc304590549be293be36821e66c 0 {'date': '*', 'user': 'test'} (glob)
+  7c3bad9141dcb46ff89abf5f61856facd56e476c 0 {'date': '*', 'user': 'test'} (glob)
+  4538525df7e2b9f09423636c61ef63a4cb872a2d 0 {'date': '*', 'user': 'test'} (glob)
+  47d2a3944de8b013de3be9578e8e344ea2e6c097 0 {'date': '*', 'user': 'test'} (glob)
+
 Check successors addition
 ----------------------------