tester.startPage(GuestBook.class);
tester.assertContains("Wicket Examples - guestbook");
// check if the list of comments is empty
tester.assertListView("comments", new ArrayList<Comment>());
tester.assertComponent("commentForm", Form.class);
FormTester formTester = tester.newFormTester("commentForm");
formTester.setValue("text", "test-1");
formTester.submit();