[bug 697445] Fix kbforums async preview.

* And add a test for it.

apps/kbforums/templates/kbforums/includes/post.html

@@ -17,7 +17,7 @@
       <img src="{{ MEDIA_URL }}img/forums/delete.png" alt="{{ _('Delete') }}" title="{{ _('Delete') }}">
     </a>
   {% endif %}
-  {% if document.slug and post.id %}
+  {% if document and document.slug and post.id %}
     <form class="report" action="{{ url('wiki.discuss.flag_post', document.slug, post.id) }}" method="post">
      {% include 'wiki/includes/flag_form.html' %}
     </form>

apps/kbforums/tests/test_templates.py

@@ -110,6 +110,17 @@ def test_preview_reply(self):
         eq_(content, doc('#post-preview div.content').text())
         eq_(num_posts, t.post_set.count())
 
+    def test_preview_async(self):
+        """Preview a reply."""
+        self.client.login(username='rrosario', password='testpass')
+        d = Document.objects.all()[0]
+        content = 'Full of awesome.'
+        response = post(self.client, 'wiki.discuss.post_preview_async',
+                        {'content': content}, args=[d.slug])
+        eq_(200, response.status_code)
+        doc = pq(response.content)
+        eq_(content, doc('div.content').text())
+
     def test_watch_thread(self):
         """Watch and unwatch a thread."""
         self.client.login(username='rrosario', password='testpass')