Actually delete the opening post when deleting the thread

boards/tests/test_post.py

@@ -37,9 +37,12 b' class PostTests(TestCase):'
         thread = opening_post.get_thread()
         reply = Post.objects.create_post("", "", thread=thread)
 
-        thread.delete()
+        opening_post.delete()
 
-        self.assertFalse(Post.objects.filter(id=reply.id).exists())
+        self.assertFalse(Post.objects.filter(id=reply.id).exists(),
+                         'Reply was not deleted with the thread.')
+        self.assertFalse(Post.objects.filter(id=opening_post.id).exists(),
+                         'Opening post was not deleted with the thread.')
 
     def test_post_to_thread(self):
         """Test adding post to a thread"""