FIX: You could update a topic to have a title that's too short if the TextCleaner

removed extra characters. Additionally, updating the title will not return an error
message to the client app if the operation fails (rather than failing silently.)

app/models/topic.rb

@@ -48,7 +48,7 @@ class Topic < ActiveRecord::Base
                                         :case_sensitive => false,
                                         :collection => Proc.new{ Topic.listable_topics } }
 
-  after_validation do
+  before_validation do
     self.title = TextCleaner.clean_title(TextSentinel.title_sentinel(title).text) if errors[:title].empty?
   end