Merge pull request #2072 from ligthyear/fix-edit-body-too-similar-issue

Be more liberal when users wants to change their own body to a previous version

app/models/post.rb

@@ -101,12 +101,13 @@ class Post < ActiveRecord::Base
 
   def store_unique_post_key
     if SiteSetting.unique_posts_mins > 0
-      $redis.setex(unique_post_key, SiteSetting.unique_posts_mins.minutes.to_i, "1")
+      $redis.setex(unique_post_key, SiteSetting.unique_posts_mins.minutes.to_i, id)
     end
   end
 
   def matches_recent_post?
-    $redis.exists(unique_post_key)
+    post_id = $redis.get(unique_post_key)
+    post_id != nil and post_id != id
   end
 
   def raw_hash