fixed comment vote functional test

app/helpers/post_votes_helper.rb

@@ -1,2 +1,14 @@
 module PostVotesHelper
+  def pool_version_diff(current)
+    prev = PoolVersion.where(["pool_id = ? and id < ?", current.pool_id, current.id]).order("id desc").first
+
+    if prev.nil?
+      return current.post_id_array.map {|x| content_tag("ins", "+#{x}")}.join(" ").html_safe
+    end
+
+    added = current.post_id_array - prev.post_id_array
+    removed = prev.post_id_array - current.post_id_array
+
+    added.map {|x| '<ins>+<a href="/posts/' + x + '">' + x + '</a></ins>'}.join(" ") + removed.map {|x| '<del>&ndash;<a href="/posts/' + x + '">' + x + '</a></del>'}.join(" ")
+  end
 end