acts_as_versioned and activerecord-diff problem

Hi,

I'm trying to use acts_as_versioned together with activerecord-diff plugin. I have a Testcase model which is versioned.

class Testcase < ActiveRecord::Base

  acts_as_versioned

  include ActiveRecord::Diff   diff :exclude => [:updated_at, :version, :id]   ... end

In my view, I'd like to show a summary of changes.

So I tried following code in the show.html.erb:

<%   last_version = nil   @testcase.versions.each do |version| %>   <li>     <%=version.created_at.to_s(:short)%>: <%       if last_version.nil?%>          Initially Created     <% else %>     <%       changes =       differences = version.diff(last_version)       differences.each do |field, d|         new_value, old_value = *d         changes << "#{field.to_s.humanize} changed " <<                    "from '#{old_value}' to '#{new_value}'"         end%>         <%=h changes.to_sentence%><%       end       last_version = version%>   </li> <%end%>

But when I try to enter the page, I got following error:

NoMethodError in Testcases#show

Showing /home/lukas/Aptana Studio 3 Workspace/testup/app/views/ testcases/show.html.erb where line #13 raised:

undefined method `diff' for #<Testcase::Version:0x7f49b65c5c90>

Extracted source (around line #13):

10: <% else %> 11: <% 12: changes = 13: differences = version.diff(last_version) 14: differences.each do |field, d| 15: #next if ignored_fields.include?(field) 16: new_value, old_value = *d

Seems that the activerecord-diff is not allowed for the versions of Testcase, only for testcase itself. But since the versions are managed automatically by acts_as_versioned, I do not know how to tell activerecord-diff to work with it.

Can you help me?

(The only solution I found so far is to manually create temporal Testcase from version object and use diff on that one, but there must be a better way)

Thanks in advance

Lukas Lipavsky