rspec users - Jan 2007 - Testing RJS select method

Hi

How can I test this kind of RJS code?

page.select ''#id .class''.each do |element|
  element.removeClassName(''whatever'')
end

I know that should_have_rjs admits a block, but i don''t know exactly
which is its purpose.
And I can test that the "select" part is beign called, but I
don''t
know hot to test the  "removeClassName" part.

Thanks in advance.