gistfile1.rb

last_response.body.should have_selector('h2') do |tag|
  tag.should match_selector('.disabled')
  tag.should contain('document is not well-formed')
end

# cucumber/rack-test output
      expected following output to contain a <.disabled/> tag:
      <h2 class="disabled">document is not well-formed</h2> (Spec::Expectations::ExpectationNotMetError)
      ./features/step_definitions/validation/validation_heading_steps.rb:8:in `__instance_exec0'
      ./features/step_definitions/validation/validation_heading_steps.rb:7:in `/^all headings except well formedness are visually disabled$/'
      features/validation_heading.feature:9:in `Then all headings except well formedness are visually disabled'