def assert_contain(content)
      hc = HasContent.new(content)
      assert hc.matches?(current_dom), hc.failure_message
    end
def assert_contain(content)
      hc = HasContent.new(content)
      assert hc.matches?(current_dom), hc.failure_message
    end
Asserts that the body of the response contain
 the supplied string or regexp