def page_contains?(text_or_regexp)
      if text_or_regexp.class == String
        return page.has_content?(text_or_regexp)
      elsif text_or_regexp.class == Regexp
        return page.has_xpath?('.//*', :text => text_or_regexp)
      else
        raise ArgumentError, "Expected String or Regexp, got #{text_or_regexp.class}"
      end
    end
def page_contains?(text_or_regexp)
      if text_or_regexp.class == String
        return page.has_content?(text_or_regexp)
      elsif text_or_regexp.class == Regexp
        return page.has_xpath?('.//*', :text => text_or_regexp)
      else
        raise ArgumentError, "Expected String or Regexp, got #{text_or_regexp.class}"
      end
    end
Return `true` if the current page contains the given text or regular expression,
 or `false` if it does not.

 @param [String, Regexp] text_or_regexp
   Text or regular expression to look for

 @raise [ArgumentError]
   If the given argument isn't a String or Regexp

 @since 0.2.0