docs: def check_alert(self, text):
      """
      Assert an alert is showing with the given text.
      """
  
      try:
          alert = Alert(world.browser)
          if alert.text != text:
              raise AssertionError(
                  "Alert text expected to be {!r}, got {!r}.".format(
                      text, alert.text))
      except WebDriverException:
          # PhantomJS is kinda poor
          pass