VoiceOver on macOS does not announce fieldset description from aria-describedby when focussing inputs

Upstream bug: https://bugs.webkit.org/show_bug.cgi?id=185246 Date: 2018-05-03 Reported by: Oliver Byford Related to: https://github.com/alphagov/govuk-frontend/pull/681

Overview

TEST CASE:

Given the following HTML within a valid HTML5 document:

  <form>
    <fieldset aria-describedby="hint error">
      <legend>
        <h1>Have you changed your name?</h1>
      </legend>

      <span id="hint">This includes changing your last name or spelling your name differently.</span>
      <span id="error">Choose yes or no</span>

      <input name="changed_name" id="yes" type="radio" value="yes" >
      <label for="yes">Yes</label>

      <input name="changed_name" id="no" type="radio" value="no">
      <label for="no">No</label>

    </fieldset>
  </form>

EXPECTED BEHAVIOUR:

When focussing the first radio input ("Yes") in the fieldset, Voiceover should include the text content of any element(s) associated with the containing fieldset (using aria-describedby):

"Yes, radio button, 1 of 2, Have you changed your name? This includes changing your last name or spelling your name differently. Choose yes or no.

You are currently on a radio button, 1 of 2, inside of a group. To select this option press Control-Option-Space"

This is the behaviour currently exhibited by iOS 10/11, and would be consistent with other assistive technologies (as tested with JAWS 18, NVDA).

ACTUAL BEHAVIOUR:

When focussing the first radio input in a fieldset, Voiceover announces:

"Yes, radio button, 1 of 2, Have you changed your name?

You are currently on a radio button, 1 of 2, inside of a group. To select this option press Control-Option-Space"

As tested in Safari 11 and Safari Technology Preview 11.2 on macOS 10.13.4.

alphagov / reported-bugs