selection-change-notification-on-selection-removed.html

<!DOCTYPE html>
<script src="../resources/testharness.js"></script>
<script src="../resources/testharnessreport.js"></script>
<script src="../resources/run-after-layout-and-paint.js"></script>

<div id="textbox" role="textbox" contenteditable>
  <p>
      One paragraph in an ARIA textbox.
    </p>
</div>

<script>
'use strict';

setup(() => {
  const textbox = document.getElementById('textbox');
  textbox.focus();
  const selectionRange = document.createRange();
  selectionRange.selectNodeContents(textbox);
  getSelection().removeAllRanges();
  getSelection().addRange(selectionRange);
});

async_test_after_layout_and_paint((t) => {
  const axRoot = accessibilityController.rootElement;

  axRoot.setNotificationListener(t.step_func((notification, intents) => {
    if (notification == 'DocumentSelectionChanged') {
      assert_array_equals(intents,
                          ['AXEventIntent(clearSelection,none,none,none)']);
      axRoot.unsetNotificationListener();
      assert_equals(axRoot.selectionAnchorObject, null, 'selectionAnchorObject');
      assert_equals(axRoot.selectionAnchorOffset, -1, 'selectionAnchorOffset');
      assert_equals(axRoot.selectionFocusObject, null, 'selectionFocusObject');
      assert_equals(axRoot.selectionFocusOffset, -1, 'selectionFocusOffset');
      t.done();
    }
  }));

  getSelection().removeAllRanges();
  });
  
</script>

chromium/third_party/blink/web_tests/accessibility/selection-change-notification-on-selection-removed.html