LayoutTests/accessibility/custom-elements/heading.html

<!DOCTYPE html>
<html>
<body>
<script src="../../resources/js-test.js"></script>
<script src="../../resources/accessibility-helper.js"></script>
<custom-heading id="heading-1">1. Some title</custom-heading>
<custom-heading id="heading-1-1" aria-level="2">1.1. Subtitle</custom-heading>
<script>

customElements.define('custom-heading', class CustomElement extends HTMLElement {
    constructor()
    {
        super();
        const internals = this.attachInternals();
        internals.role = 'heading';
        internals.ariaLevel = '1';
    }
});

description("This tests that aria fallback roles work correctly.");
if (!window.accessibilityController)
    debug('This test requires accessibilityController');
else {
    shouldBe('accessibilityController.accessibleElementById("heading-1").intValue', '1');
    shouldBe('accessibilityController.accessibleElementById("heading-1-1").intValue', '2');
}

</script>
</body>
</html>