custom-elements/registries/CustomElementRegistry-define.html

<!DOCTYPE html>
<html>
<head>
<meta name="author" title="Ryosuke Niwa" href="mailto:rniwa@webkit.org">
<link rel="help" href="https://github.com/whatwg/html/issues/10854">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
</head>
<body>
<script>
test(() => {
    let registry = new CustomElementRegistry();
    assert_not_equals(registry, window.customElements);
}, 'Create a CustomElementRegistry not identically equal to window.customElements');

test(() => {
    let registry = new CustomElementRegistry();
    window.customElements.define('a-b', class extends HTMLElement {});
    assert_equals(registry.get('a-b'), undefined);
}, 'Defining an element in the global registry does not add a definition to a scoped CustomElementRegistry');

test(() => {
    let registry = new CustomElementRegistry();
    registry.define('b-c', class extends HTMLElement {});
    assert_equals(window.customElements.get('b-c'), undefined);
}, 'Defining an element in a scoped global registry does not add a definition to the global registry');

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