| <!DOCTYPE html> |
| <script src="../resources/testharness.js"></script> |
| <script src="../resources/testharness-helpers.js"></script> |
| <script src="../resources/testharnessreport.js"></script> |
| <script src="spec/resources/custom-elements-helpers.js"></script> |
| <body> |
| <script> |
| 'use strict'; |
| |
| test_with_window((w) => { |
| class X extends w.HTMLElement {} |
| |
| w.customElements.define('new-old', X); |
| assert_throws(null, () => { |
| w.document.registerElement('new-old', {prototype: X.prototype}); |
| }, '"registering" (v0) a name already "defined" should throw'); |
| |
| w.document.registerElement('old-new', { |
| prototype: Object.create(w.HTMLElement.prototype) |
| }); |
| class Y extends w.HTMLElement {} |
| assert_throws(null, () => { |
| w.customElements.define('old-new', Y); |
| }, '"defining" (v1) a name already "registered" (v0) should throw'); |
| }, 'Overlapping old and new-style custom elements are not allowed'); |
| </script> |
