| <!DOCTYPE html> |
| <html> |
| <head> |
| <title>Custom Elements: HTML parser must construct a custom element instead of upgrading</title> |
| <meta name="author" title="Ryosuke Niwa" href="mailto:rniwa@webkit.org"> |
| <meta name="assert" content="HTML parser must construct a custom element instead of upgrading"> |
| <script src="/resources/testharness.js"></script> |
| <script src="/resources/testharnessreport.js"></script> |
| <link rel="help" href="https://html.spec.whatwg.org/#create-an-element-for-the-token"> |
| <link rel="help" href="https://dom.spec.whatwg.org/#concept-create-element"> |
| </head> |
| <body> |
| <div id="log"></div> |
| <script> |
| |
| let anotherElementCreatedBeforeSuperCall = undefined; |
| let elementCreatedBySuperCall = undefined; |
| let shouldCreateElementBeforeSuperCall = true; |
| class InstantiatesItselfBeforeSuper extends HTMLElement { |
| constructor() { |
| if (shouldCreateElementBeforeSuperCall) { |
| shouldCreateElementBeforeSuperCall = false; |
| anotherElementCreatedBeforeSuperCall = new InstantiatesItselfBeforeSuper(); |
| } |
| super(); |
| elementCreatedBySuperCall = this; |
| } |
| }; |
| customElements.define('instantiates-itself-before-super', InstantiatesItselfBeforeSuper); |
| |
| let shouldCreateAnotherInstance = true; |
| let anotherInstance = undefined; |
| let firstInstance = undefined; |
| class ReturnsAnotherInstance extends HTMLElement { |
| constructor() { |
| super(); |
| if (shouldCreateAnotherInstance) { |
| shouldCreateAnotherInstance = false; |
| firstInstance = this; |
| anotherInstance = new ReturnsAnotherInstance; |
| return anotherInstance; |
| } else |
| return this; |
| } |
| }; |
| customElements.define('returns-another-instance', ReturnsAnotherInstance); |
| |
| </script> |
| <instantiates-itself-before-super></instantiates-itself-before-super> |
| <returns-another-instance></returns-another-instance> |
| <script> |
| |
| test(function () { |
| var instance = document.querySelector('instantiates-itself-before-super'); |
| |
| assert_true(instance instanceof InstantiatesItselfBeforeSuper, 'HTML parser must insert the synchronously constructed custom element'); |
| assert_equals(instance, elementCreatedBySuperCall, 'HTML parser must insert the element returned by the custom element constructor'); |
| assert_not_equals(instance, anotherElementCreatedBeforeSuperCall, 'HTML parser must not insert another instance of the custom element created before super() call'); |
| assert_equals(anotherElementCreatedBeforeSuperCall.parentNode, null, 'HTML parser must not insert another instance of the custom element created before super() call'); |
| |
| }, 'HTML parser must use the returned value of the custom element constructor instead of the one created before super() call'); |
| |
| test(function () { |
| var instance = document.querySelector('returns-another-instance'); |
| |
| assert_true(instance instanceof ReturnsAnotherInstance, 'HTML parser must insert the synchronously constructed custom element'); |
| assert_equals(instance, anotherInstance, 'HTML parser must insert the element returned by the custom element constructor'); |
| assert_not_equals(instance, firstInstance, 'HTML parser must not insert the element created by super() call if the constructor returned another element'); |
| assert_equals(firstInstance.parentNode, null, 'HTML parser must not insert the element created by super() call if the constructor returned another element'); |
| |
| }, 'HTML parser must use the returned value of the custom element constructor instead using the one created in super() call'); |
| |
| </script> |
| </body> |
| </html> |
