state-failed-upgrade.html | Explore in Territory

<!DOCTYPE html>
<title>Custom Elements: Custom Element State "Failed" in Upgrades</title>
<script src="../../resources/testharness.js"></script>
<script src="../../resources/testharnessreport.js"></script>
<script src="resources/custom-elements-helpers.js"></script>
<body>
<script>
'use strict';

setup({
  allow_uncaught_exception: true,
});

// Custom Element State
// https://dom.spec.whatwg.org/#concept-element-custom-element-state

test_with_window(w => {
  let document = w.document;
  let element = document.createElement('a-a');
  let error = new Error('expected');

  let constructorCount = 0;
  w.customElements.define('a-a', class extends w.HTMLElement {
    constructor() {
      constructorCount++;
      throw error;
    }
    connectedCallback() {
      assert_unreached('connectedCallback should not be invoked if constructor threw');
    }
  });

  // Upgrade calls the constructor.
  // 9. If constructResult is an abrupt completion, then
  // Set element's custom element state to "failed".
  // https://html.spec.whatwg.org/multipage/scripting.html#upgrades
  let container = document.body;
  assert_reports_exactly(window, error, () => container.appendChild(element));
  assert_equals(constructorCount, 1, 'constructor should be invoked once');

  // "failed" is not "defined"
  // https://dom.spec.whatwg.org/#concept-element-defined
  assert_false(element.matches(':defined'));

  // "failed" element should implement HTMLUnknownElement only in "creating an element for a token"
  // https://html.spec.whatwg.org/#create-an-element-for-the-token
  assert_equals(Object.getPrototypeOf(element), w.HTMLElement.prototype);

  // 2. If element's custom element state is "failed", then abort these steps.
  // https://html.spec.whatwg.org/multipage/scripting.html#upgrades
  container.appendChild(element);
  assert_equals(constructorCount, 1, 'constructor should be invoked once');
});
</script>
</body>
chromium/third_party/blink/web_tests/custom-elements/spec/state-failed-upgrade.html
