tor ran');
  }, `${description}Pre-flight check should succeed`);

  test_with_window((w) => {
    assert_rethrown(err => {
      define_and_create_element(w, class extends w.HTMLElement {
        constructor() { super(); throw err; }
      });
    });
  }, `${description}6.1.2. Errors in Construct(C) should be rethrown`);

  test_with_window((w) => {
    assert_throws(expectTypeError, () => {
      define_and_create_element(w, class {
        constructor() {}
      });
    });
  }, `${description}6.1.3. If