du1.isConnected, 'el#du1 still connected after reassign');
      test(du1.children.length === 1, 'el#du1 has only one child after reset');
      test(
        du1.children[0].innerText === 'TEST',
        'new user.name span has updated text'
      );

      delete data.user;
      test(!du1.isConnected, 'el#du1 disconnected after user delete');
    </script>

    <div id="d1">
      <div-user sb-mark="users.#">
        <span slot="name" sb-mark="users.#.name"></span>
        <span slot="age" sb-mark="users