public function testCreateAndRetrieve()
{
$root = Category::getRootNode();
$list = ProductList::getNewInstance($root);
$list->save();
$list2 = ProductList::getNewInstance($root);
$list2->save();
$lists = ProductList::getCategoryLists($root);
$this->assertSame($lists->get(0), $list);
$this->assertSame($lists->get(1), $list2);
$this->assertEqual($list->position->get(), 0);
$this->assertEqual($list2->position->get(), 1);
}