 multiple types of nodes', () => {
            const container = document.createDocumentFragment();
            container.appendChild(document.createElement('div'));

            const child1 = document.createElement('div');
            const child3 = document.createElement('div');
            container.append(child1, 'This is some text.', child3);

            assert(container.childNodes.length === 4);
            assert(container.childNodes[1] === child1);
            assert(container.childNodes[2].nodeTy