   });
        });

        suite('DocumentFragment', function () {
          test('Appends an element', () => {
            const container = document.createDocumentFragment();
            container.appendChild(document.createElement('div'));

            const child = document.createElement('div');
            container.append(child);

            assert(child.parentNode === container);
            assert(container.childNodes.length === 2);
            assert(container.childNodes[1] === child);
          