public function testFirstChild()
{
$html = '<ul><li>One</li><li>Two</li><li>Three</li></ul>';
$document = new Document($html, false);
$list = $document->first('ul');
$this->assertEquals($list->getNode()->firstChild, $list->firstChild()->getNode());
$list = new Element('ul');
$this->assertNull($list->firstChild());
// with text nodes
$html = '<p>Foo <span>Bar</span> Baz</p>';
$document = new Document($html, false);
$paragraph = $document->first('p');
$firstChild = $paragraph->getNode()->firstChild;
$this->assertEquals($firstChild, $paragraph->firstChild()->getNode());
}