DiDom\Document::count PHP Метод

    public function count($expression, $type = Query::TYPE_CSS)
    {
        $xpath = new DOMXPath($this->document);
        $expression = Query::compile($expression, $type);
        $expression = sprintf('count(%s)', $expression);
        return $xpath->evaluate($expression);
    }

 public function testCount()
 {
     $html = '<ul><li>One</li><li>Two</li><li>Three</li></ul>';
     $document = new Document($html, false);
     $this->assertEquals(3, $document->count('li'));
     $document = new Document();
     $this->assertEquals(0, $document->count('li'));
 }