ancestors example

public function testFilterXPath()
    {
        $crawler = $this->createTestCrawler();
        $this->assertNotSame($crawler, $crawler->filterXPath('//li'), '->filterXPath() returns a new instance of a crawler');
        $this->assertInstanceOf(Crawler::class, $crawler->filterXPath('//li'), '->filterXPath() returns a new instance of a crawler');

        $crawler = $this->createTestCrawler()->filterXPath('//ul');
        $this->assertCount(6, $crawler->filterXPath('//li'), '->filterXPath() filters the node list with the XPath expression');

        $crawler = $this->createTestCrawler();
        $this->assertCount(3, $crawler->filterXPath('//body')->filterXPath('//button')->ancestors(), '->filterXpath() preserves ancestors when chained');
    }

    public function testFilterRemovesDuplicates()
    {
        $crawler = $this->createTestCrawler()->filter('html, body')->filter('li');
        $this->assertCount(6, $crawler, 'The crawler removes duplicates when filtering.');
    }

    public function testFilterXPathWithDefaultNamespace()
    {
        $crawler = $this->createTestXmlCrawler()->filterXPath('//default:entry/default:id');