/**
     * testAddItem
     *
     * @return  void
     */
    public function testAddItem()
    {
        $this->instance->addItem('http://windwalker.io');
        $xml = <<<XML
<?xml version="1.0" encoding="utf-8"?>
<urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">
\t<url>
\t\t<loc>http://windwalker.io</loc>
\t</url>
</urlset>
XML;
        $this->assertDomStringEqualsDomString($xml, $this->instance->toString());
        $this->instance->addItem('http://windwalker.io/foo/bar/?flower=sakura&fly=bird', '1.0', ChangeFreq::DAILY, '2015-06-07 10:51:20');
        $xml = <<<XML
<?xml version="1.0" encoding="utf-8"?>
<urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">
\t<url>
\t\t<loc>http://windwalker.io</loc>
\t</url>
\t<url>
\t\t<loc>http://windwalker.io/foo/bar/?flower=sakura&amp;fly=bird</loc>
\t\t<changefreq>daily</changefreq>
\t\t<priority>1.0</priority>
\t\t<lastmod>2015-06-07T10:51:20+02:00</lastmod>
\t</url>
</urlset>
XML;
        $this->assertDomStringEqualsDomString($xml, $this->instance->toString());
    }
 /**
  * onAfterWriteFiles
  *
  * @return  void
  */
 public function onAfterWriteFiles()
 {
     include_once __DIR__ . '/../../vendor/autoload.php';
     $base = realpath(__DIR__ . '/../../..');
     $items = Folder::files($base, true);
     $sitemap = new Sitemap();
     $root = Ioc::getConfig()->get('site.root');
     $sitemap->addItem($root, 1.0);
     foreach ($items as $item) {
         if (File::getExtension($item) != 'html') {
             continue;
         }
         $loc = str_replace('\\', '/', substr($item, strlen($base) + 1));
         $sitemap->addItem($root . '/' . $loc, 0.8, ChangeFreq::WEEKLY, new \DateTime());
     }
     $xml = $sitemap->toString();
     file_put_contents($base . '/sitemap.xml', $xml);
 }