fix: DOMParser cannot see element with id="0"

Author: kenjis

system/Test/DOMParser.php

@@ -189,23 +189,23 @@ protected function doXPath(?string $search, string $element, array $paths = [])
         $path = '';
 
         // By ID
-        if (! empty($selector['id'])) {
-            $path = empty($selector['tag'])
+        if (isset($selector['id'])) {
+            $path = ($selector['tag'] === '')
                 ? "id(\"{$selector['id']}\")"
                 : "//{$selector['tag']}[@id=\"{$selector['id']}\"]";
         }
         // By Class
-        elseif (! empty($selector['class'])) {
-            $path = empty($selector['tag'])
+        elseif (isset($selector['class'])) {
+            $path = ($selector['tag'] === '')
                 ? "//*[@class=\"{$selector['class']}\"]"
                 : "//{$selector['tag']}[@class=\"{$selector['class']}\"]";
         }
         // By tag only
-        elseif (! empty($selector['tag'])) {
+        elseif ($selector['tag'] !== '') {
             $path = "//{$selector['tag']}";
         }
 
-        if (! empty($selector['attr'])) {
+        if (isset($selector['attr'])) {
             foreach ($selector['attr'] as $key => $value) {
                 $path .= "[@{$key}=\"{$value}\"]";
             }