private static function getAttributes(SgmlOpenTag $tag)
{
$attributes = [];
foreach ($tag->getAttributesList() as $name => $value) {
if ($value === null) {
$quotedValue = null;
} else {
$quotedValue = '="' . str_replace('"', '"', $value) . '"';
}
$attributes[] = $name . $quotedValue;
}
return implode(' ', $attributes);
}
