Varien_Autoload::searchFullPath PHP Метод

    public static function searchFullPath($filename)
    {
        // return stream_resolve_include_path($filename);
        $paths = explode(PATH_SEPARATOR, get_include_path());
        foreach ($paths as $path) {
            $fullPath = $path . DIRECTORY_SEPARATOR . $filename;
            if (file_exists($fullPath)) {
                return $fullPath;
            }
        }
        return false;
    }