PHPCfg\ParserTest::canonicalize PHP Method

    private function canonicalize($str)
    {
        // trim from both sides
        $str = trim($str);
        // normalize EOL to \n
        $str = str_replace(["\r\n", "\r"], "\n", $str);
        // trim right side of all lines
        return implode("\n", array_map('rtrim', explode("\n", $str)));
    }