think\console\Output::writeln PHP Method

    public function writeln($messages, $type = self::OUTPUT_NORMAL)
    {
        $this->write($messages, true, $type);
    }

 protected function execute(Input $input, Output $output)
 {
     if ($input->hasOption('config')) {
         $build = (include $input->getOption('config'));
     } else {
         $build = (include APP_PATH . 'build.php');
     }
     if (empty($build)) {
         $output->writeln("Build Config Is Empty");
         return;
     }
     \think\Build::run($build);
     $output->writeln("Successed");
 }