public function npmInstall()
    {
        $inputOutput = $this->inputOutput;

        if ($inputOutput->isVerbose()) {
            $inputOutput->write(sprintf('<info>%s</info>', 'Installing NPM-Packages for Coding-Standard'));
        }

        if ($inputOutput->isVeryVerbose()) {
            $inputOutput->write(sprintf('Executed Command: <info>%s</info>', $this->process->getCommandLine()));
        }

        $inputOutput->write('<info>NPM install</info> for zooroyal/coding-standard:');
        $this->process->run(
            function ($type, $buffer) use ($inputOutput) {
                $inputOutput->write($buffer);
            }
        );

        $this->process->wait();

        $inputOutput->write('<info>NPM packages installed</info> for zooroyal/coding-standard');
    }