private function npm()
    {
        $cmd = new Command('cd');
        $cmd->addParam($this->installDir)
            ->addSubCommand('&&')
            ->addSubCommand('npm')
            ->addParam('update');

        return $this->ex($cmd);
    }
private function npm()
    {
        $cmd = new Command('cd');
        $cmd->addParam($this->installDir)
            ->addSubCommand('&&')
            ->addSubCommand('npm')
            ->addParam('update');

        return $this->ex($cmd);
    }
private function npm ( ) { $ cmd = new Command ( 'cd' ) ; $ cmd -> addParam ( $ this -> installDir ) -> addSubCommand ( '&&' ) -> addSubCommand ( 'npm' ) -> addParam ( 'update' ) ; return $ this -> ex ( $ cmd ) ; }
Run npm update.

@return bool True if npm is successful. False otherwise.
Run npm update .