Laravel\Envoy\TaskContainer::hasOneServer PHP Method

    public function hasOneServer()
    {
        return count($this->servers) == 1;
    }

 /**
  * Get the server from the task container.
  *
  * @param  \Laravel\Envoy\TaskContainer  $container
  * @return string
  */
 protected function getServer(TaskContainer $container)
 {
     if ($this->argument('name')) {
         return $container->getServer($this->argument('name'));
     } elseif ($container->hasOneServer()) {
         return $container->getFirstServer();
     } else {
         throw new \InvalidArgumentException('Please provide a server name.');
     }
 }