php - Laravel中类中的构造函数传参是可以自动new一个传递进去的吗？

Question

这是Laravel中Auth\Guard的构造函数：

    /**
     * Create a new authentication guard.
     *
     * @param  \Illuminate\Auth\UserProviderInterface  $provider
     * @param  \Illuminate\Session\Store  $session
     * @param  \Symfony\Component\HttpFoundation\Request  $request
     * @return void
     */
    public function __construct(UserProviderInterface $provider,
                                SessionStore $session,
                                Request $request = null)
    {
        $this->session = $session;
        $this->request = $request;
        $this->provider = $provider;
    }

其中传入了参数SessionStore $session
但是session的构造函数是这样的:

public function __construct($name, SessionHandlerInterface $handler, $id = null)
    {
        $this->setId($id);
        $this->name = $name;
        $this->handler = $handler;
        $this->metaBag = new MetadataBag;
    }

这里是有参数的，为什么Guard的构造函数可以自动生成session?
是php原生提供的还是Laravel提供的?

Answer 1

https://github.com/laravel/framework/blob/4.2/src/Illuminate/Auth/AuthManager.php#L51

Answer 2

/**
 * Create an instance of the Eloquent driver.
 *
 * @return \Illuminate\Auth\Guard
 */
public function createEloquentDriver()
{
    $provider = $this->createEloquentProvider();

    return new Guard($provider, $this->app['session.store']);
}