LoginListener.php

    protected $event = null;

    public function onSecurityInteractiveLogin(InteractiveLoginEvent $event)
    {
        $this->event = $event;
        $username = $this->getUsername();
        $session = $this->getSession();
        $this->setFlash($session, $username);
    }
    protected function getUsername()
    {
        return $this->event->getAuthenticationToken()->getUsername();
    }
    protected function getSession()
    {
        return $this->event->getRequest()->getSession();
    }
    public function setFlash($event, $username)
    {
        $session->setFlash('notice', "Welcome {$username}, you have successfully logged in.");
    }

LoginListenerTest.php

    public function testOnSecurityInteractiveLogin()
    {
        $loginEvent = new LoginListener();
        
        // Get a mock $event of type InteractiveLoginEvent
        
        $loginEvent->onSecurityInteractiveLogin($event);
    }



class LoginListenerStub extends LoginListener
{
    protected username = null;
    protected session = null;


    public setUsername($username) { $this->username = $username; }
    public setSession($session) { $this->session = $session; }
}