Symfony\Component\BrowserKit\Client::submit PHP Method

    public function submit(Form $form, array $values = array())
    {
        $form->setValues($values);

        return $this->request($form->getMethod(), $form->getUri(), $form->getPhpValues(), $form->getPhpFiles());
    }

 protected function login(Client $client, $username = '******', $password = '******')
 {
     $client->restart();
     $crawler = $client->request('GET', '/login');
     $this->assertTrue($client->getResponse()->isSuccessful(), 'Response should be successful');
     $form = $crawler->selectButton('Login')->form();
     $client->submit($form, array('_username' => $username, '_password' => $password));
     $this->assertTrue($client->getResponse()->isRedirect(), 'Response should be redirect');
     $crawler = $client->followRedirect();
     $this->assertGreaterThan(0, $crawler->filter('html:contains("Benvenuto")')->count());
 }