Can't display a form in embed view - php

Question

I got an issue to display a form in popup view. I have read the Symphony documentation and created a bundle to store my form. Then in the base controller I have tried to load it...
I got the following error:
Variable "form" does not exist in nostalgie90sloginUserBundle:Default:loginUser.html.twig at line 1
I want to display this form in a popup using leanModal jquery
The base file where the main view is loaded
base.html.twig:
//some stuff of the base
//....
<div id="loginmodal" style="display:none;">
<p> MON FORMULAIRE </p>
<!--{{ include ("nostalgie90sloginUserBundle:Default:loginUser.html.twig") }} -->
{{ render(controller('nostalgie90sloginUserBundle:Default:new')) }}
</div>
</a>
My controller where the form is loaded:
class DefaultController extends Controller//login bundle
{
public function newAction()
{
$user = new User90s();
$form = $this->createForm(new LoginForm(), $user);
return $this->render('nostalgie90sloginUserBundle:Default:loginUser.html.twig', array('form' => $form->createView(), ));
}
public function indexAction($name)
{
}
}
My form class:
class LoginForm extends AbstractType
{
public function buildForm(FormBuilderInterface $builder, array $options)
{
$builder->add('login');
$builder->add('password');
$builder->add('mail');
}
public function getName()
{
return 'login';
}
public function getDefaultOptions(array $options)
{
return array('data_class' => 'nostalgie90s\BaseBundle\Entity\User90s', );
}
}
And finally the view of the form loginUser.html.twig:
{{ form_start(form) }}
{{ form_errors(form) }}
{{ form_row(form.login) }}
{{ form_row(form.password) }}
<input type="submit" />
{{ form_end(form) }}