Laravel tesing: '$this->be()' not working

I'm writing some API tests for the platform I'm developing and I'm having issues trying to test the following route:

Route::post('/user/logout', ['middleware' => ['ACL', 'auth'], 'permission' => ['is_user'], 'uses' => 'UserController@logout']);

As you can see this route is using 2 middlewares: ACL and auth.

Every time the application environment is set to testing by Laravel the ACL is automatically disabled.

This is the the controller method logout():

public function logout()
{
    Auth::logout();

    return $this->respondOK('User logged out.');
}

And this is the test:

use Illuminate\Support\Facades\Auth;
use Illuminate\Support\Facades\Session;

class PostLogoutTest extends TestCase
{
    public function setUp()
    {
        parent::setUp();

        Session::start();

        $this->be(new \App\User());
    }

    public function tearDown()
    {
        Mockery::close();
    }

    public function testLogout()
    {
        Auth::shouldReceive('logout')->once()->withNoArgs()->andReturn();

        $response = $this->call('POST', '/api/user/logout', [
            '_token'   => csrf_token()
        ]);

        print_r($response->getContent());

        $this->assertResponseStatus(200);
    }
}

The problem I'm having is caused by the auth middleware and I keep receiving the following exception:

BadMethodCallException in EvalLoader.php code line 709: Method Mockery_2_Illuminate_Auth_AuthManager::driver() does not exist on this mock object

If I disable the auth everything works fine. Shouldn't $this->be() solve my issue?