Here ya go Daniel

gistfile1.txt

<?php

/**
 * @file
 * Definition of Drupal\system\Tests\Session\SessionSymfony2Test.
 */

namespace Drupal\system\Tests\Session;

use Drupal\simpletest\DrupalUnitTestBase;

class SessionSymfony2Test extends DrupalUnitTestBase {

  public static function getInfo() {
    return array(
      'name' => 'Symfony2 Session tests',
      'description' => 'Test our use of Symfony2 Sesion objects',
      'group' => 'Session'
    );
  }

  /**
   * Tests the new session API and handling
   */
  function testDICSession() {
    $session = drupal_container()->get('session');
    $this->verbose($session);

    // Does the session exist?
    $this->assertTrue($session, "The Symfony2 Session exists.");

    // Can I log in?
    $session->start();
    $this->assertTrue

    // Can I log out?

    // Can I save data in a session?

  }
}