public function testUser()
{
$businessUnit = new BusinessUnit();
$user = new User();
$businessUnit->setUsers(new ArrayCollection(array($user)));
$this->assertContains($user, $businessUnit->getUsers());
$businessUnit->removeUser($user);
$this->assertNotContains($user, $businessUnit->getUsers());
$businessUnit->addUser($user);
$this->assertContains($user, $businessUnit->getUsers());
}