public function testReferenceMany()
{
$adminGroup = new Group('Admin');
$techGroup = new Group('Tech');
$user = $this->createTestObject();
$this->objectManager->persist($adminGroup);
$this->objectManager->persist($techGroup);
$this->objectManager->persist($user);
$user->setUsername('ryanweaver');
$user->addGroup($adminGroup);
$user->addGroup($techGroup);
$this->objectManager->flush();
$this->objectManager->clear();
$user = $this->objectManager->find($this->userClassName, $user->getId());
$this->assertCount(2, $user->getGroups());
$groups = $user->getGroups();
$this->assertEquals('Admin', $groups[0]->getName());
$this->assertEquals('Tech', $groups[1]->getName());
$moderatorGroup = new Group('Moderator');
$user->addGroup($moderatorGroup);
$this->objectManager->persist($moderatorGroup);
$this->objectManager->flush();
$this->objectManager->clear();
$user = $this->objectManager->find($this->userClassName, $user->getId());
$this->assertCount(3, $user->getGroups());
$this->assertEquals('Moderator', $groups[2]->getName());
}