public function testAcceptsForeignKeysAsCriteria()
{
$customer = new ECommerceCustomer();
$customer->setName('John Doe');
$cart = new ECommerceCart();
$cart->setPayment('Credit card');
$customer->setCart($cart);
$this->_em->persist($customer);
$this->_em->flush();
$this->_em->clear();
unset($cart);
$class = $this->_em->getClassMetadata('Doctrine\\Tests\\Models\\ECommerce\\ECommerceCart');
$persister = $this->_em->getUnitOfWork()->getEntityPersister('Doctrine\\Tests\\Models\\ECommerce\\ECommerceCart');
$newCart = new ECommerceCart();
$persister->load(array('customer_id' => $customer->getId()), $newCart, $class->associationMappings['customer']);
$this->assertEquals('Credit card', $newCart->getPayment());
}