Doctrine\Tests\Models\ECommerce\ECommerceProduct::addCategory PHP Метод

    public function addCategory(ECommerceCategory $category)
    {
        if (!$this->categories->contains($category)) {
            $this->categories[] = $category;
            $category->addProduct($this);
        }
    }

 public function testSavingClonedPersistentCollection()
 {
     $product = new ECommerceProduct();
     $category = new ECommerceCategory();
     $category->setName('foo');
     $product->addCategory($category);
     $this->_em->persist($product);
     $this->_em->persist($category);
     $this->_em->flush();
     $newProduct = clone $product;
     $this->_em->persist($newProduct);
     $this->_em->flush();
     $this->_em->clear();
     $product1 = $this->_em->find('Doctrine\\Tests\\Models\\ECommerce\\ECommerceProduct', $product->getId());
     $product2 = $this->_em->find('Doctrine\\Tests\\Models\\ECommerce\\ECommerceProduct', $newProduct->getId());
     $this->assertCount(1, $product1->getCategories());
     $this->assertCount(1, $product2->getCategories());
     $this->assertSame($product1->getCategories()->get(0), $product2->getCategories()->get(0));
 }