Mock products and setting values on unit testing

Question

I've created an API extension that manages gallery easily for our demands and now I wanted to create a unit testing.

For example, one functionality is: give an 'sku' and 'entry' object (with base64 img) and API adds this image on that product.

This is the class I want to test:

<?php

namespace Gsp\ApiExtension\Model;

use Gsp\ApiExtension\Api\SGIMediaInterface;
use Magento\Framework\Api\ImageContentValidatorInterface;
use Magento\Catalog\Api\ProductAttributeMediaGalleryManagementInterface;
use Magento\Catalog\Api\Data\ProductAttributeMediaGalleryEntryInterface;
use Magento\Catalog\Api\ProductRepositoryInterface;
use Magento\Store\Api\StoreRepositoryInterface;
use Magento\Framework\App\ObjectManager;

class SGIMedia implements SGIMediaInterface {

    /**
     * @var StoreRepositoryInterface $storeRepository
     */
    protected $storeRepository;

    /**
     * @var ProductRepositoryInterface
     */
    protected $productRepository;

    /**
     * @var ImageContentValidatorInterface
     */
    protected $contentValidator;

    /**
     * @var ProductAttributeMediaGalleryManagementInterface
     */
    protected $galleryManagement;

    /**
     * @param StoreRepositoryInterface $storeRepository
     * @param ProductAttributeMediaGalleryManagementInterface $galleryManagement
     * @param ProductRepositoryInterface $productRepository
     * @param ImageContentValidatorInterface $contentValidator
     */
    public function __construct(StoreRepositoryInterface $storeRepository, ProductAttributeMediaGalleryManagementInterface $galleryManagement, ProductRepositoryInterface $productRepository, ImageContentValidatorInterface $contentValidator) {
        $this->productRepository = $productRepository;
        $this->contentValidator = $contentValidator;
        $this->galleryManagement = $galleryManagement;
        $this->storeRepository = $storeRepository;
    }

    /**
     * @inheritdoc
     */
    public function update($skus, ProductAttributeMediaGalleryEntryInterface $entry) {
        $sku_array = explode('|', $skus);

        foreach ($sku_array as $sku) {
            $this->galleryManagement->create($sku, $entry);
        }
    }

(...)

}

1) I need to mock a product, I've already did that, but then all attributes are NULL, so I would need to set an SKU at least. setData is not working. I'm stuck here.

I did this:

/**
* @var \Magento\Catalog\Model\Product
*/
protected $product;

protected function setUp() {
    $this->product = $this->createMock(\Magento\Catalog\Model\Product::class, [], [], '', false);

    $this->product->setSku('test');
    var_dump($this->product->getSku()); //returns NULL

    $this->product->setData('sku', 'test');
    var_dump($this->product->getData('sku')); //returns NULL

    $this->product->save();
    var_dump($this->product->getData('sku')); //returns NULL
 }

2) Then I get my model and call my method passing this SKU and a fixed entry as a parameters.

3) Verify the product has this entry.

By the way, I'm very new at unit testing and on Magento too.

Answer 1

Use $product->method('getSku')->willReturn('test'); Mocks can be configured in many ways! It is worth reading the documentation here: https://phpunit.de/manual/current/en/test-doubles.html

Answer 2

I believe it will be less complicated if we could separate the required logic to test in different methods and test that specific method using the PHPUnit framework when doing the TDD development.

For example, in your method update(), I can see two sections.

Section 1:

$sku_array = explode('|', $skus);

Section 2:

foreach ($sku_array as $sku) {
   $this->galleryManagement->create($sku, $entry);
}

So if you would need to add a unit test for section one, you can create a separate method called getExplodedSkus() for that section and use assertEquals() method (compare exploded array values) in PHPUnit. For section two, you can create another method called createGalleryItem() and use assertInstanceOf() method (verify $sku_array has product type objects) in PHPUnit.

FYI: PHP variable names have to be camelCase and not the snake_case. $sku_array should be $skuArray.

Hope this will help to make it less complex.

Cheers!