/**
  * Test when getting products from multiple categories.
  */
 public function testGettingProductsFromMultipleCategories()
 {
     /**
      * @var $rootCategory CategoryInterface
      */
     $rootCategory = $this->categoryRepository->findOneBy(['slug' => 'root-category']);
     $category = $this->categoryRepository->findOneBy(['slug' => 'category']);
     $products = $this->productRepository->getAllFromCategories([$rootCategory, $category]);
     $this->assertCount(3, $products, 'It should only return one product on the root category');
 }