Issue-39329-Invalid SKU Handling for Linked Products in Magento

[Syamsg]

Description (*)

Invalid SKU Handling for Linked Products in Magento.
In Magento, it’s possible to save a product SKU as "0." However, an issue occurs when this product is added as a linked product (such as Related Products, Up-Sells, or Cross-Sells) to another product. When attempting to make changes to the main product, it triggers an error: "The linked product SKU is invalid. Verify the data and try again."

Related Pull Requests

Fixed Issues (if relevant)

1. Fixes Invalid SKU Handling for Linked Products in Magento #39329

Manual testing scenarios (*)

• Scenario : Save a Product with a Related Product Having SKU '0'

1. Set up Related Product with SKU '0':

   • First, create or identify a product with SKU set to '0'.
   • Ensure this product is saved successfully in the system (assuming SKU '0' is valid for related products).

2. Navigate to the Product to be Edited:

   • Go to the Admin panel.
   • Access Catalog > Products and select the product you intend to edit.

3. Add Related Product:

   • In the Related Products, Up-sells, and Cross-sells section, add the product with SKU '0' as a related product.

4. Make an Edit to the Main Product:

   • Change any attribute of the main product, such as Name or Price.
   • Do not make changes to the SKU field.

5. Save the Product:

   • Click Save.

6. Expected Result:

   • The product should save successfully without any errors.
   • The presence of a related product with SKU '0' should not prevent saving.
   • Verify that the related product with SKU '0' remains correctly linked to the main product.

Questions or comments

If a product with SKU 0 already exists, we should be able to add this product as a related product to other products.

[m2-assistant]

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[hostep]

Is it really needed to prevent products with SKU "0" to be created? Also won't this cause issues for people who already have a product with SKU "0" that works fine, but when they want to update some value on it, your new code might prevent them doing so?

Your other changes will solve the linking problem, so I don't think we should prevent SKU "0" from being created? Or are there other cases that go wrong with a product that has an SKU of "0"?

[Syamsg]

I understand your point. Allowing SKU 0 is generally acceptable, as it’s unique, so only one product would have it. However, there could be potential issues since 0 may sometimes be interpreted as empty or false in programming contexts. Blocking 0 could also disrupt users who already use it. Unless we encounter specific issues in integrations, there’s no strong reason to prevent it, especially if other changes address linking concerns. Therefore, we don't necessarily need to prevent SKU 0, and I will add the required changes.

[Syamsg]

Reverted the changes I made to restrict saving a product with SKU '0.'