Google Analytics throws Fatal Error

[alexh-swdev]

Preconditions (*)

1. OM 20.1.0
2. Multishop
3. Product in mulitple categories in multiple shops
4. PHP Version 8.1.16 (in docker)

Steps to reproduce (*)

1. Add such a product to cart

Expected result (*)

1. Product is added to cart without errors

Actual result (*)

Fatal error: Uncaught TypeError: Mage_GoogleAnalytics_Helper_Data::getLastCategoryName(): Return value must be of type string, null returned in /app/app/code/core/Mage/GoogleAnalytics/Helper/Data.php:186
Stack trace:
#0 /app/app/code/core/Mage/GoogleAnalytics/Model/Observer.php(88): Mage_GoogleAnalytics_Helper_Data->getLastCategoryName()

#1 /app/app/code/core/Mage/Core/Model/App.php(1441): Mage_GoogleAnalytics_Model_Observer->processItemsAddedOrRemovedFromCart()
#2 /app/app/code/core/Mage/Core/Model/App.php(1419): Mage_Core_Model_App->_callObserverMethod()
#3 /app/app/Mage.php(509): Mage_Core_Model_App->dispatchEvent()
#4 /app/app/code/core/Mage/Core/Model/Abstract.php(509): Mage::dispatchEvent()
#5 /app/app/code/core/Mage/Sales/Model/Quote/Item.php(788): Mage_Core_Model_Abstract->_afterSave()
#6 /app/app/code/core/Mage/Core/Model/Abstract.php(380): Mage_Sales_Model_Quote_Item->_afterSave()
#7 /app/app/code/core/Mage/Sales/Model/Quote/Item.php(771): Mage_Core_Model_Abstract->save()
#8 /app/app/code/core/Mage/Core/Model/Resource/Db/Collection/Abstract.php(643): Mage_Sales_Model_Quote_Item->save()
#9 /app/app/code/core/Mage/Sales/Model/Quote.php(380): Mage_Core_Model_Resource_Db_Collection_Abstract->save()
#10 /app/app/code/core/Mage/Core/Model/Abstract.php(380): Mage_Sales_Model_Quote->_afterSave()
#11 /app/app/code/core/Mage/Sales/Model/Quote.php(2087): Mage_Core_Model_Abstract->save()
#12 /app/app/code/core/Mage/Checkout/Model/Cart.php(450): Mage_Sales_Model_Quote->save()
#13 /app/app/code/core/Mage/Checkout/controllers/CartController.php(229): Mage_Checkout_Model_Cart->save()
#14 /app/app/code/core/Mage/Core/Controller/Varien/Action.php(421): Mage_Checkout_CartController->addAction()
#15 /app/app/code/core/Mage/Core/Controller/Varien/Router/Standard.php(255): Mage_Core_Controller_Varien_Action->dispatch()
#16 /app/app/code/core/Mage/Core/Controller/Varien/Front.php(181): Mage_Core_Controller_Varien_Router_Standard->match()
#17 /app/app/code/core/Mage/Core/Model/App.php(358): Mage_Core_Controller_Varien_Front->dispatch()
#18 /app/app/Mage.php(743): Mage_Core_Model_App->run()
#19 /app/index.php(71): Mage::run()
#20 {main} thrown in /app/app/code/core/Mage/GoogleAnalytics/Helper/Data.php on line 186

Possible Fix

The problem is, that the _categorieIds contains ALL its categories, of all its subshops. The poped category is not from the subshop from where it is added to the cart. Probably that's why the category is not loaded and its name is null.

These are just examples on the top of my head, but you are more into the whole OM code and its workflow
Adjust

Mage_GoogleAnalytics_Helper_Data::getLastCategoryName($product): string

to either allow null:

Adjust Mage_GoogleAnalytics_Helper_Data::getLastCategoryName($product): ?string

or loop through the categories until a valid one is found from

    /**
     * Returns last category name
     *
     * @param Mage_Catalog_Model_Product $product
     * @return string
     */
    public function getLastCategoryName($product): string
    {
        $_categoryIds = $product->getCategoryIds();
        if ($_categoryIds) {
            $_lastCat = array_pop($_categoryIds);
            $_cat = Mage::getModel('catalog/category')->load($_lastCat);
            return $_cat->getName();
        }
        return '';
    }

to

$_categoryIds = $product-getCategoryIds();
if ($_categoryIds) {
	$catName = "";
	do {
		$_lastCat = array_pop($_categoryIds);
		$_cat = Mage::getModel('catalog/category')-load($_lastCat);
		$catName = $_cat-getName();
	} while(empty($catName));
	return $catName ?? "";
}
return '';

[fballiano]

I like the last implementation, @daboss84 would you create a PR?

[alexh-swdev]

Good morning @fballiano , I created your requested pull request.

[fballiano]

Thanks @daboss84 , I’m out for a few days but I’ll check it out asap!