Shopping cart Rules doing the opposite - magento

Question

We have added a "yes/no" product attribute labelled: "Allow this product to have coupons applied?" with a default value of "yes".
The reason for this is, that we never want the sales team to give discounts on certain core products out of the thousands available.
We could add these products as SKU's to every one of the thousand coupons created, but that can then be changed by accident, or improperly listed by the sales team creating the coupons.
We therefore have asked them to add this rule to their new coupons, to exclude these products. We also updated all the other coupons via code, to include this rule.
When I test the rule on Magento 1.5, Community edition, it does exactly the opposite of what the condition says.
When I test the same rule on our other Enterprise solution (magento 1.9), it actually does what it is supposed to.
When I have one product in the shopping cart, being a product that has this attribute set to "No", and I apply a coupon code, it accepts the coupon code. On the other system (Enterprise) it rejects it, as it should.
Has anyone else came across this?
UPDATE:
Ok, this just got more interesting.
When I stepped through the Rule classes, the product was passed, but the product attribute did not come through. The scope is set to website, and I did check that is it saved under that scope in the back end.
This is really weird...
On the enterprise system, the product attribute, with the same configuration and data is coming through.
I even tried to not have double negatives, with another new attribute, to make sure.
Running against the following rule, the coupon gets refused: "Coupon code is not valid."
This is correct, as the product is set as "Can use coupon? = No".
But the problem is that I do not want to do a check against all the other products, but rather against, the few that has been marked as "No".
This is not going to work for us anyway, as we don't want to apply a coupon if there is any product in the cart that has a value of "No" for the attribute "Can use coupon?".
This is a double negative rule, no matter which way you look at it.
I stepped through /app/code/core/Mage/SalesRule/Model/Rule/Condition/Product.php through the validate() function, when adding the product a second time, and the data shows up in the attributes, but when I go and re-apply the coupon, and step through this function again, those values are gone. this is weird.
When adding new product to shopping cart:
When Re-applying Coupon Code:
Where the heck did description and some of the other attributes disappear to?
UPDATE NOTE I am getting a bit closer.
When I change the following validate() function in "/app/code/core/Mage/SalesRule/Model/Rule/Condition/Product.php" from the following:
public function validate(Varien_Object $object)
{
$product = false;
if ($object->getProduct() instanceof Mage_Catalog_Model_Product) {
$product = $object->getProduct();
} else {
$product = Mage::getModel('catalog/product')
->load($object->getProductId());
}
$product
->setQuoteItemQty($object->getQty())
->setQuoteItemPrice($object->getPrice())
->setQuoteItemRowTotal($object->getBaseRowTotal());
return parent::validate($product);
}
To This:
public function validate(Varien_Object $object)
{
$product = false;
$product = Mage::getModel('catalog/product')
->load($object->getProductId());
$product
->setQuoteItemQty($object->getQty())
->setQuoteItemPrice($object->getPrice())
->setQuoteItemRowTotal($object->getBaseRowTotal());
return parent::validate($product);
}
It then works fine!

Answer 1

Found out the actual problem, and here is what I did for the solution:
The following bit gets the product data for the Shopping Cart Price Rules:
if ($object->getProduct() instanceof Mage_Catalog_Model_Product) {
$product = $object->getProduct();
} else {
$product = Mage::getModel('catalog/product')
->load($object->getProductId());
}
The culprit is this line: $product = $object->getProduct();
That calls a line from the "Quote/Item/Abstract.php" being: $product = $this->_getData('product');
It will simply get the cached data from the system, and that consists of a selection like this:
$productCollection = Mage::getModel('catalog/product')->getCollection()
->setStoreId($this->getStoreId())
->addIdFilter($this->_productIds)
->addAttributeToSelect(Mage::getSingleton('sales/quote_config')->getProductAttributes())
->addOptionsToResult()
->addStoreFilter()
->addUrlRewrite()
->addTierPriceData();
The problem with this is, the following line:
->addAttributeToSelect(Mage::getSingleton('sales/quote_config')->getProductAttributes())
That will get only the attributes defined in the Config.xml for quote items being:
<quote>
<item>
<product_attributes>
<sku/>
<type_id/>
<name/>
<status/>
<visibility/>
<price/>
<weight/>
<url_path/>
<url_key/>
<thumbnail/>
<small_image/>
<tax_class_id/>
<special_from_date/>
<special_to_date/>
<special_price/>
<cost/>
<is_recurring/><!-- for totals calculation, placing and processing order -->
<recurring_profile/><!-- for placing order -->
<gift_message_available/>
</product_attributes>
</item>
</quote>
This will not get the new custom attribute that I want, and the rule will never be able to compare the data with the expected value properly.
Adding the following xml to my custom sales module config.xml, which have some observers in it for other stuff, fixes the problem.
<sales>
<quote>
<item>
<product_attributes>
<exclude_from_coupon/>
</product_attributes>
</item>
</quote>
</sales>
Then it all works!
Why did it work in the enterprise version of magento
Don't really know. I think Enterprise is maybe looking for settings on the actual Attribute definition, and includes it to the list of Attributes to collect, and then return the data for it, my guess. I will research that, and update it here to the post.
At least I now know what the real issue is, and why the Shopping Cart Rule Condition (coupon) failed.
Thanks to all those who helped me with some good questions and suggestions.
Another day wiser with magento...

Answer 2

I tested this with Magento CE 1.5.1.0 and cannot reproduce your problem. For me, it works.
Please recheck the following for your CE installation:
You set the default attribute value to "yes"
You did reindex the indexes as required.
You edited one test product and explicitly set the attribute value to "no".
(Just to be sure) You updated the caches.
You set the shopping cart price rule exactly as described above (apply if conditions are FALSE and allow is set to NO).
If you don't have any custom code interfering, this should work. It does in the default installation.
If it still doesn't work:
What happens if you rephrase the condition to only apply if all conditions are TRUE and allow is set to TRUE (does remove the double negative which is more complicated)?
Please post screenshots of the backend forms for shopping cart price rule, product attribute and the product.