Quantity Discounts not calculating correctly using mixed attribs

Hello all. I'm using the built in quantity discounts feature of Zencart. For some reason, I'm having issues though with the discount calculation.

example. I have a product that goes from 18.50 to 18.00 when you buy 6 or more.

If I purchase 3 of one attribute set, it sets the 3 at 18.50 each (correct).
If I then purchase 3 more of another attribute set (color, size), then those 3 are correctly priced at 18.00 each, but the previous 3 remain at 18.50 each (incorrect).

If, on the other hand, I purchase 6 of one attribute set, then the cost is correctly calculated at 18.00 each.

Using zencart 1.3.6.

Any advice would be appreciated.

Have you an URL to this product that we could peek at please?

sure:

http://www.weecarediapercompany.com/weecart/index.php?main_page=product_info&products_id=90

you can choose a combination of small blue and small forest.

If you select 6 of either one, you get the correct discount. If you split them 3 of each.. well.. you'll see... :)

a small addition. we have 5 different products with the same pricing / discount structure and they're all having the same problem.

one other addition.

if you add an unrelated item to the cart, then the discount is removed entirely. not even the 3 which were correct will show the discounted value.

if you then add another of the same discounted product, that single one will show the correct discounted price, but not the other two attribute groups.

very strange.

Are you using a Stock-handling add-on for this?

I have not seen a problem with Product Quantity Discounts ...

I set up this same scenario without a stock track and no problems ... at least I am guessing that color list with the quantities means something?

the only stock add-on we're using is the Stock By Attributes. I've asked in that support thread and apparently it doesn't touch the quantity discount functionality.

I've been using winmerge to try to find some changes in the various php files that could be causing the issue, but I'm having a difficult time following the program flow after the add to cart button is clicked and how it then refreshes the prices with quantity discount taken into account. Not sure which php is responsible for doing the recalc and re-display of the item costs.

As a test earlier today, I installed a new version of zencart 1.3.8, connected it to a copy of the current database. I upgraded the database to 1.3.8 and installed only the Stock By Attributes add-on.

Same problem.

ok, now I'm stuck.

I've uploaded and installed a fresh copy of zen cart 1.3.8a.
I've let it create a brand new database.
I've added one product with a quantity discount applied.
It does NOT work.

Fresh database. Fresh cart. Still unable to calculate qty discounts properly.

I think I've eliminated the program and any possible database corruption. Where do I look next?

Could there be something on the server?

http://www.weecarediapercompany.com/store

try this edit:

/includes/classes/shopping_cart.php
at lines 1401 and 1435 you have code that looks like this:// reset($this->contents); // breaks cart $check_contents = $this->contents; while (list($products_id, ) = each($check_contents)) {add an extra line in both places, making it look like this:```
// reset($this->contents); // breaks cart
$check_contents = $this->contents;
[B] reset($check_contents);[/B]
while (list($products_id, ) = each($check_contents)) {

That was the solution!!!

Has this issue not come up before? Are we selling in an unusual way? Either way, I'm very grateful for your solution!!!

Thank you very much!!!!

DrByte:

try this edit:

/includes/classes/shopping_cart.php
at lines 1401 and 1435 you have code that looks like this:

I have Zen Cart v1.3.7.1 and noticed that identical products
with different attributes
are seen as different products regarding product discount.

Product 1 with Attribute option 1 (chosen attribute value = 1)
and
Product 1 with Attribute option 1 (but now attribute value = 2 is chosen)
won't get a Quantity Discount. It's like they are seen as seperate (and not identical) products.

Do I have to configure something in order to accomplish that those products with different chosen attribute values are see as the same product for Quantity Discount?
Or can I use DrByte's modification in /includes/classes/shopping_cart.php to get it like that?

I don't know for sure.
But it's safe to make the edit I suggested in my earlier post. It's actually applicable to 1.3.6 and 1.3.7.x and 1.3.8.x

DrByte:

But it's safe to make the edit I suggested in my earlier post. It's actually applicable to 1.3.6 and 1.3.7.x and 1.3.8.x

Yes, I used your modification in 1.3.7.x and now it works correctly!
Thank you for this information!