The worst bug ever: the shop gives discounts by itself - negative taxes - voucher bug

[Shin_P]

I really dont know how hard to bang my head on the wall this time.
I was going to launch my renewed website with prestashop within days but I've found this bug that's just driving me crazy.

Since the lack of documentation doesnt let me fix this by myself, I need your help asap.

So this is what happens: I add a voucher when checking out in a no-tax zone and the shop creates a negative tax!!




I just re-created the issue in a blank installation of PS, with the following configuration:



- 1 tax, 20% applied to one zone

- product tax with the above tax applied to the product

- two different zones, one with tax applied, one without

- no states taxes

- no states at all

- PS Version 1.3.1.1




If I don't enter any voucher everything is fine.

If I enter a voucher:

- if the zone is with tax everything is fine
- if the zone is without tax the shop creates a negative tax


The amount of this negative tax is the 20% of the price reduction given by the voucher (i.e. the tax applied to the reduction) but in that zone there's no tax at all!


Help me please (also willing to pay for help!! )

[rocky]

Have you reported this on the bug tracker?

[Shin_P]

Correct, I just reported it : http://www.prestashop.com/bug_tracker/view/5639/


By the way, I tought to make this workaround but I don't know where to edit the code.


Since it is the

$total_tax

variable wrong, something like this might work:

if ((($total_products_wt-$total_products)==0) && $total_discounts!=0)
{$total_tax==0}

Doing like "if the difference between total products with and without tax is null (there's no tax) and some discount is applied, then just make total taxes = 0.

But I don't know where to put it..

I tried in classes/cart.php on the

function getSummaryDetails()

but I believe Smarty doesnt like it so much..

The best will be correcting directly

function getordertotal

but that's too hard for me and my poor skills.

I'd be really grateful if someone could help me

[lpguillaume]

Hi,

I have the same issue on my e-commerce site.
I wanted to give volume discount and offer shipping costs to my on-line boutiques that resell my products. They are all located in the EU where I am also located
I have created a group of clients with price display without VAT that contains them. Then I have created for each of them a voucher with a price rebate above a minimum price. I also have created a voucher for free shipping costs above the same minimum price.

Variant of the bug:
When the vouchers are entered on the shopping basket, everything is fine.
When I chose to reduce the quantity of my oder and the price goes below the threshold of the free shipping costs, then the voucher continues to give free shipping costs !

I was able to replicate the bug on the PrestaShop Demo web site: http://www.prestashop.com/en/showcase_demo/

This bug creates a big issue!


Thanks,
LP

[ScubaLessonsInc]

Same issue.. I could not find your bug in the bug tracker so I created my own: http://forge.prestashop.com/browse/PSCFI-2797 as I am having a very similar issue.. I had a site getting tons of sales and working perfectly UNTIL I added a voucher to take 20% off all orders of 100$ or more. Only at that point did the tax show negative.

 

I know if you have a double positive it will create a negative. I have a feeling there is code in the voucher's php files or somewhere in that ball park creating the problem. The two adding of the positive taxes could be creating the negative by canceling each other out.

[ScubaLessonsInc]

I found this.. it may help.. It is the entire 1.3.7 prestashop software with fixes for negative taxes. I have never done an install over my current files successfully so I am afraid to try it. I found it on a website with a complaint just like ours as a solution. I am not sure which files exactly affect the checkout process/taxes and voucher but if you know.. here is your solution.

 

If anyone does or can use the files attached and solves this, please be kind enough to post here with very specific details about what files you replaced from this full corrected back up and how it was done.

 

Thanks and good luck.

Here is the link to the file: http://ledlites4rvs.com/img/prestashop_1.3.7.0_sp1_byInveostore.com.zip

Or you can get it online at www.Inveostore.com with full detail.