Incorrect tax

[daphilli224]

Editing the shipping cost results in an incorrect tax calculation when the order includes a taxable item and a non-taxed item. The reported tax depends on the order of the taxable and non-taxed item in the order. If the non-taxed item is first in the order, the reported tax after editing the shipping cost is the tax on the shipping. If the taxable item is first in the order, the reported tax after editing the shipping cost is the tax on the total order (including the non-taxable item). The shipping cost is taxed at the same rate as the taxable item. Only one tax rate. The problem is repeatable. Group discount and quantity discount are not involved in these orders. I have EO logs which I'll scrub and submit later. No errors logged in creating the orders or in admin editing the orders.

Dave
zc2.1.0, edit orders 5.0.2

[daphilli224]

EO log files and before and after shipping cost edit screenshots are attached. In each case, the shipping cost was edited to $10.01. The edits were not committed so the logs and screenshots reflect actions up to but not commit.
Dave

eo_debug_taxable followed by non-taxable.log
eo_debug_14739_non-taxable followed by taxable.log

[daphilli224]

I looked at a few variables in function calculateTaxForProduct in the order class when purchasing the taxable and non-taxable products, and again after editing the shipping charge in EO. The case tested is the one where the tax after editing the shipping charge ended up being the tax on everything, including the non-taxable product.

The variable $this->info['tax_subtotals'] after processing both products when purchasing was array ('PA Sales Tax 6%'=>array ('tax_rate'=>6.0,'subtotal'=>19.99,),'Sales Tax'=>array ('tax_rate'=>0,'subtotal'=>16.0)).

After editing the shipping charge, the same variable was array ('PA Sales Tax 6%'=>array ('tax_rate'=>6.0,'subtotal'=>35.99,)). Six percent of 35.99 represents the tax on both products. So the tax description of Sales Tax was not included.

Looking at tax_groups in $this->products($index) in the same function revealed that after editing the shipping charge, was 'tax_groups'=>array ('PA Sales Tax 6.0%' => 6.0) for the taxable product, and 'tax_groups'=>array ('PA Sales Tax 6.0%'=>0.0) for the non-taxable product. When purchasing, tax_groups for the taxable product was 'tax_groups'=>array ('PA Sales Tax 6.0%' => 6.0), and was 'tax_groups'=>array ('Sales Tax'=>0.0) for the non-taxable product.

It seems that the tax description needs to change as well as the tax rate for each product in EO.

Dave

[daphilli224]

I think I found the problem and a fix. The problem is in line 816 of function findTaxGroupNameFromValue in zc_plugins/EditOrders/v5.0.2/admin/includes/classes/EditOrders.php. The line is "if ($num_tax_groups === 1 || ($tax_info['tax_rate'] !== false && $tax_info['tax_rate'] == $value)) {".

I believe the line should be "if ($num_tax_groups >= 1 && ($tax_info['tax_rate'] !== false && $tax_info['tax_rate'] == $value)) {". Reasons: (1) the "or" test in the line prevents the code from adding a record to the order's tax-groups and tax-subtotals into which non-taxed products (or shipping) can be accumulated when the non-taxable item follows a taxable item, and (2) the test on $num_tax_groups === 1 prevents the $group_name from being applied to a taxable product if it follows a non-taxable product and the record for non-taxed items has been previously entered.

The fix was tested with various combinations and numbers of taxable and non-taxable products and works in each case. But only my tax situation was tested, where only one tax and tax rate that is applied to both taxable products and shipping exists. Multiple tax rate situations were not tested.

I also want to say that Edit Orders is a great piece of work. I'm truly amazed with the UI and complexity of the coding. Thank you Cindy!

Dave