I'm doing some customizations to a non-stock shipping module and am running into a little problem. When shipping is configured to be taxed it is coming in off by a penny sometimes, it's a rounding issue and after a bunch of testing I have narrowed it to the tax added from shipping. So, on the checkout page the combined tax in the cart is off if it should be rounded up, such as $4.2567 is what is calculated at the configured tax rate. It's returning $4.25 instead of $4.26. I need to know where the shipping tax is added to the total tax so I can see if it's using zen_round. I've been looking around for hours and hours now trying to figure out where the shipping tax is calculated and also where it's added to the product tax to get the total. It has been a really long time since I did some serious zen coding and I am pretty rusty with the structure of how it all ties together. I've been looking in class and function files but haven't located it.
Can you please point out which file(s) I need to be checking for the shipping tax calculation and where it's added to the cart tax?
Bookmarks