Line Item taxable Property Resets After bulkCartUpdate

Extensions
1

We’re experiencing an issue where line item taxable properties are being reset to their original state after successfully updating them using bulkCartUpdate. The update appears to work initially but reverts after a few seconds.

Steps to Reproduce:

  1. Add a line item to the cart using addLineItem()

  2. Use bulkCartUpdate() to set taxable: false on all line items

  3. Observe that the update succeeds initially (confirmed via console logs)

  4. After 2-3 seconds, the line items revert to taxable: true

Code Implementation:

// Cart API setup
const { bulkCartUpdate, bulkAddLineItemProperties } = cart as CartApiContent;

// Update function
const bulkUpdateLineItemProperties = useCallback(async (lineItemUuid: string) => {
 const updatedLineItems = cartSubscription.lineItems.map((item: any) => ({
   ...item,
   taxable: false,
 }));

 // Update taxable property using bulkCartUpdate
 const response = await bulkCartUpdate({
   lineItems: updatedLineItems,
   cartDiscounts: cartSubscription.cartDiscounts || [],
   properties: cartSubscription.properties || {}
 });

Expected Behavior:

  • Line items should maintain taxable: false after the update
  • The bulkCartUpdate response should be persistent

Actual Behavior:

  • Line items temporarily show taxable: false

  • After 2-3 seconds, they revert to taxable: true

  • This happens even with loop prevention and proper state management

Debugging Information:

We’ve confirmed:

  • Cart Transform functions are disabled

  • No infinite loops in useEffect

  • bulkCartUpdate returns success response

  • bulkAddLineItemProperties executes without errors

  • No other cart operations are interfering

Any advice or suggestions would be very much appreciated :folded_hands:t5:

2

Hey @adamwooding, thanks for the report! I wanted to confirm, where are you observing this, is it through cartSubscription.lineItems? Also is it only the taxable field that is having this issue after the bulk update or does it affect any field?

3

Hi @Aaron_Schubert ,

Thank you very much for your reply. The line items tax reverting is actually just observable by eye by watching the cart. You can quite easily see the ‘tax-exempt’ sub-heading either appears or disappears, and the tax total down the bottom updates.

We haven’t tried any other fields using bulk update, so I’m unsure if it’s only this field or not.

Thank you so much for all your help :slight_smile:

4

Hey @Aaron_Schubert ,

Apologies for taking so long to reply about this. I’m just providing a screen recording and some futher information so hopefully this helps you to replicate the issue:

Shopify POS - Tax Issue - part 01
In this screen recording, we are adding an item to the cart, and then using the bulkCartUpdate function to change the item’s taxable setting. You will see that the item changes correctly for a moment, but then is changed back to its original setting:

Shopify POS - Tax Issue - part 02
In this screen recording, we are showing the results of the console log:

We’d love you to investigate this please Aaron, as we have a number of Plus merchants who would love us to create tax overrides to comply with certain local tax laws.

Thank you so much,
Adam