Impact: minor
Type: bugfix

Issue

#4955 and #4965 added the ability for tax services to return customFields in the response. A couple bugs were found after merging.

• When calculating for a cart, customFields on cart items and on taxSummary were not saved to the database
• When calculating for an order, customFields on cart items were not saved to the database

Solution

All customFields returned by a tax service at any level are now saved in the database, for both cart and order.

On cart and order items, the field name in the database is customTaxFields as opposed to customFields because otherwise it would be unclear that they're related to taxes since they're saved directly on the item object. The tax service should still return them as customFields; the field name change is only in the database.

Breaking changes

None

Testing

1. Temporarily update the calculateOrderTaxes function in the taxes-rates plugin to include customFields objects in the taxSummary, in one of the itemTaxes objects, and in one of the taxes objects.
2. Add items to a cart and begin checking out, using a destination address for which the shop collects taxes.
3. Once you see a tax amount on the checkout page, look in MongoDB to verify that all three expected customFields objects were saved in the Cart document.
4. Finish checking out. Look in MongoDB to verify that all three expected customFields objects were saved in the Order document.