When using a Cart Discount with CartDiscountPatternTarget that defines a triggerPattern, (Custom) Line Items on a Cart or Order now indicate whether they are involved in the discount as a trigger or target. With this enhancement, you can now build features such as custom proration during returns and reporting on which items drove a marketing campaign.

The discountedPricePerQuantity of the trigger (Custom) Line Item also includes a zero-amount discount alongside the reference to the applied Cart Discount. The zero-amount discount signals that the item participated in triggering the discount without receiving a price reduction. Previously, discountedPricePerQuantity only held an entry for the discount on the target (Custom) Line Item.