Discount missing from Sections API response when using order_discount function, sometimes

[davidhollenbeck]

I'm noticing some strange behavior when multiple discounts are returned using order_discount api with DiscountApplicationStrategy::MAXIMUM. Curious if anyone else has seen something like this..

I'm porting a standard 3-tier discount from a Ruby script for a client. When the cart total is $100+ in $10 discount, $200+, $20 discount, $300+, $30 discount. About as simple as it gets.

Wrote & deployed the script and testing on the default 'Test Data' theme ( Dawn 11.0.0). The environment is a dev store w/extensibility preview build. In checkout, everything works fine, but on the online storefront I'm noticing the discount is sometimes dropped from the section api response when using the <cart-drawer> component from Dawn

Specifically, whenever I increase the quantity in cart from 1 to 2, the order discount disappears from the cart drawer. However, it appears again when I change the quantity of 1, 3, and 4. if I refresh, the discount is rendered, and if I check /cart.json before refreshing I see the discount as it should be.

It's just weird, like, no matter what the quantity is in the initial cart state, whenever I change the quantity to 2 the discount is not returned from the section api. It's happening every single time and only at that specific quantity.

As a test, I changed my function so that only one discount is returned in the output array, and changed the discountApplicationStrategy to "FIRST" for this discount - this resolved the issue and the function works at each quantity. However, when implementing a percentage discount instead of fixed, I noticed the same issue at a different price point.

For reference here is the input and output that gives me this behavior. Issue occurs in preview mode as well as with a deployed version.

INPUT

{
  "cart": {
    "cost": {
      "totalAmount": {
        "amount": "1200.0"
      },
      "subtotalAmount": {
        "amount": "1200.0"
      },
      "totalDutyAmount": null,
      "totalTaxAmount": null
    }
  },
  "discountNode": {
    "metafield": {
      "value": {
        "tiers": [
          {
            "value": "10.00",
            "minTotal": "100.00",
            "maxTotal": "-1.00",
            "message": "$10 off"
          },
          {
            "value": "20.00",
            "minTotal": "200.00",
            "maxTotal": "-1.00",
            "message": "$20 off"
          },
          {
            "value": "30.00",
            "minTotal": "300.00",
            "maxTotal": "-1.00",
            "message": "$30 off"
          }
        ]
      }
    }
  }
}

OUTPUT

{
  "discountApplicationStrategy": "MAXIMUM",
  "discounts": [
    {
      "conditions": [
        {
          "orderMinimumSubtotal": {
            "excludedVariantIds": [],
            "minimumAmount": "100",
            "targetType": "ORDER_SUBTOTAL"
          }
        }
      ],
      "message": "$10 off",
      "targets": [
        {
          "orderSubtotal": {
            "excludedVariantIds": []
          }
        }
      ],
      "value": {
        "fixedAmount": {
          "amount": "10"
        }
      }
    },
    {
      "conditions": [
        {
          "orderMinimumSubtotal": {
            "excludedVariantIds": [],
            "minimumAmount": "200",
            "targetType": "ORDER_SUBTOTAL"
          }
        }
      ],
      "message": "$20 off",
      "targets": [
        {
          "orderSubtotal": {
            "excludedVariantIds": []
          }
        }
      ],
      "value": {
        "fixedAmount": {
          "amount": "20"
        }
      }
    },
    {
      "conditions": [
        {
          "orderMinimumSubtotal": {
            "excludedVariantIds": [],
            "minimumAmount": "300",
            "targetType": "ORDER_SUBTOTAL"
          }
        }
      ],
      "message": "$30 off",
      "targets": [
        {
          "orderSubtotal": {
            "excludedVariantIds": []
          }
        }
      ],
      "value": {
        "fixedAmount": {
          "amount": "30"
        }
      }
    }
  ]
}