“What is the X-ray telling me?”

One row per layer, always in this order: product prices, product discounts, order discounts, shipping, tax and the total. Every bar is drawn on one scale, from zero to the product prices, so you can see how much each layer takes.

• A solid bar is a price; a hatched bar is money taken off.
• A dashed outline with a crack is a discount that wasn’t applied, drawn where it would have landed.
• A short tick is a layer that added nothing; the white bar is the total.
• On a changed test cart, a discount that’s new since the expected result is drawn in blue hatching.

Under it, “Price, layer by layer” has the same numbers as a table, then the lines (price, discount, line total) and the applied discounts, each with where it comes from: a code, automatic, or the app’s name.

Codes you entered, and discounts the cart nearly got or lost to another one, get a banner: “SUMMER20 wasn’t applied”, the sentence saying why, what checkout tells the customer, and links to open the discounts in Shopify. When two discounts clash, the banner adds the total with each one alone. The rest (not active, no qualifying items, an app’s own logic, not for guests) are listed under “Other discounts not applied”.

Every reason, with the sentence the app writes for it.

• Shipping options are listed as checkout shows them. A rate a delivery customization hides is marked “Hidden at checkout”.
• A free rate with a minimum says how far the cart is: “Free from $70.00; this cart is $50.10 short”.
• When no rate reaches the address, the cart can’t be bought: the X-ray says so, and the banner says why.
• Lines over the stock get a warning with what’s available; checkout sells only what’s in stock.