fix(pricing): Calculate price sets with amount 0 (#8622)

packages/modules/pricing/integration-tests/__tests__/services/pricing-module/calculate-price.spec.ts

@@ -897,6 +897,61 @@ moduleIntegrationTestRunner<IPricingModuleService>({
           ])
         })
 
+        it("should return a price of 0", async () => {
+          const priceSet = await service.createPriceSets({
+            prices: [
+              {
+                amount: 0,
+                currency_code: "USD",
+              },
+            ],
+          })
+
+          const priceSetsResult = await service.calculatePrices(
+            { id: [priceSet.id] },
+            {
+              context: {
+                currency_code: "USD",
+              },
+            }
+          )
+
+          expect(priceSetsResult).toEqual([
+            {
+              id: priceSet.id,
+              is_calculated_price_price_list: false,
+              is_calculated_price_tax_inclusive: false,
+              calculated_amount: 0,
+              raw_calculated_amount: {
+                value: "0",
+                precision: 20,
+              },
+              is_original_price_price_list: false,
+              is_original_price_tax_inclusive: false,
+              original_amount: 0,
+              raw_original_amount: {
+                value: "0",
+                precision: 20,
+              },
+              currency_code: "USD",
+              calculated_price: {
+                id: expect.any(String),
+                price_list_id: null,
+                price_list_type: null,
+                min_quantity: null,
+                max_quantity: null,
+              },
+              original_price: {
+                id: expect.any(String),
+                price_list_id: null,
+                price_list_type: null,
+                min_quantity: null,
+                max_quantity: null,
+              },
+            },
+          ])
+        })
+
         describe("Price Lists", () => {
           it("should return price list prices when price list conditions match", async () => {
             await createPriceLists(service)

packages/modules/pricing/src/services/pricing-module.ts

@@ -272,6 +272,7 @@ export default class PricingModuleService
           defaultPrice
         let originalPrice: PricingTypes.CalculatedPriceSetDTO | undefined =
           defaultPrice
+
         if (priceListPrice) {
           calculatedPrice = priceListPrice
 
@@ -338,8 +339,9 @@ export default class PricingModuleService
               calculatedPrice.currency_code!,
               pricingContext.context?.region_id as string
             ),
-            calculated_amount:
-              parseFloat((calculatedPrice?.amount as string) || "") || null,
+            calculated_amount: isPresent(calculatedPrice?.amount)
+              ? parseFloat(calculatedPrice?.amount as string)
+              : null,
             raw_calculated_amount: calculatedPrice?.raw_amount || null,
 
             is_original_price_price_list: !!originalPrice?.price_list_id,
@@ -351,8 +353,9 @@ export default class PricingModuleService
                   pricingContext.context?.region_id as string
                 )
               : false,
-            original_amount:
-              parseFloat((originalPrice?.amount as string) || "") || null,
+            original_amount: isPresent(originalPrice?.amount)
+              ? parseFloat(originalPrice?.amount as string)
+              : null,
             raw_original_amount: originalPrice?.raw_amount || null,
 
             currency_code: calculatedPrice?.currency_code || null,