fix(core-flows): Avoid throwing if no prices found for variant when adding to cart custom price item (#14528)

* Avoid throwing prices not found error when line item is custom unit price

* Add changeset

* Avoid throwing upo variant price validation for custom priced item variants

.changeset/pretty-planes-switch.md

@@ -0,0 +1,5 @@
+---
+"@medusajs/core-flows": patch
+---
+
+fix(core-flows): Avoid throwing if no prices found for variant when adding to cart custom price item

integration-tests/modules/__tests__/cart/store/cart.workflows.spec.ts

@@ -2474,6 +2474,103 @@ medusaIntegrationTestRunner({
           ])
         })
 
+        it("should add item to cart with unit_price when variant has no price set", async () => {
+          const salesChannel = await scModuleService.createSalesChannels({
+            name: "Webshop",
+          })
+
+          const location = await stockLocationModule.createStockLocations({
+            name: "Warehouse",
+          })
+
+          let cart = await cartModuleService.createCarts({
+            currency_code: "usd",
+            sales_channel_id: salesChannel.id,
+          })
+
+          const [product] = await productModule.createProducts([
+            {
+              title: "Test product",
+              status: ProductStatus.PUBLISHED,
+              variants: [
+                {
+                  title: "Test variant",
+                },
+              ],
+            },
+          ])
+
+          const inventoryItem = await inventoryModule.createInventoryItems({
+            sku: "inv-1234",
+          })
+
+          await inventoryModule.createInventoryLevels([
+            {
+              inventory_item_id: inventoryItem.id,
+              location_id: location.id,
+              stocked_quantity: 2,
+              reserved_quantity: 0,
+            },
+          ])
+
+          await remoteLink.create([
+            {
+              [Modules.SALES_CHANNEL]: {
+                sales_channel_id: salesChannel.id,
+              },
+              [Modules.STOCK_LOCATION]: {
+                stock_location_id: location.id,
+              },
+            },
+            {
+              [Modules.PRODUCT]: {
+                variant_id: product.variants[0].id,
+              },
+              [Modules.INVENTORY]: {
+                inventory_item_id: inventoryItem.id,
+              },
+            },
+          ])
+
+          cart = await cartModuleService.retrieveCart(cart.id, {
+            select: ["id", "region_id", "currency_code", "sales_channel_id"],
+          })
+
+          // Add item with unit_price specified even though variant has no price set
+          await addToCartWorkflow(appContainer).run({
+            input: {
+              items: [
+                {
+                  variant_id: product.variants[0].id,
+                  quantity: 1,
+                  unit_price: 5000,
+                },
+              ],
+              cart_id: cart.id,
+            },
+          })
+
+          cart = await cartModuleService.retrieveCart(cart.id, {
+            relations: ["items"],
+          })
+
+          expect(cart).toEqual(
+            expect.objectContaining({
+              id: cart.id,
+              currency_code: "usd",
+              items: expect.arrayContaining([
+                expect.objectContaining({
+                  unit_price: 5000,
+                  is_custom_price: true,
+                  quantity: 1,
+                  title: "Test product",
+                  subtitle: "Test variant",
+                }),
+              ]),
+            })
+          )
+        })
+
         describe("setPricingContext hook", () => {
           it("should use context provided by the hook", async () => {
             const salesChannel = await scModuleService.createSalesChannels({

packages/core/core-flows/src/cart/steps/get-variant-price-sets.ts

@@ -91,13 +91,15 @@ async function fetchVariantPriceSets(
 }
 
 /**
- * Validates that all variants have price sets and throws error for missing ones
+ * Validates that all variants without a custom price have price sets and throws error for missing ones
  */
 function validateVariantPriceSets(
-  variantPriceSets: VariantPriceSetData[]
+  variantPriceSets: VariantPriceSetData[],
+  variantsWithCustomPrice: string[] = []
 ): void {
+  const variantsWithCustomPriceSet = new Set(variantsWithCustomPrice)
   const notFound = variantPriceSets
-    .filter((v) => !v.price_set?.id)
+    .filter((v) => !v.price_set?.id && !variantsWithCustomPriceSet.has(v.id))
     .map((v) => v.id)
 
   if (notFound.length) {
@@ -287,7 +289,10 @@ export const getVariantPriceSetsStep = createStep(
       const variantIds = bulkData.map((item) => item.variantId)
       const variantPriceSets = await fetchVariantPriceSets(query, variantIds)
 
-      validateVariantPriceSets(variantPriceSets)
+      const variantsWithCustomPrice = bulkData
+        .filter((item) => !!item.context?.is_custom_price)
+        .map((item) => item.variantId)
+      validateVariantPriceSets(variantPriceSets, variantsWithCustomPrice)
 
       // Map variant IDs to price set IDs
       const variantToPriceSetId = new Map<string, string>()

packages/core/core-flows/src/cart/workflows/get-variants-and-items-with-prices.ts

@@ -125,6 +125,7 @@ export const getVariantsAndItemsWithPrices = createWorkflow(
               context: {
                 ...baseContext,
                 quantity: item.quantity,
+                is_custom_price: !!item.unit_price,
               },
             }
           })
@@ -180,7 +181,10 @@ export const getVariantsAndItemsWithPrices = createWorkflow(
             calculatedPriceSet = calculatedPriceSets[item_.variant_id!]
           }
 
-          if (!calculatedPriceSet && item_.variant_id) {
+          const isCustomPrice =
+            item_.is_custom_price ?? isDefined(item?.unit_price)
+
+          if (!calculatedPriceSet && item_.variant_id && !isCustomPrice) {
             priceNotFound.push(item_.variant_id)
           }
 
@@ -198,9 +202,6 @@ export const getVariantsAndItemsWithPrices = createWorkflow(
             variant.calculated_price = calculatedPriceSet
           }
 
-          const isCustomPrice =
-            item_.is_custom_price ?? isDefined(item?.unit_price)
-
           const input: PrepareLineItemDataInput = {
             item: item_,
             variant: variant,