From 79582bc94eb420f02ad49a81bcbcc02521e5c414 Mon Sep 17 00:00:00 2001
From: Nicolas Gorga <62995075+NicolasGorga@users.noreply.github.com>
Date: Mon, 24 Nov 2025 05:23:39 -0300
Subject: [PATCH] fix(core-flows): prevent completing cart from webhook when
 order already exists (#14108)

* Prevent completing cart when order already exists in processPaymentWorkflow

* Add tests

* Add changeset
---
 .changeset/plain-windows-end.md               |   5 +
 .../__tests__/cart/store/cart.completion.ts   | 185 ++++++++++++++++++
 .../src/payment/workflows/process-payment.ts  |  19 +-
 3 files changed, 206 insertions(+), 3 deletions(-)
 create mode 100644 .changeset/plain-windows-end.md

diff --git a/.changeset/plain-windows-end.md b/.changeset/plain-windows-end.md
new file mode 100644
index 0000000000..e006dc21b1
--- /dev/null
+++ b/.changeset/plain-windows-end.md
@@ -0,0 +1,5 @@
+---
+"@medusajs/core-flows": patch
+---
+
+fix(core-flows): prevent completing cart from webhook when order already exists
diff --git a/integration-tests/modules/__tests__/cart/store/cart.completion.ts b/integration-tests/modules/__tests__/cart/store/cart.completion.ts
index 98505c8cfc..1f3bf784d9 100644
--- a/integration-tests/modules/__tests__/cart/store/cart.completion.ts
+++ b/integration-tests/modules/__tests__/cart/store/cart.completion.ts
@@ -1,11 +1,14 @@
 import {
   addToCartWorkflow,
+  beginOrderEditOrderWorkflow,
   completeCartWorkflow,
+  confirmOrderEditRequestWorkflow,
   createCartWorkflow,
   createPaymentCollectionForCartWorkflow,
   createPaymentSessionsWorkflow,
   getOrderDetailWorkflow,
   listShippingOptionsForCartWorkflow,
+  orderEditAddNewItemWorkflow,
   processPaymentWorkflow,
 } from "@medusajs/core-flows"
 import { medusaIntegrationTestRunner } from "@medusajs/test-utils"
@@ -26,6 +29,7 @@ import {
 import {
   ContainerRegistrationKeys,
   Modules,
+  PaymentCollectionStatus,
   ProductStatus,
   remoteQueryObjectFromString,
 } from "@medusajs/utils"
@@ -1024,6 +1028,187 @@ medusaIntegrationTestRunner({
             "Failed to do something before ending complete cart workflow"
           )
         })
+
+        it("should avoid completing cart when order already exists", async () => {
+          const salesChannel = await scModuleService.createSalesChannels({
+            name: "Webshop",
+          })
+
+          const location = await stockLocationModule.createStockLocations({
+            name: "Warehouse",
+          })
+
+          const [product] = await productModule.createProducts([
+            {
+              title: "Test product",
+              status: ProductStatus.PUBLISHED,
+              variants: [
+                {
+                  title: "Test variant",
+                  manage_inventory: false,
+                },
+              ],
+            },
+          ])
+
+          const priceSet = await pricingModule.createPriceSets({
+            prices: [
+              {
+                amount: 3000,
+                currency_code: "usd",
+              },
+            ],
+          })
+
+          await pricingModule.createPricePreferences({
+            attribute: "currency_code",
+            value: "usd",
+            has_tax_inclusive: true,
+          })
+
+          await remoteLink.create([
+            {
+              [Modules.PRODUCT]: {
+                variant_id: product.variants[0].id,
+              },
+              [Modules.PRICING]: {
+                price_set_id: priceSet.id,
+              },
+            },
+            {
+              [Modules.SALES_CHANNEL]: {
+                sales_channel_id: salesChannel.id,
+              },
+              [Modules.STOCK_LOCATION]: {
+                stock_location_id: location.id,
+              },
+            },
+          ])
+
+          // create cart
+          const cart = await cartModuleService.createCarts({
+            currency_code: "usd",
+            sales_channel_id: salesChannel.id,
+          })
+
+          await addToCartWorkflow(appContainer).run({
+            input: {
+              items: [
+                {
+                  variant_id: product.variants[0].id,
+                  quantity: 1,
+                  requires_shipping: false,
+                },
+              ],
+              cart_id: cart.id,
+            },
+          })
+
+          await createPaymentCollectionForCartWorkflow(appContainer).run({
+            input: {
+              cart_id: cart.id,
+            },
+          })
+
+          const [payCol] = await remoteQuery(
+            remoteQueryObjectFromString({
+              entryPoint: "cart_payment_collection",
+              variables: { filters: { cart_id: cart.id } },
+              fields: ["payment_collection_id"],
+            })
+          )
+
+          await createPaymentSessionsWorkflow(appContainer).run({
+            input: {
+              payment_collection_id: payCol.payment_collection_id,
+              provider_id: "pp_system_default",
+              context: {},
+              data: {},
+            },
+          })
+
+          const {
+            result: { id: orderId },
+          } = await completeCartWorkflow(appContainer).run({
+            input: {
+              id: cart.id,
+            },
+          })
+
+          await beginOrderEditOrderWorkflow(appContainer).run({
+            input: {
+              order_id: orderId,
+            },
+          })
+          await orderEditAddNewItemWorkflow(appContainer).run({
+            input: {
+              order_id: orderId,
+              items: [
+                {
+                  variant_id: product.variants[0].id,
+                  quantity: 1,
+                },
+              ],
+            },
+          })
+          await confirmOrderEditRequestWorkflow(appContainer).run({
+            input: { order_id: orderId },
+          })
+
+          const orderPaymentCollections = await remoteQuery(
+            remoteQueryObjectFromString({
+              entryPoint: "order_payment_collection",
+              variables: { filters: { order_id: orderId } },
+              fields: ["payment_collection_id"],
+            })
+          )
+
+          const [pendingPaymentCollection] = await remoteQuery(
+            remoteQueryObjectFromString({
+              entryPoint: "payment_collection",
+              variables: {
+                filters: {
+                  id: orderPaymentCollections.map(
+                    (orderPayCol) => orderPayCol.payment_collection_id
+                  ),
+                  status: PaymentCollectionStatus.NOT_PAID,
+                },
+              },
+              fields: ["id"],
+            })
+          )
+
+          const { result: paymentSession } =
+            await createPaymentSessionsWorkflow(appContainer).run({
+              input: {
+                payment_collection_id: pendingPaymentCollection.id,
+                provider_id: "pp_system_default",
+                context: {},
+                data: {},
+              },
+            })
+
+          let completeCartCalled = false
+          const workflow = processPaymentWorkflow(appContainer)
+
+          workflow.addAction("track-complete-cart-step", {
+            invoke: async function trackStep({ invoke }) {
+              completeCartCalled = !!invoke["complete-cart-after-payment-step"]
+            },
+          })
+
+          await workflow.run({
+            input: {
+              action: "captured",
+              data: {
+                session_id: paymentSession.id,
+                amount: 3000,
+              },
+            },
+          })
+
+          expect(completeCartCalled).toBe(false)
+        })
       })
     })
   },
diff --git a/packages/core/core-flows/src/payment/workflows/process-payment.ts b/packages/core/core-flows/src/payment/workflows/process-payment.ts
index 9210cfa468..bf219042af 100644
--- a/packages/core/core-flows/src/payment/workflows/process-payment.ts
+++ b/packages/core/core-flows/src/payment/workflows/process-payment.ts
@@ -73,10 +73,23 @@ export const processPaymentWorkflow = createWorkflow(
     const cartId = transform(
       { cartPaymentCollection },
       ({ cartPaymentCollection }) => {
-        return cartPaymentCollection.data[0].cart_id
+        return cartPaymentCollection.data[0]?.cart_id
       }
     )
 
+    const { data: order } = useQueryGraphStep({
+        entity: "order_cart",
+        fields: ["id"],
+        filters: {
+          cart_id: cartId
+        },
+        options: {
+            isList: false
+        }
+      }).config({
+        name: "cart-order-query",
+      })
+
     when("lock-cart-when-available", { cartId }, ({ cartId }) => {
       return !!cartId
     }).then(() => {
@@ -158,8 +171,8 @@ export const processPaymentWorkflow = createWorkflow(
       })
     })
 
-    when({ cartPaymentCollection }, ({ cartPaymentCollection }) => {
-      return !!cartPaymentCollection.data.length
+    when({ cartPaymentCollection, order }, ({ cartPaymentCollection, order }) => {
+      return !!cartPaymentCollection.data.length && !order
     }).then(() => {
       completeCartAfterPaymentStep({
         cart_id: cartPaymentCollection.data[0].cart_id,