fix(medusa): keep country_code when partially updating cart addresses (#2683)

**What**
- Fixes a bug where `country_code` was dropped when partially updating a shipping or billing address on a cart.

.changeset/serious-glasses-impress.md

@@ -0,0 +1,5 @@
+---
+"@medusajs/medusa": patch
+---
+
+fix: Fixes a bug where `country_code` was dropped when partially updating a shipping and/or billing address on a cart.

integration-tests/api/__tests__/store/cart/cart.js

@@ -1642,6 +1642,44 @@ describe("/store/carts", () => {
       expect(response.status).toEqual(200)
     })
 
+    it("partially updates shipping and billing address while retaining the addresses country codes", async () => {
+      const api = useApi()
+
+      // Partially update the shipping address
+      await api
+        .post("/store/carts/test-cart", {
+          shipping_address: {
+            last_name: "james",
+          },
+        })
+        .catch((error) => console.log(error))
+
+      // Partially update the billing address
+      const response = await api.post("/store/carts/test-cart", {
+        billing_address: {
+          first_name: "bruce",
+          last_name: "banner",
+          country_code: "us",
+        },
+      })
+
+      expect(response.status).toEqual(200)
+      expect(response.data.cart).toEqual(
+        expect.objectContaining({
+          shipping_address: expect.objectContaining({
+            first_name: "lebron",
+            last_name: "james",
+            country_code: "us",
+          }),
+          billing_address: expect.objectContaining({
+            first_name: "bruce",
+            last_name: "banner",
+            country_code: "us",
+          }),
+        })
+      )
+    })
+
     it("adds free shipping to cart then removes it again", async () => {
       const api = useApi()
 

integration-tests/plugins/__tests__/medusa-plugin-sendgrid/__snapshots__/index.js.snap

@@ -2415,7 +2415,7 @@ Object {
       "address_2": null,
       "city": "ville la something",
       "company": null,
-      "country_code": null,
+      "country_code": "us",
       "created_at": Any<Date>,
       "customer_id": null,
       "deleted_at": null,
@@ -2476,4 +2476,4 @@ Object {
   "tracking_links": Array [],
   "tracking_number": "",
 }
-`;
+`;

packages/medusa/src/services/__tests__/cart.js

@@ -1,12 +1,12 @@
 import _ from "lodash"
 import { MedusaError } from "medusa-core-utils"
 import { IdMap, MockManager, MockRepository } from "medusa-test-utils"
+import { FlagRouter } from "../../utils/flag-router"
 import CartService from "../cart"
 import { InventoryServiceMock } from "../__mocks__/inventory"
 import { LineItemAdjustmentServiceMock } from "../__mocks__/line-item-adjustment"
-import { FlagRouter } from "../../utils/flag-router"
-import { taxProviderServiceMock } from "../__mocks__/tax-provider"
 import { newTotalsServiceMock } from "../__mocks__/new-totals"
+import { taxProviderServiceMock } from "../__mocks__/tax-provider"
 
 const eventBusService = {
   emit: jest.fn(),
@@ -1100,7 +1100,7 @@ describe("CartService", () => {
         last_name: "James",
         address_1: "24 Dunks Drive",
         city: "Los Angeles",
-        country_code: "US",
+        country_code: "us",
         province: "CA",
         postal_code: "93011",
         phone: "+1 (222) 333 4444",

packages/medusa/src/services/cart.ts

@@ -1238,8 +1238,6 @@ class CartService extends TransactionBaseService {
       address = addressOrId as Address
     }
 
-    address.country_code = address.country_code?.toLowerCase() ?? null
-
     if (address.id) {
       cart.billing_address = await addrRepo.save(address)
     } else {
@@ -1284,11 +1282,11 @@ class CartService extends TransactionBaseService {
       address = addressOrId as Address
     }
 
-    address.country_code = address.country_code?.toLowerCase() ?? null
-
     if (
       address.country_code &&
-      !cart.region.countries.find(({ iso_2 }) => address.country_code === iso_2)
+      !cart.region.countries.find(
+        ({ iso_2 }) => address.country_code?.toLowerCase() === iso_2
+      )
     ) {
       throw new MedusaError(
         MedusaError.Types.INVALID_DATA,