fix(product): options validation if ids are same (#9622)

**What**
- fix validation of existing variant with options on update if the ids are same

---

FIXES CC-60
CLOSES https://github.com/medusajs/medusa/issues/9620

packages/modules/product/integration-tests/__tests__/product-module-service/products.spec.ts

@@ -300,6 +300,169 @@ moduleIntegrationTestRunner<IProductModuleService>({
           )
         })
 
+        it("should upsert variants (update one and create one)", async () => {
+          let [product] = await service.createProducts([
+            {
+              title: "New product",
+              description: "New description",
+              options: [
+                { title: "size", values: ["x", "l"] },
+                { title: "color", values: ["red", "green"] },
+              ],
+              variants: [
+                {
+                  title: "new variant 1",
+                  options: { size: "l", color: "red" },
+                },
+                {
+                  title: "new variant 2",
+                  options: { size: "l", color: "green" },
+                },
+              ],
+            },
+          ])
+
+          product = await service.retrieveProduct(product.id, {
+            relations: [
+              "options",
+              "options.values",
+              "variants",
+              "variants.options",
+            ],
+          })
+
+          expect(product).toEqual(
+            expect.objectContaining({
+              title: "New product",
+              description: "New description",
+              options: expect.arrayContaining([
+                expect.objectContaining({
+                  title: "size",
+                  values: expect.arrayContaining([
+                    expect.objectContaining({
+                      value: "x",
+                    }),
+                    expect.objectContaining({
+                      value: "l",
+                    }),
+                  ]),
+                }),
+                expect.objectContaining({
+                  title: "color",
+                  values: expect.arrayContaining([
+                    expect.objectContaining({
+                      value: "red",
+                    }),
+                    expect.objectContaining({
+                      value: "green",
+                    }),
+                  ]),
+                }),
+              ]),
+              variants: expect.arrayContaining([
+                expect.objectContaining({
+                  title: "new variant 1",
+                  options: expect.arrayContaining([
+                    expect.objectContaining({
+                      value: "l",
+                    }),
+                    expect.objectContaining({
+                      value: "red",
+                    }),
+                  ]),
+                }),
+                expect.objectContaining({
+                  title: "new variant 2",
+                  options: expect.arrayContaining([
+                    expect.objectContaining({
+                      value: "l",
+                    }),
+                    expect.objectContaining({
+                      value: "green",
+                    }),
+                  ]),
+                }),
+              ]),
+            })
+          )
+
+          const existingVariant1 = product.variants.find(
+            (v) => v.title === "new variant 1"
+          )
+
+          const existingVariant2 = product.variants.find(
+            (v) => v.title === "new variant 2"
+          )
+
+          await service.upsertProductVariants([
+            {
+              id: existingVariant1.id,
+              product_id: product.id,
+              title: "updated variant 1",
+              options: { size: "x", color: "red" }, // update options
+            },
+            {
+              id: existingVariant2.id,
+              title: "new variant 2",
+              options: { size: "l", color: "green" }, // just preserve old one
+            },
+            {
+              product_id: product.id,
+              title: "created variant 3",
+              options: { size: "x", color: "green" }, // create a new variant
+            },
+          ])
+
+          product = await service.retrieveProduct(product.id, {
+            relations: [
+              "options",
+              "options.values",
+              "variants",
+              "variants.options",
+            ],
+          })
+
+          expect(product.variants).toEqual(
+            expect.arrayContaining([
+              expect.objectContaining({
+                id: existingVariant1.id,
+                title: "updated variant 1",
+                options: expect.arrayContaining([
+                  expect.objectContaining({
+                    value: "x",
+                  }),
+                  expect.objectContaining({
+                    value: "red",
+                  }),
+                ]),
+              }),
+              expect.objectContaining({
+                id: existingVariant2.id,
+                title: "new variant 2",
+                options: expect.arrayContaining([
+                  expect.objectContaining({
+                    value: "l",
+                  }),
+                  expect.objectContaining({
+                    value: "green",
+                  }),
+                ]),
+              }),
+              expect.objectContaining({
+                title: "created variant 3",
+                options: expect.arrayContaining([
+                  expect.objectContaining({
+                    value: "x",
+                  }),
+                  expect.objectContaining({
+                    value: "green",
+                  }),
+                ]),
+              }),
+            ])
+          )
+        })
+
         it("should preserve option and value identity on update", async () => {
           const productBefore = await service.retrieveProduct(productTwo.id, {
             relations: [

packages/modules/product/src/services/product-module-service.ts

@@ -380,10 +380,12 @@ export default class ProductModuleService
         productOptions
       )
 
-    ProductModuleService.checkIfVariantWithOptionsAlreadyExists(
+    if (data.some((d) => !!d.options)) {
-      productVariantsWithOptions as any,
+      ProductModuleService.checkIfVariantWithOptionsAlreadyExists(
-      allVariants
+        productVariantsWithOptions as any,
-    )
+        allVariants
+      )
+    }
 
     const { entities: productVariants, performedActions } =
       await this.productVariantService_.upsertWithReplace(
@@ -1819,7 +1821,7 @@ export default class ProductModuleService
   protected static checkIfVariantWithOptionsAlreadyExists(
     data: ((
       | ProductTypes.CreateProductVariantDTO
-      | ProductTypes.UpdateProductVariantDTO
+      | UpdateProductVariantInput
     ) & { options: { id: string }[]; product_id: string })[],
     variants: ProductVariant[]
   ) {
@@ -1832,6 +1834,10 @@ export default class ProductModuleService
           return false
         }
 
+        if ((variantData as UpdateProductVariantInput)?.id === v.id) {
+          return false
+        }
+
         return (variantData.options as unknown as { id: string }[])!.every(
           (optionValue) => {
             const variantOptionValue = v.options.find(