fix: skip promotion usage limit checks on edit flows (medusajs#14176)

* fix: skip promotion usage limit checks on edit flows

* feat: add test check

Author: fPolic

.changeset/nice-kids-beg.md

@@ -0,0 +1,7 @@
+---
+"@medusajs/promotion": patch
+"@medusajs/core-flows": patch
+"@medusajs/types": patch
+---
+
+fix: skip promotion usage limit checks on edit flows

integration-tests/http/__tests__/exchanges/exchanges.spec.ts

@@ -1437,6 +1437,16 @@ medusaIntegrationTestRunner({
             adminHeaders
           )
 
+          const promotionModule = getContainer().resolve(Modules.PROMOTION)
+
+          // check that adjustments are computed for promotions that exceeded usage limit (we ignore usage limits on edit flows)
+          // @ts-ignore
+          await promotionModule.updatePromotions({
+            id: appliedPromotion.id,
+            limit: 1,
+            used: 1,
+          })
+
           let result = await api.post(
             "/admin/exchanges",
             {

packages/core/core-flows/src/order/workflows/compute-adjustments-for-preview.ts

@@ -29,7 +29,7 @@ export type ComputeAdjustmentsForPreviewWorkflowInput = {
   /**
    * The order's details.
    */
-  order: OrderDTO & { 
+  order: OrderDTO & {
     /**
      * The promotions applied to the order.
      */
@@ -52,7 +52,7 @@ export const computeAdjustmentsForPreviewWorkflowId =
  *
  * You can use this workflow within your customizations or your own custom workflows, allowing you to compute adjustments
  * in your custom flows.
- * 
+ *
  * @since v2.12.0
  *
  * @example
@@ -110,6 +110,9 @@ export const computeAdjustmentsForPreviewWorkflow = createWorkflow(
       const actions = getActionsToComputeFromPromotionsStep({
         computeActionContext: actionsToComputeItemsInput,
         promotionCodesToApply: orderPromotions,
+        options: {
+          skip_usage_limit_checks: true,
+        },
       })
 
       const { lineItemAdjustmentsToCreate } =

packages/core/types/src/promotion/common/compute-actions.ts

@@ -295,4 +295,11 @@ export interface ComputeActionOptions {
    * automatically. If not provided, the automatic promotions are applied.
    */
   prevent_auto_promotions?: boolean
+
+  /**
+   * Whether to skip the usage limit checks.
+   * Useful when recomputing adjustment for promotions that are already applied as a part of edit/exchange flows.
+   *
+   */
+  skip_usage_limit_checks?: boolean
 }

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

@@ -634,7 +634,10 @@ export default class PromotionModuleService
     options: PromotionTypes.ComputeActionOptions = {},
     @MedusaContext() sharedContext: Context = {}
   ): Promise<PromotionTypes.ComputeActions[]> {
-    const { prevent_auto_promotions: preventAutoPromotions } = options
+    const {
+      prevent_auto_promotions: preventAutoPromotions,
+      skip_usage_limit_checks: skipUsageLimitChecks,
+    } = options
     const computedActions: PromotionTypes.ComputeActions[] = []
     const { items = [], shipping_methods: shippingMethods = [] } =
       applicationContext
@@ -806,6 +809,7 @@ export default class PromotionModuleService
       } = promotion
 
       if (
+        !skipUsageLimitChecks &&
         promotion.campaign?.budget?.type === CampaignBudgetType.USE_BY_ATTRIBUTE
       ) {
         const attribute = promotion.campaign?.budget?.attribute!
@@ -847,7 +851,7 @@ export default class PromotionModuleService
       }
 
       // Check promotion usage limit
-      if (typeof promotion.limit === "number") {
+      if (!skipUsageLimitChecks && typeof promotion.limit === "number") {
         if ((promotion.used ?? 0) >= promotion.limit) {
           computedActions.push({
             action: ComputedActions.PROMOTION_LIMIT_EXCEEDED,