Merge pull request #3364 from feitianbubu/fix/promo-clear-expiry

fix(promo): allow clearing promo code expiry on edit

backend/internal/handler/admin/promo_handler.go

@@ -148,7 +148,7 @@ func (h *PromoHandler) Update(c *gin.Context) {
 	if req.ExpiresAt != nil {
 		if *req.ExpiresAt == 0 {
 			// 0 表示清除过期时间
-			input.ExpiresAt = nil
+			input.ExpiresAt = &time.Time{}
 		} else {
 			t := time.Unix(*req.ExpiresAt, 0)
 			input.ExpiresAt = &t

backend/internal/service/promo_service.go

@@ -236,6 +236,9 @@ func (s *PromoService) Update(ctx context.Context, id int64, input *UpdatePromoC
 		promoCode.Status = *input.Status
 	}
 	if input.ExpiresAt != nil {
+		if input.ExpiresAt.IsZero() {
+			input.ExpiresAt = nil
+		}
 		promoCode.ExpiresAt = input.ExpiresAt
 	}
 	if input.Notes != nil {