Fix for assigning promotion-delivery to the order.

Author: Xziy

models/Order.js

@@ -1308,13 +1308,15 @@ let Model = {
                 order.promotionCode = order.promotionCode.id;
             }
             // Calculate delivery costs
-            let delivery = {}; // for self service
+            let delivery = {};
             let softDeliveryCalculation = null;
             if (order.selfService === false) {
+                // The SOFT_DELIVERY_CALCULATION setting disables strict checking of the delivery address.
                 softDeliveryCalculation = await Settings.get("SOFT_DELIVERY_CALCULATION");
                 emitter.emit("core:count-before-delivery-cost", order);
+                // order.promotionDelivery is preferred over the delivery setting
                 if (order.promotionDelivery && isValidDelivery(order.promotionDelivery)) {
-                    order.delivery = order.promotionDelivery;
+                    delivery = order.promotionDelivery;
                 }
                 else {
                     let deliveryAdapter = await Adapter.getDeliveryAdapter();
@@ -1337,6 +1339,7 @@ let Model = {
                         }
                     }
                 }
+                // Case when the shipping cost cannot be calculated
                 if (softDeliveryCalculation &&
                     (!order.delivery ||
                         Object.keys(order.delivery).length === 0 ||

models/Order.ts

@@ -1577,14 +1577,17 @@ let Model = {
       }
 
       // Calculate delivery costs
-      let delivery = {} as Delivery  // for self service
+      let delivery = {} as Delivery
       let softDeliveryCalculation = null;
       if(order.selfService === false) {
-        
+      
+        // The SOFT_DELIVERY_CALCULATION setting disables strict checking of the delivery address.
         softDeliveryCalculation = await Settings.get("SOFT_DELIVERY_CALCULATION")
         emitter.emit("core:count-before-delivery-cost", order);
+
+        // order.promotionDelivery is preferred over the delivery setting
         if (order.promotionDelivery && isValidDelivery(order.promotionDelivery)) {
-          order.delivery = order.promotionDelivery;
+          delivery = order.promotionDelivery;
         } else {
           let deliveryAdapter = await Adapter.getDeliveryAdapter();
           await deliveryAdapter.reset(order);
@@ -1606,6 +1609,8 @@ let Model = {
           }
         }
 
+
+        // Case when the shipping cost cannot be calculated
         if (
           softDeliveryCalculation && 
           (!order.delivery ||