Extract order cleanup and total recalculation

Also removes the now-unnecessary `PersistDiscountedOrder` class.

Author: mamhoff

promotions/app/models/solidus_promotions/order_adjuster.rb

@@ -20,10 +20,9 @@ def call
 
       DiscountOrder.new(order, promotions, dry_run: dry_run).call
 
-      unless dry_run
-        order.save!
-      end
-      order
+      CleanDiscountedOrder.new(order).call
+
+      RecalculatePromoTotals.new(order).call
     end
   end
 end

promotions/app/models/solidus_promotions/order_adjuster/clean_discounted_order.rb

@@ -0,0 +1,28 @@
+# frozen_string_literal: true
+
+module SolidusPromotions
+  class OrderAdjuster
+    class CleanDiscountedOrder
+      attr_reader :order
+
+      def initialize(order)
+        @order = order
+      end
+
+      def call
+        order.line_items.each do |line_item|
+          line_item.adjustments.select { _1.amount.zero? }.each(&:mark_for_destruction)
+        end
+
+        order.shipments.each do |shipment|
+          shipment.adjustments.select { _1.amount.zero? }.each(&:mark_for_destruction)
+          shipment.shipping_rates.each do |shipping_rate|
+            shipping_rate.discounts.select { _1.amount.zero? }.each(&:mark_for_destruction)
+          end
+        end
+
+        order
+      end
+    end
+  end
+end

promotions/app/models/solidus_promotions/order_adjuster/discount_order.rb

@@ -25,23 +25,6 @@ def call
           end
         end
 
-        order.line_items.each do |line_item|
-          line_item.adjustments.select { _1.amount.zero? }.each(&:mark_for_destruction)
-          line_item.promo_total = line_item.adjustments.reject(&:marked_for_destruction?).sum(&:amount)
-          line_item.adjustment_total = line_item.promo_total
-        end
-
-        order.shipments.each do |shipment|
-          shipment.adjustments.select { _1.amount.zero? }.each(&:mark_for_destruction)
-          shipment.promo_total = shipment.adjustments.reject(&:marked_for_destruction?).sum(&:amount)
-          shipment.adjustment_total = shipment.promo_total
-        end
-
-        order.item_total = order.line_items.sum(&:amount)
-        order.item_count = order.line_items.sum(&:quantity)
-        order.promo_total = (order.line_items + order.shipments).sum(&:promo_total)
-        order.adjustment_total = order.promo_total
-
         order
       end
 
@@ -81,7 +64,6 @@ def adjust_shipments(benefits)
       def adjust_shipping_rates(benefits)
         order.shipments.flat_map(&:shipping_rates).filter_map do |rate|
           next unless rate.cost
-
           discounts = generate_discounts(benefits, rate)
           chosen_discounts = SolidusPromotions.config.discount_chooser_class.new(discounts).call
           (rate.current_discounts - chosen_discounts).each(&:mark_for_destruction)

promotions/app/models/solidus_promotions/order_adjuster/persist_discounted_order.rb

@@ -0,0 +1,39 @@
+# frozen_string_literal: true
+
+module SolidusPromotions
+  class OrderAdjuster
+    class RecalculatePromoTotals
+      attr_reader :order
+
+      def initialize(order)
+        @order = order
+      end
+
+      def call
+        order.line_items.each do |line_item|
+          line_item.promo_total = calculate_promo_total_for_adjustable(line_item)
+        end
+
+        order.shipments.each do |shipment|
+          shipment.promo_total = calculate_promo_total_for_adjustable(shipment)
+        end
+
+        order.item_total = order.line_items.sum(&:amount)
+        order.item_count = order.line_items.sum(&:quantity)
+        order.promo_total = (order.line_items + order.shipments).sum(&:promo_total)
+
+        order
+      end
+
+      private
+
+      def calculate_promo_total_for_adjustable(adjustable)
+        adjustable
+          .adjustments
+          .select(&:promotion?)
+          .reject(&:marked_for_destruction?)
+          .sum(&:amount)
+      end
+    end
+  end
+end

promotions/app/models/solidus_promotions/order_adjuster/recalculate_promo_totals.rb

@@ -42,7 +42,9 @@
         it "creates a new discounted line item" do
           expect(order.adjustments).to be_empty
           expect(order.line_items.count).to eq(3)
+          # 19.99 * 2
           expect(order.total).to eq(39.98)
+          # 19.99 * 2 + 4 * 1
           expect(order.item_total).to eq(43.98)
           expect(order.item_total_before_tax).to eq(39.98)
           expect(order.line_items.flat_map(&:adjustments).length).to eq(1)
@@ -56,6 +58,7 @@
           it "creates a new discounted line item" do
             expect(order.adjustments).to be_empty
             expect(order.line_items.count).to eq(3)
+            # 19.99 * 3
             expect(order.total).to eq(59.97)
             expect(order.item_total).to eq(67.97)
             expect(order.item_total_before_tax).to eq(59.97)

promotions/spec/models/promotion/integration_spec.rb

@@ -67,6 +67,7 @@
         it " will not create the adjustment" do
           expect {
             subject
+            order.save!
           }.not_to change { adjustable.adjustments.length }
         end
       end
@@ -83,6 +84,7 @@
         it "doesn't create an adjustment" do
           expect {
             subject
+            order.save!
           }.to change { adjustable.adjustments.length }.by(0)
         end
 
@@ -94,6 +96,7 @@
             adjustable.reload
             expect {
               subject
+              order.save!
             }.to change { adjustable.reload.adjustments.length }.by(-1)
           end
         end
@@ -158,6 +161,7 @@
       it "will not create an adjustment on the shipping rate" do
         expect do
           subject
+          order.save!
         end.not_to change { order.shipments.first.shipping_rates.first.discounts.count }
       end
     end
@@ -173,6 +177,7 @@
       expect do
         promotion
         subject.call
+        order.save!
       end.to change { order.shipments.first.adjustments.count }
     end
 
@@ -184,6 +189,7 @@
         expect do
           promotion
           subject.call
+          order.save!
         end.not_to change { order.shipments.first.adjustments.count }
       end
     end