Mark adjustments for destruction instead of destroying

See code comments and spec changes. This is similar to how we handled
this in the legacy promotion system.

Co-authored-by: Adam <adam@super.gd>
Co-authored-by: Alistair <alistair@super.gd>
Co-authored-by: An <andrew@super.gd>
Co-authored-by: Benjamin <benjamin@super.gd>
Co-authored-by: Harmony <harmony@super.gd>
Co-authored-by: Jared <jared@super.gd>
Co-authored-by: Nick <nick@super.gd>
Co-authored-by: Senem <senem@super.gd>
Co-authored-by: Sofia <sofia@super.g

Author: 9 people

promotions/app/models/solidus_promotions/order_adjuster.rb

@@ -19,7 +19,6 @@ def call(persist: true)
       # TODO: - enemy identified
       discounted_order = DiscountOrder.new(order, promotions, dry_run: dry_run).call
 
-      # TODO: - enemy identified
       PersistDiscountedOrder.new(discounted_order).call unless dry_run
 
       order.reset_current_discounts

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

@@ -34,13 +34,14 @@ def call
 
       attr_reader :order
 
-      # Walk through the discounts for an item and update adjustments for it. Once
-      # all of the discounts have been added as adjustments, remove any old promotion
-      # adjustments that weren't touched.
+      # Walk through the discounts for an item and update adjustments for it.
+      # Once all of the discounts have been added as adjustments, mark for
+      # destruction any old promotion adjustments that weren't touched.
       #
       # @private
       # @param [#adjustments] item a {Spree::LineItem} or {Spree::Shipment}
-      # @param [Array<SolidusPromotions::ItemDiscount>] item_discounts a list of calculated discounts for an item
+      # @param [Array<SolidusPromotions::ItemDiscount>] item_discounts a list of
+      #   calculated discounts for an item
       # @return [void]
       def update_adjustments(item, item_discounts)
         promotion_adjustments = item.adjustments.select(&:promotion?)
@@ -52,7 +53,7 @@ def update_adjustments(item, item_discounts)
         # Remove any promotion adjustments tied to promotion benefits which no longer match.
         unmatched_adjustments = promotion_adjustments - active_adjustments
 
-        item.adjustments.destroy(unmatched_adjustments)
+        unmatched_adjustments.each(&:mark_for_destruction)
       end
 
       # Update or build a new promotion adjustment on an item.

promotions/spec/models/solidus_promotions/order_adjuster_spec.rb

@@ -132,11 +132,12 @@
           let(:old_promotion_benefit) { create(:promotion, :with_adjustable_action, apply_automatically: false).actions.first }
           let!(:adjustment) { create(:adjustment, source: old_promotion_benefit, adjustable: line_item) }
 
-          it "removes the old adjustment from the line item" do
+          it "marks the old adjustment for destruction" do
             adjustable.reload
             expect {
               subject
-            }.to change { adjustable.reload.adjustments.length }.by(-1)
+            }.to change { adjustable.adjustments.first.marked_for_destruction? }
+              .from(false).to(true)
           end
         end
       end