[v4.6] Fix return item initialization in backend

backend/app/controllers/spree/admin/return_authorizations_controller.rb

@@ -40,10 +40,13 @@ def load_return_items
         associated_inventory_units = @return_authorization.return_items.map(&:inventory_unit)
         unassociated_inventory_units = all_inventory_units - associated_inventory_units
 
-        new_return_items = unassociated_inventory_units.map do |new_unit|
-          Spree::ReturnItem.new(inventory_unit: new_unit).tap(&:set_default_amount)
+        unassociated_inventory_units.each do |new_unit|
+          @return_authorization.return_items.
+            build(inventory_unit: new_unit).
+            tap(&:set_default_amount)
         end
-        @form_return_items = (@return_authorization.return_items + new_return_items).sort_by(&:inventory_unit_id)
+
+        @form_return_items = @return_authorization.return_items.sort_by(&:inventory_unit_id)
       end
 
       def load_reimbursement_types

backend/spec/controllers/spree/admin/return_authorizations_controller_spec.rb

@@ -102,6 +102,19 @@
           expect(assigns(:form_return_items).size).to eq 3
           expect(assigns(:form_return_items).select(&:new_record?).size).to eq 3
         end
+
+        context 'with an order with currency other than the store default' do
+          let!(:order) { create(:shipped_order, line_items_count: 3, currency: 'EUR') }
+
+          it 'sets the currency on the return items from the order' do
+            subject
+            expect(
+              assigns(:form_return_items).all? { |ri|
+                ri.display_amount.currency.iso_code == 'EUR'
+              }
+            ).to be true
+          end
+        end
       end
     end
 

core/app/models/spree/return_item.rb

@@ -177,16 +177,16 @@ def part_of_exchange?
       exchange_requested? || sibling_intended_for_exchange('unexchanged')
     end
 
+    def currency
+      return_authorization.try(:currency) || Spree::Config[:currency]
+    end
+
     private
 
     def persist_acceptance_status_errors
       update(acceptance_status_errors: validator.errors)
     end
 
-    def currency
-      return_authorization.try(:currency) || Spree::Config[:currency]
-    end
-
     def process_inventory_unit!
       inventory_unit.return!
 

core/spec/models/spree/return_item_spec.rb

@@ -142,10 +142,23 @@
     end
   end
 
+  describe "#display_amount" do
+    let(:amount) { 21.22 }
+    let(:order) { build(:order, currency: 'EUR') }
+    let(:return_authorization) { build(:return_authorization, order:) }
+    let(:return_item) { build(:return_item, return_authorization:, amount:) }
+
+    context 'with an amount in the non-default currency' do
+      it "returns a Spree::Money" do
+        expect(return_item.display_amount).to eq Spree::Money.new(amount, currency: 'EUR')
+      end
+    end
+  end
+
   describe "#display_total_excluding_vat" do
     let(:amount) { 21.22 }
     let(:included_tax_total) { 1.22 }
-    let(:return_item) { build(:return_item, amount:, included_tax_total:) }
+    let(:return_item) { create(:return_item, amount:, included_tax_total:) }
 
     it "returns a Spree::Money" do
       expect(return_item.display_total_excluding_vat).to eq Spree::Money.new(amount - included_tax_total)