Save default addresses when requested during checkout

spec/controllers/split_checkout_controller_spec.rb

@@ -82,6 +82,22 @@ describe SplitCheckoutController, type: :controller do
           expect(response).to redirect_to checkout_step_path(:payment)
           expect(order.reload.state).to eq "payment"
         end
+
+        describe "saving default addresses" do
+          it "updates default bill address on user and customer" do
+            put :update, params: params.merge({ order: { save_bill_address: true } })
+
+            expect(order.customer.bill_address).to eq(order.bill_address)
+            expect(order.user.bill_address).to eq(order.bill_address)
+          end
+
+          it "updates default ship address on user and customer" do
+            put :update, params: params.merge({ order: { save_ship_address: true } })
+
+            expect(order.customer.ship_address).to eq(order.ship_address)
+            expect(order.user.ship_address).to eq(order.ship_address)
+          end
+        end
       end
     end