Fix Shipment#update_attributes_and_order - run full order updater

core/app/models/spree/shipment.rb

@@ -296,25 +296,9 @@ def update_attributes_and_order(params = {})
       if update_attributes params
         if params.key? :selected_shipping_rate_id
           # Changing the selected Shipping Rate won't update the cost (for now)
-          # so we persist the Shipment#cost before calculating order shipment
-          # total and updating payment state (given a change in shipment cost
-          # might change the Order#payment_state)
+          # so we persist the Shipment#cost before running `order.update!`
           update_amounts
-
-          order.updater.update_shipment_total
-          order.updater.update_payment_state
-
-          # Update shipment state only after order total is updated because it
-          # (via Order#paid?) affects the shipment state (YAY)
-          update_columns(
-            state: determine_state(order),
-            updated_at: Time.current
-          )
-
-          # And then it's time to update shipment states and finally persist
-          # order changes
-          order.updater.update_shipment_state
-          order.updater.persist_totals
+          order.update!
         end
 
         true

core/spec/lib/spree/core/testing_support/factories/order_factory_spec.rb

@@ -75,6 +75,22 @@
         )
       end
     end
+
+    context 'when shipments should be taxed' do
+      let!(:ship_address) { create(:address) }
+      let!(:tax_zone) { create(:global_zone) } # will include the above address
+      let!(:tax_rate) { create(:tax_rate, amount: 0.10, zone: tax_zone, tax_category: tax_category) }
+
+      let(:tax_category) { create(:tax_category) }
+      let(:shipping_method) { create(:shipping_method, tax_category: tax_category, zones: [tax_zone]) }
+
+      it 'shipments get a tax adjustment' do
+        order = create(factory, ship_address: ship_address, shipping_method: shipping_method)
+        shipment = order.shipments[0]
+
+        expect(shipment.additional_tax_total).to be > 0
+      end
+    end
   end
 
   describe 'order ready to complete' do

core/spec/models/spree/shipment_spec.rb

@@ -546,32 +546,49 @@
   end
 
   context "changes shipping rate via general update" do
-    let(:store) { create :store }
+    let!(:ship_address) { create(:address) }
+    let!(:tax_zone) { create(:global_zone) } # will include the above address
+    let!(:tax_rate) { create(:tax_rate, amount: 0.10, zone: tax_zone, tax_category: tax_category) }
+    let(:tax_category) { create(:tax_category) }
+
     let(:order) do
-      Spree::Order.create(
-        payment_total: 100,
-        payment_state: 'paid',
-        total: 100,
-        item_total: 100,
-        store: store
+      create(
+        :order_ready_to_ship,
+        ship_address: ship_address,
+        shipment_cost: 10,
+        shipping_method: ten_dollar_shipping_method,
+        line_items_count: 1,
+        line_items_price: 100,
       )
     end
 
-    let(:shipment) { Spree::Shipment.create order_id: order.id }
+    let(:ten_dollar_shipping_method)    { create(:shipping_method, tax_category: tax_category, zones: [tax_zone], cost: 10) }
+    let(:twenty_dollar_shipping_method) { create(:shipping_method, tax_category: tax_category, zones: [tax_zone], cost: 20) }
 
-    let(:shipping_rate) do
-      Spree::ShippingRate.create shipment_id: shipment.id, cost: 10
-    end
+    let(:shipment) { order.shipments[0] }
 
-    before do
-      shipment.update_attributes_and_order selected_shipping_rate_id: shipping_rate.id
+    let(:twenty_dollar_shipping_rate) do
+      create(:shipping_rate, cost: 20, shipment: shipment, shipping_method: twenty_dollar_shipping_method)
     end
 
     it "updates everything around order shipment total and state" do
-      expect(shipment.cost.to_f).to eq 10
+      expect(shipment.state).to eq 'ready'
+      expect(shipment.cost).to eq 10
+      expect(shipment.additional_tax_total).to eq 1
+
+      expect(order.shipment_total).to eq 10
+      expect(order.total).to eq 121 # shipment: 10 + 1 (tax) + line item: 100 + 10 (tax)
+      expect(order.payment_state).to eq 'paid'
+
+      shipment.update_attributes_and_order selected_shipping_rate_id: twenty_dollar_shipping_rate.id
+
       expect(shipment.state).to eq 'pending'
-      expect(shipment.order.total.to_f).to eq 110
-      expect(shipment.order.payment_state).to eq 'balance_due'
+      expect(shipment.cost).to eq 20
+      expect(shipment.additional_tax_total).to eq 2
+
+      expect(order.shipment_total).to eq 20
+      expect(order.total).to eq 132 # shipment: 20 + 2 (tax) + line item: 100 + 10 (tax)
+      expect(order.payment_state).to eq 'balance_due'
     end
   end