Fix tests of fees in a completed order in models/spree/order_spec by:

- set distributor with taxes on the order
- simplify the factory completed_order_with_fees by replacing shipment with shipping_method and ship_address and letting the order workflow handle shipments and inventory units

spec/factories.rb

@@ -382,18 +382,6 @@ FactoryBot.define do
         shipment.add_shipping_method(evaluator.shipping_method, true)
       end
     end
-
-    trait :shipping_fee do
-      transient do
-        shipping_fee 3
-      end
-
-      after(:create) do |shipment, evaluator|
-        shipping_method = create(:shipping_method_with, :shipping_fee, shipping_fee: evaluator.shipping_fee)
-        shipment.shipping_rates.destroy_all
-        shipment.add_shipping_method(shipping_method, true)
-      end
-    end
   end
 
   factory :distributor_enterprise_with_tax, parent: :distributor_enterprise do
@@ -407,16 +395,16 @@ FactoryBot.define do
       payment_fee 5
     end
 
-    shipments { [ create(:shipment_with, :shipping_fee, shipping_fee: shipping_fee) ] }
+    ship_address { create(:address) }
 
     after(:create) do |order, evaluator|
+      create(:shipping_method_with, :shipping_fee, shipping_fee: evaluator.shipping_fee)
+
       create(:line_item, order: order)
       payment_calculator = build(:calculator_per_item, preferred_amount: evaluator.payment_fee)
       payment_method = create(:payment_method, calculator: payment_calculator)
       create(:payment, order: order, amount: order.total, payment_method: payment_method, state: 'checkout')
 
-      # skip the rebuilding of order.shipments from line_items and stock locations (this is enforced in checkout step :address to :delivery)
-      order.stub(:create_proposed_shipments)
       while !order.completed? do break unless order.next! end
     end
   end

spec/models/spree/order_spec.rb

@@ -655,7 +655,8 @@ describe Spree::Order do
   end
 
   describe "a completed order with shipping and transaction fees" do
-    let(:order) { create(:completed_order_with_fees, shipping_fee: shipping_fee, payment_fee: payment_fee) }
+    let(:distributor) { create(:distributor_enterprise_with_tax) }
+    let(:order) { create(:completed_order_with_fees, distributor: distributor, shipping_fee: shipping_fee, payment_fee: payment_fee) }
     let(:shipping_fee) { 3 }
     let(:payment_fee) { 5 }
     let(:item_num) { order.line_items.length }