Do not couple with controller's ivar and session

app/controllers/checkout_controller.rb

@@ -41,6 +41,7 @@ class CheckoutController < Spree::CheckoutController
         set_default_ship_address
 
         ResetOrderService.new(self).call
+        session[:access_token] = current_order.token
 
         flash[:success] = t(:order_processed_successfully)
         respond_to do |format|
@@ -59,6 +60,10 @@ class CheckoutController < Spree::CheckoutController
     end
   end
 
+  def expire_current_order
+    session[:order_id] = nil
+    @current_order = nil
+  end
 
   private
 

app/services/reset_order_service.rb

@@ -3,13 +3,20 @@ class ResetOrderService < SimpleDelegator
     distributor = current_order.distributor
     token = current_order.token
 
-    session[:order_id] = nil
-    __getobj__.instance_variable_set(:@current_order, nil)
-    current_order(true)
+    controller.expire_current_order
+    build_new_order(distributor, token)
+  end
 
+  private
+
+  def build_new_order(distributor, token)
+    current_order(true)
     current_order.set_distributor!(distributor)
     current_order.tokenized_permission.token = token
     current_order.tokenized_permission.save!
-    session[:access_token] = token
+  end
+
+  def controller
+    __getobj__
   end
 end

spec/controllers/checkout_controller_spec.rb

@@ -85,10 +85,42 @@ describe CheckoutController do
       controller.send(:clear_ship_address)
     end
 
-    it "sets the new order's token to the same as the old order" do
-      order = controller.current_order(true)
-      spree_post :update, order: {}
-      expect(controller.current_order.token).to eq order.token
+    context 'when completing the order' do
+      before do
+        order.state = 'complete'
+        allow(order).to receive(:update_attributes).and_return(true)
+        allow(order).to receive(:next).and_return(true)
+        allow(order).to receive(:set_distributor!).and_return(true)
+      end
+
+      it "sets the new order's token to the same as the old order" do
+        order = controller.current_order(true)
+        spree_post :update, order: {}
+        expect(controller.current_order.token).to eq order.token
+      end
+
+      it 'expires the current order' do
+        allow(controller).to receive(:expire_current_order)
+        put :update, order: {}
+        expect(controller).to have_received(:expire_current_order)
+      end
+
+      it 'sets the access_token of the session' do
+        put :update, order: {}
+        expect(session[:access_token]).to eq(controller.current_order.token)
+      end
+    end
+  end
+
+  describe '#expire_current_order' do
+    it 'empties the order_id of the session' do
+      expect(session).to receive(:[]=).with(:order_id, nil)
+      controller.expire_current_order
+    end
+
+    it 'resets the @current_order ivar' do
+      controller.expire_current_order
+      expect(controller.instance_variable_get(:@current_order)).to be_nil
     end
   end
 

spec/services/reset_order_service_spec.rb

@@ -14,15 +14,21 @@ describe ResetOrderService do
       tokenized_permission: tokenized_permission,
     )
   end
-  let(:session) { double(:session) }
-  let(:controller) { double(:controller, current_order: new_order, session: session) }
+  let(:controller) do
+    double(
+      :controller,
+      current_order: new_order,
+      expire_current_order: true
+    )
+  end
   let(:reset_order_service) { described_class.new(controller) }
 
   before do
-    allow(current_order).to receive(:tokenized_permission).and_return(tokenized_permission)
+    allow(current_order)
+      .to receive(:tokenized_permission)
+      .and_return(tokenized_permission)
+
     allow(tokenized_permission).to receive(:token=)
-    allow(session).to receive(:[]=).with(:order_id, nil)
-    allow(session).to receive(:[]=).with(:access_token, current_token)
   end
 
   describe '#call' do
@@ -31,16 +37,6 @@ describe ResetOrderService do
       expect(controller).to have_received(:current_order).once.with(true)
     end
 
-    it 'empties the order_id of the session' do
-      reset_order_service.call
-      expect(session).to have_received(:[]=).with(:order_id, nil)
-    end
-
-    it 'resets the @current_order var' do
-      reset_order_service.call
-      expect(controller.instance_variable_get(:@current_order)).to be_nil
-    end
-
     it 'sets the new order\'s distributor to the same as the old order' do
       reset_order_service.call
 
@@ -60,10 +56,5 @@ describe ResetOrderService do
       reset_order_service.call
       expect(tokenized_permission).to have_received(:save!)
     end
-
-    it 'sets the access_token of the session' do
-      reset_order_service.call
-      expect(session).to have_received(:[]=).with(:access_token, current_token)
-    end
   end
 end