Merge pull request #3023 from nebulab/issue-3020-availability-validat…

…ions

Rescue from `Spree::Order::InsufficientStock` on `frontend` checkout flow

core/config/locales/en.yml

@@ -1472,6 +1472,7 @@ en:
     inventory_adjustment: Inventory Adjustment
     inventory_canceled: Inventory canceled
     inventory_error_flash_for_insufficient_quantity: "%{names} became unavailable."
+    inventory_error_flash_for_insufficient_shipment_quantity: "Quantity selected of %{unavailable_items} is not available. Still, items may be available from another stock location, please try again."
     inventory_not_available: Inventory not available for %{item}.
     inventory_state: Inventory State
     inventory_states:

frontend/app/controllers/spree/checkout_controller.rb

@@ -24,6 +24,7 @@ class CheckoutController < Spree::StoreController
     helper 'spree/orders'
 
     rescue_from Spree::Core::GatewayError, with: :rescue_from_spree_gateway_error
+    rescue_from Spree::Order::InsufficientStock, with: :insufficient_stock_error
 
     # Updates the order and advances to the next state (when possible.)
     def update
@@ -233,5 +234,22 @@ def rescue_from_spree_gateway_error(exception)
     def check_authorization
       authorize!(:edit, current_order, cookies.signed[:guest_token])
     end
+
+    def insufficient_stock_error
+      packages = @order.shipments.map(&:to_package)
+      if packages.empty?
+        flash[:error] = I18n.t('spree.insufficient_stock_for_order')
+        redirect_to cart_path
+      else
+        availability_validator = Spree::Stock::AvailabilityValidator.new
+        unavailable_items = @order.line_items.reject { |line_item| availability_validator.validate(line_item) }
+        if unavailable_items.any?
+          item_names = unavailable_items.map(&:name).to_sentence
+          flash[:error] = t('spree.inventory_error_flash_for_insufficient_shipment_quantity', unavailable_items: item_names)
+          @order.restart_checkout_flow
+          redirect_to spree.checkout_state_path(@order.state)
+        end
+      end
+    end
   end
 end

frontend/spec/controllers/spree/checkout_controller_spec.rb

@@ -419,6 +419,45 @@ def post_address
         expect(flash[:error]).to eq(I18n.t('spree.payment_processing_failed'))
       end
     end
+
+    context "when InsufficientStock error is raised" do
+      before do
+        allow(controller).to receive_messages current_order: order
+        allow(controller).to receive_messages check_authorization: true
+        allow(controller).to receive_messages ensure_sufficient_stock_lines: true
+      end
+
+      context "when the order has no shipments" do
+        let(:order) { Spree::TestingSupport::OrderWalkthrough.up_to(:address) }
+
+        before do
+          allow(order).to receive_messages shipments: []
+          # Order#next is the tipical failure point here:
+          allow(order).to receive(:next).and_raise(Spree::Order::InsufficientStock)
+        end
+
+        it "redirects the customer to the cart page with an error message" do
+          put :update, params: { state: order.state, order: {} }
+          expect(flash[:error]).to eq(I18n.t('spree.insufficient_stock_for_order'))
+          expect(response).to redirect_to(spree.cart_path)
+        end
+      end
+
+      context "when the order has shipments" do
+        let(:order) { Spree::TestingSupport::OrderWalkthrough.up_to(:payment) }
+
+        context "when items become somehow not available anymore" do
+          before { Spree::StockItem.update_all backorderable: false }
+
+          it "redirects the customer to the address checkout page with an error message" do
+            put :update, params: { state: order.state, order: {} }
+            error = I18n.t('spree.inventory_error_flash_for_insufficient_shipment_quantity', unavailable_items: order.products.first.name)
+            expect(flash[:error]).to eq(error)
+            expect(response).to redirect_to(spree.checkout_state_path(state: :address))
+          end
+        end
+      end
+    end
   end
 
   context "When last inventory item has been purchased" do

frontend/spec/features/checkout_confirm_insufficient_stock_spec.rb

@@ -0,0 +1,71 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe "Checkout confirm page submission", type: :feature do
+  include_context 'checkout setup'
+
+  context "when the product from the order is not backorderable but has enough stock quantity" do
+    let(:user) { create(:user) }
+
+    let(:order) { Spree::TestingSupport::OrderWalkthrough.up_to(:payment) }
+    let(:order_product) { order.products.first }
+    let(:order_stock_item) { order_product.stock_items.first }
+
+    before do
+      order_stock_item.update! backorderable: false
+      order_stock_item.set_count_on_hand(1)
+      allow_any_instance_of(Spree::CheckoutController).to receive_messages(current_order: order)
+      allow_any_instance_of(Spree::CheckoutController).to receive_messages(try_spree_current_user: user)
+      allow_any_instance_of(Spree::OrdersController).to receive_messages(try_spree_current_user: user)
+    end
+
+    context 'when there are not other backorderable stock locations' do
+      context 'when the customer is on the confirm page and the availabilty drops to zero' do
+        before do
+          visit spree.checkout_state_path(:confirm)
+          order_stock_item.set_count_on_hand(0)
+        end
+
+        it 'redirects to cart page and shows an unavailable product message' do
+          click_button "Place Order"
+          expect(page).to have_content "#{order_product.name} became unavailable"
+          expect(page).to have_current_path spree.cart_path
+        end
+      end
+    end
+
+    context 'when there is another backorderable stock location' do
+      before do
+        create :stock_location, backorderable_default: true, default: false
+      end
+
+      context 'when the customer is on the confirm page and the availabilty drops to zero' do
+        before do
+          visit spree.checkout_state_path(:confirm)
+          order_stock_item.set_count_on_hand(0)
+        end
+
+        it "redirects to the address checkout page and shows an availability changed message" do
+          click_button "Place Order"
+          error_message = "Quantity selected of #{order_product.name} is not available. Still, items may be available from another stock location, please try again."
+          expect(page).to have_content error_message
+          expect(page).to have_current_path spree.checkout_state_path(:address)
+        end
+
+        it "can still complete the order using the backorderable stock location by restarting the checkout" do
+          click_button "Place Order"
+          expect(page).to have_current_path spree.checkout_state_path(:address)
+          click_button "Save and Continue"
+          expect(page).to have_current_path spree.checkout_state_path(:delivery)
+          click_button "Save and Continue"
+          expect(page).to have_current_path spree.checkout_state_path(:payment)
+          click_button "Save and Continue"
+          expect(page).to have_current_path spree.checkout_state_path(:confirm)
+          click_button "Place Order"
+          expect(page).to have_content 'Your order has been processed successfully'
+        end
+      end
+    end
+  end
+end