Display a warning when clicking the generate invoice button if an ABN is required but not present

app/helpers/spree/admin/orders_helper.rb

@@ -10,6 +10,17 @@ module Spree
         links.join(' ').html_safe # rubocop:disable Rails/OutputSafety
       end
 
+      def generate_invoice_button(order)
+        if order.distributor.can_invoice?
+          button_link_to t(:create_or_update_invoice), generate_admin_order_invoices_path(@order),
+                         data: { method: 'post' }, icon: 'icon-plus'
+        else
+          button_link_to t(:create_or_update_invoice), "#", data: {
+            confirm: t(:must_have_valid_business_number, enterprise_name: @order.distributor.name)
+          }, icon: 'icon-plus'
+        end
+      end
+
       def line_item_shipment_price(line_item, quantity)
         Spree::Money.new(line_item.price * quantity, currency: line_item.currency)
       end

app/views/spree/admin/invoices/index.html.haml

@@ -11,7 +11,7 @@
 
 - content_for :page_actions do
   - if show_generate_invoice_button?(@order)
-    %li= button_link_to t(:create_or_update_invoice), generate_admin_order_invoices_path(@order), :icon => 'icon-plus', data: { method: 'post' }
+    %li= generate_invoice_button(@order)
   = render partial: 'spree/admin/shared/order_links'
   %li= button_link_to t(:back_to_orders_list), admin_orders_path, :icon => 'icon-arrow-left'
 

config/locales/en.yml

@@ -437,7 +437,7 @@ en:
   cancel_order: "Cancel Order"
   confirm_send_invoice: "An invoice for this order will be sent to the customer. Are you sure you want to continue?"
   confirm_resend_order_confirmation: "Are you sure you want to resend the order confirmation email?"
-  must_have_valid_business_number: "%{enterprise_name} must have a valid ABN before invoices can be sent."
+  must_have_valid_business_number: "%{enterprise_name} must have a valid ABN before invoices can be used."
   invoice: "Invoice"
   invoices: "Invoices"
   file: "File"

spec/controllers/spree/admin/orders/invoices_spec.rb

@@ -43,7 +43,7 @@ describe Spree::Admin::OrdersController, type: :controller do
             end.to_not change{ Spree::OrderMailer.deliveries.count }
             expect(response).to redirect_to spree.edit_admin_order_path(order)
             expect(flash[:error])
-              .to eq "#{distributor.name} must have a valid ABN before invoices can be sent."
+              .to eq "#{distributor.name} must have a valid ABN before invoices can be used."
           end
         end
 

spec/system/admin/order_spec.rb

@@ -727,14 +727,14 @@ describe '
                 click_link "Print Invoice"
               end
               expect(message)
-                .to eq "#{distributor1.name} must have a valid ABN before invoices can be sent."
+                .to eq "#{distributor1.name} must have a valid ABN before invoices can be used."
 
               find("#links-dropdown .ofn-drop-down").click
               message = accept_prompt do
                 click_link "Send Invoice"
               end
               expect(message)
-                .to eq "#{distributor1.name} must have a valid ABN before invoices can be sent."
+                .to eq "#{distributor1.name} must have a valid ABN before invoices can be used."
             end
           end
         end
@@ -1172,6 +1172,7 @@ describe '
           }
 
           before do
+            Spree::Config[:enterprise_number_required_on_invoices?] = false
             visit spree.admin_order_invoices_path(order1)
           end
 
@@ -1197,6 +1198,22 @@ describe '
             expect(page).to have_link("Download",
                                       href: download_href)
           end
+
+          context "the Create or Update Invoice button" do
+            context "when an ABN number is mandatory for invoices but not present" do
+              before do
+                Spree::Config[:enterprise_number_required_on_invoices?] = true
+              end
+
+              it "displays a warning that an ABN is required when it's clicked" do
+                visit spree.admin_order_invoices_path(order1)
+                message = accept_prompt { click_link "Create or Update Invoice" }
+                distributor = order1.distributor
+                expect(message)
+                  .to eq "#{distributor.name} must have a valid ABN before invoices can be used."
+              end
+            end
+          end
         end
       end