Add warning for deleting page at end of secondary skip route

app/controllers/pages_controller.rb

@@ -21,6 +21,7 @@ def delete
 
     @check_page = PageRepository.find(page_id: @page.routing_conditions.first.check_page_id, form_id: current_form.id) if @page.routing_conditions.first&.secondary_skip?
     @routing_page = PageRepository.find(page_id: @page_goto_conditions.first.routing_page_id, form_id: current_form.id) if @page_goto_conditions.any?
+    @check_page = PageRepository.find(page_id: @page_goto_conditions.first.check_page_id, form_id: current_form.id) if @page_goto_conditions.any?
 
     @delete_confirmation_input = Forms::DeleteConfirmationInput.new
 

app/views/pages/delete.html.erb

@@ -17,6 +17,12 @@
 
           t(".notification_banner.start_of_route.html", routing_page_position: @page.position, routing_page_show_routes_href: show_routes_path(current_form.id, @page.id))
         end %>
+      <% elsif @page_goto_conditions.present? && @page_goto_conditions.first&.secondary_skip? %>
+        <%= govuk_notification_banner(title_text: "Important") do |banner|
+          banner.with_heading(text: t(".notification_banner.end_of_secondary_skip_route.heading_text", goto_page_position: @page.position), tag: :h3)
+
+          t(".notification_banner.end_of_secondary_skip_route.html", check_page_position: @check_page.position, check_page_show_routes_href: show_routes_path(current_form.id, @check_page.id))
+        end %>
       <% elsif @page_goto_conditions.present? %>
         <%= govuk_notification_banner(title_text: "Important") do |banner|
           banner.with_heading(text: t(".notification_banner.end_of_route.heading_text", goto_page_position: @page.position), tag: :h3)

config/locales/en.yml

@@ -1141,6 +1141,13 @@ en:
               <a class="govuk-notification-banner__link" href="%{routing_page_show_routes_href}">Question %{routing_page_position}’s route</a>
               goes to this question. If you delete this question, question %{routing_page_position}’s routes will also be deleted.
             </p>
+        end_of_secondary_skip_route:
+          heading_text: Question %{goto_page_position} is at the end of a route
+          html: |
+            <p class="govuk-body">
+              <a class="govuk-notification-banner__link" href="%{check_page_show_routes_href}">Question %{check_page_position}’s route</a>
+              goes to this question. If you delete this question, the route to it will also be deleted.
+            </p>
         start_of_route:
           heading_text: Question %{routing_page_position} is the start of a route
           html: |

spec/requests/pages_controller_spec.rb

@@ -247,6 +247,52 @@
           end
         end
       end
+
+      context "when page to delete is at the end of a secondary skip route" do
+        let(:pages) do
+          [
+            build(
+              :page,
+              :with_selection_settings,
+              id: 1,
+              form_id: 2,
+              position: 1,
+              question_text: "What is your favourite colour?",
+              selection_options: [{ name: "Red" }, { name: "Green" }, { name: "Blue" }],
+              only_one_option: true,
+              routing_conditions: [
+                build(:condition, routing_page_id: 1, check_page_id: 1, value: "green", goto_page_id: 3),
+              ],
+            ),
+            build(
+              :page,
+              id: 5,
+              form_id: 2,
+              position: 5,
+              routing_conditions: [
+                build(:condition, routing_page_id: 5, check_page_id: 1, value: nil, goto_page_id: 8),
+              ],
+            ),
+            build(
+              :page,
+              id: 8,
+              form_id: 2,
+              position: 8,
+            ),
+          ]
+        end
+
+        let(:page) { pages.last }
+
+        it "renders a warning about deleting this page" do
+          assert_select(".govuk-notification-banner", count: 1) do
+            assert_select "*", "Important"
+            assert_select "h3", "Question 8 is at the end of a route"
+            assert_select "p.govuk-body a", "Question 1’s route"
+            assert_select "p.govuk-body", /Question 1’s route\s*goes to this question. If you delete this question, the route to it will also be deleted./
+          end
+        end
+      end
     end
   end
 

spec/views/pages/delete.html.erb_spec.rb

@@ -200,4 +200,71 @@
       end
     end
   end
+
+  describe "when page to delete is at the end of a secondary skip route" do
+    let(:check_page) do
+      build(
+        :page,
+        id: 1,
+        form_id: 1,
+        position: 3,
+        routing_conditions: [
+          build(:condition, routing_page_id: 1, check_page_id: 1, goto_page_id: 3),
+        ],
+      )
+    end
+
+    let(:routing_page) do
+      build(
+        :page,
+        id: 12,
+        form_id: 1,
+        position: 7,
+        routing_conditions: [
+          build(:condition, routing_page_id: 12, check_page_id: 1, goto_page_id: 9),
+        ],
+      )
+    end
+
+    let(:page) do
+      build(
+        :page,
+        id: 9,
+        form_id: 1,
+        position: 12,
+      )
+    end
+
+    before do
+      assign(:check_page, check_page)
+      assign(:page_goto_conditions, routing_page.routing_conditions)
+
+      render locals: { current_form: }
+    end
+
+    it "renders a notification banner" do
+      expect(rendered).to have_css ".govuk-notification-banner"
+    end
+
+    describe "notification banner" do
+      subject(:banner) { rendered.html.at_css(".govuk-notification-banner") }
+
+      it { is_expected.to have_text "Important" }
+      it { is_expected.to have_css "h3.govuk-notification-banner__heading", text: "Question 12 is at the end of a route", count: 1 }
+      it { is_expected.to have_link "Question 3’s route", class: "govuk-notification-banner__link", href: show_routes_path(1, 1) }
+      it { is_expected.to have_css "p.govuk-body", text: "Question 3’s route goes to this question. If you delete this question, the route to it will also be deleted.", normalize_ws: true }
+    end
+
+    context "but there was an error in the user's input" do
+      let(:delete_confirmation_input) do
+        delete_confirmation_input = Forms::DeleteConfirmationInput.new(confirm: "")
+        delete_confirmation_input.validate
+        delete_confirmation_input
+      end
+
+      it "does not render the notification banner" do
+        expect(rendered).not_to have_css ".govuk-notification-banner"
+      end
+    end
+  end
 end