Add more_than_year_from_today merge date validation

app/controllers/merge_requests_controller.rb

@@ -143,6 +143,7 @@ private
 
       if [day, month, year].none?(&:blank?) && Date.valid_date?(year.to_i, month.to_i, day.to_i)
         merge_request_params["merge_date"] = Time.zone.local(year.to_i, month.to_i, day.to_i)
+        @merge_request.errors.add(:merge_date, :more_than_year_from_today) if Time.zone.local(year.to_i, month.to_i, day.to_i) - 1.year > Time.zone.today
       else
         @merge_request.errors.add(:merge_date, :invalid)
       end

config/locales/en.yml

@@ -183,6 +183,7 @@ en:
             merge_date:
               blank: "Enter a merge date."
               invalid: "Enter a valid merge date."
+              more_than_year_from_today: "The merge date must not be later than a year from today’s date."
             existing_absorbing_organisation:
               blank: "You must answer absorbing organisation already active?"
         notification:

spec/requests/merge_requests_controller_spec.rb

@@ -396,6 +396,24 @@ RSpec.describe MergeRequestsController, type: :request do
             }.from(nil).to(Time.zone.local(2022, 4, 10))
           end
         end
+
+        context "when merge date set to a date more than 1 year in the future" do
+          let(:merge_request) { MergeRequest.create!(requesting_organisation: organisation) }
+          let(:params) do
+            { merge_request: { page: "merge_date", "merge_date(3i)": "#{Time.zone.now.day + 1}", "merge_date(2i)": "#{Time.zone.now.month}", "merge_date(1i)": "#{Time.zone.now.year + 1}" } }
+          end
+
+          let(:request) do
+            patch "/merge-request/#{merge_request.id}", headers:, params:
+          end
+
+          it "displays the page with an error message" do
+            request
+
+            expect(response).to have_http_status(:unprocessable_entity)
+            expect(page).to have_content("The merge date must not be later than a year from today’s date.")
+          end
+        end
       end
 
       describe "from merging_organisations page" do