Unit test

app/models/form_handler.rb

@@ -11,7 +11,7 @@ class FormHandler
   end
 
   def current_form
-    forms[forms.keys.sort { |a, b| a.to_i <=> b.to_i }.last]
+    forms[forms.keys.max_by(&:to_i)]
   end
 
 private

spec/models/local_authority_spec.rb

@@ -3,6 +3,7 @@ require "rails_helper"
 RSpec.describe LocalAuthority, type: :model do
   describe "ons code mapping" do
     let(:form) { Form.new("spec/fixtures/forms/2021_2022.json", "2021_2022") }
+
     before do
       allow(FormHandler.instance).to receive(:current_form).and_return(form)
     end

spec/models/organisation_spec.rb

@@ -30,8 +30,22 @@ RSpec.describe Organisation, type: :model do
     end
 
     context "when the organisation only operates in specific local authorities" do
+      let(:ons_code_mappings) do
+        {
+          "" => "Select an option",
+          "E07000223" => "Adur",
+          "E09000023" => "Lewisham",
+          "E08000003" => "Manchester",
+          "E07000178" => "Oxford",
+          "E07000114" => "Thanet",
+          "E09000033" => "Westminster",
+          "E06000014" => "York"
+        }
+      end
+
       before do
         FactoryBot.create(:organisation_la, organisation_id: organisation.id, ons_code: "E07000178")
+        allow(LocalAuthority).to receive(:ons_code_mappings).and_return(ons_code_mappings)
       end
 
       it "has local authorities associated" do