Forms Refactoring - Service Provider form (#508)

From: https://eaflood.atlassian.net/browse/RUBY-693

Implement delegate and strong parameters strategy in Service Provider form

app/controllers/waste_carriers_engine/service_provided_forms_controller.rb

@@ -9,5 +9,11 @@ def new
     def create
       super(ServiceProvidedForm, "service_provided_form")
     end
+
+    private
+
+    def transient_registration_attributes
+      params.require(:service_provided_form).permit(:is_main_service)
+    end
   end
 end

app/forms/waste_carriers_engine/service_provided_form.rb

@@ -2,22 +2,8 @@
 
 module WasteCarriersEngine
   class ServiceProvidedForm < BaseForm
-    attr_accessor :is_main_service
+    delegate :is_main_service, to: :transient_registration
 
     validates :is_main_service, "waste_carriers_engine/yes_no": true
-
-    def initialize(transient_registration)
-      super
-
-      self.is_main_service = transient_registration.is_main_service
-    end
-
-    def submit(params)
-      # Assign the params for validation and pass them to the BaseForm method for updating
-      self.is_main_service = params[:is_main_service]
-      attributes = { is_main_service: is_main_service }
-
-      super(attributes)
-    end
   end
 end

spec/factories/forms/service_provided_form.rb

@@ -3,9 +3,16 @@
 FactoryBot.define do
   factory :service_provided_form, class: WasteCarriersEngine::ServiceProvidedForm do
     trait :has_required_data do
-      is_main_service { "yes" }
-
-      initialize_with { new(create(:transient_registration, :has_required_data, workflow_state: "service_provided_form")) }
+      initialize_with do
+        new(
+          create(
+            :transient_registration,
+            :has_required_data,
+            workflow_state: "service_provided_form",
+            is_main_service: "yes"
+          )
+        )
+      end
     end
   end
 end