fix: MissingResourceError on polymorphic field

lib/avo.rb

@@ -36,19 +36,20 @@ class MissingGemError < StandardError; end
   class DeprecatedAPIError < StandardError; end
 
   class MissingResourceError < StandardError
-    def initialize(resource_name)
-      super(missing_resource_message(resource_name))
+    def initialize(model_class, field_name = nil)
+      super(missing_resource_message(model_class, field_name))
     end
 
     private
 
-    def missing_resource_message(resource_name)
-      name = resource_name.to_s.underscore
+    def missing_resource_message(model_class, field_name)
+      model_name = model_class.to_s.underscore
+      field_name ||= model_name
 
-      "Failed to find a resource while rendering the :#{name} field.\n" \
-      "You may generate a resource for it by running 'rails generate avo:resource #{name.singularize}'.\n" \
+      "Failed to find a resource while rendering the :#{field_name} field.\n" \
+      "You may generate a resource for it by running 'rails generate avo:resource #{model_name}'.\n" \
       "\n" \
-      "Alternatively add the 'use_resource' option to the :#{name} field to specify a custom resource to be used.\n" \
+      "Alternatively add the 'use_resource' option to the :#{field_name} field to specify a custom resource to be used.\n" \
       "More info on https://docs.avohq.io/#{Avo::VERSION[0]}.0/resources.html."
     end
   end
@@ -75,7 +76,7 @@ def init
       Avo::Current.error_manager = Avo::ErrorManager.build
       # Check rails version issues only on NON Production environments
       unless Rails.env.production?
-        check_rails_version_issues 
+        check_rails_version_issues
         display_menu_editor_warning
       end
       Avo::Current.resource_manager = Avo::Resources::ResourceManager.build

lib/avo/fields/base_field.rb

@@ -313,7 +313,7 @@ def in_action?
       def get_resource_by_model_class(model_class)
         resource = Avo.resource_manager.get_resource_by_model_class(model_class)
 
-        resource || (raise Avo::MissingResourceError.new(model_class))
+        resource || (raise Avo::MissingResourceError.new(model_class, id))
       end
     end
   end