Wrap reloadable constant calls in to_prepare

Author: JonRowe

lib/rspec-rails.rb

@@ -8,13 +8,17 @@ module Rails
     class Railtie < ::Rails::Railtie
       # As of Rails 5.1.0 you can register directories to work with `rake notes`
       require 'rails/source_annotation_extractor'
-      ::Rails::SourceAnnotationExtractor::Annotation.register_directories("spec")
+      config.to_prepare do
+        ::Rails::SourceAnnotationExtractor::Annotation.register_directories("spec")
+      end
       generators = config.app_generators
       generators.integration_tool :rspec
       generators.test_framework :rspec
 
       generators do
-        ::Rails::Generators.hidden_namespaces.reject! { |namespace| namespace.to_s.start_with?("rspec") }
+        config.to_prepare do
+          ::Rails::Generators.hidden_namespaces.reject! { |namespace| namespace.to_s.start_with?("rspec") }
+        end
       end
 
       rake_tasks do