Require lib files on engine load, not per-request

Created by: gracewashere

Why?

After changing app/controllers/admin/application_controller or other controllers that required Administrate, the app would throw an error on the following request.

NameError in Admin::ApplicationController#show
uninitialized constant Administrate::ResourceResolver

For some reason I'm not sure of, moving the require statements into the rails engine file takes care of the problem. The engine is required from lib/administrate.rb, which I assume is required by Bundler at the start of the process.

Developers can now edit classes without invalidating the loaded classes.

Tags: #ruby