Redmine

Currently the app directories are added to the eager_load paths if the environment name is production.

see: source:trunk/lib/redmine/plugin.rb@17293#96

The decision to add the path to the eager_load paths should depend on the_ eager_load_ setting (Rails.application.config.eager_load) instead of the environment name.
Rails 5 disables autoloading in case eager_load is enabled so using a different environment (e.g. staging) that also enables eager_load will result in plugin classes (e.g. models) are not loaded (uninitialized constant) in this environment.

The attached patch fixes this to use the eager_load setting to decide if the paths should be added to eager_load.