module Sprockets::Rails::Helper

def self.included(klass)
  klass.class_attribute(*VIEW_ACCESSORS)
  klass.class_eval do
    remove_method :assets_environment
    def assets_environment
      if instance_variable_defined?(:@assets_environment)
        @assets_environment = @assets_environment.cached
      elsif env = self.class.assets_environment
        @assets_environment = env.cached
      else
        nil
      end
    end
  end
end