Surround cached fragments with HTML comments (Rails 2.3 initalizer)

cache_with_comment.rb

module ActionController
  module Caching
    module Fragments

      def read_fragment_with_comment(name, options)
        fragment = read_fragment_without_comment(name, options)
        fragment && "\n<!-- cache-hit: #{name} -->\n#{fragment}\n<!-- /cache-hit: #{name} -->\n" || nil
      end
      alias_method_chain :read_fragment, :comment

    end
  end
end

Cool!