each_candidate_filepath

# File actionpack/lib/action_dispatch/middleware/static.rb, line 160
      def each_candidate_filepath(path_info)
        return unless path = clean_path(path_info)

        ext = ::File.extname(path)
        content_type = ::Rack::Mime.mime_type(ext, nil)
        yield path, content_type || "text/plain"

        # Tack on .html and /index.html only for paths that don't have
        # an explicit, resolvable file extension. No need to check
        # for foo.js.html and foo.js/index.html.
        unless content_type
          default_ext = ::ActionController::Base.default_static_extension
          if ext != default_ext
            default_content_type = ::Rack::Mime.mime_type(default_ext, "text/plain")

            yield "#{path}#{default_ext}", default_content_type
            yield "#{path}/#{@index}#{default_ext}", default_content_type
          end
        end

        nil
      end