instance method each_candidate_filepath

# File actionpack/lib/action_dispatch/middleware/static.rb, line 181
      def each_candidate_filepath(path_info)
        return unless path = clean_path(path_info)

        # Most requests are for dynamic routes with nothing like them under the
        # root directory. Probe the path's first segment once before building
        # and stat(2)ing each candidate: when "/users" doesn't exist, neither
        # can "/users/1", "/users/1.html", or "/users/1/index.html".
        root = path == "/"
        slash = path.index("/", 1)
        top_level = slash ? path[1...slash] : path[1..]
        top_level_exists = !root && root_entry?(top_level)

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

        # 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")

            # A top-level "/foo" may be served by "foo.html" rather than by an
            # entry named "foo", so probe for that name instead.
            if slash ? top_level_exists : root_entry?("#{top_level}#{default_ext}")
              yield "#{path}#{default_ext}", default_content_type
            end

            if root
              yield "/#{@index}#{default_ext}", default_content_type if root_entry?("#{@index}#{default_ext}")
            elsif top_level_exists
              yield "#{path}/#{@index}#{default_ext}", default_content_type
            end
          end
        end

        nil
      end