module Docs  class FileScraper < Scraper    SOURCE_DIRECTORY = File.expand_path '../../../../../docs', __FILE__     Response = Struct.new :body, :url     class << self      def inherited(subclass)        super        subclass.base_url = base_url      end    end     self.base_url = 'http://localhost/'     html_filters.push 'clean_local_urls'     def source_directory      @source_directory ||= File.join(SOURCE_DIRECTORY, self.class.path)    end     private     def assert_source_directory_exists      unless Dir.exist?(source_directory)        raise SetupError, "The #{self.class.name} scraper requires the original documentation files to be stored in the \"#{source_directory}\" directory."      end    end     def request_one(url)      assert_source_directory_exists      Response.new read_file(File.join(source_directory, url_to_path(url))), URL.parse(url)    end     def request_all(urls)      assert_source_directory_exists      queue = [urls].flatten      until queue.empty?        result = yield request_one(queue.shift)        queue.concat(result) if result.is_a? Array      end    end     def process_response?(response)      response.body.present?    end     def url_to_path(url)      url.remove(base_url.to_s)    end     def read_file(path)      File.read(path)    rescue      instrument 'warn.doc', msg: "Failed to open file: #{path}"      nil    end  endend