call

# File actionpack/lib/action_dispatch/middleware/public_exceptions.rb, line 10
    def call(env)
      status      = env["PATH_INFO"][1..-1]
      locale_path = "#{public_path}/#{status}.#{I18n.locale}.html" if I18n.locale
      path        = "#{public_path}/#{status}.html"

      if locale_path && File.exist?(locale_path)
        render(status, File.read(locale_path))
      elsif File.exist?(path)
        render(status, File.read(path))
      else
        [404, { "X-Cascade" => "pass" }, []]
      end
    end