config.middleware.use Rack::ContentLength

if !STATUS_WITH_NO_ENTITY_BODY.include?(status.to_i) &&
     !headers['Content-Length'] &&
     !headers['Transfer-Encoding'] &&
     body.respond_to?(:to_ary)

def respond_to?(*args)
  return false if args.first.to_s =~ /^to_ary$/
  super or @body.respond_to?(*args)
end