anchor.diff:      response.headers.set('location',
           serverUrl.resolve('/loop?${n + 1}').toString());
       response.contentLength = 0;
  -    response.outputStream.close();
  +    closeResponse(request, response);
     });
   
     _server.addRequestHandler((request) => request.path == '/redirect',
  
positive.code:       (request, response) {
      response.statusCode = 400;
      response.contentLength = 0;
      response.outputStream.close();
    });
  
    _server.addRequestHandler((request) => request.path == '/loop',
  
negative.code:     response.statusCode = 302;
      response.headers.set('location', serverUrl.resolve('/').toString());
      response.contentLength = 0;
      closeResponse(request, response);
    });
  
    _server.defaultRequestHandler = (request, response) {
  