mocha/express/supertest：'Error: done()多次调用‘

Question

我正在尝试使用mocha和supertest在express中测试我的路由。不幸的是，我似乎无法测试我的重定向。

下面是相关的代码

var should = require('should');
var request = require('supertest');
var app = require('../app');
describe('GET /',function() {
    it('should redirect to the login screen',function(done) {
        request(app)
            .get('/')
    .end(function(err,res) {
        if(err) {
            console.log("ERR: "+err);
            done(err);
        } else {
            console.log("RES:\n",res);
            res.headers.should.have.property('location','/login');
            done();
        }
    });
});

我的app.js是这样的：

app.get('/', routes.index);

我的routes.index看起来像这样：

exports.index = function(req, res){
    if(!req.body.username) {
        res.redirect('/login');
    }
    res.render('index', { title: 'Express' });
};

我的登录页面是：

exports.login = function(req,res) {
    res.render('login',{title: 'Please login'});
};

当我运行测试时，我得到以下错误，这让我认为它实际上运行了不止一次：

  collection router
    GET /
      ◦ should redirect to the login screen: GET / 302 221ms - 40b
      1) should redirect to the login screen
      2) should redirect to the login screen


  8 passing (281 ms)
  2 failing

  1) collection router GET / should redirect to the login screen:
     Error: done() called multiple times
      at multiple (development/git/ivorytower/node_modules/mocha/lib/runnable.js:175:31)
      at done (/development/git/ivorytower/node_modules/mocha/lib/runnable.js:181:26)
      at development/git/ivorytower/node_modules/mocha/lib/runnable.js:197:9
      at development/git/ivorytower/test/routes.js:15:4
      at Test.assert (development/git/ivorytower/node_modules/supertest/lib/test.js:190:3)
      at development/git/ivorytower/node_modules/supertest/lib/test.js:119:10
      at Test.Request.callback (development/git/ivorytower/node_modules/supertest/node_modules/superagent/lib/node/index.js:573:30)
      at Test.<anonymous> (development/git/ivorytower/node_modules/supertest/node_modules/superagent/lib/node/index.js:133:10)
      at Test.EventEmitter.emit (events.js:95:17)
      at IncomingMessage.<anonymous> (development/git/ivorytower/node_modules/supertest/node_modules/superagent/lib/node/index.js:703:12)
      at IncomingMessage.EventEmitter.emit (events.js:117:20)
      at _stream_readable.js:910:16
      at process._tickCallback (node.js:415:13)

  2) collection router GET / should redirect to the login screen:
     Error: done() called multiple times
      at multiple (development/git/ivorytower/node_modules/mocha/lib/runnable.js:175:31)
      at done (development/git/ivorytower/node_modules/mocha/lib/runnable.js:181:26)
      at development/git/ivorytower/node_modules/mocha/lib/runnable.js:197:9
      at development/git/ivorytower/test/routes.js:15:4
      at Test.assert (development/git/ivorytower/node_modules/supertest/lib/test.js:190:3)
      at development/git/ivorytower/node_modules/supertest/lib/test.js:119:10
      at Test.Request.callback (development/git/ivorytower/node_modules/supertest/node_modules/superagent/lib/node/index.js:573:30)
      at Test.<anonymous> (development/git/ivorytower/node_modules/supertest/node_modules/superagent/lib/node/index.js:133:10)
      at Test.EventEmitter.emit (events.js:95:17)
      at IncomingMessage.<anonymous> (development/git/ivorytower/node_modules/supertest/node_modules/superagent/lib/node/index.js:703:12)
      at IncomingMessage.EventEmitter.emit (events.js:117:20)
      at _stream_readable.js:910:16
      at process._tickCallback (node.js:415:13)



npm ERR! weird error 2
npm ERR! not ok code 0

我寻找并发现了一些可能相关的bug，但它们已经有将近一年的历史了，我正在遵循建议的变通方法，但都无济于事：https://github.com/visionmedia/supertest/issues/11#issuecomment-20251424和express：https://github.com/visionmedia/express/blob/master/test/res.redirect.js使用的测试套件我在这里感到困惑。谢谢

Answer 1

问题出在我的路由器代码上：

exports.index = function(req, res){
    if(!req.body.username) {
        res.redirect('/login');
    }
    res.render('index', { title: 'Express' });
};

应该是

exports.index = function(req, res){
    if(!req.body.username) {
        res.redirect('/login');
    } else {
        res.render('index', { title: 'Express' });
    }
};

因此，响应是向它写入一个重定向，然后立即向它呈现一个模板(如果我理解正确的话)。if/then/else块(或if块中的return )修复了该问题。