Javascript 测试返回next（）/next（“路由”）的express中间件

我创建了这个中间件，当路由的唯一参数由

queryItems

定义时，它将返回

next（）

我最近发现哪些赝品表达了

req

和

res

对象。但是，它不会伪造

next

。我想知道该怎么做？下面是我打开

next

回调并在其中定义

expect

语句的示例

middleware.hasOnlyQuery = function(queryItems){
  return function(req, res, next){
    if(typeof queryItems == "string") queryItems = [queryItems]
    if(_.hasOnly(req.query, queryItems)) return next()
    return next("route")
  }
}

这是测试

it("should only have shop query", function(done){
  var req = httpMocks.createRequest({
      method: 'GET',
      query: {
        foo: "bar"
      }
  });
  var res = httpMocks.createResponse()
  var fn = middleware.hasOnlyQuery(["foo"])(req, res, function(err){
    expect(err).to.equal()
    return done()
  })
})

it("should not only have shop query", function(done){
  var req = httpMocks.createRequest({
      method: 'GET',
      query: {
        foo: "bar",
        bar: "foo"
      }
  });
  var res = httpMocks.createResponse()
  var fn = middleware.hasOnlyQuery(["foo"])(req, res, function(err){
    expect(err).to.equal("route")
    return done()
  })
})

这是正确的方法吗？有没有办法让这更简单/更容易，或者把它转换成承诺，这样我就可以像承诺的那样使用chai

注意：是一个自定义下划线mixin

---

一种使这一过程更为顺利的方法是创建“下一步”可能有的三种响应

function nextNormal(done){
  return function(err){
    expect(err).to.equal(undefined)
    return done()
  }
}

function nextRoute(done){
  return function(err){
    expect(err).to.equal("route")
    return done()
  }
}

function nextError(done){
  return function(err){
    expect(err).to.be.an('object')
    return done()
  }
}

然后你可以在一行中使用它

middleware.hasOnlyQuery(["foo", "bar"])(req, res, nextNormal(done))

---

将中间件转换为与一起使用的承诺

新测试使用和：

我喜欢这样的测试：

// first test
...
var res = httpMocks.createResponse()
var spy = sinon.spy();
middleware.hasOnlyQuery(["foo"])(req, res, spy);
expect(spy.calledWithExactly()).to.be.true;

// second test
...
expect(spy.calledWithExactly('route')).to.be.true;

it("should fire correct next callback", function(done){
  Promise.all([
    middleware.hasOnlyQuery(["foo"])(reqFoo, res).should.eventually.equal("next"),
    middleware.hasOnlyQuery(["foo", "bar"])(reqFoo, res).should.eventually.equal("route"),
    middleware.hasOnlyQuery(["foo", "alpha"])(reqFoo, res).should.eventually.equal("route"),
    middleware.hasOnlyQuery(["foo"])(reqFooBar, res).should.eventually.equal("route"),
    middleware.hasOnlyQuery(["foo", "bar"])(reqFooBar, res).should.eventually.equal("next"),
    middleware.hasOnlyQuery(["foo", "alpha"])(reqFooBar, res).should.eventually.equal("route")
  ]).then(function(){
    done()
  })
})

// first test
...
var res = httpMocks.createResponse()
var spy = sinon.spy();
middleware.hasOnlyQuery(["foo"])(req, res, spy);
expect(spy.calledWithExactly()).to.be.true;

// second test
...
expect(spy.calledWithExactly('route')).to.be.true;