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I'm trying to write some qunit unit tests for my knockout view models and I've run into an interesting issue.

In my view model I have the following function:

    Get = function (id) {
        return $.ajax({
            url: API + "/" + id,
            type: 'GET',
            dataType: 'json',
            timeout: Timeout,
            statusCode: {
                200: GetOneSuccess,
                404: ItemNotFound
            },
            error: function () {
                //Item(null);
            }
        });
    },

Then in my unit test I have this:

vm.Get(vm.Item().Id()).then(function () {                    
   ok(false, "Failure!");
},function () {
   equal(vm.Item(), null, "Item was removed");
   start();
});

ItemNotFound is as follows:

    ItemNotFound = function () {
        Item(null);
    }

This is pretty straight forward, if the API controller returns "NotFound (Error 404)" set the Item to null. I am finding that my test if failing because when "then" is called the ItemNotFound function has not completed yet.

If I add a timeout to my unit test, it works:

            vm.Get(vm.Item().Id()).then(function () {                    
                    ok(false, "Failure!");
            },function () {
                    setTimeout(function () {
                        equal(vm.Item(), null, "Item was removed");
                        start();
                    }, 2000);
            });

Anyone have any thoughts? Should I just not bother with the statusCodes and just handle all error types in the error handler? Doesn't seem as elegant.

4

1 回答 1

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在触发状态代码函数之前首先触发错误处理程序。“then”函数接受“成功回调”和“错误回调”。所以本质上，你的错误（失败）是在状态码“notfound”触发之前触发的。

当您设置超时时，该函数会立即返回，触发您的状态代码，然后根据您设置的超时，触发该特定代码。

如果您仍然想要现有的代码结构，那么这就是我的做法。您的 GET 函数应该返回一个封装了实际 ajax 调用的延迟承诺对象，并且不指定成功或错误处理程序，并首先从您的 statusCode 调用您的成功或错误函数。

我为此创建了一个小提琴

http://jsfiddle.net/sujesharukil/BWA9D/15/

var data = {
    json: $.toJSON({
        text: 'some text',
        array: [1, 2, 'three'],
        object: {
            par1: 'another text',
            par2: [3, 2, 'one'],
            par3: {}
        }
    })
}


var callEcho = function(url) {
    return $.Deferred(function(def){
        $.ajax({
        url: url,
        type: "POST",
        data: data,
        statusCode: {
            200: function(data,xhr){
                GetOneSuccess();
                def.resolve(data);
            },
            404: function(xhr){
                ItemNotFound();
                def.reject();
            }
        }
    });    
}).promise();

};

function GetOneSuccess(){
    alert('Get One success Called');
}

function ItemNotFound(){
    alert('Item Not Found Called');
}

var testFunc = function(url){
    var js = callEcho(url);
    js.done(function(data){
        alert(JSON.stringify(data) + ' done function called');
    });

    js.fail(function(){
        alert('fail function called.');
    });
}

//fire the success
testFunc("/echo/json/" );

//fire the fail
testFunc("/echo/jso/");
于 2013-03-11T13:37:05.610 回答