监视茉莉花中的jQuery $(' ...')选择器 [英] Spying on jQuery $('...') selector in jasmine

问题描述

在监视jQuery函数(例如 bind ， click 等)时，很容易:

  spyOn($.fn，"bind"); 

问题是当您想监视 $('...')并返回定义的元素数组时.

在阅读有关SO的其他相关答案后尝试过的事情:

  spyOn($.fn，"init").andReturn(elements);//工作正常，但会破坏afterEach()等中使用jQuery选择器的内容spyOn($.fn，"merge").andReturn(elements);//合并功能似乎在jQuery 1.9.1中不存在spyOn($.fn，"val").andReturn(elements);//函数永远不会被调用 

那我该怎么做呢?或者，如果唯一的方法是监视 init 函数，那么完成后如何从函数中删除"间谍，以使 afterEach()路由不会中断./p>

jQuery版本是1.9.1.

解决方法:

到目前为止(我很难做到)，这是我唯一的方法:

  realDollar = $;尝试 {$ = jasmine.createSpy("dollar").andReturn(elements);//测试代码并断言此处} 最后 {$ = realDollar;} 

解决方案

通常，在规格有效期内存在间谍.但是，销毁间谍没有什么特别的.您只需恢复原始函数引用即可.

这里有一个方便的小助手功能(带有一个测试用例)，它将清理您的解决方法并使其更有用.在 afterEach 中调用 unspy 方法以恢复原始引用.

  function spyOn(obj，methodName){var original = obj [methodName];var spy = jasmine.getEnv().spyOn(obj，methodName);spy.unspy = function(){如果(原始){obj [methodName] =原始；原始= null;}};返回间谍}describe("unspy"，function(){it(删除间谍"，function(){var mockDiv = document.createElement("div");var mockResult = $(mockDiv);spyOn(window，"$").and.returnValue(mockResult);Expect($(document.body).get(0)).toBe(mockDiv);$ .unspy();Expect(jasmine.isSpy($)).toEqual(false);Expect($(document.body).get(0)).toBe(document.body);});}); 

作为上述替代方法(以及对所有其他阅读此方法的人而言)，您可以更改解决问题的方式.与其侦听 $ 函数，不如尝试将对 $ 的原始调用提取到其自己的方法中，并以此侦听.

 //原始myObj.doStuff = function(){$(#someElement").css("color"，"red");};//变成...myObj.doStuff = function(){this.getElements().css("color"，"red");};myObj.getElements = function(){返回$(#someElement");};//测试用例it("does stuff"，function(){spyOn(myObj，"getElements").and.returnValue($(/*模拟元素*/));//...}); 

When it comes to spying on jQuery functions (e.g. bind, click, etc) it is easy:

spyOn($.fn, "bind");

The problem is when you want to spy on $('...') and return defined array of elements.

Things tried after reading other related answers on SO:

spyOn($.fn, "init").andReturn(elements); // works, but breaks stuff that uses jQuery selectors in afterEach(), etc
spyOn($.fn, "merge").andReturn(elements); // merge function doesn't seem to exist in jQuery 1.9.1
spyOn($.fn, "val").andReturn(elements); // function never gets called

So how do I do this? Or if the only way is to spy on init function how do I "remove" spy from function when I'm done so afterEach() routing doesn't break.

jQuery version is 1.9.1.

WORKAROUND:

The only way I could make it work so far (ugly):

realDollar = $;
try {
  $ = jasmine.createSpy("dollar").andReturn(elements);
  // test code and asserts go here
} finally {
  $ = realDollar;
}

解决方案

Normally, a spy exists for the lifetime of the spec. However, there's nothing special about destroying a spy. You just restore the original function reference and that's that.

Here's a handy little helper function (with a test case) that will clean up your workaround and make it more usable. Call the unspy method in your afterEach to restore the original reference.

function spyOn(obj, methodName) {
    var original = obj[methodName];
    var spy = jasmine.getEnv().spyOn(obj, methodName);
    spy.unspy = function () {
        if (original) {
            obj[methodName] = original;
            original = null;
        }
    };
    return spy;
}

describe("unspy", function () {
    it("removes the spy", function () {
        var mockDiv = document.createElement("div");
        var mockResult = $(mockDiv);

        spyOn(window, "$").and.returnValue(mockResult);
        expect($(document.body).get(0)).toBe(mockDiv);

        $.unspy();

        expect(jasmine.isSpy($)).toEqual(false);
        expect($(document.body).get(0)).toBe(document.body);
    });
});

As an alternative to the above (and for anyone else reading this), you could change the way you're approaching the problem. Instead of spying on the $ function, try extracting the original call to $ to its own method and spying on that instead.

// Original
myObj.doStuff = function () {
    $("#someElement").css("color", "red");
};

// Becomes...
myObj.doStuff = function () {
    this.getElements().css("color", "red");
};

myObj.getElements = function () {
    return $("#someElement");
};

// Test case
it("does stuff", function () {
    spyOn(myObj, "getElements").and.returnValue($(/* mock elements */));
    // ...
});

这篇关于监视茉莉花中的jQuery $(' ...')选择器的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！