Jasmine:如何监视内部对象方法调用？

Question

我有两个我要测试的原型:

var Person = function() {};

Person.prototype.pingChild = function(){
   var boy = new Child();
   boy.getAge();
}

var Child = function() {};

Child.prototype.getAge = function() {
    return 42;
};

我究竟要测试的是:检查getAge()方法内部是否调用该pingChild()方法

这是我试图用于此目的的Jasmine规范:

describe("Person", function() {
    it("calls the getAge() function", function() {
        var fakePerson = new Person();
        var chi = new Child();
        spyOn(fakePerson, "getAge");
        fakePerson.pingChild();
        expect(chi.getAge).toHaveBeenCalled();
    });
});

describe("Person", function() {
    it("calls the getAge() function", function() {
        var fakePerson = new Person();
        spyOn(fakePerson, "getAge");
        fakePerson.pingChild();
        expect(fakePerson.getAge).toHaveBeenCalled();
    });
});

describe("Person", function() {
    it("calls the getAge() function", function() {
        var fakePerson = new Person();
        var chi = new Child();
        spyOn(chi, "getAge");
        fakePerson.pingChild();
        expect(chi.getAge).toHaveBeenCalled();
    });
});

但所有这些都只显示错误:

• getAge()方法不存在
• getAge()方法不存在
• 已经调用了预期的间谍getAge

那么,有没有办法用Jasmine测试这样的情况,如果是的话 - 怎么办呢？

Answer 1

你对Child对象的原型有间谍.

describe("Person", function () {
  it("calls the getAge() function", function () {
    var spy = spyOn(Child.prototype, "getAge");
    var fakePerson = new Person();
    fakePerson.pingChild();
    expect(spy).toHaveBeenCalled();
  });
});