依赖注入在单元测试未定义 [英] Injected Dependency is undefined in Unit Test

问题描述

我新的角度，我不太清楚究竟是如何依赖注入的作品。我的问题是，我有一个服务依赖于服务B，但是当我注入服务A到我的测试服务B是不确定的。

I'm new to Angular and I'm not quite sure exactly how dependency injection works. My problem is that I have Service A which depends on Service B, but when I inject Service A into my test Service B becomes undefined.

我见过<一个href=\"http://stackoverflow.com/questions/14238490/injecting-dependent-services-when-unit-testing-angularjs-services\">Injecting相关的服务时，单元测试AngularJS服务但这个问题比我有点不同。

I have seen Injecting dependent services when unit testing AngularJS services but that problem is a bit different than mine.

这<一个href=\"http://stackoverflow.com/questions/33788405/injected-dependencies-become-undefined-in-angular-service\">Injected依赖成为角服务 undefined是非常相似，我的问题，但我无法翻译JS。

This Injected Dependencies become undefined in angular service is very similar to my issue but I couldn't translate the JS.

我也改变了我的变量名和简化了code去除不相关的线。

I have also changed my variable names and simplified the code to remove irrelevant lines.

Service.ts

export class ServiceA {
    constructor(private $resource: ng.resource.IResourceService, private ServiceBInstance: ServiceB){
    }

    ServiceAMethod() {
        var resources = ServiceBInstance.property;  //ServiceBInstance is undefined here
    }
}

factory.$inject = [
    '$resource'
    'ServiceBModule'
];
function factory($resource: ng.resource.IResourceService, ServiceBInstance: ServiceB): IServiceA {
    return new ServiceA($resource, ServiceBInstance);
}

angular
    .module('ServiceAModule')
    .factory('ServiceA',
    factory);

Spec.ts

describe('ServiceB', (): void => {

    beforeEach((): void => {
        angular.mock.module(
            'ServiceAModule',
            'ServiceBmodule',
            'ngResource'
        );
    });

    describe('ServiceAMethod', (): void => {

        it("should...", inject(
            ['ServiceA', (ServiceAInstance: ServiceA): void => {
                ServiceAInstance.ServiceAMethod(); //Problem Here
            }]));
    });

}）;

我遇到的问题是，当我叫ServiceAMethod我得到它规定的错误类型错误：无法读取属性未定义的财产。奇怪的事情是，$资源从来都不是不确定的，但我的ServiceB始终是不确定的。

The problem I'm having is that when I call ServiceAMethod I get an error which states "TypeError: Cannot read property 'property' of undefined". The weird thing is that $resource is never undefined but my ServiceB is always undefined.

我认为，当我注入ServiceA到我的测试中它会自动注入也是其所有依赖。

I thought that when I inject ServiceA into my test it should automatically also inject all of its dependencies.

另外请注意，我不是故意的嘲笑ServiceB。

Also note that I am not mocking ServiceB on purpose.

更新

我也试过注入我ServiceB的一个实例到它但是当我打印出来的变量还指出，它是不确定的，而当我尝试做$ C低于$ C到 beforeEach

I've also tried to inject an instance of my ServiceB into the it but when I print out the variable it also states that is it undefined, and when I try to to do the code below into the beforeEach

inject(function (_ServiceBInstance_: ServiceB) {
        console.log(_ServiceBInstance_);
    });

我得到和未知提供商错误

推荐答案

好了，所以搜索了几个小时之后，我终于找到了答案。我忘了，包括其中包含的文件角的.config方法

Ok so after hours of searching I finally found the answer. I forgot to include a file which included Angular's .config method

在创建供应商确保你也呼吁的.config，这里有一个例子：

When creating the provider make sure that you also call .config, here's an example:

angular
    .module('ServiceBModule')
    .config(['ServiceBProvider', (ServiceBClass) => { //Very Important
        //Code here
    }])
    .provider('ServiceB', ServiceB);

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