Angular2 RC5如何正确配置测试模块 [英] Angular2 RC5 how to properly configure test module

问题描述

我正在更新Angular2 RC5的单元测试. 更改日志指出以下重大更改:

I'm updating my unit tests for Angular2 RC5. The changelog notes the following breaking change:

addProviders [已弃用]，请改用TestBed.configureTestingModule

addProviders [is deprecated], use TestBed.configureTestingModule instead

但是，这似乎仅在尝试将服务包含在测试中时才会出错.我的单元测试曾经用来执行以下操作:

But this seems to take error only when attempting to include a service in a test. Where my unit test used to do the following:

beforeEach(() => addProviders([
    MyService,
    MockBackend,
    ... 
]));

现在应该配置测试模块:

it should now configure the test module:

TestBed.configureTestingModule({
    providers: [
        StoryService,
        MockBackend,
        ...
    ]
});

但是现在会引发错误

Service:MyService遇到声明异常FAILED

Service: MyService encountered a declaration exception FAILED

错误:已经实例化测试模块时，无法配置测试模块.确保在TestBed.configureTestingModule之前没有使用inject.

Error: Cannot configure the test module when the test module has already been instantiated. Make sure you are not using inject before TestBed.configureTestingModule.

我检查了configureTestingModule之前没有调用inject.这不会影响任何其他组件/指令测试，它们似乎可以通过.使用RC5对服务进行单元测试时，如何解决此错误?我意识到我可能必须等到为RC5更新测试文档后，对任何可能的解决方案的见解将不胜感激.

I have checked that inject isn't been called before the configureTestingModule. This doesn't affect any other component/directive tests, they seem to pass just fine. How can I resolve this error for unit testing a service with RC5? I realize that I may have to wait until the the testing documentation are updated for RC5 but any insight into possible solutions would be much appreciated.

推荐答案

据我所读，您只需初始化测试环境一次.然后，您可以重置测试模块并在每次测试之前配置测试模块:

From what I have read, you only need to init the test environment once. You can then reset the testing module and configure the testing module before each test:

beforeEach(() => {
        TestBed.configureTestingModule({
            declarations: [ GridComponent ]
        });
    });

    afterEach(() => {
        TestBed.resetTestingModule();
    });

前期配置是:

var testing = require('@angular/core/testing');
var browser = require('@angular/platform-browser-dynamic/testing');

try {
    testing.TestBed.initTestEnvironment(browser.BrowserDynamicTestingModule, browser.platformBrowserDynamicTesting());
} catch ($error) {
    console.log("test env failure" + $error);
}

通读代码后，configureTestingModule似乎会在内部调用resetTestingModule，但出于可读性考虑，我希望在每次声明之后都将其声明.

After reading through the code it seems configureTestingModule will call resetTestingModule internally but I like to declare it in after each for readability purposes.

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