Angular 角度测试:如何使用测试床向服务类提供配置对象?
我有一个Angular服务,需要将配置对象传递到该服务:Angular 角度测试:如何使用测试床向服务类提供配置对象?,angular,unit-testing,testing,jasmine,Angular,Unit Testing,Testing,Jasmine,我有一个Angular服务,需要将配置对象传递到该服务: // my.module.ts @NgModule({ ... }) export class MyModule { static forRoot(config: MyServiceConfig): ModuleWithProviders { return { ngModule: MyModule, providers: [{ provide: MyServiceCo
// my.module.ts
@NgModule({ ... })
export class MyModule {
static forRoot(config: MyServiceConfig): ModuleWithProviders {
return {
ngModule: MyModule,
providers: [{ provide: MyServiceConfig, useValue: config }],
};
}
}
//my.service.ts
export class MyService {
constructor(private _http: HttpClient, @Optional() config: MyServiceConfig) {
if (config) {
if (!config.attr1) {
throw new Error('You must provide the attr1 to use this Module.');
} else if (!config.attr2) {
throw new Error('You must provide the attr2 to use this Module.');
} else {
this.attr1 = config.attr1;
this.attr2 = config.attr2;
}
} else {
throw new Error(
'You must provide a MyServiceConfig object with the attr1 and the attr2 to use this module.',
);
}
}
}
这一切都是可行的,但是我想写一些测试来为服务提供配置对象。在测试文件中,我在每个之前都有以下,当没有提供config对象时,它会像预期的那样抛出一个错误:
beforeEach(() => {
TestBed.configureTestingModule({
imports: [HttpClientTestingModule],
providers: [FeedbackService],
});
});
但是,当我试图在每次测试之前将其从中移出并放入单个测试时,我无法正确抛出错误。如果完全按照上述方法调用,但在测试中调用,则会:
it('should do something', () => {
TestBed.configureTestingModule({
imports: [HttpClientTestingModule],
providers: [FeedbackService],
});
});
我在try/catch
块中尝试了上述操作,试图捕捉错误,但它给出了一个假阳性。我尝试了expect(()=>{}).tothrower()
和toThrow()
方法,但即使将TestBed.configureTestingModule()
放在expect中的箭头函数中,也无法工作。这样做不会抛出错误
有办法做到这一点吗?另外,是否有方法向服务提供配置对象,以测试它是否将服务属性设置为正确的值?只需为配置对象提供一个值:
describe("FeedbackService", ()=>{
beforeEach(() => {
TestBed.configureTestingModule({
imports: [HttpClientTestingModule],
providers: [FeedbackService]
});
});
describe("when config object is provided", ()=>{
let dummyConfig : Object;
beforeEach(()=>{
dummyConfig = {/* set some properties*/};
TestBed.overrideProvider(MyServiceConfig, {useValue: dummyConfig});
});
it("should not explode", ()=>{
// a test in which the config object is dummyConfig
});
});
});
侧注:我不认为在没有提供令牌值时,用@Optional
和throw装饰配置对象有什么意义。您基本上是在重新实现默认的未提供逻辑。我使用了@Jota.Toledo的一些答案,并对其进行了编辑,以获得以下测试文件:
import { TestBed } from '@angular/core/testing';
import { MyService } from './my.service';
import { MyServiceConfig } from './my-service-config';
describe('MyService', () => {
beforeEach(() => {
TestBed.configureTestingModule({
imports: [HttpClientTestingModule],
providers: [MyService],
});
});
describe('config object provided', () => {
let config: MyServiceConfig;
const attr1 = 'https://my-test-api.test.com';
const attr2 = 'testing';
beforeEach(() => {
config = null;
});
it('should use the values passed in the config for the attr1 and attr2', () => {
config = { attr1, attr2 };
TestBed.overrideProvider(MyService, { useFactory: () => new MyService(null, config) });
const service: MyService = TestBed.get(MyService);
expect(service.attr1).toBe(attr1);
expect(service.attr2).toBe(attr2);
});
it('should throw an error if config object is provided but not the attr1 attribute', () => {
try {
config = { attr1: null, attr2 };
TestBed.overrideProvider(MyService, { useFactory: () => new MyService(null, config) });
const service: MyService = TestBed.get(MyService);
} catch (e) {
expect(e.message).toBe('You must provide the api URL to use this module.');
}
});
it('should throw an error if config object is provided but not the attr2 attribute', () => {
try {
config = { attr1, attr2: null };
TestBed.overrideProvider(MyService, { useFactory: () => new MyService(null, config) });
const service: MyService = TestBed.get(MyService);
} catch (e) {
expect(e.message).toBe('You must provide the feedback source to use this module.');
}
});
});
describe('config object not provided', () => {
beforeEach(() => {
TestBed.overrideProvider(MyService, { useFactory: () => new MyService(null, null) });
});
it('should throw an error if no config object provided', () => {
try {
const service: MyService = TestBed.get(MyService);
} catch (e) {
expect(e.message).toBe(
'You must provide a MyServiceConfig object with the attr1 and the attr2 to use this module.',
);
}
});
});
});
这正确地抛出了应该抛出的错误,并且我能够检查message属性以确保它在正确的时间抛出了正确的错误。我尝试了您的解决方案,但仍然得到相同的错误。关于@可选的
装饰器,您有一个很好的观点。我读过的所有教程都有,我不确定如何要求它,但是删除decorator似乎会给我同样的错误,所以我确实删除了它。以下工作:TestBed.overrideProvider(FeedbackService,{useFactory:()=>newfeedbackservice(null,config)})代码>我为HttpClient传递了null,因为我没有测试HTTP调用。您如何用可注入的?介意添加这部分代码吗?我不喜欢你目前的做法。