我正在使用NgRx ^ 7.0.0版本。 这是我的NgRx效果类:
import { Injectable } from '@angular/core';
import { ApisService } from '../apis.service';
import { Effect, Actions, ofType } from '@ngrx/effects';
import { Observable } from 'rxjs';
import { ApisActionTypes, ApisFetched } from './apis.actions';
import { mergeMap, map } from 'rxjs/operators';
@Injectable()
export class ApisEffects {
constructor(private apisS: ApisService, private actions$: Actions) { }
@Effect()
$fetchApisPaths: Observable<any> = this.actions$.pipe(
ofType(ApisActionTypes.FetchApisPaths),
mergeMap(() =>
this.apisS.fetchHardCodedAPIPaths().pipe(
map(res => new ApisFetched(res))
)
)
);
}
那是一个简单的测试。如您所见,它应该会失败,但总是会失败。 我在这里在StackOverflow How to unit test this effect (with {dispatch: false})?上遵循了类似的问题,但是它对我不起作用,就好像代码执行从未进入效果。$ fetchApisPaths.subscribe块
import { TestBed } from '@angular/core/testing';
import { provideMockActions } from '@ngrx/effects/testing';
import { hot, cold } from 'jasmine-marbles';
import { Observable, ReplaySubject } from 'rxjs';
import { ApisEffects } from '../state/apis.effects';
import { ApisFetch, ApisFetched } from '../state/apis.actions';
import { IApiPath } from '../models';
import { convertPaths, getAPIPathsAsJson, ApisService } from '../apis.service';
import { ApisServiceMock } from './mocks';
describe('Apis Effects', () => {
let effects: ApisEffects;
let actions: Observable<any>;
let apisS: ApisService;
beforeEach(() => {
TestBed.configureTestingModule({
providers: [
ApisEffects,
provideMockActions(() => actions),
{
provide: ApisService,
useClass: ApisServiceMock
}
]
});
effects = TestBed.get(ApisEffects);
apisS = TestBed.get(ApisService);
});
it('should call ApisService method() to get Api Paths', () => {
const spy = spyOn(apisS, 'fetchHardCodedAPIPaths');
const action = new ApisFetch();
actions = hot('--a-', {a: action});
effects.$fetchApisPaths.subscribe(() => {
console.log('%c effect trigerred', 'color: orange; border: 1px solid red;');
// expect(spy).toHaveBeenCalled();
expect(true).toBe(false); // never fails
});
});
});
以防万一我对动作做傻了,这是动作文件: 我很可能不是,因为它可以按预期在应用中运行。
import { Action } from '@ngrx/store';
import { IApiPath } from '../models';
export enum ApisActionTypes {
FetchApisPaths = '[Apis] Fetch Paths',
FetchedApisPaths = '[Apis] Fetched Paths'
}
export class ApisFetch implements Action {
readonly type = ApisActionTypes.FetchApisPaths;
}
export class ApisFetched implements Action {
readonly type = ApisActionTypes.FetchedApisPaths;
constructor(public payload: IApiPath[]) {}
}
export type ApisActions = ApisFetch | ApisFetched;
================================================= =======
我已经使用了来自ngrx官方文档https://ngrx.io/guide/effects/testing的示例,现在我可以成功在下面输入subscription块,同时记录了两个控制台日志,但是测试成功。真奇怪我尝试从订阅块抛出错误,但测试仍然成功。
it('should work also', () => {
actions$ = new ReplaySubject(1);
actions$.next(new ApisFetch());
effects.$fetchApisPaths.subscribe(result => {
console.log('will be logged');
expect(true).toBe(false); // should fail but nothing happens - test succeeds
console.log(' --------- after '); // doesn't get called, so the code
// execution stops on expect above
});
});
答案 0 :(得分:3)
好,所以我知道了。为了成功测试是否从NgRx效果中调用了特定的Angular服务方法,我将测试用例包装在async
中:
it('should call ApisService method to fetch Api paths', async () => {
const spy = spyOn(apisS, 'fetchHardCodedAPIPaths');
actions$ = new ReplaySubject(1);
actions$.next(new ApisFetch());
await effects.$fetchApisPaths.subscribe();
expect(spy).toHaveBeenCalled();
});
我await effects.$fetchApisPaths.subscribe();
阻止执行并在下一行运行测试断言。
现在,当我尝试运行expect(true).toBe(false);
来测试测试是否失败时,它会正确地失败。
问题中我的代码存在问题(例如在ngrx docs https://ngrx.io/guide/effects/testing中使用ReplaySubject
的示例)是,当断言位于.subscribe()
中时,无法通过测试块。那里有些杂乱无章的事,我仍然不知道为什么代码会以以下方式表现:
effects.$fetchApisPaths.subscribe(result => {
console.log('will be logged'); // 1) gets logged
expect(true).toBe(false); // 2) should fail
console.log(' - after '); // 3) doesn't get called
});
因此代码执行在第 2)行停止,测试用例返回正数,而在第 3)行永不执行。
因此,在.subscribe()
块内有断言的ngrx docs中的测试用例将始终为绿色,从而给您的测试用例带来了误判。这是我在ngrx ^7.0.0