单元测试 – Angular 2单元测试可观察错误(HTTP)

所有单元测试都与服务引发错误的单元测试分开(由于HTTP状态代码错误).我可以通过退出response.ok告诉我.从我所读到的,这与单元测试没有异步执行有关,因此,不等待错误响应.但是,我不知道为什么会出现这种情况,因为我在beforeEach方法中使用了async()实用程序函数.

API服务

get(endpoint: string,authenticated: boolean = false): Observable<any> {
    endpoint = this.formatEndpoint(endpoint);
    return this.getHttp(authenticated) // Returns @angular/http or a wrapper for handling auth headers
        .get(endpoint)
        .map(res => this.extractData(res))
        .catch(err => this.handleError(err)); // Not in guide but should work as per docs
}
private extractData(res: Response): any {
    let body: any = res.json();
    return body || { };
}

private handleError(error: Response | any): Observable<any> {
    // TODO: Use a remote logging infrastructure
    // TODO: User error notifications
    let errMsg: string;
    if (error instanceof Response) {
        const body: any = error.json() || '';
        const err: string = body.error || JSON.stringify(body);
        errMsg = `${error.status} - ${error.statusText || ''}${err}`;
    } else {
        errMsg = error.message ? error.message : error.toString();
    }
    console.error(errMsg);
    return Observable.throw(errMsg);
}

错误单元测试

// Imports

describe('Service: APIService',() => {
    let backend: MockBackend;
    let service: APIService;

    beforeEach(async(() => {
        TestBed.configureTestingModule({
            providers: [
                BaseRequestOptions,MockBackend,APIService,{
                    deps: [
                        MockBackend,BaseRequestOptions
                    ],provide: Http,useFactory: (backend: XHRBackend,defaultOptions: BaseRequestOptions) => {
                            return new Http(backend,defaultOptions);
                        }
                },{provide: AuthHttp,useFactory: (http: Http,options: BaseRequestOptions) => {
                        return new AuthHttp(new AuthConfig({}),http,options);
                    },deps: [Http,BaseRequestOptions]
                }
            ]
        });
        const testbed: any = getTestBed();
        backend = testbed.get(MockBackend);
        service = testbed.get(APIService);
    }));

    /**
     * Utility function to setup the mock connection with the required options
     * @param backend
     * @param options
     */
    function setupConnections(backend: MockBackend,options: any): any {
        backend.connections.subscribe((connection: MockConnection) => {
            const responSEOptions: any = new ResponSEOptions(options);
            const response: any = new Response(responSEOptions);
            console.log(response.ok); // Will return false during the error unit test and true in others (if spyOn log is commented).
            connection.mockRespond(response);
        });
    }

    it('should log an error to the console on error',() => {
        setupConnections(backend,{
            body: { error: `Some strange error` },status: 400
        });
        spyOn(console,'error');
        spyOn(console,'log');

        service.get('/bad').subscribe(null,e => {
            // None of this code block is executed.
            expect(console.error).toHaveBeenCalledWith("400 - Some strange error");
            console.log("Make sure an error has been thrown");
        });

        expect(console.log).toHaveBeenCalledWith("Make sure an error has been thrown."); // Fails
    });

更新1

当我检查第一个回调时,response.ok未定义.这让我相信setupConnections实用程序有问题.

it('should log an error to the console on error',async(() => {
        setupConnections(backend,'error');
        //spyOn(console,'log');

        service.get('/bad').subscribe(res => {
            console.log(res); // Object{error: 'Some strange error'}
            console.log(res.ok); // undefined
        },e => {
            expect(console.error).toHaveBeenCalledWith("400 - Some strange error");
            console.log("Make sure an error has been thrown");
        });

        expect(console.log).toHaveBeenCalledWith("Make sure an error has been thrown.");
    }));

更新2

如果不是在get方法中捕获错误而是在map中明确地执行它,那么仍然有相同的问题.

get(endpoint: string,authenticated: boolean = false): Observable<any> {
    endpoint = this.formatEndpoint(endpoint);
    return this.getHttp(authenticated).get(endpoint)
        .map(res => {
            if (res.ok) return this.extractData(res);
            return this.handleError(res);
        })
        .catch(this.handleError);
}

更新3

经过一些讨论this issue提交