Jasmine 存根函数导致类型错误“...不是函数”

Question

我正在尝试从我的测试中的“NavigationService”存根一个函数。

正如您在下面看到的，我想使用 NavigationServiceStub 而不是 NavigationService。 NavigationService 有一个名为“configureTargetScreensForNetworkConfiguration”的方法，我在存根中对其进行了模拟。

使用此设置我收到错误 TypeError: this.navigationService.configureTargetScreensForNetworkConfigurationis not a function。我错过了什么吗？

describe('NetworkDevicesComponent', () => {
...
    beforeEach(waitForAsync(() => {
        networkServiceSpy = jasmine.createSpyObj('NetworkService', ['getNetworkDevices']);
        networkServiceSpy.getNetworkDevices.and.returnValue(
            of([
                {type: NetworkType.WLAN, state: NetworkState.CONNECTING, links: null}
            ])
        );


        TestBed.configureTestingModule({
            declarations: [
                NetworkDevicesComponent
            ],
            imports: [
                RouterTestingModule
            ],
            providers: [
                {provide: NetworkService, useValue: networkServiceSpy},
                {provide: NavigationService, useValue: NavigationServiceStub}
            ]
        }).compileComponents();
    }));
...

@Injectable()
export class NavigationService {
...

    public configureTargetScreensForNetworkConfiguration(params: ParamMap): void {
        if (this.hasNetworkTargetScreenParams(params)) {
            this.setTargetScreensForNetworkConfiguration(params.get('backwardUrl'), params.get('forwardUrl'));
            this.staticNetworkNavigationEnabled = true;
        } else {
            this.setTargetScreensForNetworkConfiguration('../../', '../../network-devices');
            this.staticNetworkNavigationEnabled = false;
        }

        console.log('configured network-setting urls with backwardUrl:', this.targetScreenBeforeNetworkConfiguration,
            'forwardUrl:', this.targetScreenAfterNetworkConfiguration,
            'static-routing:', this.staticNetworkNavigationEnabled);

    }
...
}

export class NavigationServiceStub {

    configureTargetScreensForNetworkConfiguration(params: ParamMap): void {
    }
...
}

Answer 1

由于存根是 class，我认为您应该使用 useClass 而不是 useValue 作为存根。

尝试：

providers: [
                {provide: NetworkService, useValue: networkServiceSpy},
                // change the line below to do useClass instead of useValue
                {provide: NavigationService, useClass: NavigationServiceStub}
            ]

Jasmine 存根函数导致类型错误“...不是函数”

Jasmine stubbed function results to an type error "... is not a function"

jasmine

karma-jasmine

angular