How to marble test ngrx effect - unit-testing

I have the following ngrx effect
#Injectable()
export class StoreEffects {
constructor(
private store: Store<State>,
private actions$: Actions,
) { }
#Effect()
userProfile$ = this.actions$
.ofType('Load')
.switchMap(action => {
const payLoad = action['payload'];
//Run code to load here
return Observable.of({}); //Just for clarity I have simplified
});
}
Now I want to unit test this, and came across the following documentation
https://github.com/ngrx/platform/blob/master/docs/effects/testing.md
By following the documentation I came up with the following spec
beforeEach(() => {
TestBed.configureTestingModule({
imports: [
HttpClientModule,
StoreModule.forRoot({}) //I'm not sure why you need this, but if I dont supply this it does not work
],
providers: [
ProfileEffects,
provideMockActions(() => actions),
],
});
});
it('should work', async () => {
actions = hot('-a|', { a: {type: 'Load'}} });
console.log('testing');
});
});
Now from what I understand whey I run the spec it should invoke my effect, but nothing happens and the test just runs to completion. What am I doing wrong here?
I'm using Jamine.

Related

How to test NestJS Controller if it has a lot of dependent services?

I have a trouble with Testing Nest JS Controller because I cannot realise how to make a Testing Module with all the dependencies. I've already tried Mocks but still it's not working.
Here's how the controller I want to test looks like
calculator.controller.ts
#Controller('/calculator')
export class CalculatorController {
constructor(
#Inject(HISTORY_SERVICE)
private historyService: HistoryService,
#Inject(CACHE_SERVICE)
private readonly cacheService: CacheService,
#Inject(CALCULATOR_SERVICE)
private readonly calculatorService: CalculatorService,
) {}
#Get()
getResult(#Query() expressionDto: ExpressionDto): Promise<ClientResponseDto> {
const expression: string = expressionDto.expression;
const response: Promise<ClientResponseDto> = this.cacheService
.checkInCache(expression)
.then((response) => {
if (!response) {
const calculationResult =
this.calculatorService.getResult(expression);
const clientDto = this.historyService
.create({
expression,
result: calculationResult,
})
.then((dbResponse) => {
return this.cacheService.setToCache(dbResponse);
});
return clientDto;
}
return this.historyService.create({ expression, result: response });
});
return response;
}
}
And this is how it's spec looked like before mocks implementation
controller.spec.ts
let calculatorController: CalculatorController;
let calculatorService: CalculatorService;
beforeEach(async () => {
const moduleRef = await Test.createTestingModule({
imports: [HistoryModule],
controllers: [CalculatorController],
providers: [
CalculatorService,
],
})
.useMocker(() => createMock())
.compile();
calculatorController =
moduleRef.get<CalculatorController>(CalculatorController);
calculatorService = moduleRef.get<CalculatorService>(CalculatorService);
jest.clearAllMocks();
});
describe('Calculator Controller', () => {
it('should be defined', () => {
expect(calculatorController).toBeDefined();
});
it('should have all methods', () => {
expect(calculatorController.getResult).toBeDefined();
expect(calculatorController.getResult(calculatorStub().request)).toBe(
typeof Promise,
);
});
});
And this test failed when calling getResult function cause inside this Function firstly I call CacheService to check data in Cache. So at this moment test failed telling that
TypeError: this.cacheService.checkInCache(...).then is not a function
24 | const response: Promise<ClientResponseDto> = this.cacheService
25 | .checkInCache(expression)
> 26 | .then((response) => {
| ^
I started to think that the problem is Testing module somehow doesn't have access to the Cache Service, so I added mock to the providers like this
let calculatorController: CalculatorController;
let calculatorService: CalculatorService;
beforeEach(async () => {
const moduleRef = await Test.createTestingModule({
imports: [HistoryModule],
controllers: [CalculatorController],
providers: [
CalculatorService,
{
provide: CacheService,
useValue: {
checkInCache: jest.fn().mockResolvedValue(Promise<null>),
},
},
],
})
.useMocker(() => createMock())
.compile();
calculatorController =
moduleRef.get<CalculatorController>(CalculatorController);
calculatorService = moduleRef.get<CalculatorService>(CalculatorService);
jest.clearAllMocks();
});
But now tests don't even run cause I have Nest dependencies problems
Nest can't resolve dependencies of the CalculatorController (HISTORY_SERVICE, ?,
CALCULATOR_SERVICE). Please make sure that the argument dependency at index [1] is
available in the RootTestModule context.
What is the issue and how is it possible to solve this problem?
Generally speaking, when unit testing a service or a controller, you want to provide mocks for the controller's or service's dependencies. Most of the time, these are going to be objects with the same method names but the methods are set to be jest.fn() or similar for other mock libraries. You'll want to use custom providers to create the mock providers that will be injected. Taking your controller above, you'll want the setup of your test to look something like this:
describe('CaclulatorController', () => {
let controller: CalculatorController;
let service: Pick<jest.MockedObject<CalculatorService>, 'getResult'>;
let cache: Pick<jest.MockedObject<CacheService>, 'checkInCache' | 'setToCache'>;
let history: Pick<jest.MockedObject<HistoryService>, 'create'>;
beforeAll(async () => {
const modRef = await Test.createTestModule({
controller: [CalculatorController],
providers: [
{
provide: CALCULATOR_SERVICE,
useValue: {
getResult: jest.fn(),
},
},
{
provide: CACHE_SERVICE,
useValue: {
checkInCache: jest.fn(),
setToCache: jest.fn(),
},
},
{
provide: HISTORY_SERVICE,
useValue: {
create: jest.fn(),
},
},
]
}).compile();
controller = app.get(CalculatorController);
service = app.get(CALCULATOR_SERVICE);
cache = app.get(CACHE_SERVICE);
history = app.get(HISTORY_SERVICE);
});
Okay that's a lot to look at at once, so let's step through the big parts and explain what's going on here. The first this I do is set up local variables to reference during the test for the class that I'm testing (CalculatorController) and the dependencies of the class so I can modify them as necessary. Next, I use a Pick<T, K> generic with the jest.MockedOject<T> generic to tell Typescript that "This class has been mocked by jest, and I only am worried about these methods of it" so later on when I use cache. I'll get some intellisense for the checkInCache and setToCache methods, and they'll have jest's mock function types.
In the beforeAll I set up the initial mocks for the dependencies, you can also set return values here using the appropriate mockReturnValue or mockResolvedValue methods.
Now that the mocks and dependencies are set up, we can actually write a test. My approach is to use a describe block per method and its per variation of the method's outcome and branches. I'll write a single branch to show you and let you work out the rest from there.
describe('getResult', () => {
it('should get no response from the cache and perform a full caclulation', async () => {
cache.checkInCache.mockResolvedValueOnce(undefined);
service.getResult.mockResolvedValueOnce(calculationResult);
histoy.create.mockResolvedValueOnce(dbResult);
cache.setInCache.mockResolvedValueOnce(cacheSaveResult);
await expect(controller.getResult({ expression: someExpression })).resolves.toEqual(cacheSaveResult)
});
})
This should cover the case where there's no value in the cache and the full set of steps has to be taken. By using mockResolvedValueOnce we ensure that the methods don't return if called more than once as that's most likely not the expected case here, and we're making sure to return promsies as you use .thens. You might want to look into async/await syntax to help clean that up.
putting the two snippets together we have the following:
describe('CaclulatorController', () => {
let controller: CalculatorController;
let service: Pick<jest.MockedObject<CalculatorService>, 'getResult'>;
let cache: Pick<jest.MockedObject<CacheService>, 'checkInCache' | 'setToCache'>;
let history: Pick<jest.MockedObject<HistoryService>, 'create'>;
beforeAll(async () => {
const modRef = await Test.createTestModule({
controller: [CalculatorController],
providers: [
{
provide: CALCULATOR_SERVICE,
useValue: {
getResult: jest.fn(),
},
},
{
provide: CACHE_SERVICE,
useValue: {
checkInCache: jest.fn(),
setToCache: jest.fn(),
},
},
{
provide: HISTORY_SERVICE,
useValue: {
create: jest.fn(),
},
},
]
}).compile();
controller = app.get(CalculatorController);
service = app.get(CALCULATOR_SERVICE);
cache = app.get(CACHE_SERVICE);
history = app.get(HISTORY_SERVICE);
});
describe('getResult', () => {
it('should get no response from the cache and perform a full caclulation', async () => {
cache.checkInCache.mockResolvedValueOnce(undefined);
service.getResult.mockResolvedValueOnce(calculationResult);
histoy.create.mockResolvedValueOnce(dbResult);
cache.setInCache.mockResolvedValueOnce(cacheSaveResult);
await expect(controller.getResult({ expression: someExpression })).resolves.toEqual(cacheSaveResult)
});
});
});
That should be enough to get you started on testing the rest of your controller. If you need more test setup examples, there's an entire GitHub repository of them with different setups

Angular8 Unittest Router Events

I am trying to test my router event this is what te code in the TS file look like:
constructor(
private router: Router
) {
router.events.subscribe(route => {
// I removed the code because it doesn`t matter for the solution
});
}
unittest:
describe('MainComponent', () => {
let methodSpy: jasmine.Spy;
const eventSubject = new ReplaySubject<RouterEvent>(1);
const routerMock = {
navigate: jasmine.createSpy('navigateByUrl'),
navigateByUrl: jasmine.createSpy('navigateByUrl'),
events: eventSubject.asObservable(),
url: 'test/url',
createUrlTree: (commands, navExtras = {}) => {},
serializeUrl: (commands, navExtras = {}) => {}
}
beforeEach(async(() => {
TestBed.configureTestingModule({
imports: [RouterTestingModule, FormsModule],
declarations: [],
providers: [
{ provide: Router, useValue: routerMock},
{ provide: ActivatedRoute, useValue: routerMock},
]
})
.compileComponents();
}));
beforeEach(() => {
fixture = TestBed.createComponent(MainComponent);
component = fixture.componentInstance;
methodSpy = spyOn(component, 'AdminPanelStarted');
//fixture.detectChanges();
});
it('should trigger the router event and hit the function "Panel"', () => {
eventSubject.next(new NavigationEnd(1, 'test', 'routeUrl'));
expect(methodSpy).toHaveBeenCalled();
});
});
this is the error I am getting:
I can`t find the solution. The only thing I want to test is if the correct function have been called after entering the router.events subscription. The observable is triggered but gives the error that startsWith can not be done on undefined. But what is undefined?
Thx a Lot!

How to handle bootstrap-daterangepicker in angular component unit test?

I am trying to write a unit test of an angular 6 component which is initializing the bootstrap-daterangepicker in the ngAfterViewInit() method. When I run my unit test it gives the following error:
TypeError: $(...).daterangepicker is not a function
this is the code from the actual component(EmployeeComponent):
ngAfterViewInit(): void {
this.initializeDatePicker(this);
}
initializeDatePicker(that: any) {
const start = moment().subtract(7, 'days');
const end = moment();
$('#reportrange').daterangepicker({
startDate: start,
endDate: end,
maxDate: moment(),
ranges: {
'Today': [moment(), moment()],
'Yesterday': [moment().subtract(1, 'days'), moment().subtract(1, 'days')]
}
}, cb);
cb(start, end);
}
this is the code from my test class:
describe('EmployeeComponent', () => {
let component: EmployeeComponent;
let fixture: ComponentFixture<EmployeeComponent>;
let messageService: NotificationService;
beforeEach(async(() => {
TestBed.configureTestingModule({
declarations: [EmployeeComponent]
})
.overrideComponent(EmployeeComponent, {
set: {
template: '',
providers: [
{ provide: NotificationService, useValue: messageService },
{ provide: ActivatedRoute, useValue: { queryParams: of({ emp: "123" }) } }
]
}
})
.compileComponents();
}));
beforeEach(() => {
fixture = TestBed.createComponent(EmployeeComponent);
component = fixture.componentInstance;
fixture.detectChanges();
});
it('should create', () => {
expect(component).toBeTruthy();
});
You don't need to handle it in your test cases. That component should be initialized in a separate service and you can simply mock that method from the service. In the way you can avoid this error.
let say you move all the code of the initializeDatePicker() in a method in some service let say common-service.ts and you can simply call that service from this method like
this.commonServiceObj.initializeDatePicker();
Now after doing this, you can simply mock initializeDatePicker() from the service object and error should be gone.

Angular2, jasmine: Component changes not seen in test spec function

I'm still writing tests for my Angular app. I've a test that modifies an Org object, saves the changes, and then proves that the changes have been kept. However, the test isn't seeing the changes.
My mock Org service that saves the changes:
#Injectable()
export class MockOrgService {
constructor() { }
public save(org: Org): Observable<Org> {
let savedOrg: Org = new Org(org);
savedOrg.address2 = 'Saved with id: ' + org.id;
return Observable.of(savedOrg);
}
}
My mock router:
beforeEach(async(() => {
routeStub = { data: Observable.of( { org: org1 } ), snapshot: {} } ;
TestBed.configureTestingModule({
imports: [ FormsModule, RouterTestingModule ],
providers : [
{ provide: DialogService, useClass: MockDialogService },
{ provide: GlobalsService, useClass: MockGlobalsService },
{ provide: OrgService, useClass: MockOrgService },
{ provide: ActivatedRoute, useValue: routeStub }
],
declarations: [ OrgDetailComponent ],
})
.compileComponents();
}));
My component function being tested:
private gotoParent(): void {
this.router.navigate(['../'], { relativeTo: this.route });
}
public save(): void {
this.error = null;
let that = this;
this.orgService
.save(that.org)
.subscribe(
(org: Org): void => {
that.org = org;
that.savedOrg = new Org(org);
that.gotoParent();
},
error => this.error = error
);
}
My test:
it('responds to the Save click by saving the Org and refilling the component', async(() => {
fixture.detectChanges();
fixture.whenStable().then(() => {
comp.org.id = 2;
comp.org.name = 'Another Org';
let elButton = fixture.debugElement.query(By.css('#save'));
elButton.nativeElement.click();
fixture.detectChanges();
fixture.whenStable().then(() => {
expect(comp.error).toBeNull();
expect(comp.savedOrg.id).toEqual(2);
expect(comp.savedOrg.name).toEqual('Another Org');
expect(routeStub).toHaveBeenCalledWith(['../']);
});
});
When I use breakpoints I see that the OrgService.save() is called when click() is run, and that in the component save() function the that.savedOrg is being set. But when the test gets into the expect() functions comp.savedOrg is at its original value. It is as though there are two component instances.
FWIW, after setting, or not setting, my savedOrg my function then tries to route. I instead get an error:
Error: Expected a spy, but got Object({ data: ScalarObservable({ _isScalar: true, value: Object({ org: Org({ id: 2, [SNIP]
I'm not sure what I'm supposed to do to tell that the "goToParent" routing has been called.
Thanks in advance for help,
Jerome.
I figured out the "not seen in test spec function" issue. I am missing a line, right after the first whenStable(), which should be:
comp = fixture.componentInstance;
That makes everything sync OK. Now I must figure out how to make route testing work. That's another job.
Jerome.

Angular2 final version: Injected Service method under unit test returning undefined

I am trying to write some unit-tests on a component that got some services injected into it, to load the data from server. Data is loaded in this component on OnInit() method. I am trying that service method returns some dummy data, using spyOn. Following is unit-test setup -
let comp: MyComponent;
let fixture: ComponentFixture<MyComponent>;
let staticDataService: any;
let spy: jasmine.Spy;
let allCountries: string[];
describe('MyComponent', () => {
beforeEach( async(() => {
TestBed.configureTestingModule({
imports : [ FormsModule, HttpModule ],
declarations : [MyComponent],
providers: [ StaticDataService ]
})
.compileComponents();
}));
beforeEach(() => {
fixture = TestBed.createComponent(MyComponent);
comp = fixture.componentInstance;
staticDataService = fixture.debugElement.injector.get(StaticDataService);
allCountries = [] = ["US", "UK"];
spy = spyOn(staticDataService, 'getCountries').and.returnValue(Promise.resolve(allCountries));
});
it('Countries should be set', () => {
expect(comp.allCountries).toEqual(allCountries);
});
});
Following is the component class that I am unit-testing -
#Component({
moduleId: module.id,
selector: 'myeditor',
templateUrl: 'my.component.html',
styleUrls: ['my.component.css']
})
export class MyComponent implements OnInit {
allCountries: string[];
constructor(private _staticDataServices: StaticDataService) {}
ngOnInit() {
this.getDataFromServer();
}
getDataFromServer()
{
this.allCountries = this._staticDataServices.getCountries();
}
I am getting the following error -
Chrome 53.0.2785 (Windows 7 0.0.0) MyComponent Countries should be set FAILED
[1] Expected undefined to equal [ 'US', 'UK' ].
Under the same unit-tests few other tests are working fine, that are not dependent on injected services. Getting 'undefined' while testing the properties that are set by services.
Can someone please help what I am doing wrong here?
Thanks
You need to call fixture.detectChanges() for the ngOnInit to be called.
fixture = TestBed.createComponent(MyComponent);
fixture.detectChanges();
getCountries returns a Promise so you need to then it, otherwise the value of allCountries will just be promise and not the data
getDataFromServer() {
this._staticDataServices.getCountries().then(data => {
this.countries = data;
});
}
Since the promise is asynchronous, you need to use async and wait for the asynchronous task to complete by calling fixture.whenStable()
import { async } from '#angular/core/testing';
it('...', async(() => {
fixture.whenStable().then(() => {
expect(comp.allCountries).toEqual(allCountries);
})
})
UDPATE
Without seeing the StaticDataService, I'm guessing you are trying to inject Http into it. This wont work in a test environment without further configuration. What I suggest you do is just make the service a mock
staticDataService = {
getCountries: jasmine.createSpy('getCountries').and.returnValue(...);
}
providers: [
{ provide: StaticDataService, useValue: staticDataService }
]