I m trying to write test case for subscribe method.
code to check
When I test with
ng test --code-coverage true
Test case is passing, but in code coverage report subscribe method is not covered
npm run sonar-scanner
Could anyone help with this?
Create a mock service and inject it as providers in component.spec.ts:
import { of } from 'rxjs';
export class MockService{
validate(){
return of()
}
queryUser(){
return of({username: 'myUser'})
}
}
and then inject as
providers : [
{provide: YourActualService , useClass: MockService}
]
and then test it as :
it('should initilize user name',()=> {
component.token = "123";
fixture.detectChanges();
expect(component.uname).toBe('myUser')
})
The useClass would replace your service of component with our MockService in which we are returning an observable using of()
Related
I am not sure how to implement unit test in nestjs and typeorm without connecting to db. I have tried a number of technic but non seem to work.
My module looks something like this.
import { HttpModule, Module } from '#nestjs/common'
import moment from 'moment';
import config from '#app/config'
import { OrdersService } from './services/order.service'
import { FraudOrderChecksService } from './services/fraud-order-checks.service'
import { FraudOrderChecksController } from './controllers/fraud-order-checks.controller'
import { HealthcheckController } from './controllers/healthcheck.controller';
import { TypeOrmModule } from '#nestjs/typeorm'
import { ormconfig } from './entities/ormconfig'
#Module({
imports: [
SharedModule,
HttpModule,
LoggerModule,
ConfigModule.forRoot(config),
TypeOrmModule.forRoot(ormconfig.luminskin as any),
TypeOrmModule.forRoot(ormconfig.meridian as any),
TypeOrmModule.forFeature([...ormconfig.luminskin.entities], 'luminskin'),
TypeOrmModule.forFeature([...ormconfig.meridian.entities], 'meridian'),
...
],
controllers: [
MyController,
...
],
providers: [
...
],
})
export class AppModule { }
I import the root module in my test
beforeEach(async () => {
jest.clearAllMocks();
const module: TestingModule = await Test.createTestingModule({
imports: [InternalModule]
}).compile();
...
});
When I try to run my unit test I get
[Nest] 93196 - 06/04/2021, 17:43:50 [ExceptionHandler] Unable to connect to the database (mydb). Retrying (1)...
AlreadyHasActiveConnectionError: Cannot create a new connection named "connectionname", because connection with such name already exist and it now has an active connection session.
How do I decouple the connection from the root module, so it is only ran when needed. Actually cleaner technic will also be accepted.
You don't want to unit test a module, you want to unit test a modules individual components in isolation.
Although you can create a TestModule and simply import your module as you have done above, I would only consider doing that when the module contained a single component (even then I wouldn't as I don't think its very good practice).
The more components you bring into your test:
The more moving parts you need to manage
The more you have to mock
The less portability you have with the unit and its test
The more aspirin you ingest trying resolve self induced headaches that occur every time you modify its parent module
Nests TestingModule enables you to "rig" up an independent module with the bare minimum needed to test your component in isolation. It simplifies your test setups and mock creation/management.
Always try to look at unit testing as a stand alone, independent processes. Limit the scope and dependencies wherever possible to make testing as effective and easy as possible.
Here is an example of the approach I take for unit testing a service where I mock out its dependencies:
// app.service.spec.ts
describe('Testing app.service', () => {
let module: TestingModule;
let service: AppService;
// mock out providers the service depends on
const mockProviders = [
{
provide: ConfigService,
useValue: {
get: jest.fn().mockReturnValue('Mock!'),
},
},
];
beforeAll(async () => {
// build up testing module
module = await Test.createTestingModule({
imports: [],
providers: [...mockProviders, AppService],
})
.compile()
.catch((err) => {
// Helps catch ninja like errors from compilation
console.error(err);
throw err;
});
service = module.get<AppService>(AppService);
});
it('Should return: Hello Mock!', async () => {
const response = service.getHello();
expect(response).toEqual('Hello Mock');
});
});
I try to keep all business logic (wherever possible) in services, leavingcontrollers light and generally reserved for e2e and/or integration testing.
This isn't the only (and maybe not even "the best") approach, but it helps me to keep my tests and services more focused.
I am work on the angular testing for first time and from monring i struggling to test this. I added both modules inside TestBed and injected but real method is always called instead of returning value from getMockFeatureState(). Please help fix this. Thannks
beforeEach(() => {
TestBed.configureTestingModule({
imports: [ HttpClientModule ],
providers: [ FeatureToggleService, ConfigService]
});
});
it('should return values based on mock feature state', () => {
const featureService = TestBed.inject(FeatureToggleService);
const configService = TestBed.inject(ConfigService);
const mockFeaturesSpy = spyOn(configService, 'getMockFeatures')
.and.returnValue(getMockFeatureState());
expect(featureService.isFeatureEnabled('feature1')).toBeFalsy();
expect(featureService.isFeatureEnabled('feature2')).toBeFalsy();
});
I recently faced the same issue in one of my tests. The order of TestBed.inject was the issue. If FeatureToggleService requires ConfigService. You have to inject ConfigService first and mock it before injecting the featureService. You can try
it('should return values based on mock feature state', () => {
const configService = TestBed.inject(ConfigService);
const mockFeaturesSpy = spyOn(configService, 'getMockFeatures')
.and.returnValue(getMockFeatureState());
const featureService = TestBed.inject(FeatureToggleService);
expect(featureService.isFeatureEnabled('feature1')).toBeFalsy();
expect(featureService.isFeatureEnabled('feature2')).toBeFalsy();
});
I also moved the injection of dependency service into beforeEach block like mentioned in other answer so that it can be applied for other tests too
I'm playing with mount() from vue-test-utils, have a component that imports services that should be mocked in the unit test.
I see that mount() has a mocks option, but trying to extrapolate the example given at guides, common-tips, mocking injections to the scenario of an injected service is eluding me.
mount(Component, {
mocks: {
...?
}
})
The component simply imports the service, which is plain JS
import DataService from '../services/data.service'
I can get it working using the inject-loader which is detailed here Testing With Mocks
The code that does work
const MyComponentInjector = require('!!vue-loader?inject!./MyComponent.vue')
const mockedServices = {
'../services/data.service': {
checkAll: () => { return Promise.resolve() }
},
}
const MyComponentWithMocks = MyComponentInjector(mockedServices)
const wrapper = mount(MyComponentWithMocks, { store: mockStore, router })
What is the syntax for mount(MyComponent, { mocks: ... })?
Since mount() has a mocks option, should it not be possible to pass mockedServices to it in some form?
mocks refers to the Vue instance. You're trying to mock a file dependency, which is a different problem. As you said, one solution is inject-loader. Another is the babel-plugin-rewire.
Let me clear up what the mocks option does.
mocks adds properties to the Vue instance.
If you have an app that injects $route, you might have a component that tries to access it: this.$route.path:
...
methods: {
logPath() {
console.log(this.$route.path)
}
}
...
If you try to mount this component without installing Vue router, it will throw an error. To solve this, you can use the mocks mount option to inject a mock $route object to the Vue instance:
const $route = { path: 'some/mock/value' }
mount(Component, {
mocks: {
$route
}
})
I have just started with Unit-Testing, and I have been able to mock my own services and some of Angular and Ionic as well, but no matter what I do ChangeDetectorRef stays the same.
I mean which kind of sorcery is this?
beforeEach(async(() =>
TestBed.configureTestingModule({
declarations: [MyComponent],
providers: [
Form, DomController, ToastController, AlertController,
PopoverController,
{provide: Platform, useClass: PlatformMock},
{
provide: NavParams,
useValue: new NavParams({data: new PageData().Data})
},
{provide: ChangeDetectorRef, useClass: ChangeDetectorRefMock}
],
imports: [
FormsModule,
ReactiveFormsModule,
IonicModule
],
})
.overrideComponent(MyComponent, {
set: {
providers: [
{provide: ChangeDetectorRef, useClass: ChangeDetectorRefMock},
],
viewProviders: [
{provide: ChangeDetectorRef, useClass: ChangeDetectorRefMock},
]
}
})
.compileComponents()
.then(() => {
let fixture = TestBed.createComponent(MyComponent);
let cmp = fixture.debugElement.componentInstance;
let cdRef = fixture.debugElement.injector.get(ChangeDetectorRef);
console.log(cdRef); // logs ChangeDetectorRefMock
console.log(cmp.cdRef); // logs ChangeDetectorRef , why ??
})
));
it('fails no matter what', async(() => {
spyOn(cdRef, 'markForCheck');
spyOn(cmp.cdRef, 'markForCheck');
cmp.ngOnInit();
expect(cdRef.markForCheck).toHaveBeenCalled(); // fail, why ??
expect(cmp.cdRef.markForCheck).toHaveBeenCalled(); // success
console.log(cdRef); // logs ChangeDetectorRefMock
console.log(cmp.cdRef); // logs ChangeDetectorRef , why ??
}));
#Component({
...
})
export class MyComponent {
constructor(private cdRef: ChangeDetectorRef){}
ngOnInit() {
// do something
this.cdRef.markForCheck();
}
}
I have tried everything , async, fakeAsync, injector([ChangeDetectorRef], () => {}).
Nothing works.
Update 2020:
I wrote this originally in May 2017, it's a solution that worked great at the time and still works.
We can't configure the injection of a changeDetectorRef mock through the test bed, so this is what I am doing these days:
it('detects changes', () => {
// This is a unique instance here, brand new
const changeDetectorRef = fixture.debugElement.injector.get(ChangeDetectorRef);
// So, I am spying directly on the prototype.
const detectChangesSpy = spyOn(changeDetectorRef.constructor.prototype, 'detectChanges');
component.someMethod(); // Which internally calls the detectChanges.
expect(detectChangesSpy).toHaveBeenCalled();
});
Then you don't care about private attributes or any.
In case anyone runs into this, this is one way that has worked well for me:
As you are injecting the ChangeDetectorRef instance in your constructor:
constructor(private cdRef: ChangeDetectorRef) { }
You have that cdRef as one of the private attributes on the component, which means you can spy on the component, stub that attribute and have it return whatever you want. Also, you can assert its calls and parameters, as needed.
In your spec file, call your TestBed without providing the ChangeDetectorRef as it won't provide what you give it. Set the component that same beforeEach block, so it is reset between specs as it is done in the docs here:
component = fixture.componentInstance;
Then in the tests, spy directly on the attribute
describe('someMethod()', () => {
it('calls detect changes', () => {
const spy = spyOn((component as any).cdRef, 'detectChanges');
component.someMethod();
expect(spy).toHaveBeenCalled();
});
});
With the spy you can use .and.returnValue() and have it return whatever you need.
Notice that (component as any) is used as cdRef is a private attribute. But private doesn't exist in the actual compiled javascript so it is accessible.
It is up to you if you want to access private attributes at runtime that way for your tests.
Not sure if this a new thing or not, but changeDetectorRef can be accessed via fixture.
See docs: https://angular.io/guide/testing#componentfixture-properties
We ran into the same issue with change detector mocking and this is ended up being the solution
Probably one point that needs to be pointed out, is that in essence here you want to test your own code, not unit test the change detector itself (which was tested by the Angular team).
In my opinion this is a good indicator that you should extract the call to the change detector to a local private method (private as it is something you don't want to unit test), e.g.
private detectChanges(): void {
this.cdRef.detectChanges();
}
Then, in your unit test, you will want to verify that your code actually called this function, and thus called the method from the ChangeDetectorRef. For example:
it('should call the change detector',
() => {
const spyCDR = spyOn((cmp as any).cdRef, 'detectChanges' as any);
cmp.ngOnInit();
expect(spyCDR).toHaveBeenCalled();
}
);
I had the exact same situation, and this was suggested to me as a general best practice for unit testing from a senior dev who told me that unit testing is actually forcing you by this pattern to structure your code better. With the proposed restructuring, you make sure your code is flexible to change, e.g. if Angular changes the way they provide us with change detection, then you will only have to adapt the detectChanges method.
For unit testing, if you are mocking ChangeDetectorRef just to satisfy dependency injection for a component to be creation, you can pass in any value.
For my case, I did this:
TestBed.configureTestingModule({
providers: [
FormBuilder,
MyComponent,
{ provide: ChangeDetectorRef, useValue: {} }
]
}).compileComponents()
injector = getTestBed()
myComponent = injector.get(MyComponent)
It will create myComponent successfully. Just make sure test execution path does not need ChangeDetectorRef. If you do, then replace useValue: {} with a proper mock object.
In my case, I just needed to test some form creation stuff using FormBuilder.
// component
constructor(private changeDetectorRef: ChangeDetectorRef) {}
public someHandler() {
this.changeDetectorRef.detectChanges();
}
// spec
const changeDetectorRef = fixture.componentRef.changeDetectorRef;
jest.spyOn(changeDetectorRef, 'detectChanges');
fixture.detectChanges(); // <--- needed!!
component.someHandler();
expect(changeDetectorRef.detectChanges).toHaveBeenCalled();
I'm using yeoman generator created app, and doing my tests in karma.
I have reusable mock objects for every of my service.
How do i correctly replace specific service dependcy with a mock, so i could then use jasmine to spy upon methods
So far i have done like this:
My service:
angular.module('ql')
.service('loginService', ['$http','API','authService', function ($http, API, authService) {
return {
//service implementation
}]);
Mock of authService:
'use strict';
//lets mock http auth service, so it would be spied upon.
ql.mock.$authServiceMockProvider = function() {
this.$get = function() {
var $service = {
loginConfirmed: function() { }
};
return $service;
};
};
//and register it.
angular.module('qlMock').provider({
$authServiceMock: ql.mock.$authServiceMockProvider
});
And my test:
'use strict';
describe('When i call login method()', function () {
// load the service's module
beforeEach(module('ql'));
beforeEach(angular.mock.module('qlMock'));
// instantiate service
var loginService,
authService,
$httpBackend;
beforeEach(function() {
// replace auth service with a mock.
// this seems kind of dirty... is there a bettery way?
module(function($provide, $injector){
authService = $injector.get('$authServiceMockProvider').$get();
$provide.value('authService', authService);
});
//actually get the loginService
/*jshint camelcase: false */
inject(function(_loginService_, _$httpBackend_) {
loginService = _loginService_;
$httpBackend =_$httpBackend_;
});
//http auth module method, that should be call only on success scenarios
spyOn(authService, 'loginConfirmed').andCallThrough();
});
it('it should do something', function () {
//actual test logic
});
});
What i do not like is the line:
authService = $injector.get('$authServiceMockProvider').$get();
I would like to simply somehow get the authServiceMock (without getting provider, and calling et method) and then inject it into loginService.
I know i could call my $authServiceMock simply authService, and provide it as a mock, so that it would always override my default implementation, but i do not want to do this.
I know this is late but maybe it will help someone who happen upon this post.
Mocking a service in Jasmine is quite simple using Angular's $provide service. The trick is to use $provide to swap out a service implementation before injecting the service.
For example let's say we are testing a service that makes use of the $location service to get information about the current URL.
// load the service's module under test
beforeEach(module('myExampleModule'));
// mock out $location with a fake one
beforeEach(module(function ($provide) {
//create mock impl
var mockLocation = {
path: function(){
return '/somewhere'
}
}
$provide.value('$location', mockLocation); // use $provide to swap the real $location with our mock
}));
var $location;
// inject dependencies ($location will be our mocked $location)
beforeEach(inject(function (_$location_) {
$location = _$location_;
}));
it('should return mock url', function(){
var path = $location.path();
expect(path).toBe('/somewhere'); //Assert that $location.path() returns '/somewhere'
});
I think I would simply use an angular service decorator to mock or totally replace your service for tests. Here is an example
I have never unit tested a service in a service, not yet anyways but our authertication/login stuff is coming up soon.
As you are unit testing the loginService you are only interested in the way the service interacts with the data it is given by the AuthService and not that the AuthService is working correctly. Which is what you have set up in the mock.
I think this would be my approach: (inside the parent describe)
var
loginService,
authService
AUTH_DATA
;
beforeEach(function() {
module('ql');
// I am assuming this is the global app module so both services live here? If not include this module as well
});
beforeEach(inject(function (_authService_, _loginService_) {
authService = _authService_;
loginService = _loginService_;
//Now with the spy setup you intercept the calls to the service and you choose what data to return, based on the unit test. Now your LoginService can simply resond to the data it is give from the login service
}));
it('it should do something', function () {
spyOn(authService, 'loginConfirmed').andReturn(AUTH_DATA);
loginService.confirmLogin(); //Dont know your actual API but a contrived guess
expect('something to happen in loginservice when AUTH_DATA is returned').toBe('Something else')
});