Mock components, services, and more to simplify Angular testing

ng-mocks simplifies Angular testing and helps you:

• mock Components, Directives, Pipes, Modules, Services and Tokens
• reduce boilerplate in tests
• access declarations through a simple interface

The current version of the library has been tested and can be used with:

angular	ng-mocks	jasmine	jest	vitest	ivy	standalone	signals	defer
22	latest	yes	yes	yes	yes	yes	yes	yes
21	latest	yes	yes	yes	yes	yes	yes	yes
20	latest	yes	yes	yes	yes	yes	yes	yes
19	latest	yes	yes		yes	yes	yes	yes
18	latest	yes	yes		yes	yes	yes	yes
17	latest	yes	yes		yes	yes	yes	yes
16	latest	yes	yes		yes	yes	yes
15	latest	yes	yes		yes	yes
14	latest	yes	yes		yes	yes
13	latest	yes	yes		yes
12	latest	yes	yes		yes
11	latest	yes	yes		yes
10	latest	yes	yes		yes
9	latest	yes	yes		yes
8	latest	yes	yes
7	latest	yes	yes
6	latest	yes	yes
5	latest	yes	yes

Angular 20's native Vitest support is zoneless-only because its supported Zone.js version has no Vitest patch.

Important links

• Documentation with examples of Angular testing
• CHANGELOG
• GitHub repo
• NPM package

• Live example on CodeSandbox
• Live example on StackBlitz

• start a discussion on GitHub
• ask a question on Stackoverflow
• report an issue on GitHub
• chat on gitter

Very short introduction

Put the global configuration for mocks in the setup file for your test runner. For Jasmine, use src/test.ts. For Jest, use src/setup-jest.ts / src/test-setup.ts. For Vitest, use src/setup-vitest.ts and follow the native Angular setup.

// All methods in mock declarations and providers
// will be automatically spied on their creation.
// https://ng-mocks.sudo.eu/extra/auto-spy
ngMocks.autoSpy('jasmine');
// In setup-jest.ts: ngMocks.autoSpy('jest');
// In setup-vitest.ts: ngMocks.autoSpy('vitest');

// ngMocks.defaultMock helps to customize mocks
// globally. Therefore, we can avoid copy-pasting
// among tests.
// https://ng-mocks.sudo.eu/api/ngMocks/defaultMock
ngMocks.defaultMock(AuthService, () => ({
  isLoggedIn$: EMPTY,
  currentUser$: EMPTY,
}));

An example of a spec for a profile edit component.

// Let's imagine that there is a ProfileComponent
// and it has 3 text fields: email, firstName,
// lastName, and a user can edit them.
// In the following test suite, we would like to
// cover the behavior of the component.
describe('profile:builder', () => {
  // Helps to reset customizations after each test.
  // Alternatively, you can enable
  // automatic resetting in test.ts.
  MockInstance.scope();

  // Let's configure TestBed via MockBuilder.
  // The code below says to mock everything in
  // ProfileModule except ProfileComponent and
  // ReactiveFormsModule.
  beforeEach(() => {
    // The result of MockBuilder should be returned.
    // https://ng-mocks.sudo.eu/api/MockBuilder
    return MockBuilder(
      ProfileComponent,
      ProfileModule,
    ).keep(ReactiveFormsModule);
    // // or the old-fashioned way
    // return TestBed.configureTestingModule({
    //   imports: [
    //     MockModule(SharedModule), // mock
    //     ReactiveFormsModule, // real
    //   ],
    //   declarations: [
    //     ProfileComponent, // real
    //     MockPipe(CurrencyPipe), // mock
    //     MockDirective(HoverDirective), // mock
    //   ],
    //   providers: [
    //     MockProvider(AuthService), // mock
    //   ],
    // }).compileComponents();
  });

  // A test to ensure that ProfileComponent
  // can be created.
  it('should be created', () => {
    // MockRender is an advanced version of
    // TestBed.createComponent.
    // It respects all lifecycle hooks,
    // onPush change detection, and creates a
    // wrapper component with a template like
    // <app-root ...allInputs></profile>
    // and renders it.
    // It also respects all lifecycle hooks.
    // https://ng-mocks.sudo.eu/api/MockRender
    const fixture = MockRender(ProfileComponent);

    expect(
      fixture.point.componentInstance,
    ).toEqual(jasmine.any(ProfileComponent));
  });

  // A test to ensure that the component listens
  // on ctrl+s hotkey.
  it('saves on ctrl+s hot key', () => {
    // A fake profile.
    const profile = {
      email: 'test2@email.com',
      firstName: 'testFirst2',
      lastName: 'testLast2',
    };

    // A spy to track save calls.
    // MockInstance helps configure mock
    // providers, declarations and modules
    // before their initialization and usage.
    // https://ng-mocks.sudo.eu/api/MockInstance
    const spySave = MockInstance(
      StorageService,
      'save',
      jasmine.createSpy(), // or jest.fn()
    );

    // Renders <profile [profile]="params.profile">
    // </profile>.
    // https://ng-mocks.sudo.eu/api/MockRender
    const { point } = MockRender(
      ProfileComponent,
      { profile }, // bindings
    );

    // Let's change the value of the form control
    // for email addresses with a random value.
    // ngMocks.change finds a related control
    // value accessor and updates it properly.
    // https://ng-mocks.sudo.eu/api/ngMocks/change
    ngMocks.change(
      '[name=email]', // css selector
      'test3@em.ail', // an email address
    );

    // Let's ensure that nothing has been called.
    expect(spySave).not.toHaveBeenCalled();

    // Let's assume that there is a host listener
    // for a keyboard combination of ctrl+s,
    // and we want to trigger it.
    // ngMocks.trigger helps to emit events via
    // simple interface.
    // https://ng-mocks.sudo.eu/api/ngMocks/trigger
    ngMocks.trigger(point, 'keyup.control.s');

    // The spy should be called with the profile
    // and the random email address.
    expect(spySave).toHaveBeenCalledWith({
      email: 'test3@em.ail',
      firstName: profile.firstName,
      lastName: profile.lastName,
    });
  });
});

Profit.

Extra

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Thank you!

P.S. Feel free to contact us if you need help.