NestJS Auto Mockito

This is a specific implementation of nestjs-auto-mock, using ts-mockito as the chosen mocking/spying module. Adds an easy way to automatically add mocks of dependencies from the service/controller being tested.

It adds auto mocking of given providers, being it directly or a given module(s) providers.

The mocked service used depends on the actual implementation.

Base documentation

For more documentation check the abstract module https://github.com/MigasEu/nestjs-auto-mock

Features

Automatically mocking providers

Automatically reads module like metadata and finds what providers can be mocked. It will create a mock and an instance for each one of those, using ts-mockito.

Instance is provided to nest's testing module like any other provider and the mock is stored, allowing the user to get it easily, with the .getMock() function.

Exceptions

Most providers will be automatically mocked, unless we can't find a corresponding Class for that provider. When a provider is configured as a factory and a string identifier (provide), we do not know what to mock, so it is ignored.

Example: { provide: 'providerIdentifier', useFactory: () => { return {a: 1}; }}

You can create and add add-ons to avoid this issue.

Mocking providers of a given module

It can reads the metadata for existing modules recursively to create mocks for all the providers withing that module, including nested ones.

Usage Example

  beforeEach(async () => {
    const app = await MockitoTest.createMockitoModule(
      // Real metadata (will start a real service instance)
      {
        providers: [SomeService],
      },
      // Metadata to mock (Providers under SomeModule will also be mocked)
      {
        providers: [
          // Mocking directly a given provider
          {
            provide: getLoggerToken(SomeService.name),
            useClass: PinoLogger,
          },
          MailerService,
        ],
        // Mocking all providers found (deep) inside a given Module
        imports: [SomeModule],
      },
    ).compileMocked();

    service = app.get<SomeService>(SomeService);
    repositoryMock = app.getMock<Repository<SomeEntity>>(
      getRepositoryToken(SomeEntity),
    );
    configMock = app.getMock(ConfigService);
    mailerService = app.getMock(MailerService);
  });

  // (...)

  it('should have only main price', async () => {
    // (...)

    when(repositoryMock.create(anything() as SomeEntity)).thenReturn(SomeEntity);
    when(repositoryMock.save(anything())).thenResolve(SomeEntity);

    const result = await service.create(createDto);

    expect(result).toEqual({ newSomeEntity: SomeEntity, session: stripeSession });
    verify(repositoryMock.create(deepEqual(createDto))).once();
    verify(
    repositoryMock.save(
        deepEqual(
        Object.assign(new SomeEntity(), {
            ...SomeEntity,
            active: false,
        }),
        ),
    ),
    ).once();
  });