Unit Test HttpClient - Angular/Karma

Question

I am going through some articles on unit testing and have found some pretty helpful examples. Most examples I am running across seem to be unit testing a function that does something with the Angular HttpClient and most look like this:

it('should return an Observable<User[]>', () => {
    const dummyUsers = [
      { login: 'John' },
      { login: 'Doe' }
    ];

    service.getUsers().subscribe(users => {
      expect(users.length).toBe(2);
      expect(users).toEqual(dummyUsers);
    });

    const req = httpMock.expectOne(`${service.API_URL}/users`);
    expect(req.request.method).toBe("GET");
    req.flush(dummyUsers);
  });

https://medium.com/netscape/testing-with-the-angular-httpclient-api-648203820712

This means that .getUsers() returns an observable. However, in my application, I am not returning an observable. Almost all of my HttpClient calls are similar to this:

async getCurrentUser(): Promise<UserInfo> {
     return await this._httpClient.get(`/api/me`).toPromise();
}

How do you go about unit testing the function calling the HttpPost or HttpGet within Karma?

Attempt:

  it('should get current user', async () => {
    const result = service.getCurrentUser();
    console.log('RESULT', result);
    const req = httpMock.expectOne(`/api/me`);
    const test = req.flush({test: 'ing'});
    console.log('REQUEST', test);

    expect('a').toEqual('a');
  });

Answer 1

I think I was overthinking it, but I managed to get it working by using .then rather than using await like I would in a normal (non-test) call:

it('should get current user', async () => {
    const response = new CustomResponseClass();
    response.success = true;
    response.error = null;
    const user = new User();
    user.userId = 1;
    user.name = 'Test User';
    response.data = user;
    service.getCurrentUser().then( _user => {
      console.log('USER', _user);
      // TODO: Some more unit tests here...
    });
    const req = httpMock.expectOne('/api/me');
    expect(req.request.method).toEqual('GET');
    req.flush(response);
  });