@angular/common/http/testing TestRequest.flush a boolean value

Question

I want to test use of an endpoint that will return true or false as the response. Not 'true' but a boolean value of true. I am using the @angular/common/http/testing module. For other response values I can use TestResponse.flush(value), but this does not work for a boolean value. Instead, the testing module complains

Automatic conversion to JSON is not supported for response type.

---

Here is my test code:

const FLUSH_OK = {status: 200, statusText: 'Ok'};

//.. describe...
it('should work', async(() => {
  service.myFunction().subscribe((data) => { // my Function returns Observable<boolean>, the real endpoint returns a true/false boolean
    expect(data).toEqual(true);
  });

  // this fails: Failed: Automatic conversion to JSON is not supported for response type.
  httpMock.expectOne((req) => {
    return req.url === MY_URL;
  }).flush(true, FLUSH_OK);

 // this also fails: Expected 'true' to equal true.
 // httpMock.expectOne((req) => {
 //   return req.url === MY_URL;
 // }).flush('true', FLUSH_OK);

}));

Answer 1

Using the event method rather than flush allows you to specify the type of the response body.

const req = httpMock.expectOne('some-url');
req.event(new HttpResponse<boolean>({body: true}));

You could optionally also set other properties such as status or statusText.

HttpResponse docs

Original answer