Why branches coverage is random?

Question

I have theses 4 unit tests.

const handleHttp = (method: 'POST' | 'GET' | 'PUT' | 'DELETE'): void => {
  const req = httpTestingController.expectOne(`${environment.apiUrl}test`);
  expect(req.request.method).toEqual(method);
  return req.flush({ fake: 1 });
};

it('should make a POST request', fakeAsync(() => {
  service.post('test', { fakeProp: 'fakeValue' }).then((res) => {
    expect(res).toEqual({ fake: 1 });
  });
  handleHttp('POST');
}));

it('should make a GET request', fakeAsync(() => {
  service.get('test').then((res) => {
    expect(res).toEqual({ fake: 1 });
  });
  handleHttp('GET');
}));

it('should make a PUT request', fakeAsync(() => {
  service.put('test', { fakeProp: 'fakeValue' }).then((res) => {
    expect(res).toEqual({ fake: 1 });
  });
  handleHttp('PUT');
}));

it('should make a DELETE request', fakeAsync(() => {
  service.delete('test', { fakeProp: 'fakeValue' }).then((res) => {
    expect(res).toEqual({ fake: 1 });
  });
  handleHttp('DELETE');
}));

Methods options parameters are all same:

post<T>(url: string, body: object, options: object = this.httpOptions): Promise<T> {
get<T>(url: string, options: object = this.httpOptions): Promise<T> {
put<T>(url: string, body: object, options: object = this.httpOptions): Promise<T> {
delete<T>(url: string, options: object = this.httpOptions): Promise<T> {

Result:

75% Branches 3/4

Screenshot:

Only the last param options isn't covered but the first 3 are covered.

Libraries:

"jasmine-core": "~3.4.0",
"jasmine-spec-reporter": "~4.2.1",
"karma": "~4.1.0",
"karma-chrome-launcher": "~2.2.0",
"karma-coverage-istanbul-reporter": "~2.0.1",
"karma-jasmine": "~2.0.1",
"karma-jasmine-html-reporter": "^1.4.0",

So the question: why branche coverage look random or there missed I something in my code ? Should I run the test or doesn't it important ?

Answer 1

The only time you invoke the methods supplying options is in the call to delete (where I suspect you don't actually mean to).