Uncaught error is not being thrown in certain situation

[olessavluk]

RxJS version:
versions after 5.1.0 (including)

Code to reproduce:

Rx.Observable.of(null)
  .delay(1)
  .flatMap(v => (new Rx.BehaviorSubject(null)).map(() => v))
  .map(() => {
    throw new Error('tasty error');
  })
  .startWith('error should go next')
  .subscribe(
    v => console.log(v)
  );

you can also run this code in JSBin

Expected behavior:
Uncaught Error: tasty error should be thrown

Actual behavior:
Error was swallowed

Additional information:

• This was introduced in v.5.1.0 (previous works fine for me)
• If you try to remove delay or flatMap + BehaviourSubject error is thrown

[kwonoj]

this is dupe of #2565, there seems some odds around subject.

[lock]

This thread has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.