Bug? Perhaps improper behavior of throttle(fn)

[benlesh]

RxJS version: 5.0.0-alpha.* to 5.2.0

Code to reproduce:

Observable.of(1, 2, 3).throttle(() => { throw new Error('oops'); })
  .subscribe(x => console.log(x), err => console.log(err.message));

Expected behavior:

logs:

1
"oops"

Actual behavior:

logs

"oops"

Additional information:

Apparently, the durationSelector function is called, and it's result is subscribed to before the leading value is emitted. This seems unintuitive, as it's that value that triggered the need to get the duration notifier from the durationSelector to begin with.

If we "fix" this, it is, indeed, a breaking change.

[benlesh]

Closing as stale