throttleTime(n, undefined, {leading: true, trailing: true}) ... double output

[sod]

RxJS version: 6.5.1
Code to reproduce (6.5.1): https://stackblitz.com/edit/rxjs-tthiju
Expected behavior: One value initially, then defer next value for given duration
Actual behavior: One value initially, two values each duration
Additional information:

Test:

import { interval } from 'rxjs'; 
import { throttleTime, take } from 'rxjs/operators';

interval(50).pipe(
  throttleTime(1234, undefined, {leading: true, trailing: true}),
  take(8),
).subscribe(x => console.log(x));

// actual output: 0----24-25----49-50----74-75----99|
// expected output: 0----24----49----74----99----124----149----174|

[jscti]

Has anybody found a work around on this ?

[tim-kuteev]

Hi jscti,

I think the work around for that might be to to give up on leading value.

.throttleTime(1234, undefined, {leading: false, trailing: true})

Note that in this case you will be missing the first value. And there is also opened issue for single value #2859.

[simeyla]

Would distinctUntilChanged() work after throttleTime - at least for some situations?

[ubugnu]

Would distinctUntilChanged() work after throttleTime - at least for some situations?

Yes it would work, for example:

distinctUntilChanged((prev, curr) => curr - prev < minWaitTime/1000)

[sod]

Well, let me try to propose a fix again via #4864 :D

[adolgoff]

Are there any plans to merge it?