bug(throttle): Does not emit last value on source complete

[benlesh]

throttleTime(n, s, config) should be equivalent to throttle(() => timer(n, s), config)... But it's not. The issue is that throttle does not behave correctly when the source completes.

If the source completes, we're trailing, and we have a trailing value already, the result should wait for the throttle duration to end, then emit the last value, then complete the result. If the source completes and we don't have a trailing value -- or we're not trailing -- the result should complete.

[alexsherekin]

I would like to work on this issue. It looks like a good first task to contribute to RxJS.

[alexsherekin]

After the refactoring the initial bug is fixed. I created a PR with additional tests.

[OliverJAsh]

Until v7 is released, I'm using this workaround:

/**
 * Workaround for https://github.com/ReactiveX/rxjs/issues/5732
 * Fixed in v7
 */
export const throttleWithFix: typeof RxJSOperators.throttle = (...params) => (ob$) =>
  ob$.pipe(
    RxJSOperators.publish((published$) => {
      const last$ = pipe(published$, RxJSOperators.last());
      const throttled$ = pipe(published$, RxJSOperators.throttle(...params));
      return RxJS.merge(throttled$, last$);
    }),
  );

[akaltar]

Is there an option to fix this for a 6.6.7 release?
I'd be happy to try and backport the fix and test from the v7 alpha.

[gewoonwoutje]

Closed?