Observable.takeUntil wrong documentation

[Maragues]

According to Observable.takeUntil(ObservableSource other)'s documentation

Returns an Observable that emits the items emitted by the current Observable until a second ObservableSource emits an item.

Emphasis is mine

Looking at ObservableTakeUntil, it looks to me that onNext and onComplete are equivalent

I created this test, and the output is exactly the same

class TakeUntilTest {
    @Test
    fun `when Observable completes, then takeUntil completes`(){
        Observable.just(1, 2, 3)
            .takeUntil(Observable.empty<Unit>())
            .subscribe(
                {
                    println("Item: $it")
                },
                Timber::e,
                {
                    println("onComplete")
                }
            )
    }
    
    @Test
    fun `when Observable emits, then takeUntil completes`(){
        Observable.just(1, 2, 3)
            .takeUntil(Observable.just(Unit))
            .subscribe(
                {
                    println("Item: $it")
                },
                Timber::e,
                {
                    println("onComplete")
                }
            )
    }
}

According to documentation, the first test should emit 1, 2 and 3 values

Thus, I think the documentation should say something like

Returns an Observable that emits the items emitted by the current Observable until a second ObservableSource emits an item or completes successfully.

Thanks!

[akarnokd]

Yes. PR welcome.

[Maragues]

What do you use to generate marble diagrams? This https://rx-marbles-online.herokuapp.com/ ?

It'd help to add whichever tool you use to contributing documentation https://github.com/ReactiveX/RxJava/blob/3.x/CONTRIBUTING.md, as well as wording guidelines for documentation

[akarnokd]

Don't worry about the diagram, I have an Excel spreadsheet for them.

[akarnokd]

You can use these:

Resize: 640 x 188
URL: https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/Flowable.takeUntil.p.png

Resize: 640 x 213
URL: https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/Observable.takeUntil.o.png