TakeUntil Different Working from Docs

[yudonlee]

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Short description of the issue: Says

If this second Observable emits an item or sends a termination notification, the Observable returned by TakeUntil stops mirroring the source Observable and terminates

But if Second Observable terminates, Source observer still can emit the item. description here

Expected outcome:

onNext("A")
onNext("B")

What actually happens:

onNext("A")
onNext("B")
onNext("C")

Self contained code example that reproduces the issue:

let subject = PublishSubject<String>()
let trigger = PublishSubject<String>()

        subject
            .take(until: trigger)
            .subscribe(onNext: {
                print($0)
            })
            .disposed(by: disposBag)

        subject.onNext("A")
        subject.onNext("B")
        trigger.onCompleted()
        subject.onNext("C")

RxSwift/RxCocoa/RxBlocking/RxTest version/commit 6.0.0 version or commit here

Platform/Environment

• [x] iOS
• [ ] macOS
• [ ] tvOS
• [ ] watchOS
• [ ] playgrounds

How easy is to reproduce? (chances of successful reproduce after running the self contained code)

• [x] easy, 100% repro
• [ ] sometimes, 10%-100%
• [ ] hard, 2% - 10%
• [ ] extremely hard, %0 - 2%

Xcode version:

  Xcode version goes here

:warning: Fields below are optional for general issues or in case those questions aren't related to your issue, but filling them out will increase the chances of getting your issue resolved. :warning:

Installation method:

• [ ] CocoaPods
• [ ] Carthage
• [ ] Git submodules

I have multiple versions of Xcode installed: (so we can know if this is a potential cause of your issue)

• [ ] yes (which ones)
• [x] no

Level of RxSwift knowledge: (this is so we can understand your level of knowledge and formulate the response in an appropriate manner)

• [x] just starting
• [ ] I have a small code base
• [ ] I have a significant code base

[danielt1263]

I believe this is a mistake in the documentation. The observable passed into take(until:) will only terminate the source on an onNext or onError event, not for onCompleted.

This is also how the reference implementation for C# works.

[yudonlee]

I believe this is a mistake in the documentation. The observable passed into take(until:) will only terminate the source on an onNext or onError event, not for onCompleted.

This is also how the reference implementation for C# works.

Thank you! I didn't think the document was wrong. But why doesn't the document change?

[danielt1263]

Exactly what file are you talking about with incorrect documentation? I invite you to submit a pull request with the file corrected.

[yudonlee]

The document I'm talking about is the official Reactive.io document.! https://reactivex.io/documentation/operators/takeuntil.html

[danielt1263]

I submitted a PR.