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

• iOS
• macOS
• tvOS
• watchOS
• playgrounds

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

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

Xcode version:

  Xcode version goes here

⚠️ 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. ⚠️

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)
• no

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

• 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.