ReactiveX/RxSwift

asSingle -> Sequence contains more than one element.

EE-Yat-Ho opened this issue · 5 comments

EE-Yat-Ho commented

Short description of the issue:

asSingle does not forwardOn the value entered as next.
When Subject or Observable is changed to asSingle, it does not work properly.

Expected outcome:

It works normally when you change Subject or Observable to asSingle.

Self contained code example that reproduces the issue:

let ps = PublishSubject()
let disposeBag = DisposeBag()

ps.asSingle()
    .subscribe(onSuccess: { string in
        print("❔ onSuccess \(string)")
    }, onFailure: { error in
        print("❔ onFailure \(error)")
    }, onDisposed: {
        print("❔ onDisposed")
    })
    .disposed(by: disposeBag)

ps.onNext("a")
// not thing print
ps.onNext("b")
// print "❔ onFailure Sequence contains more than one element."
// print "❔ onDisposed"

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:

15.1

⚠️ 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
EE-Yat-Ho commented

I would like to add the code below to .next of AsSingleSink.

self.forwardOn(element)
self.forwardOn(.completed)
danielt1263 commented

That is as designed. In your case, use ps.take(1).asSingle()

EE-Yat-Ho commented

“completed” is issued when “take” receives the specified number of events.
Great.

Efebyts commented

Short description of the issue:

asSingle does not forwardOn the value entered as next.

When Subject or Observable is changed to asSingle, it does not work properly.

Expected outcome:

It works normally when you change Subject or Observable to asSingle.

Self contained code example that reproduces the issue:

let ps = PublishSubject()

let disposeBag = DisposeBag()



ps.asSingle()

    .subscribe(onSuccess: { string in

        print("❔ onSuccess \(string)")

    }, onFailure: { error in

        print("❔ onFailure \(error)")

    }, onDisposed: {

        print("❔ onDisposed")

    })

    .disposed(by: disposeBag)



ps.onNext("a")

// not thing print

ps.onNext("b")

// print "❔ onFailure Sequence contains more than one element."

// print "❔ onDisposed"

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:


15.1

⚠️ 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 commented

@Efebyts I'm not sure why you quoted the original message to this closed topic... Care to elaborate?