"Value is never used as Publisher" - what does this mean?

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Permanently deleted user
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I've started seeing warnings "Value is never used as Publisher ", for example from this code:

override val locationObserver: Observable<Location> = Observable.create {
    emitter = it
}

I have no idea what this means. The value certainly does get used elsewhere. Now I could just disable the inspection but I would like to know what it means before doing that.

 

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Konstantin Annikov
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May you share entire code sample? 

Inspection description could be found under Settings (Preferences on macOS) | Editor | Inspections | Reactive Streams | Common | Unused publisher: https://i.imgur.com/Nw0Kubn.png

at the same place, you can disable it. 

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Permanently deleted user
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Here is a complete sample. So from the description this is actually a bug (false positive) - the Provider *is* subscribed to.

@Test
fun demo() {
    lateinit var emitter: ObservableEmitter<Int>
    val provider = object  {
        val locationObserver: Observable<Int> = Observable.create {
            emitter = it
        }
    }

    provider.locationObserver.subscribe {
        println(it)
    }

    emitter.onNext(1)
    emitter.onComplete()
}
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Konstantin Annikov
Created

Will be fixed in IntelliJ IDEA 2020.3. We are working on backporting to 2020.2: https://youtrack.jetbrains.com/issue/IDEA-245639

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