2.x v2.0.6 Single.merge produce UndeliverableError [Question]

[stepango]

Sorry for code in kotlin.

    @Test fun singleMergeTest() {
        val illegalAccessError = IllegalAccessError()
        Single.merge<String>(listOf(
                Single.error(illegalAccessError),
                Single.error(illegalAccessError),
                Single.error(illegalAccessError)
        )).test().await().assertError(illegalAccessError)
    }

    @Test fun observableMergeTest() {
        val illegalAccessError = IllegalAccessError()
        Observable.merge<String>(listOf(
                Observable.error(illegalAccessError),
                Observable.error(illegalAccessError),
                Observable.error(illegalAccessError)
        )).test().await().assertError(illegalAccessError)
    }

First test produces UndeliverableError after execution but second one completes successfully without errors. Is it expected behaviour or a bug?

[akarnokd]

Thanks for reporting. This is indeed an inconsistency between Observable and the Flowable-based merges not stopping immediately when one of the inner sources fails and subscribing to the next inner source in synchronous mode.

[akarnokd]

Closing via #5133.