Fix retryWhen/repeatWhen potential concurrent reentry when resubscribing #4241
+2
−2
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When the function's returned Observable signals the resubscription in the operator
redo
(which is the base forrepeatWhen
andretryWhen
). It is possible an asyncronous source triggers the function (and thus the sameObservable
) from another thread while the first is still coming back from the resubscription itself.This PR serializes the dispatching
BehaviorSubject
to prevent such concurrent execution of the when chain.This may or may not be the source of the failure of #4175 but I can't reproduce the failure with the 1.x branch. /cc @davidmoten.