mostRecent returning NotificationLite#ON_NEXT_NULL_SENTINEL

[yogurtearl]

This can return NotificationLite#ON_NEXT_NULL_SENTINEL or NotificationLite#ON_COMPLETED_SENTINEL.

Observable<Foo> observable = .... ;
Foo foo = observable.toBlocking().mostRecent(null).iterator().next()

which will cause a ClassCastException....

This seems inconsistent with the docs and it didn't used to do this ( in 0.17.5 )
https://github.com/Netflix/RxJava/wiki/Blocking-Observable-Operators#mostrecent

Looks like the fix will probably relate to BlockingOperatorMostRecent.MostRecentObserver

[benjchristensen]

Thanks for reporting this. I think I know what caused this.

[benjchristensen]

@abersnaze Do you have time to take a look at this?

[abersnaze]

Sure, I'll take look.

[benjchristensen]

Fixed in #1552