github/ReactiveCocoa — pull request #147 by jspahrsummers (2012-11-28 04:39:22+00:00)
Title: Fix RACSubscriber, RACReplaySubject thread safety; remove RACAsyncSubject

#138, #87

As part of fixing up `RACSubscriber`, it now _actually_ terminates any subscription upon `-sendCompleted` or `-sendError:`, to prevent race conditions that might cause next/completed/error to be sent after a previous completed/error.

`RACSubscriber` was documented to do this before, but it was never implemented. Some `` methods depended on this behavior (contradicting the documentation), and those have been refactored accordingly.