#available is unable to detect API availability between WatchOS 2 and iOS

Originator:me
Number:rdar://22529125 Date Originated:01/09/2015
Status:Open Resolved:
Product:Swift Product Version:Xcode Version 7.0 beta 6 (7A192o)
Classification:Important Reproducible:
 
Summary:
Consider the following scenario of code shared between iOS and WatchOS:

lazy var session: WCSession = {
    let session = WCSession.defaultSession()
    session.delegate = self
    return session
}()

...

if #available(iOS 9.0, *) {
    guard session.paired else { throw WatchBridgeError.NotPaired } // Error: paired is not available
    guard session.watchAppInstalled else { throw WatchBridgeError.NoWatchApp } // Error: watchAppInstalled is not available
}

guard session.reachable else { throw WatchBridgeError.NoConnection }

Steps to Reproduce:
Try to use #available in code shared by a WatchOS 2 and iOS target with API that is annotated with __WATCHOS_UNAVAILABLE on WatchOS 2 and iOS.

Expected Results:
No Compiler errors

Actual Results:
Compiler complains with unavailable API usage even though code if wrapped in appropriate #available

Version:
Xcode Version 7.0 beta 6 (7A192o)

Comments


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