[swift-users] Possible swift 3 method rewrite issue with NSRequestConcreteImplementation ?

[John Spurlock]

Minimal repro case below.  I'm creating a custom NSCoder, but the
"encodeInt:forKey" call is not dispatched properly to my overridden method
when encoding an NSCalendar instance.

What am I missing here?  Without source code for any of this, I'm at a dead
end.

Thanks,
- john

================================================

    private class FooCoder : NSCoder {
        override var allowsKeyedCoding : Bool { return true }

        override func encode(_ objv: AnyObject?, forKey key: String) {
            print("\(key) \(objv)") // called
        }

        override func encode(_ intv: Int, forKey key: String) {
            print("\(key) \(intv)") // never called
        }
    }

    func testCoder() {
        Calendar.current.encode(with: FooCoder())  // crashes at runtime,
result below
    }

Results in:

"NSInvalidArgumentException", "*** -encodeInt:forKey: only defined for
abstract class.  Define -[_TtCC22Tests22TestsP33_1961FooCoder
encodeInt:forKey:]!"
(
0   CoreFoundation                      0x00007fff84da34f2
__exceptionPreprocess + 178
1   libobjc.A.dylib                     0x00007fff883caf7e
objc_exception_throw + 48
2   CoreFoundation                      0x00007fff84e0a4bd +[NSException
raise:format:] + 205
3   Foundation                          0x00007fff903ccdbd
NSRequestConcreteImplementation + 229
4   Foundation                          0x00007fff9035323b
-[NSCalendar(NSCalendar) encodeWithCoder:] + 251
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.swift.org/pipermail/swift-users/attachments/20160718/702fc5d1/attachment.html>