Swift Inheritance Issue - Cannot access inherited properties - objective-c

Question

I'm running into a strange issue that involves simple inheritance in Swift. I might be doing something totally stupid so if anyone has any advice.. thanks in advance!
I am using the latest XCode 6 GM version 6A313.
Here are the 2 Swift classes that's made Objective-C backward compatible.
#objc
public class ObjectA : NSObject {
var testProp: String!
init(testProp: String) {
self.testProp = testProp
}
}
#objc
public class ObjectB : ObjectA {
var testPropB: String!
init(testProp: String, testPropB: String) {
self.testPropB = testPropB
super.init(testProp: testProp)
}
}
I then initialize and use the object in Objective-C code.
ObjectB *objectB = [[ObjectB alloc] initWithTestProp: #"TestProp" testPropB: #"TestPropB"];
// This executes correctly and has the correct value
NSLog(#"%#", objectB.testPropB);
// I then pass this newly constructed object to another class that's written in Swift
AnotherClass *anotherClass = [[AnotherClass alloc] init];
[anotherClass someMethod:objectB];
Here is the Swift class where when I attempt to access the inherited property, I get an EXC_BAD_ACCESS code 1.
#objc
public class AnotherClass : NSObject {
public func someMethod(objectB: ObjectB) {
// This executes and assigns correctly
let prop = objectB.testProp
// This errors out with EXC_BAD_ACCESS error code 1
// In the debugger, objectB.testPropB actually seem to have the correct value
let propB = objectB.testPropB
}
}

Answer 1

var testProp: String!
There is no reason for this to be an implicitly unwrapped optional. You always initialize it in init. If possible, it should be:
let testProp: String
If it must be mutable after assignment, then it should be:
var testProp: String
Fixing this will probably cause the compiler to shout at you where you're doing something wrong (possibly not in the code you've posted here). With a !, it is legal to fail to initialize this value (you'll just crash later). Without a !, the compiler will better verify that you do initialize this value.
This line:
ObjectB *objectB = [[ObjectB alloc] initWithTestProp: #"TestProp", testPropB: #"TestPropB"];
is not correct ObjC (there's an extra comma). I'll assume that it's a typo. I don't think that can result in a legal C comma-operator that would cause the wrong initializer to run. But maybe... it's at least worth checking if you actually do have a comma in there. (I'm pretty sure testPropB:#"..." isn't a legal expression, so this is a little far-fetched, but it would match your symptom).

Answer 2

So, I ended up creating a dummy project to test my theory in a more controlled environment. The fix is basically to ensure that ObjectA and ObjectB are in 2 separate Swift files. When they are in the same Swift file, the error occurs.
Here is the sample code for anyone interested.
https://github.com/MystKnight/swift-inheritance-test
I'm not sure why this is but for everyone out there, I guess limit your files to one class if you are using inheritance...