Typhoon initialization fails when using a protocol as an assembly interface

Question

I'm trying to convert a large application to use protocols instead of classes as assemblies. It's all fairly straightforward, but it's failing to initialize correctly. I've traced through the problem. When Typhoon initializes the assemblies, it interrogates the properties on each assembly and if they are Typhoon classes, initializes them. When I convert a property typed to a Typhoon class it works great; when I convert the property to a protocol type Typhoon does not recognize it as a Typhoon class and doesn't initialize it and initialization fails.

All of the relevant Typhoon code is in the method resolveCollaboratingAssemblies within [TyphoonAssembly init].

Here's example code:

This works:

@class myCoreAssembly : TyphoonAssembly

@interface

@property (readonly, weak, nonatomic) myCoreAssembly *coreAssembly;

(methods)

@end 

This does not:

@protocol myCoreAssemblyProtocol

@interface

@property (readonly, weak, nonatomic) id <myCoreAssemblyProtocol> coreAssembly;

(methods)

@end 

@class myCoreAssembly :TyphoonAssembly <myCoreAssemblyProtocol>

@interface

@property (readonly, weak, nonatomic) id <myCoreAssemblyProtocol> coreAssembly;

(methods)

@end 

At one point during the Typhoon Init process (method propertyForName:(NSString *)propertyName isCollaboratingAssemblyPropertyOnClass:(Class)class) the code checks to see if the property type is a subclass of TypeAssembly. The protocol version does not pass this test.

Any thoughts on a workaround?

Answer 1

I think I've found a solution. I typed the properties as TyphoonAssembly and the auto-injection works again.

Didn't work:

@property (readonly, weak, nonatomic) id <myCoreAssemblyProtocol> coreAssembly;

Works:

@property (readonly, weak, nonatomic) TyphoonAssembly <myCoreAssemblyProtocol> *coreAssembly;

That makes sense, too, as to be auto-injected the property needs to be a subclass of TyphoonAssembly.