recognize when an intermediate class has overridden a method

[samsonjs]

This makes the following code work. Model overrides the method indirectly by subclassing _Model.

I also snuck in a quick fix to SubclassesOfClass so it doesn't return the base class it receives as a param.

@interface Base : NSObject
- (id)someMethod;
@end
@implementation Base
- (id)someMethod { SUBCLASS_MUST_OVERRIDE; return nil; }
@end

@interface _Model : Base @end
@implementation _Model
- (id)someMethod { return @42; }
@end

@interface Model : _Model @end
@implementation Model @end

[samsonjs]

So, this definitely needs more work (or maybe it won't work at all). When a method is implemented in a leaf class instead of an intermediate class then the intermediate class fails the assertion. I'm not really sure how to properly handle that without making a lot of poor assumptions.

[samsonjs]

This is not a good idea. Closing.