hookshot-customAlloc.mm

+ (id)instrumentInstanceMessagesSwizzledAllocWithZone:(NSZone *)zone {
    id result = [self instrumentInstanceMessagesSwizzledAllocWithZone:zone];
    liveObjectClass[result] = self;
    object_setClass(result, classes[self]);

    return result;
}

+ (id)instrumentInstanceMessagesAddedAllocWithZone:(NSZone *)zone {
    Method method = GetSuperMethod(self, @selector(allocWithZone:));
    IMP imp = method_getImplementation(method);

    id result = imp(self, @selector(allocWithZone:), zone);
    runCallbacks(afterBlocks, result, self, @selector(allocWithZone:));
    liveObjectClass[result] = self;
    object_setClass(result, classes[self]);

    return result;
}

// Later...

if (HasOwnClassMethod(cls, @selector(allocWithZone:))) {
  ClassMethodSwizzle(
      cls, @selector(instrumentInstanceMessagesSwizzledAllocWithZone:),
      @selector(allocWithZone:));
} else {
  ClassMethodCopy(cls, @selector(instrumentInstanceMessagesAddedAllocWithZone:),
      @selector(allocWithZone:));
}