为Singleton类编写AllocWithZone方法的单元测试用例

Question

我有单元测试方法

-(void)setUp
{
    objectofClass=[ClassName shared];
}

-(void) testAllocWithZone
{
     STAssertNClassName *oneMoreObject=nil;oThrow(oneMoreObject=[ClassName allocWithZone:NSDefaultZone()],testing);
}

oneMoreObject的值应该是多少？ 它是nil还是sharedObject .. ???