유니티엔진의 T Object.Instantiate<T>(T)는 큰 약점이 있는것만 같다

public static T Instantiate<T>(T original) where T : Object
{
  Object.CheckNullArgument((object) original, "The Object you want to instantiate is null.");
  T obj = (T) Object.Internal_CloneSingle((Object) original);
  return !((Object) obj == (Object) null) ? obj : throw new UnityException("Instantiate failed because the clone was destroyed during creation. This can happen if DestroyImmediate is called in MonoBehaviour.Awake.");
}

디컴파일하면 위와 같은데, 아무리 생각해도 맨 밑에 줄이 거슬린다

Object간의 ==연산자는 밑과 같이 오버로드 된다

public static bool operator ==(Object x, Object y) => Object.CompareBaseObjects(x, y);

private static bool CompareBaseObjects(Object lhs, Object rhs)
{
  bool flag1 = (object) lhs == null;
  bool flag2 = (object) rhs == null;
  if (flag2 & flag1)
    return true;
  if (flag2)
    return !Object.IsNativeObjectAlive(lhs);
  return flag1 ? !Object.IsNativeObjectAlive(rhs) : lhs.m_InstanceID == rhs.m_InstanceID;
}

private static bool IsNativeObjectAlive(Object o)
{
  if (o.GetCachedPtr() != IntPtr.Zero)
    return true;
  return !(o is MonoBehaviour) && !(o is ScriptableObject) && Object.DoesObjectWithInstanceIDExist(o.GetInstanceID());
}

[NativeMethod(IsFreeFunction = true, IsThreadSafe = true, Name = "UnityEngineObjectBindings::DoesObjectWithInstanceIDExist")]
[MethodImpl(MethodImplOptions.InternalCall)]
internal static extern bool DoesObjectWithInstanceIDExist(int instanceID);

저 작업들을 전부 수행하는건 귀찮으니 이렇게 바꿔주자

public static partial class ObjectUtility
{
    private delegate Object ObjectCopier(Object obj);

    private static ObjectCopier _copier;

    private static ObjectCopier Copier =>
        _copier ??= typeof(Object)
                   .GetMethod("Internal_CloneSingle")
                  ?.CreateDelegate(typeof(ObjectCopier))
            is ObjectCopier method
            ? method
            : Object.Instantiate;
    
    [method: MethodImpl(MethodImplOptions.AggressiveInlining)]
    public static Object CopyObject(this Object obj) => Copier(obj);
}

졸리니 테스트는 내일해야지...