void Check(bool value,string message){if(!value)throw new Exception(message);}
foreach(var scenario in new[]{"normal","destroyed","replaced"}){
 GContext.container=new Container();Awaiters.Gate=new();var old=GContext.container;var panel=new Subject();
 var pending=panel.LastShowPanel();Check(!pending.IsCompleted,"expected delay");
 if(scenario=="destroyed")panel.Destroyed=true;
 if(scenario=="replaced")GContext.container=new Container();
 Awaiters.Gate.SetResult(true);await pending;
 Check(old.Face.Shows==(scenario=="normal"?1:0),"old flow applied after exit");
 if(scenario=="replaced")Check(GContext.container.Face.Shows==0,"old callback opened new account UI");
 Check(Debug.Errors==0,"callback logged an error");
 Console.WriteLine("PASS real LastShowPanel body: "+scenario);
}
public partial class Subject{
 public bool Destroyed;
 public static bool operator ==(Subject a,Subject b)=>ReferenceEquals(b,null)?ReferenceEquals(a,null)||a.Destroyed:ReferenceEquals(a,b);
 public static bool operator !=(Subject a,Subject b)=>!(a==b);
 public override bool Equals(object other)=>ReferenceEquals(this,other);
 public override int GetHashCode()=>base.GetHashCode();
}
public static class GContext{public static Container container=new();}
public class Container{
 public Face Face=new();public BuffDataCenter Buff=new();
 public T Resolve<T>()=>(T)(object)(typeof(T)==typeof(BuffDataCenter)?(object)Buff:Face);
}
public class BuffDataCenter{public List<int> showFishBuffIds=new();}
public interface IFaceUIService{void ShowPostFaceUI();}
public class Face:IFaceUIService{public int Shows;public void ShowPostFaceUI()=>Shows++;}
public static class Awaiters{public static TaskCompletionSource<bool> Gate;public static Task Seconds(float n)=>Gate.Task;}
public static class Debug{public static int Errors;public static void LogError(object e)=>Errors++;}