Client entity deletion error tolerance (#3435)

Robust.Client/GameObjects/ClientEntityManager.cs

@@ -31,6 +31,17 @@ namespace Robust.Client.GameObjects
 
             base.Initialize();
         }
+        public override void Shutdown()
+        {
+            using var _ = _gameTiming.StartStateApplicationArea();
+            base.Shutdown();
+        }
+
+        public override void Cleanup()
+        {
+            using var _ = _gameTiming.StartStateApplicationArea();
+            base.Cleanup();
+        }
 
         EntityUid IClientEntityManagerInternal.CreateEntity(string? prototypeName, EntityUid uid)
         {

Robust.Client/GameStates/ClientDirtySystem.cs

@@ -1,8 +1,10 @@
-using System.Collections.Generic;
 using Robust.Client.Timing;
 using Robust.Shared.GameObjects;
 using Robust.Shared.IoC;
+using Robust.Shared.Log;
 using Robust.Shared.Utility;
+using System;
+using System.Collections.Generic;
 
 namespace Robust.Client.GameStates;
 
@@ -23,6 +25,7 @@ internal sealed class ClientDirtySystem : EntitySystem
     public override void Initialize()
     {
         base.Initialize();
+        SubscribeLocalEvent<EntityTerminatingEvent>(OnTerminate);
         EntityManager.EntityDirtied += OnEntityDirty;
         EntityManager.ComponentRemoved += OnCompRemoved;
     }
@@ -35,6 +38,15 @@ internal sealed class ClientDirtySystem : EntitySystem
         Reset();
     }
 
+    private void OnTerminate(ref EntityTerminatingEvent ev)
+    {
+        if (!_timing.InPrediction || ev.Entity.IsClientSide())
+            return;
+
+        // Client-side entity deletion is not supported and will cause errors.
+        Logger.Error($"Predicting the deletion of a networked entity: {ToPrettyString(ev.Entity)}. Trace: {Environment.StackTrace}");
+    }
+
     private void OnCompRemoved(RemovedComponentEventArgs args)
     {
         if (args.Terminating)

Robust.Client/GameStates/ClientGameStateManager.cs

@@ -249,7 +249,18 @@ namespace Robust.Client.GameStates
                 }
 
                 if (PredictionNeedsResetting)
-                    ResetPredictedEntities();
+                {
+                    try
+                    {
+                        ResetPredictedEntities();
+                    }
+                    catch
+                    {
+                        // avoid exception spam from repeatedly trying to reset the same entity.
+                        _entitySystemManager.GetEntitySystem<ClientDirtySystem>().Reset();
+                        throw;
+                    }
+                }
 
                 // If we were waiting for a new state, we are now applying it.
                 if (_processor.LastFullStateRequested.HasValue)
@@ -463,7 +474,11 @@ namespace Robust.Client.GameStates
 
                 countReset += 1;
 
-                foreach (var (netId, comp) in _entityManager.GetNetComponents(entity))
+                var netComps = _entityManager.GetNetComponentsOrNull(entity);
+                if (netComps == null)
+                    return;
+
+                foreach (var (netId, comp) in netComps.Value)
                 {
                     DebugTools.AssertNotNull(netId);
                     if (!comp.NetSyncEnabled)

Robust.Shared/GameObjects/EntityManager.Components.cs

@@ -952,6 +952,14 @@ namespace Robust.Shared.GameObjects
             return new NetComponentEnumerable(_netComponents[uid]);
         }
 
+        /// <inheritdoc />
+        public NetComponentEnumerable? GetNetComponentsOrNull(EntityUid uid)
+        {
+            return _netComponents.TryGetValue(uid, out var data)
+                    ? new NetComponentEnumerable(data)
+                    : null;
+        }
+
         #region Join Functions
 
         public AllEntityQueryEnumerator<TComp1> AllEntityQueryEnumerator<TComp1>()

Robust.Shared/GameObjects/EntityManager.cs

@@ -113,7 +113,7 @@ namespace Robust.Shared.GameObjects
             Started = false;
         }
 
-        public void Cleanup()
+        public virtual void Cleanup()
         {
             _componentFactory.ComponentAdded -= OnComponentAdded;
             _componentFactory.ComponentReferenceAdded -= OnComponentReferenceAdded;
@@ -345,8 +345,8 @@ namespace Robust.Shared.GameObjects
 
             try
             {
-                var ev = new EntityTerminatingEvent();
-                EventBus.RaiseLocalEvent(uid, ref ev);
+                var ev = new EntityTerminatingEvent(uid);
+                EventBus.RaiseLocalEvent(uid, ref ev, true);
             }
             catch (Exception e)
             {

Robust.Shared/GameObjects/EntitySystemMessages/EntityTerminatingEvent.cs

@@ -6,5 +6,11 @@ namespace Robust.Shared.GameObjects
     [ByRefEvent]
     public readonly struct EntityTerminatingEvent
     {
+        public readonly EntityUid Entity;
+
+        public EntityTerminatingEvent(EntityUid entity)
+        {
+            Entity = entity;
+        }
     }
 }

Robust.Shared/GameObjects/IEntityManager.Components.cs

@@ -358,6 +358,14 @@ namespace Robust.Shared.GameObjects
         /// <returns>All components that have a network ID.</returns>
         NetComponentEnumerable GetNetComponents(EntityUid uid);
 
+        /// <summary>
+        ///     Returns ALL networked components on an entity, including deleted ones. Returns null if the entity does
+        ///     not exist.
+        /// </summary>
+        /// <param name="uid">Entity UID to look on.</param>
+        /// <returns>All components that have a network ID.</returns>
+        public NetComponentEnumerable? GetNetComponentsOrNull(EntityUid uid);
+
         /// <summary>
         ///     Gets a component state.
         /// </summary>