Fix disposals trapping you for eternity when leaving via a trunk pipe (#5498)

Content.Server/Disposal/Unit/Components/DisposalHolderComponent.cs

@@ -56,6 +56,10 @@ namespace Content.Server.Disposal.Unit.Components
         [ViewVariables]
         public Direction CurrentDirection { get; set; } = Direction.Invalid;
 
+        /// <summary>Mistake prevention</summary>
+        [ViewVariables]
+        public bool IsExitingDisposals { get; set; } = false;
+
         /// <summary>
         ///     A list of tags attached to the content, used for sorting
         /// </summary>

Content.Server/Disposal/Unit/EntitySystems/DisposableSystem.cs

@@ -9,6 +9,7 @@ using Robust.Shared.Containers;
 using Robust.Shared.GameObjects;
 using Robust.Shared.IoC;
 using Robust.Shared.Map;
+using Robust.Shared.Log;
 using Robust.Shared.Maths;
 using Robust.Shared.Physics;
 
@@ -25,6 +26,12 @@ namespace Content.Server.Disposal.Unit.EntitySystems
         {
             if (!Resolve(uid, ref holder, ref holderTransform))
                 return;
+            if (holder.IsExitingDisposals)
+            {
+                Logger.ErrorS("c.s.disposal.holder", "Tried exiting disposals twice. This should never happen.");
+                return;
+            }
+            holder.IsExitingDisposals = true;
 
             // Check for a disposal unit to throw them into and then eject them from it.
             // *This ejection also makes the target not collide with the unit.*
@@ -83,6 +90,11 @@ namespace Content.Server.Disposal.Unit.EntitySystems
         {
             if (!Resolve(holderUid, ref holder, ref holderTransform))
                 return false;
+            if (holder.IsExitingDisposals)
+            {
+                Logger.ErrorS("c.s.disposal.holder", "Tried entering tube after exiting disposals. This should never happen.");
+                return false;
+            }
             if (!Resolve(toUid, ref to, ref toTransform))
             {
                 ExitDisposals(holderUid, holder, holderTransform);
@@ -102,19 +114,19 @@ namespace Content.Server.Disposal.Unit.EntitySystems
                 holder.PreviousTube = holder.CurrentTube;
                 holder.PreviousDirection = holder.CurrentDirection;
             }
-            var dir = to.NextDirection(holder);
+            holderTransform.Coordinates = toTransform.Coordinates;
+            holder.CurrentTube = to;
+            holder.CurrentDirection = to.NextDirection(holder);
+            holder.StartingTime = 0.1f;
+            holder.TimeLeft = 0.1f;
+            // Logger.InfoS("c.s.disposal.holder", $"Disposals dir {holder.CurrentDirection}");
+
             // Invalid direction = exit now!
-            if (dir == Direction.Invalid)
+            if (holder.CurrentDirection == Direction.Invalid)
             {
                 ExitDisposals(holderUid, holder, holderTransform);
                 return false;
             }
-
-            holderTransform.Coordinates = toTransform.Coordinates;
-            holder.CurrentTube = to;
-            holder.CurrentDirection = dir;
-            holder.StartingTime = 0.1f;
-            holder.TimeLeft = 0.1f;
             return true;
         }
 
@@ -173,7 +185,6 @@ namespace Content.Server.Disposal.Unit.EntitySystems
                 // Perform remainder of entry process
                 if (!EnterTube(holder.OwnerUid, nextTube.OwnerUid, holder, null, nextTube, null))
                 {
-                    ExitDisposals(holder.OwnerUid);
                     break;
                 }
             }