Fix Wanders to be usable on its own

Allows unarmed actors like civilians or harmless critters to wander around when idle.

Additionally made it upgradable.

OpenRA.Mods.Common/Traits/Wanders.cs

@@ -15,7 +15,7 @@ using OpenRA.Traits;
 namespace OpenRA.Mods.Common.Traits
 {
 	[Desc("Wanders around aimlessly while idle.")]
-	public abstract class WandersInfo : ITraitInfo
+	public class WandersInfo : UpgradableTraitInfo, Requires<IMoveInfo>
 	{
 		public readonly int WanderMoveRadius = 1;
 
@@ -28,13 +28,14 @@ namespace OpenRA.Mods.Common.Traits
 		[Desc("Maximum amount of ticks the actor will sit idly before starting to wander.")]
 		public readonly int MaxMoveDelay = 0;
 
-		public abstract object Create(ActorInitializer init);
+		public override object Create(ActorInitializer init) { return new Wanders(init.Self, this); }
 	}
 
-	public class Wanders : INotifyIdle, INotifyBecomingIdle
+	public class Wanders : UpgradableTrait<WandersInfo>, INotifyCreated, INotifyIdle, INotifyBecomingIdle
 	{
 		readonly Actor self;
 		readonly WandersInfo info;
+		IResolveOrder move;
 
 		int countdown;
 		int ticksIdle;
@@ -42,12 +43,18 @@ namespace OpenRA.Mods.Common.Traits
 		bool firstTick = true;
 
 		public Wanders(Actor self, WandersInfo info)
+			: base(info)
 		{
 			this.self = self;
 			this.info = info;
 			effectiveMoveRadius = info.WanderMoveRadius;
 		}
 
+		void INotifyCreated.Created(Actor self)
+		{
+			move = self.Trait<IMove>() as IResolveOrder;
+		}
+
 		public virtual void OnBecomingIdle(Actor self)
 		{
 			countdown = self.World.SharedRandom.Next(info.MinMoveDelay, info.MaxMoveDelay);
@@ -55,6 +62,9 @@ namespace OpenRA.Mods.Common.Traits
 
 		public virtual void TickIdle(Actor self)
 		{
+			if (IsTraitDisabled)
+				return;
+
 			// OnBecomingIdle has not been called yet at this point, so set the initial countdown here
 			if (firstTick)
 			{
@@ -93,7 +103,7 @@ namespace OpenRA.Mods.Common.Traits
 
 		public virtual void DoAction(Actor self, CPos targetCell)
 		{
-			throw new NotImplementedException("Base class Wanders does not implement method DoAction!");
+			move.ResolveOrder(self, new Order("Move", self, false) { TargetLocation = targetCell });
 		}
 	}
 }