Avoid units continuing to follow the unattackable targets

OpenRA.Mods.Common/Activities/Air/FlyAttack.cs

@@ -43,6 +43,7 @@ namespace OpenRA.Mods.Common.Activities
 			this.target = target;
 			this.forceAttack = forceAttack;
 			this.targetLineColor = targetLineColor;
+			ChildHasPriority = false;
 
 			aircraft = self.Trait<Aircraft>();
 			attackAircraft = self.Trait<AttackAircraft>();
@@ -73,6 +74,12 @@ namespace OpenRA.Mods.Common.Activities
 
 		public override bool Tick(Actor self)
 		{
+			if (!IsCanceling && !HasArmamentsFor(target))
+				Cancel(self, true);
+
+			if (!TickChild(self))
+				return false;
+
 			returnToBase = false;
 
 			// Refuse to take off if it would land immediately again.
@@ -198,6 +205,11 @@ namespace OpenRA.Mods.Common.Activities
 					yield return new TargetLineNode(useLastVisibleTarget ? lastVisibleTarget : target, targetLineColor.Value);
 			}
 		}
+
+		bool HasArmamentsFor(Target target)
+		{
+			return !attackAircraft.IsTraitDisabled && attackAircraft.ChooseArmamentsForTarget(target, forceAttack).Any();
+		}
 	}
 
 	sealed class FlyAttackRun : Activity

OpenRA.Mods.Common/Activities/Attack.cs

@@ -51,6 +51,7 @@ namespace OpenRA.Mods.Common.Activities
 			this.target = target;
 			this.targetLineColor = targetLineColor;
 			this.forceAttack = forceAttack;
+			ChildHasPriority = false;
 
 			attackTraits = self.TraitsImplementing<AttackFrontal>().ToArray().Where(t => !t.IsTraitDisabled);
 			revealsShroud = self.TraitsImplementing<RevealsShroud>().ToArray();
@@ -94,15 +95,15 @@ namespace OpenRA.Mods.Common.Activities
 
 		public override bool Tick(Actor self)
 		{
+			if (!IsCanceling && !HasArmamentsFor(target))
+				Cancel(self, true);
+
+			if (!TickChild(self))
+				return false;
+
 			if (IsCanceling)
 				return true;
 
-			if (!attackTraits.Any())
-			{
-				Cancel(self);
-				return false;
-			}
-
 			target = RecalculateTarget(self, out var targetIsHiddenActor);
 
 			if (!targetIsHiddenActor && target.Type == TargetType.Actor)
@@ -273,5 +274,10 @@ namespace OpenRA.Mods.Common.Activities
 			if (targetLineColor != null)
 				yield return new TargetLineNode(useLastVisibleTarget ? lastVisibleTarget : target, targetLineColor.Value);
 		}
+
+		bool HasArmamentsFor(Target target)
+		{
+			return attackTraits.Any(attack => attack.ChooseArmamentsForTarget(target, forceAttack).Any());
+		}
 	}
 }

OpenRA.Mods.Common/Traits/Attack/AttackFollow.cs

@@ -263,6 +263,7 @@ namespace OpenRA.Mods.Common.Traits
 				this.targetLineColor = targetLineColor;
 				this.source = source;
 				isAircraft = self.Info.HasTraitInfo<AircraftInfo>();
+				ChildHasPriority = false;
 
 				// The target may become hidden between the initial order request and the first tick (e.g. if queued)
 				// Moving to any position (even if quite stale) is still better than immediately giving up
@@ -288,6 +289,12 @@ namespace OpenRA.Mods.Common.Traits
 
 			public override bool Tick(Actor self)
 			{
+				if (!IsCanceling && !HasArmamentsFor(target))
+					Cancel(self, true);
+
+				if (!TickChild(self))
+					return false;
+
 				returnToBase = false;
 
 				if (IsCanceling)
@@ -440,6 +447,11 @@ namespace OpenRA.Mods.Common.Traits
 						yield return new TargetLineNode(useLastVisibleTarget ? lastVisibleTarget : target, targetLineColor.Value);
 				}
 			}
+
+			bool HasArmamentsFor(Target target)
+			{
+				return !attack.IsTraitDisabled && attack.ChooseArmamentsForTarget(target, forceAttack).Any();
+			}
 		}
 	}
 }