Fix smoke fork bomb (#7401)

Content.Server/Chemistry/EntitySystems/SolutionAreaEffectSystem.cs

@@ -1,5 +1,7 @@
 using System.Linq;
 using Content.Server.Chemistry.Components;
+using Content.Server.Chemistry.ReactionEffects;
+using Content.Shared.Chemistry.Reaction;
 using JetBrains.Annotations;
 using Robust.Shared.GameObjects;
 
@@ -8,6 +10,13 @@ namespace Content.Server.Chemistry.EntitySystems
     [UsedImplicitly]
     public sealed class SolutionAreaEffectSystem : EntitySystem
     {
+        public override void Initialize()
+        {
+            base.Initialize();
+
+            SubscribeLocalEvent<SolutionAreaEffectComponent, ReactionAttemptEvent>(OnReactionAttempt);
+        }
+
         public override void Update(float frameTime)
         {
             foreach (var inception in EntityManager.EntityQuery<SolutionAreaEffectInceptionComponent>().ToArray())
@@ -15,5 +24,21 @@ namespace Content.Server.Chemistry.EntitySystems
                 inception.InceptionUpdate(frameTime);
             }
         }
+
+        private void OnReactionAttempt(EntityUid uid, SolutionAreaEffectComponent component, ReactionAttemptEvent args)
+        {
+            if (args.Solution.Name != SolutionAreaEffectComponent.SolutionName)
+                return;
+
+            // Prevent smoke/foam fork bombs (smoke creating more smoke).
+            foreach (var effect in args.Reaction.Effects)
+            {
+                if (effect is AreaReactionEffect)
+                {
+                    args.Cancel();
+                    return;
+                }
+            }
+        }
     }
 }