bring back ReadsPending attribute

encompass-cs/Attributes/Reads.cs

@@ -22,7 +22,6 @@ namespace Encompass
                 }
 
                 this.readTypes.Add(typeof(ComponentMessage<>).MakeGenericType(readType));
-                this.readTypes.Add(typeof(PendingComponentMessage<>).MakeGenericType(readType));
             }
         }
     }

encompass-cs/Attributes/ReadsPending.cs

@@ -0,0 +1,28 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using Encompass.Exceptions;
+
+namespace Encompass
+{
+    [AttributeUsage(AttributeTargets.Class)]
+    public class ReadsPending : Attribute
+    {
+        public readonly HashSet<Type> readPendingTypes = new HashSet<Type>();
+
+        public ReadsPending(params Type[] readPendingTypes)
+        {
+            foreach (var readPendingType in readPendingTypes)
+            {
+                var isComponent = readPendingType.GetInterfaces().Contains(typeof(IComponent));
+
+                if (!isComponent)
+                {
+                    throw new IllegalReadTypeException("{0} must be a Component", readPendingType.Name);
+                }
+
+                this.readPendingTypes.Add(typeof(PendingComponentMessage<>).MakeGenericType(readPendingType));
+            }
+        }
+    }
+}

encompass-cs/Engine.cs

@@ -46,6 +46,12 @@ namespace Encompass
             {
                 receiveTypes.UnionWith(readsAttribute.readTypes);
             }
+
+            var readsPendingAttribute = GetType().GetCustomAttribute<ReadsPending>(false);
+            if (readsPendingAttribute != null)
+            {
+                receiveTypes.UnionWith(readsPendingAttribute.readPendingTypes);
+            }
         }
 
         internal void AssignEntityManager(EntityManager entityManager)
@@ -181,6 +187,14 @@ namespace Encompass
             {
                 return ExistingComponents<TComponent>().Union(PendingComponents<TComponent>());
             }
+            else if (existingRead)
+            {
+                return ExistingComponents<TComponent>();
+            }
+            else if (pendingRead)
+            {
+                return PendingComponents<TComponent>();
+            }
             else
             {
                 throw new IllegalReadException("Engine {0} tried to read undeclared Component {1}", GetType().Name, typeof(TComponent).Name);
@@ -217,11 +231,6 @@ namespace Encompass
             return ExistingComponentsOnEntity<TComponent>(entity);
         }
 
-        protected ValueTuple<Guid, TComponent> GetPendingComponent<TComponent>(Entity entity) where TComponent : struct, IComponent
-        {
-            return PendingComponentsOnEntity<TComponent>(entity).First();
-        }
-
         protected ValueTuple<Guid, TComponent> GetComponent<TComponent>(Entity entity) where TComponent : struct, IComponent
         {
             return GetComponents<TComponent>(entity).First();
@@ -232,11 +241,6 @@ namespace Encompass
             return GetComponents<TComponent>(entity).Any();
         }
 
-        internal void ActivateComponentInWorld(Guid componentID)
-        {
-            componentManager.Activate(componentID);
-        }
-
         internal void UpdateComponentInWorld<TComponent>(Guid componentID, TComponent newComponent) where TComponent : struct, IComponent
         {
             componentManager.AddUpdateComponentOperation(componentID, newComponent);

test/ComponentTest.cs

@@ -123,7 +123,7 @@ namespace Tests
             }
         }
 
-        [Reads(typeof(MockComponent))]
+        [ReadsPending(typeof(MockComponent))]
         class HasMockComponentEngine : Engine
         {
             private Entity entity;
@@ -481,7 +481,7 @@ namespace Tests
         }
 
         [Receives(typeof(CheckHasMockComponentMessage))]
-        [Reads(typeof(MockComponent))]
+        [ReadsPending(typeof(MockComponent))]
         class CheckHasPendingMockComponentEngine : Engine
         {
             public override void Update(double dt)