CreateEntity() public method

public CreateEntity ( ) : Entity
return Entity
Example #1
0
    public void ensures_same_deterministic_order_when_getting_entities_after_DestroyAllEntities()
    {
        var context = new Context(1);

        const int numEntities = 10;
        for (int i = 0; i < numEntities; i++) {
            context.CreateEntity();
        }

        var order1 = new int[numEntities];
        var entities1 = context.GetEntities();
        for (int i = 0; i < numEntities; i++) {
            order1[i] = entities1[i].creationIndex;
        }

        context.DestroyAllEntities();
        context.ResetCreationIndex();

        for (int i = 0; i < numEntities; i++) {
            context.CreateEntity();
        }

        var order2 = new int[numEntities];
        var entities2 = context.GetEntities();
        for (int i = 0; i < numEntities; i++) {
            order2[i] = entities2[i].creationIndex;
        }

        for (int i = 0; i < numEntities; i++) {
            var index1 = order1[i];
            var index2 = order2[i];

            Assert.AreEqual(index1, index2);
        }
    }
 public void Before()
 {
     _context = Helper.CreateContext();
     for (int i = 0; i < n; i++) {
         _context.CreateEntity();
     }
     _e = _context.CreateEntity();
 }
 public void Before()
 {
     _context = Helper.CreateContext();
     _context.GetGroup(Matcher.AllOf(new [] { CP.ComponentA }));
     _e = _context.CreateEntity();
     _e.AddComponent(CP.ComponentA, new ComponentA());
 }
    public void Before()
    {
        _context = Helper.CreateContext();
        _index = new PrimaryEntityIndex<string>(_context.GetGroup(Matcher.AllOf(CP.ComponentA)), (e, c) => ((NameComponent)c).name);

        for (int i = 0; i < 10; i++) {
            var nameComponent = new NameComponent();
            nameComponent.name = i.ToString();
            _context.CreateEntity().AddComponent(CP.ComponentA, nameComponent);
        }
    }
        /// <summary>
        /// Create a Scene Entity (drawn on top of game scene e.g. UI entity)
        /// </summary>
        /// <returns></returns>
        public Entity CreateSceneEntity(string name = "", float initScale = 1.0f)
        {
            //
            // Create the entity at Vector2(0,0), Scale 1.0f
            //
            Entity ent = SceneContext.CreateEntity();

            ent.EntityType = 1;                 //scene entity type
            ent.Name       = name;
            //
            // fix the Transform
            //
            Transform trm = new Transform();

            trm.Scale    = new Vector2(initScale, initScale);
            trm.Rotation = 0;
            ent.Add(trm);

            return(ent);
        }
    public void Before()
    {
        _context = Helper.CreateContext();

        var e = _context.CreateEntity();
        var component = new NameAgeComponent();
        component.name = "Max";
        component.age = 42;
        e.AddComponent(CP.ComponentA, component);

        _blueprint = new Blueprint(string.Empty, string.Empty, e);
    }
    void when_entity()
    {
        context["when adding ComponentSuffix"] = () => {

            it["doesn't add component suffix to string ending with ComponentSuffix"] = () => {
                const string str = "Position" + EntityExtension.COMPONENT_SUFFIX;
                str.AddComponentSuffix().should_be_same(str);
            };

            it["add ComponentSuffix to string not ending with ComponentSuffix"] = () => {
                const string str = "Position";
                str.AddComponentSuffix().should_be("Position" + EntityExtension.COMPONENT_SUFFIX);
            };
        };

        context["when removeing ComponentSuffix"] = () => {

            it["doesn't change string when not ending with ComponentSuffix"] = () => {
                const string str = "Position";
                str.RemoveComponentSuffix().should_be_same(str);
            };

            it["removes ComponentSuffix when ending with ComponentSuffix"] = () => {
                const string str = "Position" + EntityExtension.COMPONENT_SUFFIX;
                str.RemoveComponentSuffix().should_be("Position");
            };
        };

        context["when copying components"] = () => {

            Context ctx = null;
            Entity entity = null;
            Entity target = null;
            NameAgeComponent nameAge = null;

            before = () => {
                ctx = new Context(CID.TotalComponents);
                entity = ctx.CreateEntity();
                target = ctx.CreateEntity();
                nameAge = new NameAgeComponent { name = "Max", age = 42 };
            };

            it["doesn't change entity if original doesn't have any components"] = () => {
                entity.CopyTo(target);

                entity.creationIndex.should_be(0);
                target.creationIndex.should_be(1);

                target.GetComponents().Length.should_be(0);
            };

            it["adds copies of all components to target entity"] = () => {
                entity.AddComponentA();
                entity.AddComponent(CID.ComponentB, nameAge);

                entity.CopyTo(target);

                target.GetComponents().Length.should_be(2);
                target.HasComponentA().should_be_true();
                target.HasComponentB().should_be_true();
                target.GetComponentA().should_not_be_same(Component.A);
                target.GetComponent(CID.ComponentB).should_not_be_same(nameAge);

                var clonedComponent = (NameAgeComponent)target.GetComponent(CID.ComponentB);

                clonedComponent.name.should_be(nameAge.name);
                clonedComponent.age.should_be(nameAge.age);
            };

            it["throws when target already has a component at index"] = base.expect<EntityAlreadyHasComponentException>(() => {
                entity.AddComponentA();
                entity.AddComponent(CID.ComponentB, nameAge);
                var component = new NameAgeComponent();
                target.AddComponent(CID.ComponentB, component);

                entity.CopyTo(target);
            });

            it["replaces existing components when overwrite is set"] = () => {
                entity.AddComponentA();
                entity.AddComponent(CID.ComponentB, nameAge);
                var component = new NameAgeComponent();
                target.AddComponent(CID.ComponentB, component);

                entity.CopyTo(target, true);

                var copy = target.GetComponent(CID.ComponentB);
                copy.should_not_be_same(nameAge);
                copy.should_not_be_same(component);
                ((NameAgeComponent)copy).name.should_be(nameAge.name);
                ((NameAgeComponent)copy).age.should_be(nameAge.age);
            };

            it["only adds copies of specified components to target entity"] = () => {
                entity.AddComponentA();
                entity.AddComponentB();
                entity.AddComponentC();

                entity.CopyTo(target, false, CID.ComponentB, CID.ComponentC);

                target.GetComponents().Length.should_be(2);
                target.HasComponentB().should_be_true();
                target.HasComponentC().should_be_true();
            };

            it["uses component pool"] = () => {
                entity.AddComponentA();

                var component = new ComponentA();
                target.GetComponentPool(CID.ComponentA).Push(component);

                entity.CopyTo(target);

                target.GetComponentA().should_be_same(component);
            };
        };
    }
    void when_creating()
    {
        Context ctx = null;
        Entity entity = null;

        before = () => {
            ctx = new Context(CID.TotalComponents);
            entity = ctx.CreateEntity();
        };

        context["ComponentBlueprint"] = () => {

            it["creates a component blueprint from a component without members"] = () => {
                var component = new ComponentA();

                const int index = 42;

                var componentBlueprint = new ComponentBlueprint(index, component);
                componentBlueprint.index.should_be(index);
                componentBlueprint.fullTypeName.should_be(component.GetType().FullName);
                componentBlueprint.members.Length.should_be(0);
            };

            it["throws when unknown type"] = expect<ComponentBlueprintException>(() => {
                var componentBlueprint = new ComponentBlueprint();
                componentBlueprint.fullTypeName = "UnknownType";
                componentBlueprint.CreateComponent(null);
            });

            it["throws when type doesn't implement IComponent"] = expect<ComponentBlueprintException>(() => {
                var componentBlueprint = new ComponentBlueprint();
                componentBlueprint.fullTypeName = "string";
                componentBlueprint.CreateComponent(null);
            });

            it["creates a component blueprint from a component with members"] = () => {
                var component = new NameAgeComponent();
                component.name = "Max";
                component.age = 42;

                const int index = 24;

                var componentBlueprint = new ComponentBlueprint(index, component);
                componentBlueprint.index.should_be(index);
                componentBlueprint.fullTypeName.should_be(component.GetType().FullName);
                componentBlueprint.members.Length.should_be(2);

                componentBlueprint.members[0].name.should_be("name");
                componentBlueprint.members[0].value.should_be(component.name);

                componentBlueprint.members[1].name.should_be("age");
                componentBlueprint.members[1].value.should_be(component.age);
            };

            it["creates a component and sets members values"] = () => {
                var componentBlueprint = new ComponentBlueprint();
                componentBlueprint.fullTypeName = typeof(ComponentWithFieldsAndProperties).FullName;
                componentBlueprint.index = CID.ComponentB;
                componentBlueprint.members = new [] {
                    new SerializableMember("publicField", "publicFieldValue"),
                    new SerializableMember("publicProperty", "publicPropertyValue")
                };

                var component = (ComponentWithFieldsAndProperties)componentBlueprint.CreateComponent(entity);
                component.publicField.should_be("publicFieldValue");
                component.publicProperty.should_be("publicPropertyValue");
            };

            it["throws when invalid member name"] = expect<ComponentBlueprintException>(() => {
                var componentBlueprint = new ComponentBlueprint();
                componentBlueprint.index = 0;
                componentBlueprint.fullTypeName = typeof(NameAgeComponent).FullName;
                componentBlueprint.members = new [] {
                    new SerializableMember("xxx", "publicFieldValue"),
                    new SerializableMember("publicProperty", "publicPropertyValue")
                };
                componentBlueprint.CreateComponent(entity);
            });
        };

        context["Blueprint"] = () => {

            it["creates a blueprint from an entity"] = () => {
                entity.AddComponentA();

                var component = new NameAgeComponent();
                component.name = "Max";
                component.age = 42;

                entity.AddComponent(CID.ComponentB, component);

                var blueprint = new Blueprint("My Context", "Hero", entity);
                blueprint.contextIdentifier.should_be("My Context");
                blueprint.name.should_be("Hero");
                blueprint.components.Length.should_be(2);

                blueprint.components[0].index.should_be(CID.ComponentA);
                blueprint.components[0].fullTypeName.should_be(Component.A.GetType().FullName);

                blueprint.components[1].index.should_be(CID.ComponentB);
                blueprint.components[1].fullTypeName.should_be(component.GetType().FullName);
            };

            context["when applying blueprint"] = () => {

                Blueprint blueprint = null;

                before = () => {
                    var component1 = new ComponentBlueprint();
                    component1.index = CID.ComponentA;
                    component1.fullTypeName = typeof(ComponentA).FullName;
                    component1.members = new SerializableMember[0];

                    var component2 = new ComponentBlueprint();
                    component2.index = CID.ComponentB;
                    component2.fullTypeName = typeof(NameAgeComponent).FullName;
                    component2.members = new [] {
                        new SerializableMember("name", "Max"),
                        new SerializableMember("age", 42)
                    };

                    blueprint = new Blueprint();
                    blueprint.name = "Hero";
                    blueprint.components = new [] { component1, component2 };
                };

                it["applies blueprint to entity"] = () => {
                    entity.ApplyBlueprint(blueprint).should_be(entity);

                    entity.GetComponents().Length.should_be(2);

                    entity.GetComponent(CID.ComponentA).GetType().should_be(typeof(ComponentA));

                    var nameAgeComponent = (NameAgeComponent)entity.GetComponent(CID.ComponentB);
                    nameAgeComponent.GetType().should_be(typeof(NameAgeComponent));
                    nameAgeComponent.name.should_be("Max");
                    nameAgeComponent.age.should_be(42);
                };

                it["throws when entity already has a component which should be added from blueprint"] = expect<EntityAlreadyHasComponentException>(() => {
                    entity.AddComponentA();
                    entity.ApplyBlueprint(blueprint);
                });

                it["can overwrite existing components"] = () => {
                    var nameAgeComponent = new NameAgeComponent();
                    nameAgeComponent.name = "Jack";
                    nameAgeComponent.age = 24;
                    entity.AddComponent(CID.ComponentB, nameAgeComponent);

                    entity.ApplyBlueprint(blueprint, true);
                };

                it["uses component from componentPool"] = () => {
                    var component = new ComponentBlueprint();
                    component.index = CID.ComponentA;
                    component.fullTypeName = typeof(ComponentA).FullName;
                    component.members = new SerializableMember[0];

                    blueprint = new Blueprint();
                    blueprint.name = "Hero";
                    blueprint.components = new [] { component };

                    var componentA = entity.CreateComponent<ComponentA>(CID.ComponentA);
                    entity.AddComponent(CID.ComponentA, componentA);
                    entity.RemoveComponentA();

                    entity.ApplyBlueprint(blueprint);

                    entity.GetComponentA().should_be_same(componentA);
                };
            };
        };
    }
    void createTestEntityWithNullValues(Context context)
    {
        var e = context.CreateEntity();

        // Unity's builtIn
        AnimationCurve animationCurve = null;
        e.AddAnimationCurve(animationCurve);
        string myString = null;
        e.AddMyString(myString);
        UnityEngine.Object unityObject = null;
        e.AddUnityObject(unityObject);
        GameObject go = null;
        e.AddGameObject(go);
        Texture texture = null;
        e.AddTexture(texture);
        Texture2D texture2D = null;
        e.AddTexture2D(texture2D);

        // Custom
        MonoBehaviourSubClass monoBehaviourSubClass = null;
        e.AddMonoBehaviourSubClass(monoBehaviourSubClass);
        CustomObject customObject = null;
        e.AddCustomObject(customObject);
        object systemObject = null;
        e.AddSystemObject(systemObject);
        string[] array = null;
        e.AddAnArray(array);
        string[,] array2d = null;
        e.AddArray2D(array2d);
        string[,,] array3d = null;
        e.AddArray3D(array3d);
        string[][] jaggedArray = null;
        e.AddJaggedArray(jaggedArray);
        List<string>[] listArray = null;
        e.AddListArray(listArray);
        List<string> list = null;
        e.AddList(list);
        Dictionary<string, string> dict = null;
        e.AddDictionary(dict);
        Dictionary<int, string[]> dict2 = null;
        Dictionary<int, string[]>[] dictArray = null;
        e.AddDictArray(dict2, dictArray);
        HashSet<string> hashset = null;
        e.AddHashSet(hashset);
        char c = default(char);
        e.AddMyChar(c);
        UnsupportedObject unsupportedObject = null;
        e.AddUnsupportedObject(unsupportedObject);
        e.AddProperty(myString);
        string personName = null;
        string personGender = null;
        e.AddPerson(personName, personGender);
    }
 void createTestEntityError(Context context)
 {
     context.DestroyEntity(context.CreateEntity().Retain(this));
 }
    void createTestEntities(Context context)
    {
        for (int i = 0; i < 2; i++) {
            var e = context.CreateEntity();

            // Unity's builtIn
            e.AddBounds(new Bounds());
            e.AddColor(Color.red);
            e.AddAnimationCurve(AnimationCurve.EaseInOut(0f, 0f, 1f, 1f));
            e.AddMyEnum(MyEnumComponent.MyEnum.Item2);
            e.AddMyFlags(MyFlagsComponent.MyFlags.Item2);
            e.AddMyDouble(4.2f);
            e.AddMyFloat(4.2f);
            e.AddMyInt(42);
            e.AddRect(new Rect(1f, 2f, 3f, 4f));
            e.AddMyString("Hello, world!");
            e.AddVector2(new Vector2(1f, 2f));
            e.AddVector3(new Vector3(1f, 2f, 3f));
            e.AddVector4(new Vector4(1f, 2f, 3f, 4f));
            e.AddMyBool(true);
            e.AddUnityObject(new UnityEngine.Object());
            e.AddGameObject(new GameObject("Player"));
            e.AddTexture(new Texture());
            e.AddTexture2D(new Texture2D(2, 2));

            // Custom
            e.AddMonoBehaviourSubClass(new GameObject().AddComponent<MonoBehaviourSubClass>());
            e.AddCustomObject(new CustomObject("Custom Object"));
            e.AddSystemObject(new object());
            e.AddDateTime(DateTime.Now);
            e.AddAnArray(new [] { "Hello", ", ", "world", "!" });
            e.AddArray2D(new string[2, 3]);
            e.AddArray3D(new string[2, 3, 4]);
            string[][] jaggedArray = new string[2][];
            jaggedArray[0] = new [] { "Entity", "Component", "System" };
            jaggedArray[1] = new [] { "For", "C#" };
            e.AddJaggedArray(jaggedArray);
            var listArray = new List<string>[] {
                new List<string> { "1", "2", "3" },
                new List<string> { "One", "Two", "Three" }
            };
            e.AddListArray(listArray);
            e.AddList(new List<string>{ "Apple", "Banana", "Peach" });
            var dict = new Dictionary<string, string> {
                { "1", "One" },
                { "2", "Two" },
                { "3", "Three" },
            };
            e.AddDictionary(dict);
            var dict2 = new Dictionary<int, string[]> {
                { 1, new [] { "One", "Two", "Three" } },
                { 2, new [] { "Four", "Five", "Six" } }
            };
            var dictArray = new Dictionary<int, string[]>[] {
                new Dictionary<int, string[]> {
                    { 1, new [] { "One", "Two", "Three" } },
                    { 2, new [] { "Four", "Five", "Six" } }
                }, new Dictionary<int, string[]> {
                    { 3, new [] { "One", "Two", "Three" } },
                    { 4, new [] { "Four", "Five", "Six" } }
                }
            };
            e.AddDictArray(dict2, dictArray);
            e.AddHashSet(new HashSet<string> { "One", "Two", "Three" });
            e.AddMyChar('c');
            e.AddUnsupportedObject(new UnsupportedObject("Unsupported Object"));
            e.AddProperty("My Property");
            e.AddPerson("Max", "Male");
        }
    }
    void when_created()
    {
        Context ctx = null;

        before = () => {
            ctx = new Context(CID.TotalComponents);
        };

        it["increments creationIndex"] = () => {
            ctx.CreateEntity().creationIndex.should_be(0);
            ctx.CreateEntity().creationIndex.should_be(1);
        };

        it["starts with given creationIndex"] = () => {
            new Context(CID.TotalComponents, 42, null).CreateEntity().creationIndex.should_be(42);
        };

        it["has no entities when no entities were created"] = () => {
            ctx.GetEntities().should_be_empty();
        };

        it["gets total entity count"] = () => {
            ctx.count.should_be(0);
        };

        it["creates entity"] = () => {
            var e = ctx.CreateEntity();
            e.should_not_be_null();
            e.GetType().should_be(typeof(Entity));
        };

        it["has default ContextInfo"] = () => {
            ctx.contextInfo.name.should_be("Unnamed Context");
            ctx.contextInfo.componentNames.Length.should_be(CID.TotalComponents);
            for (int i = 0; i < ctx.contextInfo.componentNames.Length; i++) {
                ctx.contextInfo.componentNames[i].should_be("Index " + i);
            }
        };

        it["creates component pools"] = () => {
            ctx.componentPools.should_not_be_null();
            ctx.componentPools.Length.should_be(CID.TotalComponents);
        };

        it["creates entity with component pools"] = () => {
            var e = ctx.CreateEntity();
            e.componentPools.should_be_same(ctx.componentPools);
        };

        it["throws when destroying an entity which the context doesn't contain"] = expect<ContextDoesNotContainEntityException>(() => {
            var e = ctx.CreateEntity();
            ctx.DestroyEntity(e);
            ctx.DestroyEntity(e);
        });

        it["can ToString"] = () => {
            ctx.ToString().should_be("Unnamed Context");
        };

        context["when ContextInfo set"] = () => {

            ContextInfo contextInfo = null;

            before = () => {
                var componentNames = new [] { "Health", "Position", "View" };
                var componentTypes = new [] { typeof(ComponentA), typeof(ComponentB), typeof(ComponentC) };
                contextInfo = new ContextInfo("My Context", componentNames, componentTypes);
                ctx = new Context(componentNames.Length, 0, contextInfo);
            };

            it["has custom ContextInfo"] = () => {
                ctx.contextInfo.should_be_same(contextInfo);
            };

            it["creates entity with same ContextInfo"] = () => {
                ctx.CreateEntity().contextInfo.should_be_same(contextInfo);
            };

            it["throws when componentNames is not same length as totalComponents"] = expect<ContextInfoException>(() => {
                new Context(contextInfo.componentNames.Length + 1, 0, contextInfo);
            });
        };

        context["when entity created"] = () => {

            Entity e = null;

            before = () => {
                e = ctx.CreateEntity();
                e.AddComponentA();
            };

            it["gets total entity count"] = () => {
                ctx.count.should_be(1);
            };

            it["has entities that were created with CreateEntity()"] = () => {
                ctx.HasEntity(e).should_be_true();
            };

            it["doesn't have entities that were not created with CreateEntity()"] = () => {
                ctx.HasEntity(this.CreateEntity()).should_be_false();
            };

            it["returns all created entities"] = () => {
                var e2 = ctx.CreateEntity();
                var entities = ctx.GetEntities();
                entities.Length.should_be(2);
                entities.should_contain(e);
                entities.should_contain(e2);
            };

            it["destroys entity and removes it"] = () => {
                ctx.DestroyEntity(e);
                ctx.HasEntity(e).should_be_false();
                ctx.count.should_be(0);
                ctx.GetEntities().should_be_empty();
            };

            it["destroys an entity and removes all its components"] = () => {
                ctx.DestroyEntity(e);
                e.GetComponents().should_be_empty();
            };

            it["destroys all entities"] = () => {
                ctx.CreateEntity();
                ctx.DestroyAllEntities();
                ctx.HasEntity(e).should_be_false();
                ctx.count.should_be(0);
                ctx.GetEntities().should_be_empty();
                e.GetComponents().should_be_empty();
            };

            it["ensures same deterministic order when getting entities after destroying all entities"] = () => {

                // This is a Unity specific problem. Run Unity Test Tools with in the Entitas.Unity project

                const int numEntities = 10;

                for (int i = 0; i < numEntities; i++) {
                    ctx.CreateEntity();
                }

                var order1 = new int[numEntities];
                var entities1 = ctx.GetEntities();
                for (int i = 0; i < numEntities; i++) {
                    order1[i] = entities1[i].creationIndex;
                }

                ctx.DestroyAllEntities();
                ctx.ResetCreationIndex();

                for (int i = 0; i < numEntities; i++) {
                    ctx.CreateEntity();
                }

                var order2 = new int[numEntities];
                var entities2 = ctx.GetEntities();
                for (int i = 0; i < numEntities; i++) {
                    order2[i] = entities2[i].creationIndex;
                }

                for (int i = 0; i < numEntities; i++) {
                    var index1 = order1[i];
                    var index2 = order2[i];
                    index1.should_be(index2);
                }
            };

            it["throws when destroying all entities and there are still entities retained"] = expect<ContextStillHasRetainedEntitiesException>(() => {
                ctx.CreateEntity().Retain(new object());
                ctx.DestroyAllEntities();
            });
        };

        context["internal caching"] = () => {

            it["caches entities"] = () => {
                var entities = ctx.GetEntities();
                ctx.GetEntities().should_be_same(entities);
            };

            it["updates entities cache when creating an entity"] = () => {
                var entities = ctx.GetEntities();
                ctx.CreateEntity();
                ctx.GetEntities().should_not_be_same(entities);
            };

            it["updates entities cache when destroying an entity"] = () => {
                var e = ctx.CreateEntity();
                var entities = ctx.GetEntities();
                ctx.DestroyEntity(e);
                ctx.GetEntities().should_not_be_same(entities);
            };
        };

        context["events"] = () => {

            var didDispatch = 0;

            before = () => {
                didDispatch = 0;
            };

            it["dispatches OnEntityCreated when creating a new entity"] = () => {
                Entity eventEntity = null;
                ctx.OnEntityCreated += (p, entity) => {
                    didDispatch += 1;
                    eventEntity = entity;
                    p.should_be_same(p);
                };

                var e = ctx.CreateEntity();
                didDispatch.should_be(1);
                eventEntity.should_be_same(e);
            };

            it["dispatches OnEntityWillBeDestroyed when destroying an entity"] = () => {
                var e = ctx.CreateEntity();
                e.AddComponentA();
                ctx.OnEntityWillBeDestroyed += (p, entity) => {
                    didDispatch += 1;
                    p.should_be_same(ctx);
                    entity.should_be_same(e);
                    entity.HasComponentA().should_be_true();
                    entity.isEnabled.should_be_true();

                    p.GetEntities().Length.should_be(0);
                };
                ctx.GetEntities();
                ctx.DestroyEntity(e);
                didDispatch.should_be(1);
            };

            it["dispatches OnEntityDestroyed when destroying an entity"] = () => {
                var e = ctx.CreateEntity();
                ctx.OnEntityDestroyed += (p, entity) => {
                    didDispatch += 1;
                    p.should_be_same(ctx);
                    entity.should_be_same(e);
                    entity.HasComponentA().should_be_false();
                    entity.isEnabled.should_be_false();
                };
                ctx.DestroyEntity(e);
                didDispatch.should_be(1);
            };

            it["entity is released after OnEntityDestroyed"] = () => {
                var e = ctx.CreateEntity();
                ctx.OnEntityDestroyed += (p, entity) => {
                    didDispatch += 1;
                    entity.retainCount.should_be(1);
                    var newEntity = ctx.CreateEntity();
                    newEntity.should_not_be_null();
                    newEntity.should_not_be_same(entity);
                };
                ctx.DestroyEntity(e);
                var reusedEntity = ctx.CreateEntity();
                reusedEntity.should_be_same(e);
                didDispatch.should_be(1);
            };

            it["throws if entity is released before it is destroyed"] = expect<EntityIsNotDestroyedException>(() => {
                var e = ctx.CreateEntity();
                e.Release(ctx);
            });

            it["dispatches OnGroupCreated when creating a new group"] = () => {
                Group eventGroup = null;
                ctx.OnGroupCreated += (p, g) => {
                    didDispatch += 1;
                    p.should_be_same(ctx);
                    eventGroup = g;
                };
                var group = ctx.GetGroup(Matcher.AllOf(0));
                didDispatch.should_be(1);
                eventGroup.should_be_same(group);
            };

            it["doesn't dispatch OnGroupCreated when group alredy exists"] = () => {
                ctx.GetGroup(Matcher.AllOf(0));
                ctx.OnGroupCreated += delegate { this.Fail(); };
                ctx.GetGroup(Matcher.AllOf(0));
            };

            it["dispatches OnGroupCleared when clearing groups"] = () => {
                Group eventGroup = null;
                ctx.OnGroupCleared += (p, g) => {
                    didDispatch += 1;
                    p.should_be_same(ctx);
                    eventGroup = g;
                };
                ctx.GetGroup(Matcher.AllOf(0));
                var group2 = ctx.GetGroup(Matcher.AllOf(1));
                ctx.ClearGroups();

                didDispatch.should_be(2);
                eventGroup.should_be_same(group2);
            };

            it["removes all external delegates when destroying an entity"] = () => {
                var e = ctx.CreateEntity();
                e.OnComponentAdded += delegate { this.Fail(); };
                e.OnComponentRemoved += delegate { this.Fail(); };
                e.OnComponentReplaced += delegate { this.Fail(); };
                ctx.DestroyEntity(e);
                var e2 = ctx.CreateEntity();
                e2.should_be_same(e);
                e2.AddComponentA();
                e2.ReplaceComponentA(Component.A);
                e2.RemoveComponentA();
            };

            it["will not remove external delegates for OnEntityReleased"] = () => {
                var e = ctx.CreateEntity();
                var didRelease = 0;
                e.OnEntityReleased += entity => didRelease += 1;
                ctx.DestroyEntity(e);
                didRelease.should_be(1);
            };

            it["removes all external delegates from OnEntityReleased when after being dispatched"] = () => {
                var e = ctx.CreateEntity();
                var didRelease = 0;
                e.OnEntityReleased += entity => didRelease += 1;
                ctx.DestroyEntity(e);
                e.Retain(this);
                e.Release(this);
                didRelease.should_be(1);
            };

            it["removes all external delegates from OnEntityReleased after being dispatched (when delayed release)"] = () => {
                var e = ctx.CreateEntity();
                var didRelease = 0;
                e.OnEntityReleased += entity => didRelease += 1;
                e.Retain(this);
                ctx.DestroyEntity(e);
                didRelease.should_be(0);
                e.Release(this);
                didRelease.should_be(1);

                e.Retain(this);
                e.Release(this);
                didRelease.should_be(1);
            };
        };

        context["entity pool"] = () => {

            it["gets entity from object pool"] = () => {
                var e = ctx.CreateEntity();
                e.should_not_be_null();
                e.GetType().should_be(typeof(Entity));
            };

            it["destroys entity when pushing back to object pool"] = () => {
                var e = ctx.CreateEntity();
                e.AddComponentA();
                ctx.DestroyEntity(e);
                e.HasComponent(CID.ComponentA).should_be_false();
            };

            it["returns pushed entity"] = () => {
                var e = ctx.CreateEntity();
                e.AddComponentA();
                ctx.DestroyEntity(e);
                var entity = ctx.CreateEntity();
                entity.HasComponent(CID.ComponentA).should_be_false();
                entity.should_be_same(e);
            };

            it["only returns released entities"] = () => {
                var e1 = ctx.CreateEntity();
                e1.Retain(this);
                ctx.DestroyEntity(e1);
                var e2 = ctx.CreateEntity();
                e2.should_not_be_same(e1);
                e1.Release(this);
                var e3 = ctx.CreateEntity();
                e3.should_be_same(e1);
            };

            it["returns new entity"] = () => {
                var e1 = ctx.CreateEntity();
                e1.AddComponentA();
                ctx.DestroyEntity(e1);
                ctx.CreateEntity();
                var e2 = ctx.CreateEntity();
                e2.HasComponent(CID.ComponentA).should_be_false();
                e2.should_not_be_same(e1);
            };

            it["sets up entity from pool"] = () => {
                ctx.DestroyEntity(ctx.CreateEntity());
                var g = ctx.GetGroup(Matcher.AllOf(CID.ComponentA));
                var e = ctx.CreateEntity();
                e.AddComponentA();
                g.GetEntities().should_contain(e);
            };

            context["when entity gets destroyed"] = () => {

                Entity e = null;

                before = () => {
                    e = ctx.CreateEntity();
                    e.AddComponentA();
                    ctx.DestroyEntity(e);
                };

                it["throws when adding component"] = expect<EntityIsNotEnabledException>(() => e.AddComponentA());
                it["throws when removing component"] = expect<EntityIsNotEnabledException>(() => e.RemoveComponentA());
                it["throws when replacing component"] = expect<EntityIsNotEnabledException>(() => e.ReplaceComponentA(new ComponentA()));
                it["throws when replacing component with null"] = expect<EntityIsNotEnabledException>(() => e.ReplaceComponentA(null));
            };
        };

        context["groups"] = () => {

            it["gets empty group for matcher when no entities were created"] = () => {
                var g = ctx.GetGroup(Matcher.AllOf(CID.ComponentA));
                g.should_not_be_null();
                g.GetEntities().should_be_empty();
            };

            context["when entities created"] = () => {

                Entity eAB1 = null;
                Entity eAB2 = null;
                Entity eA = null;

                IMatcher matcherAB = Matcher.AllOf(new [] {
                    CID.ComponentA,
                    CID.ComponentB
                });

                before = () => {
                    eAB1 = ctx.CreateEntity();
                    eAB1.AddComponentA();
                    eAB1.AddComponentB();

                    eAB2 = ctx.CreateEntity();
                    eAB2.AddComponentA();
                    eAB2.AddComponentB();

                    eA = ctx.CreateEntity();
                    eA.AddComponentA();
                };

                it["gets group with matching entities"] = () => {
                    var g = ctx.GetGroup(matcherAB).GetEntities();
                    g.Length.should_be(2);
                    g.should_contain(eAB1);
                    g.should_contain(eAB2);
                };

                it["gets cached group"] = () => {
                    ctx.GetGroup(matcherAB).should_be_same(ctx.GetGroup(matcherAB));
                };

                it["cached group contains newly created matching entity"] = () => {
                    var g = ctx.GetGroup(matcherAB);
                    eA.AddComponentB();
                    g.GetEntities().should_contain(eA);
                };

                it["cached group doesn't contain entity which are not matching anymore"] = () => {
                    var g = ctx.GetGroup(matcherAB);
                    eAB1.RemoveComponentA();
                    g.GetEntities().should_not_contain(eAB1);
                };

                it["removes destroyed entity"] = () => {
                    var g = ctx.GetGroup(matcherAB);
                    ctx.DestroyEntity(eAB1);
                    g.GetEntities().should_not_contain(eAB1);
                };

                it["group dispatches OnEntityRemoved and OnEntityAdded when replacing components"] = () => {
                    var g = ctx.GetGroup(matcherAB);
                    var didDispatchRemoved = 0;
                    var didDispatchAdded = 0;
                    var componentA = new ComponentA();
                    g.OnEntityRemoved += (group, entity, index, component) => {
                        group.should_be_same(g);
                        entity.should_be_same(eAB1);
                        index.should_be(CID.ComponentA);
                        component.should_be_same(Component.A);
                        didDispatchRemoved++;
                    };
                    g.OnEntityAdded += (group, entity, index, component) => {
                        group.should_be_same(g);
                        entity.should_be_same(eAB1);
                        index.should_be(CID.ComponentA);
                        component.should_be_same(componentA);
                        didDispatchAdded++;
                    };
                    eAB1.ReplaceComponentA(componentA);

                    didDispatchRemoved.should_be(1);
                    didDispatchAdded.should_be(1);
                };

                it["group dispatches OnEntityUpdated with previous and current component when replacing a component"] = () => {
                    var updated = 0;
                    var prevComp = eA.GetComponent(CID.ComponentA);
                    var newComp = new ComponentA();
                    var g = ctx.GetGroup(Matcher.AllOf(CID.ComponentA));
                    g.OnEntityUpdated += (group, entity, index, previousComponent, newComponent) => {
                        updated += 1;
                        group.should_be_same(g);
                        entity.should_be_same(eA);
                        index.should_be(CID.ComponentA);
                        previousComponent.should_be_same(prevComp);
                        newComponent.should_be_same(newComp);
                    };

                    eA.ReplaceComponent(CID.ComponentA, newComp);

                    updated.should_be(1);
                };

                it["group with matcher NoneOf doesn't dispatch OnEntityAdded when destroying entity"] = () => {
                    var e = ctx.CreateEntity()
                                .AddComponentA()
                                .AddComponentB();
                    var matcher = Matcher.AllOf(CID.ComponentB).NoneOf(CID.ComponentA);
                    var g = ctx.GetGroup(matcher);
                    g.OnEntityAdded += delegate { this.Fail(); };
                    ctx.DestroyEntity(e);
                };

                context["event timing"] = () => {

                    before = () => {
                        ctx = new Context(CID.TotalComponents);
                    };

                    it["dispatches group.OnEntityAdded events after all groups are updated"] = () => {
                        var groupA = ctx.GetGroup(Matcher.AllOf(CID.ComponentA, CID.ComponentB));
                        var groupB = ctx.GetGroup(Matcher.AllOf(CID.ComponentB));

                        groupA.OnEntityAdded += delegate {
                            groupB.count.should_be(1);
                        };

                        var entity = ctx.CreateEntity();
                        entity.AddComponentA();
                        entity.AddComponentB();
                    };

                    it["dispatches group.OnEntityRemoved events after all groups are updated"] = () => {
                        ctx = new Context(CID.TotalComponents);
                        var groupB = ctx.GetGroup(Matcher.AllOf(CID.ComponentB));
                        var groupAB = ctx.GetGroup(Matcher.AllOf(CID.ComponentA, CID.ComponentB));

                        groupB.OnEntityRemoved += delegate {
                            groupAB.count.should_be(0);
                        };

                        var entity = ctx.CreateEntity();
                        entity.AddComponentA();
                        entity.AddComponentB();

                        entity.RemoveComponentB();
                    };
                };
            };
        };

        context["EntityIndex"] = () => {

            it["throws when EntityIndex for key doesn't exist"] = expect<ContextEntityIndexDoesNotExistException>(() => {
                ctx.GetEntityIndex("unknown");
            });

            it["adds and EntityIndex"] = () => {
                const int componentIndex = 1;
                var entityIndex = new PrimaryEntityIndex<string>(ctx.GetGroup(Matcher.AllOf(componentIndex)), null);
                ctx.AddEntityIndex(componentIndex.ToString(), entityIndex);
                ctx.GetEntityIndex(componentIndex.ToString()).should_be_same(entityIndex);
            };

            it["throws when adding an EntityIndex with same name"] = expect<ContextEntityIndexDoesAlreadyExistException>(() => {
                const int componentIndex = 1;
                var entityIndex = new PrimaryEntityIndex<string>(ctx.GetGroup(Matcher.AllOf(componentIndex)), null);
                ctx.AddEntityIndex(componentIndex.ToString(), entityIndex);
                ctx.AddEntityIndex(componentIndex.ToString(), entityIndex);
            });
        };

        context["reset"] = () => {

            context["groups"] = () => {

                it["resets and removes groups from context"] = () => {

                    var m = Matcher.AllOf(CID.ComponentA);
                    var groupsCreated = 0;
                    Group createdGroup = null;
                    ctx.OnGroupCreated += (p, g) => {
                        groupsCreated += 1;
                        createdGroup = g;
                    };

                    var initialGroup = ctx.GetGroup(m);

                    ctx.ClearGroups();

                    ctx.GetGroup(m);

                    ctx.CreateEntity().AddComponentA();

                    groupsCreated.should_be(2);
                    createdGroup.should_not_be_same(initialGroup);

                    initialGroup.count.should_be(0);
                    createdGroup.count.should_be(1);
                };

                it["removes all event handlers from groups"] = () => {
                    var m = Matcher.AllOf(CID.ComponentA);
                    var group = ctx.GetGroup(m);

                    group.OnEntityAdded += delegate { this.Fail(); };

                    ctx.ClearGroups();

                    var e = ctx.CreateEntity();
                    e.AddComponentA();
                    group.HandleEntity(e, CID.ComponentA, Component.A);
                };

                it["releases entities in groups"] = () => {
                    var m = Matcher.AllOf(CID.ComponentA);
                    ctx.GetGroup(m);
                    var entity = ctx.CreateEntity();
                    entity.AddComponentA();

                    ctx.ClearGroups();

                    entity.retainCount.should_be(1);
                };
            };

            context["context"] = () => {

                it["resets creation index"] = () => {
                    ctx.CreateEntity();

                    ctx.ResetCreationIndex();

                    ctx.CreateEntity().creationIndex.should_be(0);
                };

                context["removes all event handlers"] = () => {

                    it["removes OnEntityCreated"] = () => {
                        ctx.OnEntityCreated += delegate { this.Fail(); };
                        ctx.Reset();

                        ctx.CreateEntity();
                    };

                    it["removes OnEntityWillBeDestroyed"] = () => {
                        ctx.OnEntityWillBeDestroyed += delegate { this.Fail(); };
                        ctx.Reset();

                        ctx.DestroyEntity(ctx.CreateEntity());
                    };

                    it["removes OnEntityDestroyed"] = () => {
                        ctx.OnEntityDestroyed += delegate { this.Fail(); };
                        ctx.Reset();

                        ctx.DestroyEntity(ctx.CreateEntity());
                    };

                    it["removes OnGroupCreated"] = () => {
                        ctx.OnGroupCreated += delegate { this.Fail(); };
                        ctx.Reset();

                        ctx.GetGroup(Matcher.AllOf(0));
                    };

                    it["removes OnGroupCleared"] = () => {
                        ctx.OnGroupCleared += delegate { this.Fail(); };
                        ctx.Reset();
                        ctx.GetGroup(Matcher.AllOf(0));

                        ctx.ClearGroups();
                    };
                };
            };

            context["component pools"] = () => {

                before = () => {
                    var entity = ctx.CreateEntity();
                    entity.AddComponentA();
                    entity.AddComponentB();
                    entity.RemoveComponentA();
                    entity.RemoveComponentB();
                };

                it["clears all component pools"] = () => {
                    ctx.componentPools[CID.ComponentA].Count.should_be(1);
                    ctx.componentPools[CID.ComponentB].Count.should_be(1);

                    ctx.ClearComponentPools();

                    ctx.componentPools[CID.ComponentA].Count.should_be(0);
                    ctx.componentPools[CID.ComponentB].Count.should_be(0);
                };

                it["clears a specific component pool"] = () => {
                    ctx.ClearComponentPool(CID.ComponentB);

                    ctx.componentPools[CID.ComponentA].Count.should_be(1);
                    ctx.componentPools[CID.ComponentB].Count.should_be(0);
                };

                it["only clears existing component pool"] = () => {
                    ctx.ClearComponentPool(CID.ComponentC);
                };
            };

            context["EntityIndex"] = () => {

                PrimaryEntityIndex<string> entityIndex = null;

                before = () => {
                    entityIndex = new PrimaryEntityIndex<string>(ctx.GetGroup(Matcher.AllOf(CID.ComponentA)),
                        (e, c) => ((NameAgeComponent)(c)).name);
                    ctx.AddEntityIndex(CID.ComponentA.ToString(), entityIndex);
                };

                it["deactivates EntityIndex"] = () => {
                    var nameAgeComponent = new NameAgeComponent();
                    nameAgeComponent.name = "Max";

                    ctx.CreateEntity().AddComponent(CID.ComponentA, nameAgeComponent);
                    entityIndex.HasEntity("Max").should_be_true();

                    ctx.DeactivateAndRemoveEntityIndices();

                    entityIndex.HasEntity("Max").should_be_false();
                };

                it["removes EntityIndex"] = expect<ContextEntityIndexDoesNotExistException>(() => {
                    ctx.DeactivateAndRemoveEntityIndices();
                    ctx.GetEntityIndex(CID.ComponentA.ToString());
                });
            };
        };

        context["EntitasCache"] = () => {

            it["pops new list from list pool"] = () => {
                var groupA = ctx.GetGroup(Matcher.AllOf(CID.ComponentA));
                var groupAB = ctx.GetGroup(Matcher.AnyOf(CID.ComponentA, CID.ComponentB));
                var groupABC = ctx.GetGroup(Matcher.AnyOf(CID.ComponentA, CID.ComponentB, CID.ComponentC));

                var didExecute = 0;

                groupA.OnEntityAdded += (g, entity, index, component) => {
                    didExecute += 1;
                    entity.RemoveComponentA();
                };

                groupAB.OnEntityAdded += (g, entity, index, component) => {
                    didExecute += 1;
                };

                groupABC.OnEntityAdded += (g, entity, index, component) => {
                    didExecute += 1;
                };

                ctx.CreateEntity().AddComponentA();

                didExecute.should_be(3);
            };
        };
    }