feat(ComponentMapper): Add 'TryGet' methods (#1006)

* feat(ComponentMapper): Add 'TryGet' methods

* feat(tests): Add test for new 'TryGet' method in 'ComponentMapper'

* refact(ComponentMapper): Simplify logic in 'TryGet' method

source/MonoGame.Extended/ECS/ComponentMapper.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Diagnostics.CodeAnalysis;
 using MonoGame.Extended.Collections;
 
 namespace MonoGame.Extended.ECS
@@ -51,6 +52,17 @@ namespace MonoGame.Extended.ECS
             return Components[entityId];
         }
 
+        public bool TryGet(Entity entity, [NotNullWhen(true)] out T result)
+        {
+            return TryGet(entity.Id, out result);
+        }
+
+        public bool TryGet(int entityId, [NotNullWhen(true)] out T result)
+        {
+            result = Get(entityId);
+            return result != null;
+        }
+
         public override bool Has(int entityId)
         {
             if (entityId >= Components.Count)

tests/MonoGame.Extended.Tests/ECS/ComponentMapperTests.cs

@@ -45,6 +45,31 @@ namespace MonoGame.Extended.ECS.Tests
             Assert.Same(component, mapper.Get(entityId));
         }
 
+        [Fact]
+        public void PutAndTryGetComponent()
+        {
+            // Arrange
+            const int entityId = 4;
+            const int entityIdNotAdded = 100;
+
+            var mapper = new ComponentMapper<Transform2>(1, _ => { });
+            var component = new Transform2();
+
+            mapper.Put(entityId, component);
+
+            // Act
+            bool foundAdded = mapper.TryGet(entityId, out Transform2 transformFromAdded);
+            bool foundNotAdded = mapper.TryGet(entityIdNotAdded, out Transform2 transformFromNotAdded);
+
+            // Assert
+            Assert.Equal(typeof(Transform2), mapper.ComponentType);
+            Assert.True(mapper.Components.Count >= 1);
+            Assert.True(foundAdded);
+            Assert.Same(component, transformFromAdded);
+            Assert.False(foundNotAdded);
+            Assert.Equal(default(Transform2), transformFromNotAdded);
+        }
+
         [Fact]
         public void OnDelete()
         {