public void GetExistingSerializer_Test()
        {
            var serializerMock = new DelegatingObjectSerializer((x, c) => { });
            var factoryMock    = new Mock <ISerializerFactory>();

            factoryMock
            .Setup(f => f.Create(It.IsAny <Type>(), It.IsAny <ISerializationContext>()))
            .Returns(serializerMock);

            var collection  = new SerializerCollection(factoryMock.Object);
            var serializer1 = collection.Get(typeof(SerializerCollectionTests), Mock.Of <ISerializationContext>());
            var serializer2 = collection.Get(typeof(SerializerCollectionTests), Mock.Of <ISerializationContext>());

            Assert.IsNotNull(serializer1);
            Assert.IsNotNull(serializer2);
            Assert.AreSame(serializer1, serializer2);
        }