public void ToViewModel_ShouldReturnCorrectValue(
            [Frozen]Mock<IObservableViewModel> viewModel
            )
        {
            //arrange
			viewModel.As<IObservableViewModel<object>>();
	        var sut = new ExistingObservableViewModelBuilderOptions<object>(viewModel.Object);

            //act
            var actual = sut.ToViewModel();

            //assert
            actual.Should().Be(viewModel.Object);
        }
        public void ToViewModel_ShouldReturnCorrectValue(
            [Frozen] Mock <IObservableViewModel> viewModel
            )
        {
            //arrange
            viewModel.As <IObservableViewModel <object> >();
            var sut = new ExistingObservableViewModelBuilderOptions <object>(viewModel.Object);

            //act
            var actual = sut.ToViewModel();

            //assert
            actual.Should().Be(viewModel.Object);
        }