public void Assign_Controls()
        {
            var content = Substitute.For<Control>();
            var navigation = Substitute.For<IHaveNavigation, Control>();

            var control = new ContentFrame(content, navigation);

            control.Content.Content.Should().Be(content);
            control.Navigation.Content.Should().Be(navigation);
        }
        public void Be_Creatable()
        {
            var control = new ContentFrame();

            control.Should().BeAssignableTo<IHaveFrame>();
        }