public void TestPosition()
        {
            // setup
            FadeIn fade = new FadeIn();

            // when
            fade.Position = Position.CenterMiddle;

            // then
            Assert.AreEqual(Position.CenterMiddle, fade.Position);
        }
        public void TestGetCurrentValue()
        {
            // setup
            FadeIn fade = new FadeIn();

            fade.Position              = Position.CenterTop;
            MainWindow.Current         = new MainWindow();
            MainWindow.Current.Opacity = 0.0;

            // when
            Assert.AreEqual(0.0, fade.GetCurrentValue(null, null, 0.0));
            Assert.AreEqual(0.5, fade.GetCurrentValue(null, null, 0.5));
            Assert.AreEqual(1.0, fade.GetCurrentValue(null, null, 1.0));
            Assert.AreEqual(Position.CenterTop,
                            WindowOperator.GetInstance().GetValue(WindowOperator.PositionProperty));
        }