public void TestSelectFragmentMoveUp()
 {
     textCore.SetCursorPosition(1, 3);
     Assert.AreEqual(4, textCore.VisualOffset);
     textCore.SelectFragment(1, 3);
     Assert.AreEqual(9, textCore.VisualOffset);
     textCore.DoNavigation(System.Windows.Input.Key.Up);
     Assert.AreEqual(9, textCore.VisualOffset);
     Assert.AreEqual(3, textCore.CursorPosition.X);
     Assert.AreEqual(2, textCore.CursorPosition.Y);
 }
 public void TestSelectFragmentDouble()
 {
     // Double-clicking between "6" and "7" within "4.5678".
     textCore.SelectFragment(16, 7);
     Assert.AreEqual(textCore.SelectionText, "4.5678");
     Assert.AreEqual(textCore.CursorPosition.X, 19);
     Assert.AreEqual(textCore.CursorPosition.Y, 7);
 }