public void TestTurnMove()
{
Turtle t = new Turtle();
t.Left(45);
t.Forward(10);
Assert.AreEqual(7.07, t.X, 0.002);
Assert.AreEqual(7.07, t.Y, 0.002);
t.Undo();
t.Left(45);
t.Forward(10);
Assert.AreEqual(0, t.X, 0.002);
Assert.AreEqual(10, t.Y);
t.Undo();
t.Left(45);
t.Forward(10);
Assert.AreEqual(-7.07, t.X, 0.002);
Assert.AreEqual(7.07, t.Y, 0.002);
}