public void Test_Equals()
{
var rectangle = new Rectangle(1, 2, 3, 4);
var equalRectange = new Rectangle(1, 2, 3, 4);
var unequalRectangle = new Rectangle(2, 3, 4, 5);
Assert.AreEqual(rectangle, equalRectange);
Assert.AreNotEqual(rectangle, unequalRectangle);
Assert.AreNotEqual(rectangle, null);
Assert.AreNotEqual(rectangle, new object());
}