public void SubstringWithLengthTest()
{
const string originalString = "asdf werljk xov .qw 120 xcv;z";
var s = new StyledText(originalString, Color.Black);
var s2 = s.Substring(5, 4);
Assert.AreEqual(s.Text, originalString);
Assert.AreEqual(Color.Black, s.Color);
Assert.AreEqual(originalString.Substring(5, 4), s2.Text);
Assert.AreEqual(Color.Black, s2.Color);
}