public void InsertSpanTest()
{
string s = " That is text.";
Span span = new Span()
{
Text = s
};
var newText = text.InsertSpan(1, span);
Assert.AreEqual(newText[1].Equals(span), true);
Assert.AreEqual(newText.Length, text.Length + 1);
Assert.AreEqual(text.AnySpanReferenceEquals(newText), false);
}
