public void IndexOfSpanTest() { Span span1 = new Span() { Text = "This is sample text." }; Span span2 = new Span() { Text = "This is text." }; Span span3 = new Span() { Text = "That is text." }; Assert.AreEqual(text.IndexOfSpan(span1), 0); Assert.AreEqual(text.IndexOfSpan(span2), 4); Assert.AreEqual(text.IndexOfSpan(span1, 1), -1); Assert.AreEqual(text.IndexOfSpan(span2, 0, 1), -1); Assert.AreEqual(text.IndexOfSpan(span3), -1); }