public void ToStringMethodWorksCorrectly() { var displayText = new DisplayText(); //return empty string if it contains nothing Assert.Equal("", displayText.ToString()); //returns single line if it has only one line var value = "Hello World!"; displayText.Add(value); Assert.Equal(value, displayText.ToString()); //returns multiple lines seperated by '/r/n' if it has multiple lines displayText.Add(value); Assert.Equal(value + "/r/n" + value, displayText.ToString()); }