/// <summary>
/// Creates a new scan token.
/// </summary>
/// <param name="type">Type of characters found.</param>
/// <param name="text">Characters found.</param>
/// <param name="start">Position of the first character found.</param>
/// <exception cref="ArgumentException">text was empty or null; type was <see cref="Mark"/> but text was more than one character; type was not understood.</exception>
public ScanToken(ScanTokenType type, string text, ScanPosition start)
{
Text = NotNullOrEmpty(text, nameof(text));
Type = type;
Start = start;
switch (type)
{
case ScanTokenType.Mark:
if (text.Length > 1)
{
throw new ArgumentException("Mark tokens must be a single character", nameof(text));
}
End = start;
break;
case ScanTokenType.Word:
case ScanTokenType.Space:
End = start + (uint)text.Length;
break;
case ScanTokenType.Newline:
End = new ScanPosition(start.Absolute + (uint)text.Length, start.Row + 1, 0);
break;
default:
throw new ArgumentException($"{type} is not a supported scan token type", nameof(type));
}
}
public void New_WithBadParameters_Throws(ScanTokenType type, string text, string badParameterName)
{
TestAction(() => new ScanToken(type, text, Start))
.Should().Throw <ArgumentException>()
.Where(x => x.ParamName == badParameterName);
}
