private static TokenType ReadLiteral(CharReader reader)
{
while (!reader.IsAtEnd)
{
switch (reader.Current)
{
case '{':
if (reader.Next == '{')
{
reader.MoveNext();
reader.MoveNext();
continue;
}
return(TokenType.CaptureName);
case '}':
if (reader.Next == '}')
{
reader.MoveNext();
reader.MoveNext();
continue;
}
else
{
throw new FormatException($"At index {reader.Position}, there is an unescaped '}}' character.");
}
}
reader.MoveNext();
}
return(TokenType.Literal);
}
private static TokenType ReadCaptureName(CharReader reader)
{
var startPosition = reader.Position;
reader.MoveNext();
while (!reader.IsAtEnd)
{
switch (reader.Current)
{
case '{':
throw new FormatException($"At index {reader.Position}, there is an unexpected '{{' character.");
case '}':
reader.MoveNext();
return(TokenType.Literal);
}
reader.MoveNext();
}
throw new FormatException($"There is a capture section starting at index {startPosition} without a terminating '}}' character.");
}
private static void TestCursorPosition(string text, CursorPosition position)
{
var reader = new CharReader(new StringReader(text));
for (int i = 0; i < text.Length; i++)
{
reader.MoveNext();
}
string msg = $"'{text.Replace("\r", "\\r").Replace("\n", "\\n")}': current ";
Assert.AreEqual(position.Row, reader.CurrentRow, msg + "row");
Assert.AreEqual(position.Column, reader.CurrentColumn, msg + "column");
Assert.AreEqual(text.Length, reader.CurrentIndex, msg + "index");
}