public void CanMatchLeadingCharactersByPredicate()
{
Predicate<char> letters = Char.IsLetter;
Predicate<char> digits = Char.IsDigit;
Predicate<char> alphanumerics = Char.IsLetterOrDigit;
var empty = new Text("");
empty.Match(letters).ShouldFail();
var abc123 = new Text("abc123");
abc123.Match(digits).ShouldFail();
abc123.Match(letters).ShouldSucceed("abc");
abc123.Match(alphanumerics).ShouldSucceed("abc123");
abc123.Advance(2).Match(digits).ShouldFail();
abc123.Advance(2).Match(letters).ShouldSucceed("c");
abc123.Advance(2).Match(alphanumerics).ShouldSucceed("c123");
abc123.Advance(3).Match(digits).ShouldSucceed("123");
abc123.Advance(3).Match(letters).ShouldFail();
abc123.Advance(3).Match(alphanumerics).ShouldSucceed("123");
abc123.Advance(6).Match(digits).ShouldFail();
abc123.Advance(6).Match(letters).ShouldFail();
abc123.Advance(6).Match(alphanumerics).ShouldFail();
}
public IEnumerable<Token> Tokenize(string input)
{
var text = new Text(input);
while (!text.EndOfInput)
{
var current = GetToken(text);
//After exiting this loop, Current will be the
//next unskippable token, and text will indicate
//where that token starts.
while (current.Kind.Skippable)
{
text = text.Advance(current.Literal.Length);
if (text.EndOfInput)
yield break;
current = GetToken(text);
}
text = text.Advance(current.Literal.Length);
yield return current;
}
}
public void CanGetCurrentPosition()
{
var empty = new Text("");
empty.Advance(0).Position.ShouldEqual(new Position(1, 1));
empty.Advance(1).Position.ShouldEqual(new Position(1, 1));
var lines = new StringBuilder()
.AppendLine("Line 1")//Index 0-5, \n
.AppendLine("Line 2")//Index 7-12, \n
.AppendLine("Line 3");//Index 14-19, \n
var list = new Text(lines.ToString());
list.Advance(0).Position.ShouldEqual(new Position(1, 1));
list.Advance(5).Position.ShouldEqual(new Position(1, 6));
list.Advance(6).Position.ShouldEqual(new Position(1, 7));
list.Advance(7).Position.ShouldEqual(new Position(2, 1));
list.Advance(12).Position.ShouldEqual(new Position(2, 6));
list.Advance(13).Position.ShouldEqual(new Position(2, 7));
list.Advance(14).Position.ShouldEqual(new Position(3, 1));
list.Advance(19).Position.ShouldEqual(new Position(3, 6));
list.Advance(20).Position.ShouldEqual(new Position(3, 7));
list.Advance(21).Position.ShouldEqual(new Position(4, 1));
list.Advance(1000).Position.ShouldEqual(new Position(4, 1));
}
protected override MatchResult Match(Text text)
{
var peek = text.Peek(symbol.Length);
if (peek == symbol)
return MatchResult.Succeed(peek);
return MatchResult.Fail;
}
private Token GetToken(Text text)
{
Token token;
foreach (var kind in kinds)
if (kind.TryMatch(text, out token))
return token;
return null; //Unknown guarantees this is reachable only at the end of input.
}
public void CanAdvanceAheadNCharacters()
{
var empty = new Text("");
empty.Advance(0).ToString().ShouldEqual("");
empty.Advance(1).ToString().ShouldEqual("");
var abc = new Text("abc");
abc.Advance(0).ToString().ShouldEqual("abc");
abc.Advance(1).ToString().ShouldEqual("bc");
abc.Advance(2).ToString().ShouldEqual("c");
abc.Advance(3).ToString().ShouldEqual("");
abc.Advance(4).ToString().ShouldEqual("");
abc.Advance(100).ToString().ShouldEqual("");
}
protected override MatchResult Match(Text text)
{
return text.Match(regex);
}
protected override MatchResult Match(Text text)
{
return MatchResult.Fail;
}
protected abstract MatchResult Match(Text text);
public bool TryMatch(Text text, out Token token)
{
var match = Match(text);
if (match.Success)
{
token = new Token(this, text.Position, match.Value);
return true;
}
token = null;
return false;
}
public TokenKindTests()
{
lower = new Pattern("Lowercase", @"[a-z]+");
upper = new Pattern("Uppercase", @"[A-Z]+");
abcDEF = new Text("abcDEF");
}
public void CanMatchLeadingCharactersByTokenRegex()
{
var end = new TokenRegex(@"$");
var letters = new TokenRegex(@"[a-z]+");
var digits = new TokenRegex(@"[0-9]+");
var alphanumerics = new TokenRegex(@"[a-z0-9]+");
var empty = new Text("");
empty.Match(letters).ShouldFail();
empty.Match(end).ShouldSucceed("");
var abc123 = new Text("abc123");
abc123.Match(digits).ShouldFail();
abc123.Match(letters).ShouldSucceed("abc");
abc123.Match(alphanumerics).ShouldSucceed("abc123");
abc123.Advance(2).Match(digits).ShouldFail();
abc123.Advance(2).Match(letters).ShouldSucceed("c");
abc123.Advance(2).Match(alphanumerics).ShouldSucceed("c123");
abc123.Advance(3).Match(digits).ShouldSucceed("123");
abc123.Advance(3).Match(letters).ShouldFail();
abc123.Advance(3).Match(alphanumerics).ShouldSucceed("123");
abc123.Advance(6).Match(digits).ShouldFail();
abc123.Advance(6).Match(letters).ShouldFail();
abc123.Advance(6).Match(alphanumerics).ShouldFail();
}
public void NormalizesLineEndingsToSingleLineFeedCharacter()
{
var multiline = new Text("Line 1\rLine 2\nLine 3\r\nLine 4");
multiline.ToString().ShouldEqual("Line 1\nLine 2\nLine 3\nLine 4");
}
public void CanPeekAheadNCharacters()
{
var empty = new Text("");
empty.Peek(0).ShouldEqual("");
empty.Peek(1).ShouldEqual("");
var abc = new Text("abc");
abc.Peek(0).ShouldEqual("");
abc.Peek(1).ShouldEqual("a");
abc.Peek(2).ShouldEqual("ab");
abc.Peek(3).ShouldEqual("abc");
abc.Peek(4).ShouldEqual("abc");
abc.Peek(100).ShouldEqual("abc");
}
