public static NextTokenType PeekNextToken(HtmlCharStream cs, int tagEnd, out ITextRange range) {
NextTokenType tokenType = NextTokenType.Unknown;
int current = cs.Position;
if (cs.IsEndOfStream() || cs.Position == tagEnd) {
range = new TextRange();
return NextTokenType.None;
}
int start = cs.Position;
while (cs.IsWhiteSpace())
cs.MoveToNextChar();
if (cs.IsEndOfStream() || cs.Position == tagEnd) {
range = TextRange.FromBounds(start, cs.Position);
return NextTokenType.Unknown;
}
if (cs.IsAtTagDelimiter()) {
tokenType = NextTokenType.Tag;
} else if (cs.CurrentChar == '=') {
tokenType = NextTokenType.Equals;
} else {
int digits = 0;
bool firstLetter = false;
int length = 0;
int chars = 0;
if (cs.IsAnsiLetter())
firstLetter = true;
while (!cs.IsEndOfStream() && !cs.IsWhiteSpace() && !cs.IsAtTagDelimiter() && cs.CurrentChar != '=' && cs.Position < tagEnd) {
if (cs.IsAnsiLetter() || cs.CurrentChar == '_' || cs.CurrentChar == '-')
chars++;
else if (cs.IsDecimal() || cs.CurrentChar == '.')
digits++;
cs.MoveToNextChar();
length++;
}
if (length > 0) {
if (length == digits)
tokenType = NextTokenType.Number;
else if (length == chars)
tokenType = NextTokenType.Letters;
else if (firstLetter)
tokenType = NextTokenType.Identifier;
}
}
range = TextRange.FromBounds(start, cs.Position);
cs.Position = current;
return tokenType;
}
public void HtmlCharStream_IsNameCharTest() {
var stream = new HtmlCharStream(new TextStream(""));
Assert.True(stream.IsEndOfStream());
Assert.Equal(0, stream.Length);
stream = new HtmlCharStream(new TextStream("<h123"));
Assert.Equal(0, stream.Position);
Assert.False(stream.IsEndOfStream());
stream.Position = 5;
Assert.True(stream.IsEndOfStream());
stream.Position = 0;
Assert.False(stream.IsEndOfStream());
stream.MoveToNextChar();
Assert.Equal(1, stream.Position);
stream.Advance(2);
Assert.Equal(3, stream.Position);
stream.Advance(-2);
Assert.Equal(1, stream.Position);
stream.Advance(1000);
Assert.True(stream.IsEndOfStream());
stream.Position = 0;
Assert.True(stream.IsAtTagDelimiter());
Assert.Equal('<', stream.CurrentChar);
Assert.Equal('h', stream.NextChar);
stream.Position = 1;
Assert.False(stream.IsAtTagDelimiter());
Assert.True(stream.IsNameChar());
Assert.True(HtmlCharStream.IsNameStartChar(stream.CurrentChar));
stream.Position = 2;
Assert.False(stream.IsAtTagDelimiter());
Assert.True(stream.IsNameChar());
Assert.False(HtmlCharStream.IsNameStartChar(stream.CurrentChar));
}
public void CharStream_BasicTest() {
string text = "abcd\"foo\"\r\n<a href=";
HtmlCharStream cs = new HtmlCharStream(text);
Assert.Equal('a', cs.CurrentChar);
cs.Advance(2);
Assert.False(cs.IsEndOfStream());
Assert.Equal('c', cs.CurrentChar);
cs.Advance(-1);
Assert.False(cs.IsEndOfStream());
Assert.Equal('b', cs.CurrentChar);
cs.Advance(text.Length);
Assert.True(cs.IsEndOfStream());
Assert.Equal(0, cs.CurrentChar);
cs.Advance(-text.Length);
Assert.False(cs.IsEndOfStream());
Assert.Equal('a', cs.CurrentChar);
Assert.Equal('d', cs.LookAhead(3));
Assert.Equal('\"', cs.LookAhead(4));
Assert.Equal(0, cs.LookAhead(text.Length));
Assert.Equal(0, cs.LookAhead(-1));
Assert.Equal(text.Length, cs.DistanceFromEnd);
cs.Advance(1);
Assert.Equal(text.Length - 1, cs.DistanceFromEnd);
cs.Position = 4;
Assert.True(cs.IsAtString());
cs.Position = 5;
Assert.False(cs.IsAtString());
cs.Position = 9;
Assert.True(cs.IsWhiteSpace());
cs.MoveToNextChar();
Assert.True(cs.IsWhiteSpace());
cs.MoveToNextChar();
Assert.True(cs.IsAtTagDelimiter());
}
