public override bool Parse(ItemFactory itemFactory, ITextProvider text, TokenStream tokens)
{
bool hasSubject = false;
// Allow a bang before the tag name.
while (tokens.CurrentToken.TokenType == CssTokenType.Bang)
{
ParseItem item = itemFactory.Create <SubjectSelector>(this);
if (item.Parse(itemFactory, text, tokens))
{
Children.Add(item);
if (hasSubject)
{
item.AddParseError(ParseErrorType.UnexpectedBangInSelector, ParseErrorLocation.WholeItem);
}
hasSubject = true;
}
if (tokens.IsWhiteSpaceBeforeCurrentToken())
{
break;
}
}
if (ItemName.IsAtItemName(tokens))
{
ItemName name = itemFactory.CreateSpecific <ItemName>(this);
if (name.Parse(itemFactory, text, tokens))
{
name.Context = CssClassifierContextCache.FromTypeEnum(CssClassifierContextType.ElementTagName);
Name = name;
Children.Add(name);
}
}
ParseItem lastItem = (Children.Count > 0) ? Children[Children.Count - 1] : null;
// Only continue parsing the simple selector if the name touches the next token.
if (lastItem == null || lastItem.AfterEnd == tokens.CurrentToken.Start)
{
bool addedErrorItem = false;
while (!IsAtSelectorTerminator(tokens))
{
ParseItem pi = CreateNextAtomicPart(itemFactory, text, tokens);
if (pi == null)
{
// Only treat the first bad token as an error (don't need more than one in a row)
if (addedErrorItem)
{
pi = UnknownItem.ParseUnknown(this, itemFactory, text, tokens);
}
else
{
pi = UnknownItem.ParseUnknown(this, itemFactory, text, tokens, ParseErrorType.SimpleSelectorExpected);
addedErrorItem = true;
}
}
else if (!pi.Parse(itemFactory, text, tokens))
{
break;
}
if (pi is SubjectSelector)
{
if (hasSubject)
{
pi.AddParseError(ParseErrorType.UnexpectedBangInSelector, ParseErrorLocation.WholeItem);
}
hasSubject = true;
}
SubSelectors.Add(pi);
Children.Add(pi);
if (tokens.IsWhiteSpaceBeforeCurrentToken())
{
break;
}
}
}
if (IsAtSelectorCombineOperator(text, tokens))
{
ParseSelectorCombineOperator(itemFactory, text, tokens);
if (Name == null &&
SelectorCombineOperator != null &
SubSelectors.Count == 0 &&
!CanStartWithCombineOperator(SelectorCombineOperator))
{
SelectorCombineOperator.AddParseError(ParseErrorType.SelectorBeforeCombineOperatorMissing, ParseErrorLocation.BeforeItem);
}
}
return(Children.Count > 0);
}