use super::Parser;
use crate::{
Parse,
ast::*,
bump,
error::{Error, ErrorKind, PResult},
expect, peek,
pos::Span,
tokenizer::{Token, TokenWithSpan},
};
impl<'a> Parse<'a> for ScopeEnd<'a> {
fn parse(input: &mut Parser<'a>) -> PResult<Self> {
let to_span = match bump!(input) {
TokenWithSpan { token: Token::Ident(ident), span }
if ident.name().eq_ignore_ascii_case("to") =>
{
span
}
TokenWithSpan { span, .. } => {
return Err(Error { kind: ErrorKind::ExpectScopeTo, span });
}
};
let (_, lparen_span) = expect!(input, LParen);
let selector = input.parse()?;
let (_, Span { end, .. }) = expect!(input, RParen);
let span = Span { start: to_span.start, end };
Ok(ScopeEnd { to_span, lparen_span, selector, span })
}
}
impl<'a> Parse<'a> for ScopePrelude<'a> {
fn parse(input: &mut Parser<'a>) -> PResult<Self> {
let start = if let Token::LParen(..) = peek!(input).token {
Some(input.parse::<ScopeStart>()?)
} else {
None
};
let end = match &peek!(input).token {
Token::Ident(ident) if ident.name().eq_ignore_ascii_case("to") => {
Some(input.parse::<ScopeEnd>()?)
}
_ => None,
};
match (start, end) {
(Some(start), Some(end)) => {
let span = Span { start: start.span.start, end: end.span.end };
Ok(ScopePrelude::Both(ScopeStartWithEnd { start, end, span }))
}
(Some(start), None) => Ok(ScopePrelude::StartOnly(start)),
(None, Some(end)) => Ok(ScopePrelude::EndOnly(end)),
(None, None) => {
use crate::{token::LParen, tokenizer::TokenSymbol};
let TokenWithSpan { token, span } = bump!(input);
Err(Error { kind: ErrorKind::Unexpected(LParen::symbol(), token.symbol()), span })
}
}
}
}
impl<'a> Parse<'a> for ScopeStart<'a> {
fn parse(input: &mut Parser<'a>) -> PResult<Self> {
let (_, Span { start, .. }) = expect!(input, LParen);
let selector = input.parse()?;
let (_, Span { end, .. }) = expect!(input, RParen);
Ok(ScopeStart { selector, span: Span { start, end } })
}
}