bendns' repos / rust-analyzer
Unnamed repository; edit this file 'description' to name the repository.
Diffstat (limited to 'crates/mbe/src/parser.rs')
-rw-r--r--crates/mbe/src/parser.rs70
1 files changed, 51 insertions, 19 deletions
diff --git a/crates/mbe/src/parser.rs b/crates/mbe/src/parser.rs
index 00ba35377a..afdbbef231 100644
--- a/crates/mbe/src/parser.rs
+++ b/crates/mbe/src/parser.rs
@@ -25,23 +25,26 @@ pub(crate) struct MetaTemplate<S>(pub(crate) Box<[Op<S>]>);
impl<S: Span> MetaTemplate<S> {
pub(crate) fn parse_pattern(pattern: &tt::Subtree<S>) -> Result<Self, ParseError> {
- MetaTemplate::parse(pattern, Mode::Pattern)
+ MetaTemplate::parse(pattern, Mode::Pattern, false)
}
- pub(crate) fn parse_template(template: &tt::Subtree<S>) -> Result<Self, ParseError> {
- MetaTemplate::parse(template, Mode::Template)
+ pub(crate) fn parse_template(
+ template: &tt::Subtree<S>,
+ new_meta_vars: bool,
+ ) -> Result<Self, ParseError> {
+ MetaTemplate::parse(template, Mode::Template, new_meta_vars)
}
pub(crate) fn iter(&self) -> impl Iterator<Item = &Op<S>> {
self.0.iter()
}
- fn parse(tt: &tt::Subtree<S>, mode: Mode) -> Result<Self, ParseError> {
+ fn parse(tt: &tt::Subtree<S>, mode: Mode, new_meta_vars: bool) -> Result<Self, ParseError> {
let mut src = TtIter::new(tt);
let mut res = Vec::new();
while let Some(first) = src.peek_n(0) {
- let op = next_op(first, &mut src, mode)?;
+ let op = next_op(first, &mut src, mode, new_meta_vars)?;
res.push(op);
}
@@ -51,12 +54,35 @@ impl<S: Span> MetaTemplate<S> {
#[derive(Clone, Debug, PartialEq, Eq)]
pub(crate) enum Op<S> {
- Var { name: SmolStr, kind: Option<MetaVarKind>, id: S },
- Ignore { name: SmolStr, id: S },
- Index { depth: usize },
- Count { name: SmolStr, depth: Option<usize> },
- Repeat { tokens: MetaTemplate<S>, kind: RepeatKind, separator: Option<Separator<S>> },
- Subtree { tokens: MetaTemplate<S>, delimiter: tt::Delimiter<S> },
+ Var {
+ name: SmolStr,
+ kind: Option<MetaVarKind>,
+ id: S,
+ },
+ Ignore {
+ name: SmolStr,
+ id: S,
+ },
+ Index {
+ depth: usize,
+ },
+ Length {
+ depth: usize,
+ },
+ Count {
+ name: SmolStr,
+ // FIXME: `usize`` once we drop support for 1.76
+ depth: Option<usize>,
+ },
+ Repeat {
+ tokens: MetaTemplate<S>,
+ kind: RepeatKind,
+ separator: Option<Separator<S>>,
+ },
+ Subtree {
+ tokens: MetaTemplate<S>,
+ delimiter: tt::Delimiter<S>,
+ },
Literal(tt::Literal<S>),
Punct(SmallVec<[tt::Punct<S>; 3]>),
Ident(tt::Ident<S>),
@@ -122,6 +148,7 @@ fn next_op<S: Span>(
first_peeked: &tt::TokenTree<S>,
src: &mut TtIter<'_, S>,
mode: Mode,
+ new_meta_vars: bool,
) -> Result<Op<S>, ParseError> {
let res = match first_peeked {
tt::TokenTree::Leaf(tt::Leaf::Punct(p @ tt::Punct { char: '$', .. })) => {
@@ -135,14 +162,14 @@ fn next_op<S: Span>(
tt::TokenTree::Subtree(subtree) => match subtree.delimiter.kind {
tt::DelimiterKind::Parenthesis => {
let (separator, kind) = parse_repeat(src)?;
- let tokens = MetaTemplate::parse(subtree, mode)?;
+ let tokens = MetaTemplate::parse(subtree, mode, new_meta_vars)?;
Op::Repeat { tokens, separator, kind }
}
tt::DelimiterKind::Brace => match mode {
Mode::Template => {
- parse_metavar_expr(&mut TtIter::new(subtree)).map_err(|()| {
- ParseError::unexpected("invalid metavariable expression")
- })?
+ parse_metavar_expr(new_meta_vars, &mut TtIter::new(subtree)).map_err(
+ |()| ParseError::unexpected("invalid metavariable expression"),
+ )?
}
Mode::Pattern => {
return Err(ParseError::unexpected(
@@ -206,7 +233,7 @@ fn next_op<S: Span>(
tt::TokenTree::Subtree(subtree) => {
src.next().expect("first token already peeked");
- let tokens = MetaTemplate::parse(subtree, mode)?;
+ let tokens = MetaTemplate::parse(subtree, mode, new_meta_vars)?;
Op::Subtree { tokens, delimiter: subtree.delimiter }
}
};
@@ -287,7 +314,7 @@ fn parse_repeat<S: Span>(
Err(ParseError::InvalidRepeat)
}
-fn parse_metavar_expr<S: Span>(src: &mut TtIter<'_, S>) -> Result<Op<S>, ()> {
+fn parse_metavar_expr<S: Span>(new_meta_vars: bool, src: &mut TtIter<'_, S>) -> Result<Op<S>, ()> {
let func = src.expect_ident()?;
let args = src.expect_subtree()?;
@@ -299,14 +326,19 @@ fn parse_metavar_expr<S: Span>(src: &mut TtIter<'_, S>) -> Result<Op<S>, ()> {
let op = match &*func.text {
"ignore" => {
+ if new_meta_vars {
+ args.expect_dollar()?;
+ }
let ident = args.expect_ident()?;
Op::Ignore { name: ident.text.clone(), id: ident.span }
}
"index" => Op::Index { depth: parse_depth(&mut args)? },
+ "length" => Op::Length { depth: parse_depth(&mut args)? },
"count" => {
+ if new_meta_vars {
+ args.expect_dollar()?;
+ }
let ident = args.expect_ident()?;
- // `${count(t)}` and `${count(t,)}` have different meanings. Not sure if this is a bug
- // but that's how it's implemented in rustc as of this writing. See rust-lang/rust#111904.
let depth = if try_eat_comma(&mut args) { Some(parse_depth(&mut args)?) } else { None };
Op::Count { name: ident.text.clone(), depth }
}