Unnamed repository; edit this file 'description' to name the repository.
Diffstat (limited to 'crates/mbe/src/lib.rs')
| -rw-r--r-- | crates/mbe/src/lib.rs | 86 |
1 files changed, 38 insertions, 48 deletions
diff --git a/crates/mbe/src/lib.rs b/crates/mbe/src/lib.rs index 62e7509eb3..8d223c375a 100644 --- a/crates/mbe/src/lib.rs +++ b/crates/mbe/src/lib.rs @@ -27,6 +27,14 @@ use crate::{ pub use ::parser::TopEntryPoint; pub use tt::{Delimiter, DelimiterKind, Punct}; +pub use crate::{ + syntax_bridge::{ + parse_exprs_with_sep, parse_to_token_tree, syntax_node_to_token_tree, + syntax_node_to_token_tree_censored, token_tree_to_syntax_node, + }, + token_map::TokenMap, +}; + #[derive(Debug, PartialEq, Eq, Clone)] pub enum ParseError { UnexpectedToken(String), @@ -70,14 +78,6 @@ impl fmt::Display for ExpandError { } } -pub use crate::{ - syntax_bridge::{ - parse_exprs_with_sep, parse_to_token_tree, syntax_node_to_token_tree, - syntax_node_to_token_tree_censored, token_tree_to_syntax_node, - }, - token_map::TokenMap, -}; - /// This struct contains AST for a single `macro_rules` definition. What might /// be very confusing is that AST has almost exactly the same shape as /// `tt::TokenTree`, but there's a crucial difference: in macro rules, `$ident` @@ -121,11 +121,9 @@ impl Shift { } } tt::TokenTree::Leaf(leaf) => { - let id = match leaf { - tt::Leaf::Literal(it) => it.id, - tt::Leaf::Punct(it) => it.id, - tt::Leaf::Ident(it) => it.id, - }; + let &(tt::Leaf::Ident(tt::Ident { id, .. }) + | tt::Leaf::Punct(tt::Punct { id, .. }) + | tt::Leaf::Literal(tt::Literal { id, .. })) = leaf; (id != tt::TokenId::unspecified()).then(|| id.0) } @@ -138,15 +136,15 @@ impl Shift { pub fn shift_all(self, tt: &mut tt::Subtree) { for t in &mut tt.token_trees { match t { - tt::TokenTree::Leaf(leaf) => match leaf { - tt::Leaf::Ident(ident) => ident.id = self.shift(ident.id), - tt::Leaf::Punct(punct) => punct.id = self.shift(punct.id), - tt::Leaf::Literal(lit) => lit.id = self.shift(lit.id), - }, + tt::TokenTree::Leaf( + tt::Leaf::Ident(tt::Ident { id, .. }) + | tt::Leaf::Punct(tt::Punct { id, .. }) + | tt::Leaf::Literal(tt::Literal { id, .. }), + ) => *id = self.shift(*id), tt::TokenTree::Subtree(tt) => { if let Some(it) = tt.delimiter.as_mut() { it.id = self.shift(it.id); - }; + } self.shift_all(tt) } } @@ -155,9 +153,10 @@ impl Shift { pub fn shift(self, id: tt::TokenId) -> tt::TokenId { if id == tt::TokenId::unspecified() { - return id; + id + } else { + tt::TokenId(id.0 + self.0) } - tt::TokenId(id.0 + self.0) } pub fn unshift(self, id: tt::TokenId) -> Option<tt::TokenId> { @@ -190,8 +189,8 @@ impl DeclarativeMacro { } } - for rule in &rules { - validate(&rule.lhs)?; + for Rule { lhs, .. } in &rules { + validate(lhs)?; } Ok(DeclarativeMacro { rules, shift: Shift::new(tt) }) @@ -220,12 +219,13 @@ impl DeclarativeMacro { cov_mark::hit!(parse_macro_def_simple); let rule = Rule::parse(&mut src, false)?; if src.len() != 0 { - return Err(ParseError::Expected("remain tokens in macro def".to_string())); + return Err(ParseError::Expected("remaining tokens in macro def".to_string())); } rules.push(rule); } - for rule in &rules { - validate(&rule.lhs)?; + + for Rule { lhs, .. } in &rules { + validate(lhs)?; } Ok(DeclarativeMacro { rules, shift: Shift::new(tt) }) @@ -281,28 +281,18 @@ fn validate(pattern: &MetaTemplate) -> Result<(), ParseError> { Op::Repeat { tokens: subtree, separator, .. } => { // Checks that no repetition which could match an empty token // https://github.com/rust-lang/rust/blob/a58b1ed44f5e06976de2bdc4d7dc81c36a96934f/src/librustc_expand/mbe/macro_rules.rs#L558 - - if separator.is_none() - && subtree.iter().all(|child_op| { - match child_op { - Op::Var { kind, .. } => { - // vis is optional - if kind.as_ref().map_or(false, |it| it == "vis") { - return true; - } - } - Op::Repeat { kind, .. } => { - return matches!( - kind, - parser::RepeatKind::ZeroOrMore | parser::RepeatKind::ZeroOrOne - ) - } - Op::Leaf(_) => {} - Op::Subtree { .. } => {} - } - false - }) - { + let lsh_is_empty_seq = separator.is_none() && subtree.iter().all(|child_op| { + match child_op { + // vis is optional + Op::Var { kind: Some(kind), .. } => kind == "vis", + Op::Repeat { + kind: parser::RepeatKind::ZeroOrMore | parser::RepeatKind::ZeroOrOne, + .. + } => true, + _ => false, + } + }); + if lsh_is_empty_seq { return Err(ParseError::RepetitionEmptyTokenTree); } validate(subtree)? |