Improve errors on unexpected token in precise capture bound

dtolnay · Jul 21, 2024 · 788f8cb · 788f8cb
1 parent 11b2371
commit 788f8cb
Showing 1 changed file with 12 additions and 6 deletions.
diff --git a/src/generics.rs b/src/generics.rs
@@ -775,18 +775,24 @@ pub(crate) mod parsing {
  if cfg!(feature = "full") && input.peek(Token![use]) {
  input.parse::<Token![use]>()?;
  input.parse::<Token![<]>()?;
- while !input.peek(Token![>]) {
- if input.peek(Lifetime) {
+ loop {
+ let lookahead = input.lookahead1();
+ if lookahead.peek(Lifetime) {
  input.parse::<Lifetime>()?;
- } else if input.peek(Ident) {
+ } else if lookahead.peek(Ident) {
  input.parse::<Ident>()?;
- } else {
+ } else if lookahead.peek(Token![>]) {
  break;
+ } else {
+ return Err(lookahead.error());
  }
- if input.peek(Token![,]) {
+ let lookahead = input.lookahead1();
+ if lookahead.peek(Token![,]) {
  input.parse::<Token![,]>()?;
- } else {
+ } else if lookahead.peek(Token![>]) {
  break;
+ } else {
+ return Err(lookahead.error());
  }
  }
  input.parse::<Token![>]>()?;