Emit an error instead of reconstructing token stream.

This commit is contained in:
Camille GILLOT 2022-08-08 19:17:37 +02:00
parent 8823634db8
commit cb5ea8d0b6
4 changed files with 58 additions and 59 deletions

View file

@ -7,6 +7,7 @@ use rustc_ast::visit::Visitor;
use rustc_ast::NodeId;
use rustc_ast::{mut_visit, visit};
use rustc_ast::{Attribute, HasAttrs, HasTokens};
use rustc_errors::PResult;
use rustc_expand::base::{Annotatable, ExtCtxt};
use rustc_expand::config::StripUnconfigured;
use rustc_expand::configure;
@ -144,33 +145,34 @@ impl CfgEval<'_, '_> {
// the location of `#[cfg]` and `#[cfg_attr]` in the token stream. The tokenization
// process is lossless, so this process is invisible to proc-macros.
let parse_annotatable_with: fn(&mut Parser<'_>) -> _ = match annotatable {
Annotatable::Item(_) => {
|parser| Annotatable::Item(parser.parse_item(ForceCollect::Yes).unwrap().unwrap())
}
Annotatable::TraitItem(_) => |parser| {
Annotatable::TraitItem(
parser.parse_trait_item(ForceCollect::Yes).unwrap().unwrap().unwrap(),
)
},
Annotatable::ImplItem(_) => |parser| {
Annotatable::ImplItem(
parser.parse_impl_item(ForceCollect::Yes).unwrap().unwrap().unwrap(),
)
},
Annotatable::ForeignItem(_) => |parser| {
Annotatable::ForeignItem(
parser.parse_foreign_item(ForceCollect::Yes).unwrap().unwrap().unwrap(),
)
},
Annotatable::Stmt(_) => |parser| {
Annotatable::Stmt(P(parser.parse_stmt(ForceCollect::Yes).unwrap().unwrap()))
},
Annotatable::Expr(_) => {
|parser| Annotatable::Expr(parser.parse_expr_force_collect().unwrap())
}
_ => unreachable!(),
};
let parse_annotatable_with: for<'a> fn(&mut Parser<'a>) -> PResult<'a, _> =
match annotatable {
Annotatable::Item(_) => {
|parser| Ok(Annotatable::Item(parser.parse_item(ForceCollect::Yes)?.unwrap()))
}
Annotatable::TraitItem(_) => |parser| {
Ok(Annotatable::TraitItem(
parser.parse_trait_item(ForceCollect::Yes)?.unwrap().unwrap(),
))
},
Annotatable::ImplItem(_) => |parser| {
Ok(Annotatable::ImplItem(
parser.parse_impl_item(ForceCollect::Yes)?.unwrap().unwrap(),
))
},
Annotatable::ForeignItem(_) => |parser| {
Ok(Annotatable::ForeignItem(
parser.parse_foreign_item(ForceCollect::Yes)?.unwrap().unwrap(),
))
},
Annotatable::Stmt(_) => |parser| {
Ok(Annotatable::Stmt(P(parser.parse_stmt(ForceCollect::Yes)?.unwrap())))
},
Annotatable::Expr(_) => {
|parser| Ok(Annotatable::Expr(parser.parse_expr_force_collect()?))
}
_ => unreachable!(),
};
// 'Flatten' all nonterminals (i.e. `TokenKind::Interpolated`)
// to `None`-delimited groups containing the corresponding tokens. This
@ -193,7 +195,13 @@ impl CfgEval<'_, '_> {
let mut parser =
rustc_parse::stream_to_parser(&self.cfg.sess.parse_sess, orig_tokens, None);
parser.capture_cfg = true;
annotatable = parse_annotatable_with(&mut parser);
match parse_annotatable_with(&mut parser) {
Ok(a) => annotatable = a,
Err(mut err) => {
err.emit();
return Some(annotatable);
}
}
// Now that we have our re-parsed `AttrTokenStream`, recursively configuring
// our attribute target will correctly the tokens as well.