diff options
| -rw-r--r-- | compiler/rustc_builtin_macros/src/cfg_eval.rs | 102 |
1 files changed, 45 insertions, 57 deletions
diff --git a/compiler/rustc_builtin_macros/src/cfg_eval.rs b/compiler/rustc_builtin_macros/src/cfg_eval.rs index f0f534fe2e7..b8a477b2b34 100644 --- a/compiler/rustc_builtin_macros/src/cfg_eval.rs +++ b/compiler/rustc_builtin_macros/src/cfg_eval.rs @@ -83,7 +83,7 @@ impl CfgEval<'_> { self.0.configure(node) } - fn configure_annotatable(mut self, mut annotatable: Annotatable) -> Annotatable { + fn configure_annotatable(mut self, annotatable: Annotatable) -> Annotatable { // Tokenizing and re-parsing the `Annotatable` can have a significant // performance impact, so try to avoid it if possible if !has_cfg_or_cfg_attr(&annotatable) { @@ -100,39 +100,6 @@ 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: for<'a> fn(&mut Parser<'a>) -> PResult<'a, _> = - match annotatable { - Annotatable::Item(_) => { - |parser| Ok(Annotatable::Item(parser.parse_item(ForceCollect::Yes)?.unwrap())) - } - Annotatable::AssocItem(_, AssocCtxt::Trait) => |parser| { - Ok(Annotatable::AssocItem( - parser.parse_trait_item(ForceCollect::Yes)?.unwrap().unwrap(), - AssocCtxt::Trait, - )) - }, - Annotatable::AssocItem(_, AssocCtxt::Impl) => |parser| { - Ok(Annotatable::AssocItem( - parser.parse_impl_item(ForceCollect::Yes)?.unwrap().unwrap(), - AssocCtxt::Impl, - )) - }, - Annotatable::ForeignItem(_) => |parser| { - Ok(Annotatable::ForeignItem( - parser.parse_foreign_item(ForceCollect::Yes)?.unwrap().unwrap(), - )) - }, - Annotatable::Stmt(_) => |parser| { - Ok(Annotatable::Stmt(P(parser - .parse_stmt_without_recovery(false, 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 // is normally delayed until the proc-macro server actually needs to @@ -151,34 +118,55 @@ impl CfgEval<'_> { // Re-parse the tokens, setting the `capture_cfg` flag to save extra information // to the captured `AttrTokenStream` (specifically, we capture // `AttrTokenTree::AttrsTarget` for all occurrences of `#[cfg]` and `#[cfg_attr]`) + // + // After that we have our re-parsed `AttrTokenStream`, recursively configuring + // our attribute target will correctly configure the tokens as well. let mut parser = Parser::new(&self.0.sess.psess, orig_tokens, None); parser.capture_cfg = true; - match parse_annotatable_with(&mut parser) { - Ok(a) => annotatable = a, - Err(err) => { - err.emit(); - return annotatable; + let res: PResult<'_, Annotatable> = try { + match annotatable { + Annotatable::Item(_) => { + let item = parser.parse_item(ForceCollect::Yes)?.unwrap(); + Annotatable::Item(self.flat_map_item(item).pop().unwrap()) + } + Annotatable::AssocItem(_, AssocCtxt::Trait) => { + let item = parser.parse_trait_item(ForceCollect::Yes)?.unwrap().unwrap(); + Annotatable::AssocItem( + self.flat_map_assoc_item(item, AssocCtxt::Trait).pop().unwrap(), + AssocCtxt::Trait, + ) + } + Annotatable::AssocItem(_, AssocCtxt::Impl) => { + let item = parser.parse_impl_item(ForceCollect::Yes)?.unwrap().unwrap(); + Annotatable::AssocItem( + self.flat_map_assoc_item(item, AssocCtxt::Impl).pop().unwrap(), + AssocCtxt::Impl, + ) + } + Annotatable::ForeignItem(_) => { + let item = parser.parse_foreign_item(ForceCollect::Yes)?.unwrap().unwrap(); + Annotatable::ForeignItem(self.flat_map_foreign_item(item).pop().unwrap()) + } + Annotatable::Stmt(_) => { + let stmt = + parser.parse_stmt_without_recovery(false, ForceCollect::Yes)?.unwrap(); + Annotatable::Stmt(P(self.flat_map_stmt(stmt).pop().unwrap())) + } + Annotatable::Expr(_) => { + let mut expr = parser.parse_expr_force_collect()?; + self.visit_expr(&mut expr); + Annotatable::Expr(expr) + } + _ => unreachable!(), } - } + }; - // Now that we have our re-parsed `AttrTokenStream`, recursively configuring - // our attribute target will correctly configure the tokens as well. - match annotatable { - Annotatable::Item(item) => Annotatable::Item(self.flat_map_item(item).pop().unwrap()), - Annotatable::AssocItem(item, ctxt) => { - Annotatable::AssocItem(self.flat_map_assoc_item(item, ctxt).pop().unwrap(), ctxt) - } - Annotatable::ForeignItem(item) => { - Annotatable::ForeignItem(self.flat_map_foreign_item(item).pop().unwrap()) - } - Annotatable::Stmt(stmt) => { - Annotatable::Stmt(P(self.flat_map_stmt(stmt.into_inner()).pop().unwrap())) - } - Annotatable::Expr(mut expr) => { - self.visit_expr(&mut expr); - Annotatable::Expr(expr) + match res { + Ok(ann) => ann, + Err(err) => { + err.emit(); + annotatable } - _ => unreachable!(), } } } |