From 9a4c1058fac8cbbf771740928ec9a954b451c653 Mon Sep 17 00:00:00 2001
From: Oli Scherer <git-spam-no-reply9815368754983@oli-obk.de>
Date: Mon, 8 Jul 2024 09:48:12 +0000
Subject: [PATCH 1/3] Just store a span instead of the whole item
---
compiler/rustc_ast_passes/src/ast_validation.rs | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/compiler/rustc_ast_passes/src/ast_validation.rs b/compiler/rustc_ast_passes/src/ast_validation.rs
index dd0d904c52cc2..507329cc899f6 100644
--- a/compiler/rustc_ast_passes/src/ast_validation.rs
+++ b/compiler/rustc_ast_passes/src/ast_validation.rs
@@ -81,7 +81,7 @@ struct AstValidator<'a> {
features: &'a Features,
/// The span of the `extern` in an `extern { ... }` block, if any.
- extern_mod: Option<&'a Item>,
+ extern_mod: Option<Span>,
outer_trait_or_trait_impl: Option<TraitOrTraitImpl<'a>>,
@@ -579,7 +579,7 @@ impl<'a> AstValidator<'a> {
}
fn current_extern_span(&self) -> Span {
- self.session.source_map().guess_head_span(self.extern_mod.unwrap().span)
+ self.session.source_map().guess_head_span(self.extern_mod.unwrap())
}
/// An `fn` in `extern { ... }` cannot have qualifiers, e.g. `async fn`.
@@ -1080,7 +1080,7 @@ impl<'a> Visitor<'a> for AstValidator<'a> {
}
ItemKind::ForeignMod(ForeignMod { abi, safety, .. }) => {
self.with_in_extern_mod(*safety, |this| {
- let old_item = mem::replace(&mut this.extern_mod, Some(item));
+ let old_item = mem::replace(&mut this.extern_mod, Some(item.span));
this.visibility_not_permitted(
&item.vis,
errors::VisibilityNotPermittedNote::IndividualForeignItems,
From b879e29864c30d2bb2be2fffb910d66f0f4e9773 Mon Sep 17 00:00:00 2001
From: Oli Scherer <git-spam-no-reply9815368754983@oli-obk.de>
Date: Tue, 9 Jul 2024 08:54:11 +0000
Subject: [PATCH 2/3] Remove a needless borrow
---
compiler/rustc_ast_passes/src/ast_validation.rs | 14 +++++++-------
1 file changed, 7 insertions(+), 7 deletions(-)
diff --git a/compiler/rustc_ast_passes/src/ast_validation.rs b/compiler/rustc_ast_passes/src/ast_validation.rs
index 507329cc899f6..45c6211598bec 100644
--- a/compiler/rustc_ast_passes/src/ast_validation.rs
+++ b/compiler/rustc_ast_passes/src/ast_validation.rs
@@ -61,12 +61,12 @@ enum DisallowTildeConstContext<'a> {
Item,
}
-enum TraitOrTraitImpl<'a> {
+enum TraitOrTraitImpl {
Trait { span: Span, constness: Option<Span> },
- TraitImpl { constness: Const, polarity: ImplPolarity, trait_ref: &'a TraitRef },
+ TraitImpl { constness: Const, polarity: ImplPolarity, trait_ref: Span },
}
-impl<'a> TraitOrTraitImpl<'a> {
+impl TraitOrTraitImpl {
fn constness(&self) -> Option<Span> {
match self {
Self::Trait { constness: Some(span), .. }
@@ -83,7 +83,7 @@ struct AstValidator<'a> {
/// The span of the `extern` in an `extern { ... }` block, if any.
extern_mod: Option<Span>,
- outer_trait_or_trait_impl: Option<TraitOrTraitImpl<'a>>,
+ outer_trait_or_trait_impl: Option<TraitOrTraitImpl>,
has_proc_macro_decls: bool,
@@ -115,7 +115,7 @@ impl<'a> AstValidator<'a> {
trait_.map(|(constness, polarity, trait_ref)| TraitOrTraitImpl::TraitImpl {
constness,
polarity,
- trait_ref,
+ trait_ref: trait_ref.path.span,
}),
);
f(self);
@@ -354,7 +354,7 @@ impl<'a> AstValidator<'a> {
}
}
- fn check_trait_fn_not_const(&self, constness: Const, parent: &TraitOrTraitImpl<'a>) {
+ fn check_trait_fn_not_const(&self, constness: Const, parent: &TraitOrTraitImpl) {
let Const::Yes(span) = constness else {
return;
};
@@ -367,7 +367,7 @@ impl<'a> AstValidator<'a> {
..
} = parent
{
- Some(trait_ref.path.span.shrink_to_lo())
+ Some(trait_ref.shrink_to_lo())
} else {
None
};
From d9f959292464c7bd68672801a42113e5b6d262b8 Mon Sep 17 00:00:00 2001
From: Oli Scherer <git-spam-no-reply9815368754983@oli-obk.de>
Date: Tue, 9 Jul 2024 09:54:19 +0000
Subject: [PATCH 3/3] Remove a boilerplaty abstraction
---
.../rustc_ast_passes/src/ast_validation.rs | 76 ++++---------------
compiler/rustc_ast_passes/src/errors.rs | 2 +-
2 files changed, 17 insertions(+), 61 deletions(-)
diff --git a/compiler/rustc_ast_passes/src/ast_validation.rs b/compiler/rustc_ast_passes/src/ast_validation.rs
index 45c6211598bec..e6cc2e4069b7e 100644
--- a/compiler/rustc_ast_passes/src/ast_validation.rs
+++ b/compiler/rustc_ast_passes/src/ast_validation.rs
@@ -38,7 +38,7 @@ use std::mem;
use std::ops::{Deref, DerefMut};
use thin_vec::thin_vec;
-use crate::errors;
+use crate::errors::{self, TildeConstReason};
/// Is `self` allowed semantically as the first parameter in an `FnDecl`?
enum SelfSemantic {
@@ -46,21 +46,6 @@ enum SelfSemantic {
No,
}
-/// What is the context that prevents using `~const`?
-// FIXME(effects): Consider getting rid of this in favor of `errors::TildeConstReason`, they're
-// almost identical. This gets rid of an abstraction layer which might be considered bad.
-enum DisallowTildeConstContext<'a> {
- TraitObject,
- Fn(FnKind<'a>),
- Trait(Span),
- TraitImpl(Span),
- Impl(Span),
- TraitAssocTy(Span),
- TraitImplAssocTy(Span),
- InherentAssocTy(Span),
- Item,
-}
-
enum TraitOrTraitImpl {
Trait { span: Span, constness: Option<Span> },
TraitImpl { constness: Const, polarity: ImplPolarity, trait_ref: Span },
@@ -92,7 +77,7 @@ struct AstValidator<'a> {
/// e.g., `impl Iterator<Item = impl Debug>`.
outer_impl_trait: Option<Span>,
- disallow_tilde_const: Option<DisallowTildeConstContext<'a>>,
+ disallow_tilde_const: Option<TildeConstReason>,
/// Used to ban `impl Trait` in path projections like `<impl Iterator>::Item`
/// or `Foo::Bar<impl Trait>`
@@ -145,7 +130,7 @@ impl<'a> AstValidator<'a> {
fn with_tilde_const(
&mut self,
- disallowed: Option<DisallowTildeConstContext<'a>>,
+ disallowed: Option<TildeConstReason>,
f: impl FnOnce(&mut Self),
) {
let old = mem::replace(&mut self.disallow_tilde_const, disallowed);
@@ -224,7 +209,7 @@ impl<'a> AstValidator<'a> {
}
}
TyKind::TraitObject(..) => self
- .with_tilde_const(Some(DisallowTildeConstContext::TraitObject), |this| {
+ .with_tilde_const(Some(TildeConstReason::TraitObject), |this| {
visit::walk_ty(this, t)
}),
TyKind::Path(qself, path) => {
@@ -980,7 +965,7 @@ impl<'a> Visitor<'a> for AstValidator<'a> {
this.visit_vis(&item.vis);
this.visit_ident(item.ident);
let disallowed = matches!(constness, Const::No)
- .then(|| DisallowTildeConstContext::TraitImpl(item.span));
+ .then(|| TildeConstReason::TraitImpl { span: item.span });
this.with_tilde_const(disallowed, |this| this.visit_generics(generics));
this.visit_trait_ref(t);
this.visit_ty(self_ty);
@@ -1035,7 +1020,7 @@ impl<'a> Visitor<'a> for AstValidator<'a> {
this.visit_vis(&item.vis);
this.visit_ident(item.ident);
this.with_tilde_const(
- Some(DisallowTildeConstContext::Impl(item.span)),
+ Some(TildeConstReason::Impl { span: item.span }),
|this| this.visit_generics(generics),
);
this.visit_ty(self_ty);
@@ -1154,7 +1139,7 @@ impl<'a> Visitor<'a> for AstValidator<'a> {
this.visit_ident(item.ident);
let disallowed = is_const_trait
.is_none()
- .then(|| DisallowTildeConstContext::Trait(item.span));
+ .then(|| TildeConstReason::Trait { span: item.span });
this.with_tilde_const(disallowed, |this| {
this.visit_generics(generics);
walk_list!(this, visit_param_bound, bounds, BoundKind::SuperTraits)
@@ -1399,40 +1384,8 @@ impl<'a> Visitor<'a> for AstValidator<'a> {
self.dcx().emit_err(errors::ConstBoundTraitObject { span: trait_ref.span });
}
(_, BoundConstness::Maybe(span), BoundPolarity::Positive)
- if let Some(reason) = &self.disallow_tilde_const =>
+ if let Some(reason) = self.disallow_tilde_const =>
{
- let reason = match reason {
- DisallowTildeConstContext::Fn(FnKind::Closure(..)) => {
- errors::TildeConstReason::Closure
- }
- DisallowTildeConstContext::Fn(FnKind::Fn(_, ident, ..)) => {
- errors::TildeConstReason::Function { ident: ident.span }
- }
- &DisallowTildeConstContext::Trait(span) => {
- errors::TildeConstReason::Trait { span }
- }
- &DisallowTildeConstContext::TraitImpl(span) => {
- errors::TildeConstReason::TraitImpl { span }
- }
- &DisallowTildeConstContext::Impl(span) => {
- // FIXME(effects): Consider providing a help message or even a structured
- // suggestion for moving such bounds to the assoc const fns if available.
- errors::TildeConstReason::Impl { span }
- }
- &DisallowTildeConstContext::TraitAssocTy(span) => {
- errors::TildeConstReason::TraitAssocTy { span }
- }
- &DisallowTildeConstContext::TraitImplAssocTy(span) => {
- errors::TildeConstReason::TraitImplAssocTy { span }
- }
- &DisallowTildeConstContext::InherentAssocTy(span) => {
- errors::TildeConstReason::InherentAssocTy { span }
- }
- DisallowTildeConstContext::TraitObject => {
- errors::TildeConstReason::TraitObject
- }
- DisallowTildeConstContext::Item => errors::TildeConstReason::Item,
- };
self.dcx().emit_err(errors::TildeConstDisallowed { span, reason });
}
(
@@ -1569,7 +1522,10 @@ impl<'a> Visitor<'a> for AstValidator<'a> {
.and_then(TraitOrTraitImpl::constness)
.is_some();
- let disallowed = (!tilde_const_allowed).then(|| DisallowTildeConstContext::Fn(fk));
+ let disallowed = (!tilde_const_allowed).then(|| match fk {
+ FnKind::Fn(_, ident, _, _, _, _) => TildeConstReason::Function { ident: ident.span },
+ FnKind::Closure(_, _, _) => TildeConstReason::Closure,
+ });
self.with_tilde_const(disallowed, |this| visit::walk_fn(this, fk));
}
@@ -1664,12 +1620,12 @@ impl<'a> Visitor<'a> for AstValidator<'a> {
AssocItemKind::Type(_) => {
let disallowed = (!parent_is_const).then(|| match self.outer_trait_or_trait_impl {
Some(TraitOrTraitImpl::Trait { .. }) => {
- DisallowTildeConstContext::TraitAssocTy(item.span)
+ TildeConstReason::TraitAssocTy { span: item.span }
}
Some(TraitOrTraitImpl::TraitImpl { .. }) => {
- DisallowTildeConstContext::TraitImplAssocTy(item.span)
+ TildeConstReason::TraitImplAssocTy { span: item.span }
}
- None => DisallowTildeConstContext::InherentAssocTy(item.span),
+ None => TildeConstReason::InherentAssocTy { span: item.span },
});
self.with_tilde_const(disallowed, |this| {
this.with_in_trait_impl(None, |this| visit::walk_assoc_item(this, item, ctxt))
@@ -1852,7 +1808,7 @@ pub fn check_crate(
outer_trait_or_trait_impl: None,
has_proc_macro_decls: false,
outer_impl_trait: None,
- disallow_tilde_const: Some(DisallowTildeConstContext::Item),
+ disallow_tilde_const: Some(TildeConstReason::Item),
is_impl_trait_banned: false,
extern_mod_safety: None,
lint_buffer: lints,
diff --git a/compiler/rustc_ast_passes/src/errors.rs b/compiler/rustc_ast_passes/src/errors.rs
index bfb9047645011..2c18b47f0f7f0 100644
--- a/compiler/rustc_ast_passes/src/errors.rs
+++ b/compiler/rustc_ast_passes/src/errors.rs
@@ -612,7 +612,7 @@ pub struct TildeConstDisallowed {
pub reason: TildeConstReason,
}
-#[derive(Subdiagnostic)]
+#[derive(Subdiagnostic, Copy, Clone)]
pub enum TildeConstReason {
#[note(ast_passes_closure)]
Closure,