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Move in_trait into OpaqueTyOrigin

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This commit is contained in:
Michael Goulet
2024-10-02 22:21:37 -04:00
parent cb7e3695e8
commit 7cd466a036
19 changed files with 146 additions and 125 deletions
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80
compiler/rustc_ast_lowering/src/lib.rs
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@@ -288,12 +288,7 @@ enum ImplTraitContext {
/// Example: `fn foo() -> impl Debug`, where `impl Debug` is conceptually
/// equivalent to a new opaque type like `type T = impl Debug; fn foo() -> T`.
///
OpaqueTy {
origin: hir::OpaqueTyOrigin,
/// Only used to change the lifetime capture rules, since
/// RPITIT captures all in scope, RPIT does not.
fn_kind: Option<FnDeclKind>,
},
OpaqueTy { origin: hir::OpaqueTyOrigin },
/// `impl Trait` is unstably accepted in this position.
FeatureGated(ImplTraitPosition, Symbol),
/// `impl Trait` is not accepted in this position.
@@ -1404,14 +1399,9 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
TyKind::ImplTrait(def_node_id, bounds) => {
let span = t.span;
match itctx {
ImplTraitContext::OpaqueTy { origin, fn_kind } => self.lower_opaque_impl_trait(
span,
origin,
*def_node_id,
bounds,
fn_kind,
itctx,
),
ImplTraitContext::OpaqueTy { origin } => {
self.lower_opaque_impl_trait(span, origin, *def_node_id, bounds, itctx)
}
ImplTraitContext::Universal => {
if let Some(span) = bounds.iter().find_map(|bound| match *bound {
ast::GenericBound::Use(_, span) => Some(span),
@@ -1513,7 +1503,6 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
origin: hir::OpaqueTyOrigin,
opaque_ty_node_id: NodeId,
bounds: &GenericBounds,
fn_kind: Option<FnDeclKind>,
itctx: ImplTraitContext,
) -> hir::TyKind<'hir> {
// Make sure we know that some funky desugaring has been going on here.
@@ -1555,11 +1544,9 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
.map(|(ident, id, _)| Lifetime { id, ident })
.collect()
}
hir::OpaqueTyOrigin::FnReturn { .. } => {
if matches!(
fn_kind.expect("expected RPITs to be lowered with a FnKind"),
FnDeclKind::Impl | FnDeclKind::Trait
) || self.tcx.features().lifetime_capture_rules_2024
hir::OpaqueTyOrigin::FnReturn { in_trait_or_impl, .. } => {
if in_trait_or_impl.is_some()
|| self.tcx.features().lifetime_capture_rules_2024
|| span.at_least_rust_2024()
{
// return-position impl trait in trait was decided to capture all
@@ -1583,9 +1570,9 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
};
debug!(?captured_lifetimes_to_duplicate);
match fn_kind {
// Deny `use<>` on RPITIT in trait/trait-impl for now.
Some(FnDeclKind::Trait | FnDeclKind::Impl) => {
// Feature gate for RPITIT + use<..>
match origin {
rustc_hir::OpaqueTyOrigin::FnReturn { in_trait_or_impl: Some(_), .. } => {
if let Some(span) = bounds.iter().find_map(|bound| match *bound {
ast::GenericBound::Use(_, span) => Some(span),
_ => None,
@@ -1593,20 +1580,12 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
self.tcx.dcx().emit_err(errors::NoPreciseCapturesOnRpitit { span });
}
}
None
| Some(
FnDeclKind::Fn
| FnDeclKind::Inherent
| FnDeclKind::ExternFn
| FnDeclKind::Closure
| FnDeclKind::Pointer,
) => {}
_ => {}
}
self.lower_opaque_inner(
opaque_ty_node_id,
origin,
matches!(fn_kind, Some(FnDeclKind::Trait)),
captured_lifetimes_to_duplicate,
span,
opaque_ty_span,
@@ -1618,7 +1597,6 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
&mut self,
opaque_ty_node_id: NodeId,
origin: hir::OpaqueTyOrigin,
in_trait: bool,
captured_lifetimes_to_duplicate: FxIndexSet<Lifetime>,
span: Span,
opaque_ty_span: Span,
@@ -1747,7 +1725,6 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
bounds,
origin,
lifetime_mapping,
in_trait,
};
// Generate an `type Foo = impl Trait;` declaration.
@@ -1863,14 +1840,23 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
None => match &decl.output {
FnRetTy::Ty(ty) => {
let itctx = match kind {
FnDeclKind::Fn
| FnDeclKind::Inherent
| FnDeclKind::Trait
| FnDeclKind::Impl => ImplTraitContext::OpaqueTy {
FnDeclKind::Fn | FnDeclKind::Inherent => ImplTraitContext::OpaqueTy {
origin: hir::OpaqueTyOrigin::FnReturn {
parent: self.local_def_id(fn_node_id),
in_trait_or_impl: None,
},
},
FnDeclKind::Trait => ImplTraitContext::OpaqueTy {
origin: hir::OpaqueTyOrigin::FnReturn {
parent: self.local_def_id(fn_node_id),
in_trait_or_impl: Some(hir::RpitContext::Trait),
},
},
FnDeclKind::Impl => ImplTraitContext::OpaqueTy {
origin: hir::OpaqueTyOrigin::FnReturn {
parent: self.local_def_id(fn_node_id),
in_trait_or_impl: Some(hir::RpitContext::TraitImpl),
},
fn_kind: Some(kind),
},
FnDeclKind::ExternFn => {
ImplTraitContext::Disallowed(ImplTraitPosition::ExternFnReturn)
@@ -1952,10 +1938,16 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
.map(|(ident, id, _)| Lifetime { id, ident })
.collect();
let in_trait_or_impl = match fn_kind {
FnDeclKind::Trait => Some(hir::RpitContext::Trait),
FnDeclKind::Impl => Some(hir::RpitContext::TraitImpl),
FnDeclKind::Fn | FnDeclKind::Inherent => None,
FnDeclKind::ExternFn | FnDeclKind::Closure | FnDeclKind::Pointer => unreachable!(),
};
let opaque_ty_ref = self.lower_opaque_inner(
opaque_ty_node_id,
hir::OpaqueTyOrigin::AsyncFn { parent: fn_def_id },
matches!(fn_kind, FnDeclKind::Trait),
hir::OpaqueTyOrigin::AsyncFn { parent: fn_def_id, in_trait_or_impl },
captured_lifetimes,
span,
opaque_ty_span,
@@ -1965,8 +1957,10 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
coro,
opaque_ty_span,
ImplTraitContext::OpaqueTy {
origin: hir::OpaqueTyOrigin::FnReturn { parent: fn_def_id },
fn_kind: Some(fn_kind),
origin: hir::OpaqueTyOrigin::FnReturn {
parent: fn_def_id,
in_trait_or_impl,
},
},
);
arena_vec![this; bound]