Improve the impl and diag output of lint type_alias_bounds

This commit is contained in:
León Orell Valerian Liehr 2024-06-15 21:34:44 +02:00
parent a8b3dfd253
commit fdf8f024ad
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GPG key ID: D17A07215F68E713
13 changed files with 385 additions and 319 deletions

View file

@ -139,13 +139,18 @@ lint_builtin_special_module_name_used_main = found module declaration for main.r
lint_builtin_trivial_bounds = {$predicate_kind_name} bound {$predicate} does not depend on any type or lifetime parameters
lint_builtin_type_alias_bounds_help = use fully disambiguated paths (i.e., `<T as Trait>::Assoc`) to refer to associated types in type aliases
lint_builtin_type_alias_generic_bounds = bounds on generic parameters are not enforced in type aliases
.suggestion = the bound will not be checked when the type alias is used, and should be removed
lint_builtin_type_alias_where_clause = where clauses are not enforced in type aliases
.suggestion = the clause will not be checked when the type alias is used, and should be removed
lint_builtin_type_alias_bounds_enable_feat_help = add `#![feature(lazy_type_alias)]` to the crate attributes to enable the desired semantics
lint_builtin_type_alias_bounds_label = will not be checked at usage sites of the type alias
lint_builtin_type_alias_bounds_limitation_note = this is a known limitation of the type checker that may be lifted in a future edition.
see issue #112792 <https://github.com/rust-lang/rust/issues/112792> for more information
lint_builtin_type_alias_bounds_param_bounds = bounds on generic parameters in type aliases are not enforced
.suggestion = remove {$count ->
[one] this bound
*[other] these bounds
}
lint_builtin_type_alias_bounds_qualify_assoc_tys_sugg = fully qualify this associated type
lint_builtin_type_alias_bounds_where_clause = where clauses on type aliases are not enforced
.suggestion = remove this where clause
lint_builtin_unpermitted_type_init_label = this code causes undefined behavior when executed
lint_builtin_unpermitted_type_init_label_suggestion = help: use `MaybeUninit<T>` instead, and only call `assume_init` after initialization is done

View file

@ -31,12 +31,12 @@ use crate::{
BuiltinIncompleteFeaturesHelp, BuiltinInternalFeatures, BuiltinKeywordIdents,
BuiltinMissingCopyImpl, BuiltinMissingDebugImpl, BuiltinMissingDoc,
BuiltinMutablesTransmutes, BuiltinNoMangleGeneric, BuiltinNonShorthandFieldPatterns,
BuiltinSpecialModuleNameUsed, BuiltinTrivialBounds, BuiltinTypeAliasGenericBounds,
BuiltinTypeAliasGenericBoundsSuggestion, BuiltinTypeAliasWhereClause,
BuiltinUngatedAsyncFnTrackCaller, BuiltinUnpermittedTypeInit,
BuiltinUnpermittedTypeInitSub, BuiltinUnreachablePub, BuiltinUnsafe,
BuiltinUnstableFeatures, BuiltinUnusedDocComment, BuiltinUnusedDocCommentSub,
BuiltinWhileTrue, InvalidAsmLabel, SuggestChangingAssocTypes,
BuiltinSpecialModuleNameUsed, BuiltinTrivialBounds, BuiltinTypeAliasBounds,
BuiltinTypeAliasParamBoundsSuggestion, BuiltinUngatedAsyncFnTrackCaller,
BuiltinUnpermittedTypeInit, BuiltinUnpermittedTypeInitSub, BuiltinUnreachablePub,
BuiltinUnsafe, BuiltinUnstableFeatures, BuiltinUnusedDocComment,
BuiltinUnusedDocCommentSub, BuiltinWhileTrue, InvalidAsmLabel,
TypeAliasBoundsQualifyAssocTysSugg,
},
EarlyContext, EarlyLintPass, LateContext, LateLintPass, Level, LintContext,
};
@ -1406,23 +1406,6 @@ declare_lint_pass!(
TypeAliasBounds => [TYPE_ALIAS_BOUNDS]
);
impl TypeAliasBounds {
pub(crate) fn is_type_variable_assoc(qpath: &hir::QPath<'_>) -> bool {
match *qpath {
hir::QPath::TypeRelative(ty, _) => {
// If this is a type variable, we found a `T::Assoc`.
match ty.kind {
hir::TyKind::Path(hir::QPath::Resolved(None, path)) => {
matches!(path.res, Res::Def(DefKind::TyParam, _))
}
_ => false,
}
}
hir::QPath::Resolved(..) | hir::QPath::LangItem(..) => false,
}
}
}
impl<'tcx> LateLintPass<'tcx> for TypeAliasBounds {
fn check_item(&mut self, cx: &LateContext<'_>, item: &hir::Item<'_>) {
let hir::ItemKind::TyAlias(hir_ty, generics) = &item.kind else { return };
@ -1437,7 +1420,6 @@ impl<'tcx> LateLintPass<'tcx> for TypeAliasBounds {
return;
}
// FIXME(generic_const_exprs): Revisit this before stabilization.
// See also `tests/ui/const-generics/generic_const_exprs/type-alias-bounds.rs`.
let ty = cx.tcx.type_of(item.owner_id).instantiate_identity();
@ -1455,6 +1437,8 @@ impl<'tcx> LateLintPass<'tcx> for TypeAliasBounds {
let mut where_spans = Vec::new();
let mut inline_spans = Vec::new();
let mut inline_sugg = Vec::new();
let mut affects_object_lifetime_defaults = false;
for p in generics.predicates {
let span = p.span();
if p.in_where_clause() {
@ -1465,31 +1449,61 @@ impl<'tcx> LateLintPass<'tcx> for TypeAliasBounds {
}
inline_sugg.push((span, String::new()));
}
// FIXME(fmease): Move this into a "diagnostic decorator" for increased laziness
// Bounds of the form `T: 'a` where `T` is a type param of
// the type alias affect object lifetime defaults.
if !affects_object_lifetime_defaults
&& let hir::WherePredicate::BoundPredicate(pred) = p
&& pred.bounds.iter().any(|bound| matches!(bound, hir::GenericBound::Outlives(_)))
&& pred.bound_generic_params.is_empty()
&& let hir::TyKind::Path(hir::QPath::Resolved(None, path)) = pred.bounded_ty.kind
&& let Res::Def(DefKind::TyParam, _) = path.res
{
affects_object_lifetime_defaults = true;
}
}
let mut suggested_changing_assoc_types = false;
if !where_spans.is_empty() {
let sub = (!suggested_changing_assoc_types).then(|| {
suggested_changing_assoc_types = true;
SuggestChangingAssocTypes { ty: hir_ty }
});
// FIXME(fmease): Add a disclaimer (in the form of a multi-span note) that the removal of
// type-param-outlives-bounds affects OLDs and explicit object lifetime
// bounds might be required [...].
// FIXME(fmease): The applicability should also depend on the outcome of the HIR walker
// inside of `TypeAliasBoundsQualifyAssocTysSugg`: Whether it found a
// shorthand projection or not.
let applicability = if affects_object_lifetime_defaults {
Applicability::MaybeIncorrect
} else {
Applicability::MachineApplicable
};
let mut qualify_assoc_tys_sugg = Some(TypeAliasBoundsQualifyAssocTysSugg { ty: hir_ty });
let enable_feat_help = cx.tcx.sess.is_nightly_build().then_some(());
if let [.., label_sp] = *where_spans {
cx.emit_span_lint(
TYPE_ALIAS_BOUNDS,
where_spans,
BuiltinTypeAliasWhereClause { suggestion: generics.where_clause_span, sub },
BuiltinTypeAliasBounds::WhereClause {
label: label_sp,
enable_feat_help,
suggestion: (generics.where_clause_span, applicability),
qualify_assoc_tys_sugg: qualify_assoc_tys_sugg.take(),
},
);
}
if !inline_spans.is_empty() {
let suggestion = BuiltinTypeAliasGenericBoundsSuggestion { suggestions: inline_sugg };
let sub = (!suggested_changing_assoc_types).then(|| {
suggested_changing_assoc_types = true;
SuggestChangingAssocTypes { ty: hir_ty }
});
if let [.., label_sp] = *inline_spans {
cx.emit_span_lint(
TYPE_ALIAS_BOUNDS,
inline_spans,
BuiltinTypeAliasGenericBounds { suggestion, sub },
BuiltinTypeAliasBounds::ParamBounds {
label: label_sp,
enable_feat_help,
suggestion: BuiltinTypeAliasParamBoundsSuggestion {
suggestions: inline_sugg,
applicability,
},
qualify_assoc_tys_sugg,
},
);
}
}

View file

@ -9,7 +9,7 @@ use rustc_errors::{
ElidedLifetimeInPathSubdiag, EmissionGuarantee, LintDiagnostic, MultiSpan, SubdiagMessageOp,
Subdiagnostic, SuggestionStyle,
};
use rustc_hir::{def::Namespace, def_id::DefId};
use rustc_hir::{self as hir, def::Namespace, def_id::DefId};
use rustc_macros::{LintDiagnostic, Subdiagnostic};
use rustc_middle::ty::{
inhabitedness::InhabitedPredicate, Clause, PolyExistentialTraitRef, Ty, TyCtxt,
@ -22,9 +22,7 @@ use rustc_span::{
Span, Symbol,
};
use crate::{
builtin::InitError, builtin::TypeAliasBounds, errors::OverruledAttributeSub, LateContext,
};
use crate::{builtin::InitError, errors::OverruledAttributeSub, LateContext};
// array_into_iter.rs
#[derive(LintDiagnostic)]
@ -263,62 +261,6 @@ pub struct BuiltinUnreachablePub<'a> {
pub help: Option<()>,
}
pub struct SuggestChangingAssocTypes<'a, 'b> {
pub ty: &'a rustc_hir::Ty<'b>,
}
impl<'a, 'b> Subdiagnostic for SuggestChangingAssocTypes<'a, 'b> {
fn add_to_diag_with<G: EmissionGuarantee, F: SubdiagMessageOp<G>>(
self,
diag: &mut Diag<'_, G>,
_f: &F,
) {
// Access to associates types should use `<T as Bound>::Assoc`, which does not need a
// bound. Let's see if this type does that.
// We use a HIR visitor to walk the type.
use rustc_hir::intravisit::{self, Visitor};
struct WalkAssocTypes<'a, 'b, G: EmissionGuarantee> {
err: &'a mut Diag<'b, G>,
}
impl<'a, 'b, G: EmissionGuarantee> Visitor<'_> for WalkAssocTypes<'a, 'b, G> {
fn visit_qpath(
&mut self,
qpath: &rustc_hir::QPath<'_>,
id: rustc_hir::HirId,
span: Span,
) {
if TypeAliasBounds::is_type_variable_assoc(qpath) {
self.err.span_help(span, fluent::lint_builtin_type_alias_bounds_help);
}
intravisit::walk_qpath(self, qpath, id)
}
}
// Let's go for a walk!
let mut visitor = WalkAssocTypes { err: diag };
visitor.visit_ty(self.ty);
}
}
#[derive(LintDiagnostic)]
#[diag(lint_builtin_type_alias_where_clause)]
pub struct BuiltinTypeAliasWhereClause<'a, 'b> {
#[suggestion(code = "", applicability = "machine-applicable")]
pub suggestion: Span,
#[subdiagnostic]
pub sub: Option<SuggestChangingAssocTypes<'a, 'b>>,
}
#[derive(LintDiagnostic)]
#[diag(lint_builtin_type_alias_generic_bounds)]
pub struct BuiltinTypeAliasGenericBounds<'a, 'b> {
#[subdiagnostic]
pub suggestion: BuiltinTypeAliasGenericBoundsSuggestion,
#[subdiagnostic]
pub sub: Option<SuggestChangingAssocTypes<'a, 'b>>,
}
#[derive(LintDiagnostic)]
#[diag(lint_macro_expr_fragment_specifier_2024_migration)]
pub struct MacroExprFragment2024 {
@ -326,21 +268,97 @@ pub struct MacroExprFragment2024 {
pub suggestion: Span,
}
pub struct BuiltinTypeAliasGenericBoundsSuggestion {
pub suggestions: Vec<(Span, String)>,
#[derive(LintDiagnostic)]
pub enum BuiltinTypeAliasBounds<'a, 'hir> {
#[diag(lint_builtin_type_alias_bounds_where_clause)]
#[note(lint_builtin_type_alias_bounds_limitation_note)]
WhereClause {
#[label(lint_builtin_type_alias_bounds_label)]
label: Span,
#[help(lint_builtin_type_alias_bounds_enable_feat_help)]
enable_feat_help: Option<()>,
#[suggestion(code = "")]
suggestion: (Span, Applicability),
#[subdiagnostic]
qualify_assoc_tys_sugg: Option<TypeAliasBoundsQualifyAssocTysSugg<'a, 'hir>>,
},
#[diag(lint_builtin_type_alias_bounds_param_bounds)]
#[note(lint_builtin_type_alias_bounds_limitation_note)]
ParamBounds {
#[label(lint_builtin_type_alias_bounds_label)]
label: Span,
#[help(lint_builtin_type_alias_bounds_enable_feat_help)]
enable_feat_help: Option<()>,
#[subdiagnostic]
suggestion: BuiltinTypeAliasParamBoundsSuggestion,
#[subdiagnostic]
qualify_assoc_tys_sugg: Option<TypeAliasBoundsQualifyAssocTysSugg<'a, 'hir>>,
},
}
impl Subdiagnostic for BuiltinTypeAliasGenericBoundsSuggestion {
pub struct BuiltinTypeAliasParamBoundsSuggestion {
pub suggestions: Vec<(Span, String)>,
pub applicability: Applicability,
}
impl Subdiagnostic for BuiltinTypeAliasParamBoundsSuggestion {
fn add_to_diag_with<G: EmissionGuarantee, F: SubdiagMessageOp<G>>(
self,
diag: &mut Diag<'_, G>,
_f: &F,
) {
diag.multipart_suggestion(
fluent::lint_suggestion,
self.suggestions,
Applicability::MachineApplicable,
);
diag.arg("count", self.suggestions.len());
diag.multipart_suggestion(fluent::lint_suggestion, self.suggestions, self.applicability);
}
}
pub struct TypeAliasBoundsQualifyAssocTysSugg<'a, 'hir> {
pub ty: &'a hir::Ty<'hir>,
}
impl<'a, 'hir> Subdiagnostic for TypeAliasBoundsQualifyAssocTysSugg<'a, 'hir> {
fn add_to_diag_with<G: EmissionGuarantee, F: SubdiagMessageOp<G>>(
self,
diag: &mut Diag<'_, G>,
_f: &F,
) {
// We perform the walk in here instead of in `<TypeAliasBounds as LateLintPass>` to
// avoid doing throwaway work in case the lint ends up getting suppressed.
use hir::intravisit::Visitor;
struct ProbeShorthandAssocTys<'a, 'b, G: EmissionGuarantee> {
diag: &'a mut Diag<'b, G>,
}
impl<'a, 'b, G: EmissionGuarantee> Visitor<'_> for ProbeShorthandAssocTys<'a, 'b, G> {
fn visit_qpath(&mut self, qpath: &hir::QPath<'_>, id: hir::HirId, _: Span) {
// Look for "type-parameter shorthand-associated-types". I.e., paths of the
// form `T::Assoc` with `T` type param. These are reliant on trait bounds.
// Suggest fully qualifying them via `<T as /* Trait */>::Assoc`.
//
// Instead of attempting to figure out the necessary trait ref, just use a
// placeholder. Since we don't record type-dependent resolutions for non-body
// items like type aliases, we can't simply deduce the corresp. trait from
// the HIR path alone without rerunning parts of HIR ty lowering here
// (namely `probe_single_ty_param_bound_for_assoc_ty`) which is infeasible.
//
// (We could employ some simple heuristics but that's likely not worth it).
if let hir::QPath::TypeRelative(qself, _) = qpath
&& let hir::TyKind::Path(hir::QPath::Resolved(None, path)) = qself.kind
&& let hir::def::Res::Def(hir::def::DefKind::TyParam, _) = path.res
{
self.diag.multipart_suggestion(
fluent::lint_builtin_type_alias_bounds_qualify_assoc_tys_sugg,
vec![
(qself.span.shrink_to_lo(), "<".into()),
(qself.span.shrink_to_hi(), " as /* Trait */>".into()),
],
Applicability::HasPlaceholders,
);
}
hir::intravisit::walk_qpath(self, qpath, id)
}
}
ProbeShorthandAssocTys { diag }.visit_ty(self.ty);
}
}

View file

@ -19,7 +19,7 @@
// automatically lead to full wfchecking and lint TAB getting suppressed.
pub type Alias<T: Bound> = (Source<T>::Assoc,);
//~^ WARN bounds on generic parameters are not enforced in type aliases
//~^ WARN bounds on generic parameters in type aliases are not enforced
pub struct Source<T>(T);
pub trait Bound {}

View file

@ -1,15 +1,16 @@
warning: bounds on generic parameters are not enforced in type aliases
warning: bounds on generic parameters in type aliases are not enforced
--> $DIR/type-alias-bounds.rs:21:19
|
LL | pub type Alias<T: Bound> = (Source<T>::Assoc,);
| ^^^^^
| --^^^^^
| | |
| | will not be checked at usage sites of the type alias
| help: remove this bound
|
= note: this is a known limitation of the type checker that may be lifted in a future edition.
see issue #112792 <https://github.com/rust-lang/rust/issues/112792> for more information
= help: add `#![feature(lazy_type_alias)]` to the crate attributes to enable the desired semantics
= note: `#[warn(type_alias_bounds)]` on by default
help: the bound will not be checked when the type alias is used, and should be removed
|
LL - pub type Alias<T: Bound> = (Source<T>::Assoc,);
LL + pub type Alias<T> = (Source<T>::Assoc,);
|
warning: 1 warning emitted

View file

@ -1,147 +1,159 @@
warning: where clauses are not enforced in type aliases
warning: where clauses on type aliases are not enforced
--> $DIR/type-alias.rs:3:25
|
LL | type _TaWhere1<T> where T: Iterator<Item: Copy> = T;
| ^^^^^^^^^^^^^^^^^^^^^^^
| ------^^^^^^^^^^^^^^^^^^^^^^^
| | |
| | will not be checked at usage sites of the type alias
| help: remove this where clause
|
= note: this is a known limitation of the type checker that may be lifted in a future edition.
see issue #112792 <https://github.com/rust-lang/rust/issues/112792> for more information
= help: add `#![feature(lazy_type_alias)]` to the crate attributes to enable the desired semantics
= note: `#[warn(type_alias_bounds)]` on by default
help: the clause will not be checked when the type alias is used, and should be removed
|
LL - type _TaWhere1<T> where T: Iterator<Item: Copy> = T;
LL + type _TaWhere1<T> = T;
|
warning: where clauses are not enforced in type aliases
warning: where clauses on type aliases are not enforced
--> $DIR/type-alias.rs:4:25
|
LL | type _TaWhere2<T> where T: Iterator<Item: 'static> = T;
| ^^^^^^^^^^^^^^^^^^^^^^^^^^
|
help: the clause will not be checked when the type alias is used, and should be removed
|
LL - type _TaWhere2<T> where T: Iterator<Item: 'static> = T;
LL + type _TaWhere2<T> = T;
| ------^^^^^^^^^^^^^^^^^^^^^^^^^^
| | |
| | will not be checked at usage sites of the type alias
| help: remove this where clause
|
= note: this is a known limitation of the type checker that may be lifted in a future edition.
see issue #112792 <https://github.com/rust-lang/rust/issues/112792> for more information
= help: add `#![feature(lazy_type_alias)]` to the crate attributes to enable the desired semantics
warning: where clauses are not enforced in type aliases
warning: where clauses on type aliases are not enforced
--> $DIR/type-alias.rs:5:25
|
LL | type _TaWhere3<T> where T: Iterator<Item: 'static> = T;
| ^^^^^^^^^^^^^^^^^^^^^^^^^^
|
help: the clause will not be checked when the type alias is used, and should be removed
|
LL - type _TaWhere3<T> where T: Iterator<Item: 'static> = T;
LL + type _TaWhere3<T> = T;
| ------^^^^^^^^^^^^^^^^^^^^^^^^^^
| | |
| | will not be checked at usage sites of the type alias
| help: remove this where clause
|
= note: this is a known limitation of the type checker that may be lifted in a future edition.
see issue #112792 <https://github.com/rust-lang/rust/issues/112792> for more information
= help: add `#![feature(lazy_type_alias)]` to the crate attributes to enable the desired semantics
warning: where clauses are not enforced in type aliases
warning: where clauses on type aliases are not enforced
--> $DIR/type-alias.rs:6:25
|
LL | type _TaWhere4<T> where T: Iterator<Item: 'static + Copy + Send> = T;
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
help: the clause will not be checked when the type alias is used, and should be removed
|
LL - type _TaWhere4<T> where T: Iterator<Item: 'static + Copy + Send> = T;
LL + type _TaWhere4<T> = T;
| ------^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
| | |
| | will not be checked at usage sites of the type alias
| help: remove this where clause
|
= note: this is a known limitation of the type checker that may be lifted in a future edition.
see issue #112792 <https://github.com/rust-lang/rust/issues/112792> for more information
= help: add `#![feature(lazy_type_alias)]` to the crate attributes to enable the desired semantics
warning: where clauses are not enforced in type aliases
warning: where clauses on type aliases are not enforced
--> $DIR/type-alias.rs:7:25
|
LL | type _TaWhere5<T> where T: Iterator<Item: for<'a> Into<&'a u8>> = T;
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
help: the clause will not be checked when the type alias is used, and should be removed
|
LL - type _TaWhere5<T> where T: Iterator<Item: for<'a> Into<&'a u8>> = T;
LL + type _TaWhere5<T> = T;
| ------^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
| | |
| | will not be checked at usage sites of the type alias
| help: remove this where clause
|
= note: this is a known limitation of the type checker that may be lifted in a future edition.
see issue #112792 <https://github.com/rust-lang/rust/issues/112792> for more information
= help: add `#![feature(lazy_type_alias)]` to the crate attributes to enable the desired semantics
warning: where clauses are not enforced in type aliases
warning: where clauses on type aliases are not enforced
--> $DIR/type-alias.rs:8:25
|
LL | type _TaWhere6<T> where T: Iterator<Item: Iterator<Item: Copy>> = T;
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
help: the clause will not be checked when the type alias is used, and should be removed
|
LL - type _TaWhere6<T> where T: Iterator<Item: Iterator<Item: Copy>> = T;
LL + type _TaWhere6<T> = T;
| ------^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
| | |
| | will not be checked at usage sites of the type alias
| help: remove this where clause
|
= note: this is a known limitation of the type checker that may be lifted in a future edition.
see issue #112792 <https://github.com/rust-lang/rust/issues/112792> for more information
= help: add `#![feature(lazy_type_alias)]` to the crate attributes to enable the desired semantics
warning: bounds on generic parameters are not enforced in type aliases
warning: bounds on generic parameters in type aliases are not enforced
--> $DIR/type-alias.rs:10:20
|
LL | type _TaInline1<T: Iterator<Item: Copy>> = T;
| ^^^^^^^^^^^^^^^^^^^^
|
help: the bound will not be checked when the type alias is used, and should be removed
|
LL - type _TaInline1<T: Iterator<Item: Copy>> = T;
LL + type _TaInline1<T> = T;
| --^^^^^^^^^^^^^^^^^^^^
| | |
| | will not be checked at usage sites of the type alias
| help: remove this bound
|
= note: this is a known limitation of the type checker that may be lifted in a future edition.
see issue #112792 <https://github.com/rust-lang/rust/issues/112792> for more information
= help: add `#![feature(lazy_type_alias)]` to the crate attributes to enable the desired semantics
warning: bounds on generic parameters are not enforced in type aliases
warning: bounds on generic parameters in type aliases are not enforced
--> $DIR/type-alias.rs:11:20
|
LL | type _TaInline2<T: Iterator<Item: 'static>> = T;
| ^^^^^^^^^^^^^^^^^^^^^^^
|
help: the bound will not be checked when the type alias is used, and should be removed
|
LL - type _TaInline2<T: Iterator<Item: 'static>> = T;
LL + type _TaInline2<T> = T;
| --^^^^^^^^^^^^^^^^^^^^^^^
| | |
| | will not be checked at usage sites of the type alias
| help: remove this bound
|
= note: this is a known limitation of the type checker that may be lifted in a future edition.
see issue #112792 <https://github.com/rust-lang/rust/issues/112792> for more information
= help: add `#![feature(lazy_type_alias)]` to the crate attributes to enable the desired semantics
warning: bounds on generic parameters are not enforced in type aliases
warning: bounds on generic parameters in type aliases are not enforced
--> $DIR/type-alias.rs:12:20
|
LL | type _TaInline3<T: Iterator<Item: 'static>> = T;
| ^^^^^^^^^^^^^^^^^^^^^^^
|
help: the bound will not be checked when the type alias is used, and should be removed
|
LL - type _TaInline3<T: Iterator<Item: 'static>> = T;
LL + type _TaInline3<T> = T;
| --^^^^^^^^^^^^^^^^^^^^^^^
| | |
| | will not be checked at usage sites of the type alias
| help: remove this bound
|
= note: this is a known limitation of the type checker that may be lifted in a future edition.
see issue #112792 <https://github.com/rust-lang/rust/issues/112792> for more information
= help: add `#![feature(lazy_type_alias)]` to the crate attributes to enable the desired semantics
warning: bounds on generic parameters are not enforced in type aliases
warning: bounds on generic parameters in type aliases are not enforced
--> $DIR/type-alias.rs:13:20
|
LL | type _TaInline4<T: Iterator<Item: 'static + Copy + Send>> = T;
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
help: the bound will not be checked when the type alias is used, and should be removed
|
LL - type _TaInline4<T: Iterator<Item: 'static + Copy + Send>> = T;
LL + type _TaInline4<T> = T;
| --^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
| | |
| | will not be checked at usage sites of the type alias
| help: remove this bound
|
= note: this is a known limitation of the type checker that may be lifted in a future edition.
see issue #112792 <https://github.com/rust-lang/rust/issues/112792> for more information
= help: add `#![feature(lazy_type_alias)]` to the crate attributes to enable the desired semantics
warning: bounds on generic parameters are not enforced in type aliases
warning: bounds on generic parameters in type aliases are not enforced
--> $DIR/type-alias.rs:14:20
|
LL | type _TaInline5<T: Iterator<Item: for<'a> Into<&'a u8>>> = T;
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
help: the bound will not be checked when the type alias is used, and should be removed
|
LL - type _TaInline5<T: Iterator<Item: for<'a> Into<&'a u8>>> = T;
LL + type _TaInline5<T> = T;
| --^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
| | |
| | will not be checked at usage sites of the type alias
| help: remove this bound
|
= note: this is a known limitation of the type checker that may be lifted in a future edition.
see issue #112792 <https://github.com/rust-lang/rust/issues/112792> for more information
= help: add `#![feature(lazy_type_alias)]` to the crate attributes to enable the desired semantics
warning: bounds on generic parameters are not enforced in type aliases
warning: bounds on generic parameters in type aliases are not enforced
--> $DIR/type-alias.rs:15:20
|
LL | type _TaInline6<T: Iterator<Item: Iterator<Item: Copy>>> = T;
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
help: the bound will not be checked when the type alias is used, and should be removed
|
LL - type _TaInline6<T: Iterator<Item: Iterator<Item: Copy>>> = T;
LL + type _TaInline6<T> = T;
| --^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
| | |
| | will not be checked at usage sites of the type alias
| help: remove this bound
|
= note: this is a known limitation of the type checker that may be lifted in a future edition.
see issue #112792 <https://github.com/rust-lang/rust/issues/112792> for more information
= help: add `#![feature(lazy_type_alias)]` to the crate attributes to enable the desired semantics
warning: 12 warnings emitted

View file

@ -39,7 +39,7 @@ mod traits {
pub trait PubTr {}
pub type Alias<T: PrivTr> = T; //~ ERROR trait `traits::PrivTr` is more private than the item `traits::Alias`
//~^ WARNING bounds on generic parameters are not enforced in type aliases
//~^ WARNING bounds on generic parameters in type aliases are not enforced
pub trait Tr1: PrivTr {} //~ ERROR trait `traits::PrivTr` is more private than the item `traits::Tr1`
pub trait Tr2<T: PrivTr> {} //~ ERROR trait `traits::PrivTr` is more private than the item `traits::Tr2`
pub trait Tr3 {
@ -58,7 +58,7 @@ mod traits_where {
pub type Alias<T> where T: PrivTr = T;
//~^ ERROR trait `traits_where::PrivTr` is more private than the item `traits_where::Alias`
//~| WARNING where clauses are not enforced in type aliases
//~| WARNING where clauses on type aliases are not enforced
pub trait Tr2<T> where T: PrivTr {}
//~^ ERROR trait `traits_where::PrivTr` is more private than the item `traits_where::Tr2`
pub trait Tr3 {

View file

@ -395,30 +395,32 @@ note: but type `Priv2` is only usable at visibility `pub(self)`
LL | struct Priv2;
| ^^^^^^^^^^^^
warning: bounds on generic parameters are not enforced in type aliases
warning: bounds on generic parameters in type aliases are not enforced
--> $DIR/private-in-public-warn.rs:41:23
|
LL | pub type Alias<T: PrivTr> = T;
| ^^^^^^
| --^^^^^^
| | |
| | will not be checked at usage sites of the type alias
| help: remove this bound
|
= note: this is a known limitation of the type checker that may be lifted in a future edition.
see issue #112792 <https://github.com/rust-lang/rust/issues/112792> for more information
= help: add `#![feature(lazy_type_alias)]` to the crate attributes to enable the desired semantics
= note: `#[warn(type_alias_bounds)]` on by default
help: the bound will not be checked when the type alias is used, and should be removed
|
LL - pub type Alias<T: PrivTr> = T;
LL + pub type Alias<T> = T;
|
warning: where clauses are not enforced in type aliases
warning: where clauses on type aliases are not enforced
--> $DIR/private-in-public-warn.rs:59:29
|
LL | pub type Alias<T> where T: PrivTr = T;
| ^^^^^^^^^
|
help: the clause will not be checked when the type alias is used, and should be removed
|
LL - pub type Alias<T> where T: PrivTr = T;
LL + pub type Alias<T> = T;
| ------^^^^^^^^^
| | |
| | will not be checked at usage sites of the type alias
| help: remove this where clause
|
= note: this is a known limitation of the type checker that may be lifted in a future edition.
see issue #112792 <https://github.com/rust-lang/rust/issues/112792> for more information
= help: add `#![feature(lazy_type_alias)]` to the crate attributes to enable the desired semantics
error: aborting due to 34 previous errors; 2 warnings emitted

View file

@ -24,18 +24,19 @@ warning: trait bound i32: Foo does not depend on any type or lifetime parameters
LL | union U where i32: Foo { f: i32 }
| ^^^
warning: where clauses are not enforced in type aliases
warning: where clauses on type aliases are not enforced
--> $DIR/trivial-bounds-inconsistent.rs:22:14
|
LL | type Y where i32: Foo = ();
| ^^^^^^^^
| ------^^^^^^^^
| | |
| | will not be checked at usage sites of the type alias
| help: remove this where clause
|
= note: this is a known limitation of the type checker that may be lifted in a future edition.
see issue #112792 <https://github.com/rust-lang/rust/issues/112792> for more information
= help: add `#![feature(lazy_type_alias)]` to the crate attributes to enable the desired semantics
= note: `#[warn(type_alias_bounds)]` on by default
help: the clause will not be checked when the type alias is used, and should be removed
|
LL - type Y where i32: Foo = ();
LL + type Y = ();
|
warning: trait bound i32: Foo does not depend on any type or lifetime parameters
--> $DIR/trivial-bounds-inconsistent.rs:22:19

View file

@ -3,6 +3,6 @@
//@ check-pass
pub type T<P: Send + Send + Send> = P;
//~^ WARN bounds on generic parameters are not enforced in type aliases
//~^ WARN bounds on generic parameters in type aliases are not enforced
fn main() {}

View file

@ -1,15 +1,16 @@
warning: bounds on generic parameters are not enforced in type aliases
warning: bounds on generic parameters in type aliases are not enforced
--> $DIR/issue-67690-type-alias-bound-diagnostic-crash.rs:5:15
|
LL | pub type T<P: Send + Send + Send> = P;
| ^^^^ ^^^^ ^^^^
| --^^^^---^^^^---^^^^
| | |
| | will not be checked at usage sites of the type alias
| help: remove this bound
|
= note: this is a known limitation of the type checker that may be lifted in a future edition.
see issue #112792 <https://github.com/rust-lang/rust/issues/112792> for more information
= help: add `#![feature(lazy_type_alias)]` to the crate attributes to enable the desired semantics
= note: `#[warn(type_alias_bounds)]` on by default
help: the bound will not be checked when the type alias is used, and should be removed
|
LL - pub type T<P: Send + Send + Send> = P;
LL + pub type T<P> = P;
|
warning: 1 warning emitted

View file

@ -6,15 +6,15 @@
use std::rc::Rc;
type SVec<T: Send + Send> = Vec<T>;
//~^ WARN bounds on generic parameters are not enforced in type aliases [type_alias_bounds]
//~^ WARN bounds on generic parameters in type aliases are not enforced [type_alias_bounds]
type S2Vec<T> where T: Send = Vec<T>;
//~^ WARN where clauses are not enforced in type aliases [type_alias_bounds]
//~^ WARN where clauses on type aliases are not enforced [type_alias_bounds]
type VVec<'b, 'a: 'b + 'b> = (&'b u32, Vec<&'a i32>);
//~^ WARN bounds on generic parameters are not enforced in type aliases [type_alias_bounds]
//~^ WARN bounds on generic parameters in type aliases are not enforced [type_alias_bounds]
type WVec<'b, T: 'b + 'b> = (&'b u32, Vec<T>);
//~^ WARN bounds on generic parameters are not enforced in type aliases [type_alias_bounds]
//~^ WARN bounds on generic parameters in type aliases are not enforced [type_alias_bounds]
type W2Vec<'b, T> where T: 'b, T: 'b = (&'b u32, Vec<T>);
//~^ WARN where clauses are not enforced in type aliases [type_alias_bounds]
//~^ WARN where clauses on type aliases are not enforced [type_alias_bounds]
static STATIC: u32 = 0;
@ -42,10 +42,11 @@ fn foo<'a>(y: &'a i32) {
struct Sendable<T: Send>(T);
type MySendable<T> = Sendable<T>; // no error here!
// However, bounds *are* taken into account when accessing associated types
// Bounds on type params do enable shorthand type alias paths.
// However, that doesn't actually mean that they are properly enforced.
trait Bound { type Assoc; }
type T1<U: Bound> = U::Assoc; //~ WARN not enforced in type aliases
type T2<U> where U: Bound = U::Assoc; //~ WARN not enforced in type aliases
type T1<U: Bound> = U::Assoc; //~ WARN are not enforced
type T2<U> where U: Bound = U::Assoc; //~ WARN are not enforced
// This errors:
// `type T3<U> = U::Assoc;`
@ -53,7 +54,7 @@ type T2<U> where U: Bound = U::Assoc; //~ WARN not enforced in type aliases
type T4<U> = <U as Bound>::Assoc;
// Make sure the help about associated types is not shown incorrectly
type T5<U: Bound> = <U as Bound>::Assoc; //~ WARN not enforced in type aliases
type T6<U: Bound> = ::std::vec::Vec<U>; //~ WARN not enforced in type aliases
type T5<U: Bound> = <U as Bound>::Assoc; //~ WARN are not enforced
type T6<U: Bound> = ::std::vec::Vec<U>; //~ WARN are not enforced
fn main() {}

View file

@ -1,121 +1,132 @@
warning: bounds on generic parameters are not enforced in type aliases
warning: bounds on generic parameters in type aliases are not enforced
--> $DIR/type-alias-bounds.rs:8:14
|
LL | type SVec<T: Send + Send> = Vec<T>;
| ^^^^ ^^^^
| --^^^^---^^^^
| | |
| | will not be checked at usage sites of the type alias
| help: remove this bound
|
= note: this is a known limitation of the type checker that may be lifted in a future edition.
see issue #112792 <https://github.com/rust-lang/rust/issues/112792> for more information
= help: add `#![feature(lazy_type_alias)]` to the crate attributes to enable the desired semantics
= note: `#[warn(type_alias_bounds)]` on by default
help: the bound will not be checked when the type alias is used, and should be removed
|
LL - type SVec<T: Send + Send> = Vec<T>;
LL + type SVec<T> = Vec<T>;
|
warning: where clauses are not enforced in type aliases
warning: where clauses on type aliases are not enforced
--> $DIR/type-alias-bounds.rs:10:21
|
LL | type S2Vec<T> where T: Send = Vec<T>;
| ^^^^^^^
|
help: the clause will not be checked when the type alias is used, and should be removed
|
LL - type S2Vec<T> where T: Send = Vec<T>;
LL + type S2Vec<T> = Vec<T>;
| ------^^^^^^^
| | |
| | will not be checked at usage sites of the type alias
| help: remove this where clause
|
= note: this is a known limitation of the type checker that may be lifted in a future edition.
see issue #112792 <https://github.com/rust-lang/rust/issues/112792> for more information
= help: add `#![feature(lazy_type_alias)]` to the crate attributes to enable the desired semantics
warning: bounds on generic parameters are not enforced in type aliases
warning: bounds on generic parameters in type aliases are not enforced
--> $DIR/type-alias-bounds.rs:12:19
|
LL | type VVec<'b, 'a: 'b + 'b> = (&'b u32, Vec<&'a i32>);
| ^^ ^^
|
help: the bound will not be checked when the type alias is used, and should be removed
|
LL - type VVec<'b, 'a: 'b + 'b> = (&'b u32, Vec<&'a i32>);
LL + type VVec<'b, 'a> = (&'b u32, Vec<&'a i32>);
| --^^---^^
| | |
| | will not be checked at usage sites of the type alias
| help: remove this bound
|
= note: this is a known limitation of the type checker that may be lifted in a future edition.
see issue #112792 <https://github.com/rust-lang/rust/issues/112792> for more information
= help: add `#![feature(lazy_type_alias)]` to the crate attributes to enable the desired semantics
warning: bounds on generic parameters are not enforced in type aliases
warning: bounds on generic parameters in type aliases are not enforced
--> $DIR/type-alias-bounds.rs:14:18
|
LL | type WVec<'b, T: 'b + 'b> = (&'b u32, Vec<T>);
| ^^ ^^
|
help: the bound will not be checked when the type alias is used, and should be removed
|
LL - type WVec<'b, T: 'b + 'b> = (&'b u32, Vec<T>);
LL + type WVec<'b, T> = (&'b u32, Vec<T>);
| --^^---^^
| | |
| | will not be checked at usage sites of the type alias
| help: remove this bound
|
= note: this is a known limitation of the type checker that may be lifted in a future edition.
see issue #112792 <https://github.com/rust-lang/rust/issues/112792> for more information
= help: add `#![feature(lazy_type_alias)]` to the crate attributes to enable the desired semantics
warning: where clauses are not enforced in type aliases
warning: where clauses on type aliases are not enforced
--> $DIR/type-alias-bounds.rs:16:25
|
LL | type W2Vec<'b, T> where T: 'b, T: 'b = (&'b u32, Vec<T>);
| ^^^^^ ^^^^^
|
help: the clause will not be checked when the type alias is used, and should be removed
|
LL - type W2Vec<'b, T> where T: 'b, T: 'b = (&'b u32, Vec<T>);
LL + type W2Vec<'b, T> = (&'b u32, Vec<T>);
| ------^^^^^--^^^^^
| | |
| | will not be checked at usage sites of the type alias
| help: remove this where clause
|
= note: this is a known limitation of the type checker that may be lifted in a future edition.
see issue #112792 <https://github.com/rust-lang/rust/issues/112792> for more information
= help: add `#![feature(lazy_type_alias)]` to the crate attributes to enable the desired semantics
warning: bounds on generic parameters are not enforced in type aliases
--> $DIR/type-alias-bounds.rs:47:12
warning: bounds on generic parameters in type aliases are not enforced
--> $DIR/type-alias-bounds.rs:48:12
|
LL | type T1<U: Bound> = U::Assoc;
| ^^^^^
| ^^^^^ will not be checked at usage sites of the type alias
|
help: use fully disambiguated paths (i.e., `<T as Trait>::Assoc`) to refer to associated types in type aliases
--> $DIR/type-alias-bounds.rs:47:21
|
LL | type T1<U: Bound> = U::Assoc;
| ^^^^^^^^
help: the bound will not be checked when the type alias is used, and should be removed
= note: this is a known limitation of the type checker that may be lifted in a future edition.
see issue #112792 <https://github.com/rust-lang/rust/issues/112792> for more information
= help: add `#![feature(lazy_type_alias)]` to the crate attributes to enable the desired semantics
help: remove this bound
|
LL - type T1<U: Bound> = U::Assoc;
LL + type T1<U> = U::Assoc;
|
help: fully qualify this associated type
|
LL | type T1<U: Bound> = <U as /* Trait */>::Assoc;
| + +++++++++++++++
warning: where clauses are not enforced in type aliases
--> $DIR/type-alias-bounds.rs:48:18
warning: where clauses on type aliases are not enforced
--> $DIR/type-alias-bounds.rs:49:18
|
LL | type T2<U> where U: Bound = U::Assoc;
| ^^^^^^^^
| ^^^^^^^^ will not be checked at usage sites of the type alias
|
help: use fully disambiguated paths (i.e., `<T as Trait>::Assoc`) to refer to associated types in type aliases
--> $DIR/type-alias-bounds.rs:48:29
|
LL | type T2<U> where U: Bound = U::Assoc;
| ^^^^^^^^
help: the clause will not be checked when the type alias is used, and should be removed
= note: this is a known limitation of the type checker that may be lifted in a future edition.
see issue #112792 <https://github.com/rust-lang/rust/issues/112792> for more information
= help: add `#![feature(lazy_type_alias)]` to the crate attributes to enable the desired semantics
help: remove this where clause
|
LL - type T2<U> where U: Bound = U::Assoc;
LL + type T2<U> = U::Assoc;
|
help: fully qualify this associated type
|
LL | type T2<U> where U: Bound = <U as /* Trait */>::Assoc;
| + +++++++++++++++
warning: bounds on generic parameters are not enforced in type aliases
--> $DIR/type-alias-bounds.rs:56:12
|
LL | type T5<U: Bound> = <U as Bound>::Assoc;
| ^^^^^
|
help: the bound will not be checked when the type alias is used, and should be removed
|
LL - type T5<U: Bound> = <U as Bound>::Assoc;
LL + type T5<U> = <U as Bound>::Assoc;
|
warning: bounds on generic parameters are not enforced in type aliases
warning: bounds on generic parameters in type aliases are not enforced
--> $DIR/type-alias-bounds.rs:57:12
|
LL | type T5<U: Bound> = <U as Bound>::Assoc;
| --^^^^^
| | |
| | will not be checked at usage sites of the type alias
| help: remove this bound
|
= note: this is a known limitation of the type checker that may be lifted in a future edition.
see issue #112792 <https://github.com/rust-lang/rust/issues/112792> for more information
= help: add `#![feature(lazy_type_alias)]` to the crate attributes to enable the desired semantics
warning: bounds on generic parameters in type aliases are not enforced
--> $DIR/type-alias-bounds.rs:58:12
|
LL | type T6<U: Bound> = ::std::vec::Vec<U>;
| ^^^^^
|
help: the bound will not be checked when the type alias is used, and should be removed
|
LL - type T6<U: Bound> = ::std::vec::Vec<U>;
LL + type T6<U> = ::std::vec::Vec<U>;
| --^^^^^
| | |
| | will not be checked at usage sites of the type alias
| help: remove this bound
|
= note: this is a known limitation of the type checker that may be lifted in a future edition.
see issue #112792 <https://github.com/rust-lang/rust/issues/112792> for more information
= help: add `#![feature(lazy_type_alias)]` to the crate attributes to enable the desired semantics
warning: 9 warnings emitted