mikros/rust
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Use ControlFlow in HIR visitors

Browse Source
This commit is contained in:
Jason Newcomb 2024-02-24 02:53:05 -05:00
parent e760c44063
commit 822b10d428
12 changed files with 170 additions and 203 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

76
compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs
View File

@ -1,6 +1,7 @@
#![allow(rustc::diagnostic_outside_of_impl)]
#![allow(rustc::untranslatable_diagnostic)]
use core::ops::ControlFlow;
use hir::ExprKind;
use rustc_errors::{Applicability, Diag};
use rustc_hir as hir;
@ -727,30 +728,12 @@ fn construct_mut_suggestion_for_local_binding_patterns(
_ => local_decl.source_info.span,
};
struct BindingFinder {
span: Span,
hir_id: Option<hir::HirId>,
}
impl<'tcx> Visitor<'tcx> for BindingFinder {
fn visit_stmt(&mut self, s: &'tcx hir::Stmt<'tcx>) {
if let hir::StmtKind::Local(local) = s.kind {
if local.pat.span == self.span {
self.hir_id = Some(local.hir_id);
}
}
hir::intravisit::walk_stmt(self, s);
}
}
let def_id = self.body.source.def_id();
let hir_id = if let Some(local_def_id) = def_id.as_local()
&& let Some(body_id) = self.infcx.tcx.hir().maybe_body_owned_by(local_def_id)
{
let body = self.infcx.tcx.hir().body(body_id);
let mut v = BindingFinder { span: pat_span, hir_id: None };
v.visit_body(body);
v.hir_id
BindingFinder { span: pat_span }.visit_body(body).break_value()
} else {
None
};
@ -859,17 +842,18 @@ fn suggest_similar_mut_method_for_for_loop(&self, err: &mut Diag<'_>, span: Span
};
let hir_map = self.infcx.tcx.hir();
struct Finder<'tcx> {
struct Finder {
span: Span,
expr: Option<&'tcx Expr<'tcx>>,
}
impl<'tcx> Visitor<'tcx> for Finder<'tcx> {
fn visit_expr(&mut self, e: &'tcx hir::Expr<'tcx>) {
if e.span == self.span && self.expr.is_none() {
self.expr = Some(e);
impl<'tcx> Visitor<'tcx> for Finder {
type Result = ControlFlow<&'tcx Expr<'tcx>>;
fn visit_expr(&mut self, e: &'tcx hir::Expr<'tcx>) -> Self::Result {
if e.span == self.span {
ControlFlow::Break(e)
} else {
hir::intravisit::walk_expr(self, e)
}
hir::intravisit::walk_expr(self, e);
}
}
if let Some(body_id) = hir_map.maybe_body_owned_by(self.mir_def_id())
@ -878,9 +862,7 @@ fn visit_expr(&mut self, e: &'tcx hir::Expr<'tcx>) {
// `span` corresponds to the expression being iterated, find the `for`-loop desugared
// expression with that span in order to identify potential fixes when encountering a
// read-only iterator that should be mutable.
let mut v = Finder { span, expr: None };
v.visit_block(block);
if let Some(expr) = v.expr
if let ControlFlow::Break(expr) = (Finder { span }).visit_block(block)
&& let Call(_, [expr]) = expr.kind
{
match expr.kind {
@ -1179,29 +1161,12 @@ fn suggest_make_local_mut(&self, err: &mut Diag<'_>, local: Local, name: Symbol)
);
}
Some((false, err_label_span, message)) => {
struct BindingFinder {
span: Span,
hir_id: Option<hir::HirId>,
}
impl<'tcx> Visitor<'tcx> for BindingFinder {
fn visit_stmt(&mut self, s: &'tcx hir::Stmt<'tcx>) {
if let hir::StmtKind::Local(local) = s.kind {
if local.pat.span == self.span {
self.hir_id = Some(local.hir_id);
}
}
hir::intravisit::walk_stmt(self, s);
}
}
let def_id = self.body.source.def_id();
let hir_id = if let Some(local_def_id) = def_id.as_local()
&& let Some(body_id) = self.infcx.tcx.hir().maybe_body_owned_by(local_def_id)
{
let body = self.infcx.tcx.hir().body(body_id);
let mut v = BindingFinder { span: err_label_span, hir_id: None };
v.visit_body(body);
v.hir_id
BindingFinder { span: err_label_span }.visit_body(body).break_value()
} else {
None
};
@ -1333,6 +1298,23 @@ fn visit_stmt(&mut self, s: &'tcx hir::Stmt<'tcx>) {
}
}
struct BindingFinder {
span: Span,
}
impl<'tcx> Visitor<'tcx> for BindingFinder {
type Result = ControlFlow<hir::HirId>;
fn visit_stmt(&mut self, s: &'tcx hir::Stmt<'tcx>) -> Self::Result {
if let hir::StmtKind::Local(local) = s.kind
&& local.pat.span == self.span
{
ControlFlow::Break(local.hir_id)
} else {
hir::intravisit::walk_stmt(self, s)
}
}
}
pub fn mut_borrow_of_mutable_ref(local_decl: &LocalDecl<'_>, local_name: Option<Symbol>) -> bool {
debug!("local_info: {:?}, ty.kind(): {:?}", local_decl.local_info, local_decl.ty.kind());

1
compiler/rustc_borrowck/src/lib.rs
View File

@ -6,6 +6,7 @@
#![feature(assert_matches)]
#![feature(associated_type_bounds)]
#![feature(box_patterns)]
#![feature(control_flow_enum)]
#![feature(let_chains)]
#![feature(min_specialization)]
#![feature(never_type)]

21
compiler/rustc_hir_analysis/src/check/compare_impl_item.rs
View File

@ -1,5 +1,6 @@
use super::potentially_plural_count;
use crate::errors::{LifetimesOrBoundsMismatchOnTrait, MethodShouldReturnFuture};
use core::ops::ControlFlow;
use hir::def_id::{DefId, DefIdMap, LocalDefId};
use rustc_data_structures::fx::{FxHashSet, FxIndexMap, FxIndexSet};
use rustc_errors::{codes::*, pluralize, struct_span_code_err, Applicability, ErrorGuaranteed};
@ -1565,24 +1566,24 @@ fn compare_synthetic_generics<'tcx>(
let (sig, _) = impl_m.expect_fn();
let input_tys = sig.decl.inputs;
struct Visitor(Option<Span>, hir::def_id::LocalDefId);
struct Visitor(hir::def_id::LocalDefId);
impl<'v> intravisit::Visitor<'v> for Visitor {
fn visit_ty(&mut self, ty: &'v hir::Ty<'v>) {
intravisit::walk_ty(self, ty);
type Result = ControlFlow<Span>;
fn visit_ty(&mut self, ty: &'v hir::Ty<'v>) -> Self::Result {
if let hir::TyKind::Path(hir::QPath::Resolved(None, path)) = ty.kind
&& let Res::Def(DefKind::TyParam, def_id) = path.res
&& def_id == self.1.to_def_id()
&& def_id == self.0.to_def_id()
{
self.0 = Some(ty.span);
ControlFlow::Break(ty.span)
} else {
intravisit::walk_ty(self, ty)
}
}
}
let mut visitor = Visitor(None, impl_def_id);
for ty in input_tys {
intravisit::Visitor::visit_ty(&mut visitor, ty);
}
let span = visitor.0?;
let span = input_tys.iter().find_map(|ty| {
intravisit::Visitor::visit_ty(&mut Visitor(impl_def_id), ty).break_value()
})?;
let bounds = impl_m.generics.bounds_for_param(impl_def_id).next()?.bounds;
let bounds = bounds.first()?.span().to(bounds.last()?.span());

22
compiler/rustc_hir_analysis/src/collect/resolve_bound_vars.rs
View File

@ -6,6 +6,7 @@
//! the types in HIR to identify late-bound lifetimes and assign their Debruijn indices. This file
//! is also responsible for assigning their semantics to implicit lifetimes in trait objects.
use core::ops::ControlFlow;
use rustc_ast::visit::walk_list;
use rustc_data_structures::fx::{FxHashSet, FxIndexMap, FxIndexSet};
use rustc_errors::{codes::*, struct_span_code_err};
@ -417,23 +418,18 @@ fn visit_expr(&mut self, e: &'tcx hir::Expr<'tcx>) {
{
if let &hir::ClosureBinder::For { span: for_sp, .. } = binder {
fn span_of_infer(ty: &hir::Ty<'_>) -> Option<Span> {
struct V(Option<Span>);
struct V;
impl<'v> Visitor<'v> for V {
fn visit_ty(&mut self, t: &'v hir::Ty<'v>) {
match t.kind {
_ if self.0.is_some() => (),
hir::TyKind::Infer => {
self.0 = Some(t.span);
}
_ => intravisit::walk_ty(self, t),
type Result = ControlFlow<Span>;
fn visit_ty(&mut self, t: &'v hir::Ty<'v>) -> Self::Result {
if matches!(t.kind, hir::TyKind::Infer) {
ControlFlow::Break(t.span)
} else {
intravisit::walk_ty(self, t)
}
}
}
let mut v = V(None);
v.visit_ty(ty);
v.0
V.visit_ty(ty).break_value()
}
let infer_in_rt_sp = match fn_decl.output {

16
compiler/rustc_hir_analysis/src/collect/type_of.rs
View File

@ -1,3 +1,4 @@
use core::ops::ControlFlow;
use rustc_errors::{Applicability, StashKey};
use rustc_hir as hir;
use rustc_hir::def_id::{DefId, LocalDefId};
@ -666,19 +667,16 @@ pub fn type_alias_is_lazy<'tcx>(tcx: TyCtxt<'tcx>, def_id: LocalDefId) -> bool {
if tcx.features().lazy_type_alias {
return true;
}
struct HasTait {
has_type_alias_impl_trait: bool,
}
struct HasTait;
impl<'tcx> Visitor<'tcx> for HasTait {
fn visit_ty(&mut self, t: &'tcx hir::Ty<'tcx>) {
type Result = ControlFlow<()>;
fn visit_ty(&mut self, t: &'tcx hir::Ty<'tcx>) -> Self::Result {
if let hir::TyKind::OpaqueDef(..) = t.kind {
self.has_type_alias_impl_trait = true;
ControlFlow::Break(())
} else {
hir::intravisit::walk_ty(self, t);
hir::intravisit::walk_ty(self, t)
}
}
}
let mut has_tait = HasTait { has_type_alias_impl_trait: false };
has_tait.visit_ty(tcx.hir().expect_item(def_id).expect_ty_alias().0);
has_tait.has_type_alias_impl_trait
HasTait.visit_ty(tcx.hir().expect_item(def_id).expect_ty_alias().0).is_break()
}

21
compiler/rustc_hir_typeck/src/method/suggest.rs
View File

@ -6,6 +6,7 @@
use crate::errors::{self, CandidateTraitNote, NoAssociatedItem};
use crate::Expectation;
use crate::FnCtxt;
use core::ops::ControlFlow;
use rustc_ast::ast::Mutability;
use rustc_attr::parse_confusables;
use rustc_data_structures::fx::{FxIndexMap, FxIndexSet};
@ -2212,30 +2213,28 @@ pub(crate) fn suggest_assoc_method_call(&self, segs: &[PathSegment<'_>]) {
let map = self.infcx.tcx.hir();
let body_id = self.tcx.hir().body_owned_by(self.body_id);
let body = map.body(body_id);
struct LetVisitor<'a> {
result: Option<&'a hir::Expr<'a>>,
struct LetVisitor {
ident_name: Symbol,
}
// FIXME: This really should be taking scoping, etc into account.
impl<'v> Visitor<'v> for LetVisitor<'v> {
fn visit_stmt(&mut self, ex: &'v hir::Stmt<'v>) {
if let hir::StmtKind::Local(hir::Local { pat, init, .. }) = &ex.kind
impl<'v> Visitor<'v> for LetVisitor {
type Result = ControlFlow<Option<&'v hir::Expr<'v>>>;
fn visit_stmt(&mut self, ex: &'v hir::Stmt<'v>) -> Self::Result {
if let hir::StmtKind::Local(&hir::Local { pat, init, .. }) = ex.kind
&& let Binding(_, _, ident, ..) = pat.kind
&& ident.name == self.ident_name
{
self.result = *init;
ControlFlow::Break(init)
} else {
hir::intravisit::walk_stmt(self, ex);
hir::intravisit::walk_stmt(self, ex)
}
}
}
let mut visitor = LetVisitor { result: None, ident_name: seg1.ident.name };
visitor.visit_body(body);
if let Node::Expr(call_expr) = self.tcx.parent_hir_node(seg1.hir_id)
&& let Some(expr) = visitor.result
&& let ControlFlow::Break(Some(expr)) =
(LetVisitor { ident_name: seg1.ident.name }).visit_body(body)
&& let Some(self_ty) = self.node_ty_opt(expr.hir_id)
{
let probe = self.lookup_probe_for_diagnostic(

21
compiler/rustc_infer/src/infer/error_reporting/mod.rs
View File

@ -79,7 +79,7 @@
use rustc_span::{sym, symbol::kw, BytePos, DesugaringKind, Pos, Span};
use rustc_target::spec::abi;
use std::borrow::Cow;
use std::ops::Deref;
use std::ops::{ControlFlow, Deref};
use std::path::PathBuf;
use std::{cmp, fmt, iter};
@ -2129,15 +2129,12 @@ fn suggest_specify_actual_length(
let tykind = match self.tcx.opt_hir_node_by_def_id(trace.cause.body_id) {
Some(hir::Node::Item(hir::Item { kind: hir::ItemKind::Fn(_, _, body_id), .. })) => {
let body = hir.body(*body_id);
struct LetVisitor<'v> {
struct LetVisitor {
span: Span,
result: Option<&'v hir::Ty<'v>>,
}
impl<'v> Visitor<'v> for LetVisitor<'v> {
fn visit_stmt(&mut self, s: &'v hir::Stmt<'v>) {
if self.result.is_some() {
return;
}
impl<'v> Visitor<'v> for LetVisitor {
type Result = ControlFlow<&'v hir::TyKind<'v>>;
fn visit_stmt(&mut self, s: &'v hir::Stmt<'v>) -> Self::Result {
// Find a local statement where the initializer has
// the same span as the error and the type is specified.
if let hir::Stmt {
@ -2151,13 +2148,13 @@ fn visit_stmt(&mut self, s: &'v hir::Stmt<'v>) {
} = s
&& init_span == &self.span
{
self.result = Some(*array_ty);
ControlFlow::Break(&array_ty.peel_refs().kind)
} else {
ControlFlow::Continue(())
}
}
}
let mut visitor = LetVisitor { span, result: None };
visitor.visit_body(body);
visitor.result.map(|r| &r.peel_refs().kind)
LetVisitor { span }.visit_body(body).break_value()
}
Some(hir::Node::Item(hir::Item { kind: hir::ItemKind::Const(ty, _, _), .. })) => {
Some(&ty.peel_refs().kind)

69
compiler/rustc_infer/src/infer/error_reporting/nice_region_error/find_anon_type.rs
View File

@ -1,3 +1,4 @@
use core::ops::ControlFlow;
use rustc_hir as hir;
use rustc_hir::intravisit::{self, Visitor};
use rustc_middle::hir::map::Map;
@ -43,14 +44,9 @@ fn find_component_for_bound_region<'tcx>(
arg: &'tcx hir::Ty<'tcx>,
br: &ty::BoundRegionKind,
) -> Option<&'tcx hir::Ty<'tcx>> {
let mut nested_visitor = FindNestedTypeVisitor {
tcx,
bound_region: *br,
found_type: None,
current_index: ty::INNERMOST,
};
nested_visitor.visit_ty(arg);
nested_visitor.found_type
FindNestedTypeVisitor { tcx, bound_region: *br, current_index: ty::INNERMOST }
.visit_ty(arg)
.break_value()
}
// The FindNestedTypeVisitor captures the corresponding `hir::Ty` of the
@ -65,26 +61,24 @@ struct FindNestedTypeVisitor<'tcx> {
// The bound_region corresponding to the Refree(freeregion)
// associated with the anonymous region we are looking for.
bound_region: ty::BoundRegionKind,
// The type where the anonymous lifetime appears
// for e.g., Vec<`&u8`> and <`&u8`>
found_type: Option<&'tcx hir::Ty<'tcx>>,
current_index: ty::DebruijnIndex,
}
impl<'tcx> Visitor<'tcx> for FindNestedTypeVisitor<'tcx> {
type Result = ControlFlow<&'tcx hir::Ty<'tcx>>;
type NestedFilter = nested_filter::OnlyBodies;
fn nested_visit_map(&mut self) -> Self::Map {
self.tcx.hir()
}
fn visit_ty(&mut self, arg: &'tcx hir::Ty<'tcx>) {
fn visit_ty(&mut self, arg: &'tcx hir::Ty<'tcx>) -> Self::Result {
match arg.kind {
hir::TyKind::BareFn(_) => {
self.current_index.shift_in(1);
intravisit::walk_ty(self, arg);
self.current_index.shift_out(1);
return;
return ControlFlow::Continue(());
}
hir::TyKind::TraitObject(bounds, ..) => {
@ -105,8 +99,7 @@ fn visit_ty(&mut self, arg: &'tcx hir::Ty<'tcx>) {
(Some(rbv::ResolvedArg::EarlyBound(id)), ty::BrNamed(def_id, _)) => {
debug!("EarlyBound id={:?} def_id={:?}", id, def_id);
if id == def_id {
self.found_type = Some(arg);
return; // we can stop visiting now
return ControlFlow::Break(arg);
}
}
@ -123,8 +116,7 @@ fn visit_ty(&mut self, arg: &'tcx hir::Ty<'tcx>) {
);
debug!("LateBound id={:?} def_id={:?}", id, def_id);
if debruijn_index == self.current_index && id == def_id {
self.found_type = Some(arg);
return; // we can stop visiting now
return ControlFlow::Break(arg);
}
}
@ -145,23 +137,30 @@ fn visit_ty(&mut self, arg: &'tcx hir::Ty<'tcx>) {
}
// Checks if it is of type `hir::TyKind::Path` which corresponds to a struct.
hir::TyKind::Path(_) => {
let subvisitor = &mut TyPathVisitor {
tcx: self.tcx,
found_it: false,
bound_region: self.bound_region,
current_index: self.current_index,
// Prefer using the lifetime in type arguments rather than lifetime arguments.
intravisit::walk_ty(self, arg)?;
// Call `walk_ty` as `visit_ty` is empty.
return if intravisit::walk_ty(
&mut TyPathVisitor {
tcx: self.tcx,
bound_region: self.bound_region,
current_index: self.current_index,
},
arg,
)
.is_break()
{
ControlFlow::Break(arg)
} else {
ControlFlow::Continue(())
};
intravisit::walk_ty(subvisitor, arg); // call walk_ty; as visit_ty is empty,
// this will visit only outermost type
if subvisitor.found_it {
self.found_type = Some(arg);
}
}
_ => {}
}
// walk the embedded contents: e.g., if we are visiting `Vec<&Foo>`,
// go on to visit `&Foo`
intravisit::walk_ty(self, arg);
intravisit::walk_ty(self, arg)
}
}
@ -173,26 +172,25 @@ fn visit_ty(&mut self, arg: &'tcx hir::Ty<'tcx>) {
// specific part of the type in the error message.
struct TyPathVisitor<'tcx> {
tcx: TyCtxt<'tcx>,
found_it: bool,
bound_region: ty::BoundRegionKind,
current_index: ty::DebruijnIndex,
}
impl<'tcx> Visitor<'tcx> for TyPathVisitor<'tcx> {
type Result = ControlFlow<()>;
type NestedFilter = nested_filter::OnlyBodies;
fn nested_visit_map(&mut self) -> Map<'tcx> {
self.tcx.hir()
}
fn visit_lifetime(&mut self, lifetime: &hir::Lifetime) {
fn visit_lifetime(&mut self, lifetime: &hir::Lifetime) -> Self::Result {
match (self.tcx.named_bound_var(lifetime.hir_id), self.bound_region) {
// the lifetime of the TyPath!
(Some(rbv::ResolvedArg::EarlyBound(id)), ty::BrNamed(def_id, _)) => {
debug!("EarlyBound id={:?} def_id={:?}", id, def_id);
if id == def_id {
self.found_it = true;
return; // we can stop visiting now
return ControlFlow::Break(());
}
}
@ -201,8 +199,7 @@ fn visit_lifetime(&mut self, lifetime: &hir::Lifetime) {
debug!("id={:?}", id);
debug!("def_id={:?}", def_id);
if debruijn_index == self.current_index && id == def_id {
self.found_it = true;
return; // we can stop visiting now
return ControlFlow::Break(());
}
}
@ -220,9 +217,10 @@ fn visit_lifetime(&mut self, lifetime: &hir::Lifetime) {
debug!("no arg found");
}
}
ControlFlow::Continue(())
}
fn visit_ty(&mut self, arg: &'tcx hir::Ty<'tcx>) {
fn visit_ty(&mut self, arg: &'tcx hir::Ty<'tcx>) -> Self::Result {
// ignore nested types
//
// If you have a type like `Foo<'a, &Ty>` we
@ -231,5 +229,6 @@ fn visit_ty(&mut self, arg: &'tcx hir::Ty<'tcx>) {
// Making `visit_ty` empty will ignore the `&Ty` embedded
// inside, it will get reached by the outer visitor.
debug!("`Ty` corresponding to a struct is {:?}", arg);
ControlFlow::Continue(())
}
}

92
compiler/rustc_infer/src/infer/error_reporting/suggest.rs
View File

@ -1,4 +1,5 @@
use crate::infer::error_reporting::hir::Path;
use core::ops::ControlFlow;
use hir::def::CtorKind;
use hir::intravisit::{walk_expr, walk_stmt, Visitor};
use hir::{Local, QPath};
@ -563,62 +564,55 @@ pub(super) fn suggest_let_for_letchains(
cause: &ObligationCause<'_>,
span: Span,
) -> Option<TypeErrorAdditionalDiags> {
let hir = self.tcx.hir();
if let Some(body_id) = self.tcx.hir().maybe_body_owned_by(cause.body_id) {
let body = hir.body(body_id);
/// Find the if expression with given span
struct IfVisitor {
pub found_if: bool,
pub err_span: Span,
}
/// Find the if expression with given span
struct IfVisitor {
pub result: bool,
pub found_if: bool,
pub err_span: Span,
}
impl<'v> Visitor<'v> for IfVisitor {
fn visit_expr(&mut self, ex: &'v hir::Expr<'v>) {
if self.result {
return;
impl<'v> Visitor<'v> for IfVisitor {
type Result = ControlFlow<()>;
fn visit_expr(&mut self, ex: &'v hir::Expr<'v>) -> Self::Result {
match ex.kind {
hir::ExprKind::If(cond, _, _) => {
self.found_if = true;
walk_expr(self, cond)?;
self.found_if = false;
ControlFlow::Continue(())
}
match ex.kind {
hir::ExprKind::If(cond, _, _) => {
self.found_if = true;
walk_expr(self, cond);
self.found_if = false;
}
_ => walk_expr(self, ex),
}
}
fn visit_stmt(&mut self, ex: &'v hir::Stmt<'v>) {
if let hir::StmtKind::Local(hir::Local {
span,
pat: hir::Pat { .. },
ty: None,
init: Some(_),
..
}) = &ex.kind
&& self.found_if
&& span.eq(&self.err_span)
{
self.result = true;
}
walk_stmt(self, ex);
}
fn visit_body(&mut self, body: &'v hir::Body<'v>) {
hir::intravisit::walk_body(self, body);
_ => walk_expr(self, ex),
}
}
let mut visitor = IfVisitor { err_span: span, found_if: false, result: false };
visitor.visit_body(body);
if visitor.result {
return Some(TypeErrorAdditionalDiags::AddLetForLetChains {
span: span.shrink_to_lo(),
});
fn visit_stmt(&mut self, ex: &'v hir::Stmt<'v>) -> Self::Result {
if let hir::StmtKind::Local(hir::Local {
span,
pat: hir::Pat { .. },
ty: None,
init: Some(_),
..
}) = &ex.kind
&& self.found_if
&& span.eq(&self.err_span)
{
ControlFlow::Break(())
} else {
walk_stmt(self, ex)
}
}
fn visit_body(&mut self, body: &'v hir::Body<'v>) -> Self::Result {
hir::intravisit::walk_body(self, body)
}
}
None
self.tcx.hir().maybe_body_owned_by(cause.body_id).and_then(|body_id| {
let body = self.tcx.hir().body(body_id);
IfVisitor { err_span: span, found_if: false }
.visit_body(body)
.is_break()
.then(|| TypeErrorAdditionalDiags::AddLetForLetChains { span: span.shrink_to_lo() })
})
}
/// For "one type is more general than the other" errors on closures, suggest changing the lifetime

1
compiler/rustc_infer/src/lib.rs
View File

@ -20,6 +20,7 @@
#![allow(rustc::untranslatable_diagnostic)]
#![feature(associated_type_bounds)]
#![feature(box_patterns)]
#![feature(control_flow_enum)]
#![feature(extend_one)]
#![feature(let_chains)]
#![feature(if_let_guard)]

27
compiler/rustc_trait_selection/src/traits/error_reporting/type_err_ctxt_ext.rs
View File

@ -19,6 +19,7 @@
ObligationCause, ObligationCauseCode, ObligationCtxt, Overflow, PredicateObligation,
SelectionError, SignatureMismatch, TraitNotObjectSafe,
};
use core::ops::ControlFlow;
use rustc_data_structures::fx::{FxHashMap, FxIndexMap};
use rustc_errors::codes::*;
use rustc_errors::{pluralize, struct_span_code_err, Applicability, MultiSpan, StringPart};
@ -1126,22 +1127,20 @@ fn try_conversion_context(
err: &mut Diag<'_>,
) -> bool {
let span = obligation.cause.span;
struct V<'v> {
struct V {
search_span: Span,
found: Option<&'v hir::Expr<'v>>,
}
impl<'v> Visitor<'v> for V<'v> {
fn visit_expr(&mut self, ex: &'v hir::Expr<'v>) {
impl<'v> Visitor<'v> for V {
type Result = ControlFlow<&'v hir::Expr<'v>>;
fn visit_expr(&mut self, ex: &'v hir::Expr<'v>) -> Self::Result {
if let hir::ExprKind::Match(expr, _arms, hir::MatchSource::TryDesugar(_)) = ex.kind
&& ex.span.with_lo(ex.span.hi() - BytePos(1)).source_equal(self.search_span)
&& let hir::ExprKind::Call(_, [expr, ..]) = expr.kind
{
if ex.span.with_lo(ex.span.hi() - BytePos(1)).source_equal(self.search_span) {
if let hir::ExprKind::Call(_, [expr, ..]) = expr.kind {
self.found = Some(expr);
return;
}
}
ControlFlow::Break(expr)
} else {
hir::intravisit::walk_expr(self, ex)
}
hir::intravisit::walk_expr(self, ex);
}
}
let hir_id = self.tcx.local_def_id_to_hir_id(obligation.cause.body_id);
@ -1149,9 +1148,9 @@ fn visit_expr(&mut self, ex: &'v hir::Expr<'v>) {
hir::Node::Item(hir::Item { kind: hir::ItemKind::Fn(_, _, body_id), .. }) => body_id,
_ => return false,
};
let mut v = V { search_span: span, found: None };
v.visit_body(self.tcx.hir().body(*body_id));
let Some(expr) = v.found else {
let ControlFlow::Break(expr) =
(V { search_span: span }).visit_body(self.tcx.hir().body(*body_id))
else {
return false;
};
let Some(typeck) = &self.typeck_results else {

6
tests/ui/issues/issue-20831-debruijn.stderr
View File

@ -4,11 +4,11 @@ error[E0495]: cannot infer an appropriate lifetime for lifetime parameter `'a` d
LL | fn subscribe(&mut self, t : Box<dyn Subscriber<Input=<Self as Publisher>::Output> + 'a>) {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
note: first, the lifetime cannot outlive the anonymous lifetime defined here...
--> $DIR/issue-20831-debruijn.rs:28:58
note: first, the lifetime cannot outlive the anonymous lifetime as defined here...
--> $DIR/issue-20831-debruijn.rs:28:18
|
LL | fn subscribe(&mut self, t : Box<dyn Subscriber<Input=<Self as Publisher>::Output> + 'a>) {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^
| ^
note: ...but the lifetime must also be valid for the lifetime `'a` as defined here...
--> $DIR/issue-20831-debruijn.rs:26:6
|