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Remove in-band lifetimes

This commit is contained in:
Michael Goulet 2022-02-09 18:42:32 -08:00
parent 4e82f35492
commit bb548a918a
67 changed files with 58 additions and 1459 deletions

View file

@ -1844,7 +1844,6 @@ impl<'tcx> LifetimeContext<'_, 'tcx> {
lifetime_ref
);
err.span_label(lifetime_ref.span, "undeclared lifetime");
let mut suggests_in_band = false;
let mut suggested_spans = vec![];
for missing in &self.missing_named_lifetime_spots {
match missing {
@ -1860,7 +1859,6 @@ impl<'tcx> LifetimeContext<'_, 'tcx> {
}) {
(param.span.shrink_to_lo(), format!("{}, ", lifetime_ref))
} else {
suggests_in_band = true;
(generics.span, format!("<{}>", lifetime_ref))
};
if suggested_spans.contains(&span) {
@ -1895,15 +1893,6 @@ impl<'tcx> LifetimeContext<'_, 'tcx> {
_ => {}
}
}
if self.tcx.sess.is_nightly_build()
&& !self.tcx.features().in_band_lifetimes
&& suggests_in_band
{
err.help(
"if you want to experiment with in-band lifetime bindings, \
add `#![feature(in_band_lifetimes)]` to the crate attributes",
);
}
err.emit();
}

View file

@ -16,7 +16,7 @@ use rustc_hir::def_id::{DefIdMap, LocalDefId};
use rustc_hir::hir_id::ItemLocalId;
use rustc_hir::intravisit::{self, Visitor};
use rustc_hir::{GenericArg, GenericParam, LifetimeName, Node, ParamName, QPath};
use rustc_hir::{GenericParamKind, HirIdMap, HirIdSet, LifetimeParamKind};
use rustc_hir::{GenericParamKind, HirIdMap, HirIdSet};
use rustc_middle::hir::map::Map;
use rustc_middle::hir::nested_filter;
use rustc_middle::middle::resolve_lifetime::*;
@ -1325,9 +1325,6 @@ impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> {
}
fn visit_generics(&mut self, generics: &'tcx hir::Generics<'tcx>) {
if !self.trait_definition_only {
check_mixed_explicit_and_in_band_defs(self.tcx, &generics.params);
}
let scope = Scope::TraitRefBoundary { s: self.scope };
self.with(scope, |_, this| {
for param in generics.params {
@ -1535,30 +1532,6 @@ impl ShadowKind {
}
}
fn check_mixed_explicit_and_in_band_defs(tcx: TyCtxt<'_>, params: &[hir::GenericParam<'_>]) {
let lifetime_params: Vec<_> = params
.iter()
.filter_map(|param| match param.kind {
GenericParamKind::Lifetime { kind, .. } => Some((kind, param.span)),
_ => None,
})
.collect();
let explicit = lifetime_params.iter().find(|(kind, _)| *kind == LifetimeParamKind::Explicit);
let in_band = lifetime_params.iter().find(|(kind, _)| *kind == LifetimeParamKind::InBand);
if let (Some((_, explicit_span)), Some((_, in_band_span))) = (explicit, in_band) {
struct_span_err!(
tcx.sess,
*in_band_span,
E0688,
"cannot mix in-band and explicit lifetime definitions"
)
.span_label(*in_band_span, "in-band lifetime definition here")
.span_label(*explicit_span, "explicit lifetime definition here")
.emit();
}
}
fn signal_shadowing_problem(tcx: TyCtxt<'_>, name: Symbol, orig: Original, shadower: Shadower) {
let mut err = if let (ShadowKind::Lifetime, ShadowKind::Lifetime) = (orig.kind, shadower.kind) {
// lifetime/lifetime shadowing is an error
@ -1845,13 +1818,7 @@ impl<'a, 'tcx> LifetimeContext<'a, 'tcx> {
fn lifetime_deletion_span(&self, name: Ident, generics: &hir::Generics<'_>) -> Option<Span> {
generics.params.iter().enumerate().find_map(|(i, param)| {
if param.name.ident() == name {
let in_band = matches!(
param.kind,
hir::GenericParamKind::Lifetime { kind: hir::LifetimeParamKind::InBand }
);
if in_band {
Some(param.span)
} else if generics.params.len() == 1 {
if generics.params.len() == 1 {
// if sole lifetime, remove the entire `<>` brackets
Some(generics.span)
} else {
@ -2337,39 +2304,6 @@ impl<'a, 'tcx> LifetimeContext<'a, 'tcx> {
}
}
// Check for fn-syntax conflicts with in-band lifetime definitions
if !self.trait_definition_only && self.is_in_fn_syntax {
match def {
Region::EarlyBound(_, _, LifetimeDefOrigin::InBand)
| Region::LateBound(_, _, _, LifetimeDefOrigin::InBand) => {
struct_span_err!(
self.tcx.sess,
lifetime_ref.span,
E0687,
"lifetimes used in `fn` or `Fn` syntax must be \
explicitly declared using `<...>` binders"
)
.span_label(lifetime_ref.span, "in-band lifetime definition")
.emit();
}
Region::Static
| Region::EarlyBound(
_,
_,
LifetimeDefOrigin::ExplicitOrElided | LifetimeDefOrigin::Error,
)
| Region::LateBound(
_,
_,
_,
LifetimeDefOrigin::ExplicitOrElided | LifetimeDefOrigin::Error,
)
| Region::LateBoundAnon(..)
| Region::Free(..) => {}
}
}
self.insert_lifetime(lifetime_ref, def);
} else {
self.emit_undeclared_lifetime_error(lifetime_ref);