use crate::diagnostics::{ImportSuggestion, LabelSuggestion, TypoSuggestion};
use crate::late::lifetimes::{ElisionFailureInfo, LifetimeContext};
use crate::late::{AliasPossibility, LateResolutionVisitor, RibKind};
-use crate::late::{LifetimeBinderKind, LifetimeRibKind};
+use crate::late::{LifetimeBinderKind, LifetimeRibKind, LifetimeUseSet};
use crate::path_names_to_string;
use crate::{Module, ModuleKind, ModuleOrUniformRoot};
use crate::{PathResult, PathSource, Segment};
-use rustc_ast::visit::{FnCtxt, FnKind};
+use rustc_ast::visit::{FnCtxt, FnKind, LifetimeCtxt};
use rustc_ast::{
self as ast, AssocItemKind, Expr, ExprKind, GenericParam, GenericParamKind, Item, ItemKind,
NodeId, Path, Ty, TyKind,
};
+use rustc_ast_lowering::ResolverAstLowering;
use rustc_ast_pretty::pprust::path_segment_to_string;
use rustc_data_structures::fx::FxHashSet;
use rustc_errors::{
use rustc_hir::def::{self, CtorKind, CtorOf, DefKind};
use rustc_hir::def_id::{DefId, CRATE_DEF_ID, LOCAL_CRATE};
use rustc_hir::PrimTy;
+use rustc_session::lint;
use rustc_session::parse::feature_err;
use rustc_span::edition::Edition;
use rustc_span::hygiene::MacroKind;
}
}
-crate enum MissingLifetimeSpot<'tcx> {
+pub(crate) enum MissingLifetimeSpot<'tcx> {
Generics(&'tcx hir::Generics<'tcx>),
HigherRanked { span: Span, span_type: ForLifetimeSpanType },
Static,
}
-crate enum ForLifetimeSpanType {
+pub(crate) enum ForLifetimeSpanType {
BoundEmpty,
BoundTail,
TypeEmpty,
}
impl ForLifetimeSpanType {
- crate fn descr(&self) -> &'static str {
+ pub(crate) fn descr(&self) -> &'static str {
match self {
Self::BoundEmpty | Self::BoundTail => "bound",
Self::TypeEmpty | Self::TypeTail => "type",
}
}
- crate fn suggestion(&self, sugg: &str) -> String {
+ pub(crate) fn suggestion(&self, sugg: &str) -> String {
match self {
Self::BoundEmpty | Self::TypeEmpty => format!("for<{}> ", sugg),
Self::BoundTail | Self::TypeTail => format!(", {}", sugg),
/// Given the target `ident` and `kind`, search for the similarly named associated item
/// in `self.current_trait_ref`.
- crate fn find_similarly_named_assoc_item(
+ pub(crate) fn find_similarly_named_assoc_item(
&mut self,
ident: Symbol,
kind: &AssocItemKind,
}
}
- crate fn report_missing_type_error(
+ pub(crate) fn report_missing_type_error(
&self,
path: &[Segment],
) -> Option<(Span, &'static str, String, Applicability)> {
/// Given the target `label`, search the `rib_index`th label rib for similarly named labels,
/// optionally returning the closest match and whether it is reachable.
- crate fn suggestion_for_label_in_rib(
+ pub(crate) fn suggestion_for_label_in_rib(
&self,
rib_index: usize,
label: Ident,
})
}
- crate fn emit_undeclared_lifetime_error(
+ pub(crate) fn maybe_report_lifetime_uses(
+ &mut self,
+ generics_span: Span,
+ params: &[ast::GenericParam],
+ ) {
+ for (param_index, param) in params.iter().enumerate() {
+ let GenericParamKind::Lifetime = param.kind else { continue };
+
+ let def_id = self.r.local_def_id(param.id);
+
+ let use_set = self.lifetime_uses.remove(&def_id);
+ debug!(
+ "Use set for {:?}({:?} at {:?}) is {:?}",
+ def_id, param.ident, param.ident.span, use_set
+ );
+
+ let deletion_span = || {
+ if params.len() == 1 {
+ // if sole lifetime, remove the entire `<>` brackets
+ generics_span
+ } else if param_index == 0 {
+ // if removing within `<>` brackets, we also want to
+ // delete a leading or trailing comma as appropriate
+ param.span().to(params[param_index + 1].span().shrink_to_lo())
+ } else {
+ // if removing within `<>` brackets, we also want to
+ // delete a leading or trailing comma as appropriate
+ params[param_index - 1].span().shrink_to_hi().to(param.span())
+ }
+ };
+ match use_set {
+ Some(LifetimeUseSet::Many) => {}
+ Some(LifetimeUseSet::One { use_span, use_ctxt }) => {
+ debug!(?param.ident, ?param.ident.span, ?use_span);
+
+ let elidable = matches!(use_ctxt, LifetimeCtxt::Rptr);
+
+ let deletion_span = deletion_span();
+ self.r.lint_buffer.buffer_lint_with_diagnostic(
+ lint::builtin::SINGLE_USE_LIFETIMES,
+ param.id,
+ param.ident.span,
+ &format!("lifetime parameter `{}` only used once", param.ident),
+ lint::BuiltinLintDiagnostics::SingleUseLifetime {
+ param_span: param.ident.span,
+ use_span: Some((use_span, elidable)),
+ deletion_span,
+ },
+ );
+ }
+ None => {
+ debug!(?param.ident, ?param.ident.span);
+
+ let deletion_span = deletion_span();
+ self.r.lint_buffer.buffer_lint_with_diagnostic(
+ lint::builtin::UNUSED_LIFETIMES,
+ param.id,
+ param.ident.span,
+ &format!("lifetime parameter `{}` never used", param.ident),
+ lint::BuiltinLintDiagnostics::SingleUseLifetime {
+ param_span: param.ident.span,
+ use_span: None,
+ deletion_span,
+ },
+ );
+ }
+ }
+ }
+ }
+
+ pub(crate) fn emit_undeclared_lifetime_error(
&self,
lifetime_ref: &ast::Lifetime,
outer_lifetime_ref: Option<Ident>,
for rib in self.lifetime_ribs.iter().rev() {
match rib.kind {
- LifetimeRibKind::Generics { parent: _, span, kind } => {
+ LifetimeRibKind::Generics { binder: _, span, kind } => {
if !span.can_be_used_for_suggestions() && suggest_note {
suggest_note = false; // Avoid displaying the same help multiple times.
err.span_label(
err.emit();
}
- crate fn emit_non_static_lt_in_const_generic_error(&self, lifetime_ref: &ast::Lifetime) {
+ pub(crate) fn emit_non_static_lt_in_const_generic_error(&self, lifetime_ref: &ast::Lifetime) {
struct_span_err!(
self.r.session,
lifetime_ref.ident.span,
/// Non-static lifetimes are prohibited in anonymous constants under `min_const_generics`.
/// This function will emit an error if `generic_const_exprs` is not enabled, the body identified by
/// `body_id` is an anonymous constant and `lifetime_ref` is non-static.
- crate fn maybe_emit_forbidden_non_static_lifetime_error(&self, lifetime_ref: &ast::Lifetime) {
+ pub(crate) fn maybe_emit_forbidden_non_static_lifetime_error(
+ &self,
+ lifetime_ref: &ast::Lifetime,
+ ) {
let feature_active = self.r.session.features_untracked().generic_const_exprs;
if !feature_active {
feature_err(
}
impl<'tcx> LifetimeContext<'_, 'tcx> {
- crate fn report_missing_lifetime_specifiers(
+ pub(crate) fn report_missing_lifetime_specifiers(
&self,
spans: Vec<Span>,
count: usize,
}
/// Returns whether to add `'static` lifetime to the suggested lifetime list.
- crate fn report_elision_failure(
+ pub(crate) fn report_elision_failure(
&mut self,
diag: &mut Diagnostic,
params: &[ElisionFailureInfo],
}
}
- crate fn is_trait_ref_fn_scope(&mut self, trait_ref: &'tcx hir::PolyTraitRef<'tcx>) -> bool {
+ pub(crate) fn is_trait_ref_fn_scope(
+ &mut self,
+ trait_ref: &'tcx hir::PolyTraitRef<'tcx>,
+ ) -> bool {
if let def::Res::Def(_, did) = trait_ref.trait_ref.path.res {
if [
self.tcx.lang_items().fn_once_trait(),
false
}
- crate fn add_missing_lifetime_specifiers_label(
+ pub(crate) fn add_missing_lifetime_specifiers_label(
&self,
err: &mut Diagnostic,
mut spans_with_counts: Vec<(Span, usize)>,