Auto merge of #104048 - cjgillot:split-lifetime, r=compiler-errors

Separate lifetime ident from lifetime resolution in HIR

Drive-by: change how suggested generic args are computed.
Fixes https://github.com/rust-lang/rust/issues/103815

I recommend reviewing commit-by-commit.

clippy_lints/src/lifetimes.rs

@@ -10,8 +10,8 @@ use rustc_hir::lang_items;
 use rustc_hir::FnRetTy::Return;
 use rustc_hir::{
     BareFnTy, BodyId, FnDecl, GenericArg, GenericBound, GenericParam, GenericParamKind, Generics, Impl, ImplItem,
-    ImplItemKind, Item, ItemKind, Lifetime, LifetimeName, ParamName, PolyTraitRef, PredicateOrigin, TraitFn, TraitItem,
-    TraitItemKind, Ty, TyKind, WherePredicate,
+    ImplItemKind, Item, ItemKind, Lifetime, LifetimeName, LifetimeParamKind, PolyTraitRef, PredicateOrigin, TraitFn,
+    TraitItem, TraitItemKind, Ty, TyKind, WherePredicate,
 };
 use rustc_lint::{LateContext, LateLintPass};
 use rustc_middle::hir::nested_filter as middle_nested_filter;
@@ -180,7 +180,7 @@ fn check_fn_inner<'tcx>(
                             _ => None,
                         });
                         for bound in lifetimes {
-                            if bound.name != LifetimeName::Static && !bound.is_elided() {
+                            if !bound.is_static() && !bound.is_elided() {
                                 return;
                             }
                         }
@@ -414,17 +414,13 @@ impl<'a, 'tcx> RefVisitor<'a, 'tcx> {
 
     fn record(&mut self, lifetime: &Option<Lifetime>) {
         if let Some(ref lt) = *lifetime {
-            if lt.name == LifetimeName::Static {
+            if lt.is_static() {
                 self.lts.push(RefLt::Static);
-            } else if let LifetimeName::Param(_, ParamName::Fresh) = lt.name {
+            } else if lt.is_anonymous() {
                 // Fresh lifetimes generated should be ignored.
                 self.lts.push(RefLt::Unnamed);
-            } else if lt.is_elided() {
-                self.lts.push(RefLt::Unnamed);
-            } else if let LifetimeName::Param(def_id, _) = lt.name {
+            } else if let LifetimeName::Param(def_id) = lt.res {
                 self.lts.push(RefLt::Named(def_id));
-            } else {
-                self.lts.push(RefLt::Unnamed);
             }
         } else {
             self.lts.push(RefLt::Unnamed);
@@ -472,7 +468,7 @@ impl<'a, 'tcx> Visitor<'tcx> for RefVisitor<'a, 'tcx> {
                 walk_item(self, item);
                 self.lts.truncate(len);
                 self.lts.extend(bounds.iter().filter_map(|bound| match bound {
-                    GenericArg::Lifetime(l) => Some(if let LifetimeName::Param(def_id, _) = l.name {
+                    GenericArg::Lifetime(l) => Some(if let LifetimeName::Param(def_id) = l.res {
                         RefLt::Named(def_id)
                     } else {
                         RefLt::Unnamed
@@ -498,10 +494,8 @@ impl<'a, 'tcx> Visitor<'tcx> for RefVisitor<'a, 'tcx> {
     }
 
     fn visit_generic_arg(&mut self, generic_arg: &'tcx GenericArg<'tcx>) {
-        if let GenericArg::Lifetime(l) = generic_arg
-            && let LifetimeName::Param(def_id, _) = l.name
-        {
-            self.lifetime_generic_arg_spans.entry(def_id).or_insert(l.span);
+        if let GenericArg::Lifetime(l) = generic_arg && let LifetimeName::Param(def_id) = l.res {
+            self.lifetime_generic_arg_spans.entry(def_id).or_insert(l.ident.span);
         }
         // Replace with `walk_generic_arg` if/when https://github.com/rust-lang/rust/pull/103692 lands.
         // walk_generic_arg(self, generic_arg);
@@ -577,7 +571,7 @@ where
 
     // for lifetimes as parameters of generics
     fn visit_lifetime(&mut self, lifetime: &'tcx Lifetime) {
-        self.map.remove(&lifetime.name.ident().name);
+        self.map.remove(&lifetime.ident.name);
     }
 
     fn visit_generic_param(&mut self, param: &'tcx GenericParam<'_>) {
@@ -601,7 +595,9 @@ fn report_extra_lifetimes<'tcx>(cx: &LateContext<'tcx>, func: &'tcx FnDecl<'_>,
         .params
         .iter()
         .filter_map(|par| match par.kind {
-            GenericParamKind::Lifetime { .. } => Some((par.name.ident().name, par.span)),
+            GenericParamKind::Lifetime {
+                kind: LifetimeParamKind::Explicit,
+            } => Some((par.name.ident().name, par.span)),
             _ => None,
         })
         .collect();
@@ -626,7 +622,9 @@ fn report_extra_impl_lifetimes<'tcx>(cx: &LateContext<'tcx>, impl_: &'tcx Impl<'
         .params
         .iter()
         .filter_map(|par| match par.kind {
-            GenericParamKind::Lifetime { .. } => Some((par.name.ident().name, par.span)),
+            GenericParamKind::Lifetime {
+                kind: LifetimeParamKind::Explicit,
+            } => Some((par.name.ident().name, par.span)),
             _ => None,
         })
         .collect();
@@ -653,7 +651,7 @@ struct BodyLifetimeChecker {
 impl<'tcx> Visitor<'tcx> for BodyLifetimeChecker {
     // for lifetimes as parameters of generics
     fn visit_lifetime(&mut self, lifetime: &'tcx Lifetime) {
-        if lifetime.name.ident().name != kw::UnderscoreLifetime && lifetime.name.ident().name != kw::StaticLifetime {
+        if !lifetime.is_anonymous() && lifetime.ident.name != kw::StaticLifetime {
             self.lifetimes_used_in_body = true;
         }
     }

clippy_lints/src/manual_async_fn.rs

@@ -118,7 +118,7 @@ fn future_trait_ref<'tcx>(
                 .iter()
                 .filter_map(|bound| {
                     if let GenericArg::Lifetime(lt) = bound {
-                        Some(lt.name)
+                        Some(lt.res)
                     } else {
                         None
                     }
@@ -153,7 +153,7 @@ fn captures_all_lifetimes(inputs: &[Ty<'_>], output_lifetimes: &[LifetimeName])
         .iter()
         .filter_map(|ty| {
             if let TyKind::Rptr(lt, _) = ty.kind {
-                Some(lt.name)
+                Some(lt.res)
             } else {
                 None
             }

clippy_lints/src/ptr.rs

@@ -12,8 +12,8 @@ use rustc_hir::hir_id::HirIdMap;
 use rustc_hir::intravisit::{walk_expr, Visitor};
 use rustc_hir::{
     self as hir, AnonConst, BinOpKind, BindingAnnotation, Body, Expr, ExprKind, FnRetTy, FnSig, GenericArg,
-    ImplItemKind, ItemKind, Lifetime, LifetimeName, Mutability, Node, Param, ParamName, PatKind, QPath, TraitFn,
-    TraitItem, TraitItemKind, TyKind, Unsafety,
+    ImplItemKind, ItemKind, Lifetime, Mutability, Node, Param, PatKind, QPath, TraitFn, TraitItem, TraitItemKind,
+    TyKind, Unsafety,
 };
 use rustc_infer::infer::TyCtxtInferExt;
 use rustc_infer::traits::{Obligation, ObligationCause};
@@ -343,21 +343,16 @@ impl PtrArg<'_> {
 }
 
 struct RefPrefix {
-    lt: LifetimeName,
+    lt: Lifetime,
     mutability: Mutability,
 }
 impl fmt::Display for RefPrefix {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         use fmt::Write;
         f.write_char('&')?;
-        match self.lt {
-            LifetimeName::Param(_, ParamName::Plain(name)) => {
-                name.fmt(f)?;
-                f.write_char(' ')?;
-            },
-            LifetimeName::Infer => f.write_str("'_ ")?,
-            LifetimeName::Static => f.write_str("'static ")?,
-            _ => (),
+        if !self.lt.is_anonymous() {
+            self.lt.ident.fmt(f)?;
+            f.write_char(' ')?;
         }
         f.write_str(self.mutability.prefix_str())
     }
@@ -495,7 +490,7 @@ fn check_fn_args<'cx, 'tcx: 'cx>(
                         ty_name: name.ident.name,
                         method_renames,
                         ref_prefix: RefPrefix {
-                            lt: lt.name,
+                            lt: lt.clone(),
                             mutability,
                         },
                         deref_ty,

clippy_lints/src/types/borrowed_box.rs

@@ -31,10 +31,10 @@ pub(super) fn check(cx: &LateContext<'_>, hir_ty: &hir::Ty<'_>, lt: &Lifetime, m
                         return false;
                     }
 
-                    let ltopt = if lt.name.is_anonymous() {
+                    let ltopt = if lt.is_anonymous() {
                         String::new()
                     } else {
-                        format!("{} ", lt.name.ident().as_str())
+                        format!("{} ", lt.ident.as_str())
                     };
 
                     if mut_ty.mutbl == Mutability::Mut {

clippy_utils/src/hir_utils.rs

@@ -7,7 +7,7 @@ use rustc_hir::def::Res;
 use rustc_hir::HirIdMap;
 use rustc_hir::{
     ArrayLen, BinOpKind, BindingAnnotation, Block, BodyId, Closure, Expr, ExprField, ExprKind, FnRetTy, GenericArg,
-    GenericArgs, Guard, HirId, InlineAsmOperand, Let, Lifetime, LifetimeName, ParamName, Pat, PatField, PatKind, Path,
+    GenericArgs, Guard, HirId, InlineAsmOperand, Let, Lifetime, LifetimeName, Pat, PatField, PatKind, Path,
     PathSegment, PrimTy, QPath, Stmt, StmtKind, Ty, TyKind, TypeBinding,
 };
 use rustc_lexer::{tokenize, TokenKind};
@@ -337,7 +337,7 @@ impl HirEqInterExpr<'_, '_, '_> {
     }
 
     fn eq_lifetime(left: &Lifetime, right: &Lifetime) -> bool {
-        left.name == right.name
+        left.res == right.res
     }
 
     fn eq_pat_field(&mut self, left: &PatField<'_>, right: &PatField<'_>) -> bool {
@@ -925,16 +925,10 @@ impl<'a, 'tcx> SpanlessHash<'a, 'tcx> {
     }
 
     pub fn hash_lifetime(&mut self, lifetime: &Lifetime) {
-        std::mem::discriminant(&lifetime.name).hash(&mut self.s);
-        if let LifetimeName::Param(param_id, ref name) = lifetime.name {
-            std::mem::discriminant(name).hash(&mut self.s);
+        lifetime.ident.name.hash(&mut self.s);
+        std::mem::discriminant(&lifetime.res).hash(&mut self.s);
+        if let LifetimeName::Param(param_id) = lifetime.res {
             param_id.hash(&mut self.s);
-            match name {
-                ParamName::Plain(ref ident) => {
-                    ident.name.hash(&mut self.s);
-                },
-                ParamName::Fresh | ParamName::Error => {},
-            }
         }
     }