Rollup merge of #118199 - compiler-errors:qpath, r=lcnr

Remove `HirId` from `QPath::LangItem`

Remove `HirId` from `QPath::LangItem`, since there was only *one* use-case (`ObligationCauseCode::AwaitableExpr`), which we can instead recover by walking the HIR tree.

compiler/rustc_ast_lowering/src/expr.rs

@@ -560,7 +560,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
         expr: &'hir hir::Expr<'hir>,
         overall_span: Span,
     ) -> &'hir hir::Expr<'hir> {
-        let constructor = self.arena.alloc(self.expr_lang_item_path(method_span, lang_item, None));
+        let constructor = self.arena.alloc(self.expr_lang_item_path(method_span, lang_item));
         self.expr_call(overall_span, constructor, std::slice::from_ref(expr))
     }
 
@@ -614,7 +614,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
         // Resume argument type: `ResumeTy`
         let unstable_span =
             self.mark_span_with_reason(DesugaringKind::Async, span, self.allow_gen_future.clone());
-        let resume_ty = hir::QPath::LangItem(hir::LangItem::ResumeTy, unstable_span, None);
+        let resume_ty = hir::QPath::LangItem(hir::LangItem::ResumeTy, unstable_span);
         let input_ty = hir::Ty {
             hir_id: self.next_id(),
             kind: hir::TyKind::Path(resume_ty),
@@ -818,19 +818,16 @@ impl<'hir> LoweringContext<'_, 'hir> {
                 span,
                 hir::LangItem::PinNewUnchecked,
                 arena_vec![self; ref_mut_awaitee],
-                Some(expr_hir_id),
             );
             let get_context = self.expr_call_lang_item_fn_mut(
                 gen_future_span,
                 hir::LangItem::GetContext,
                 arena_vec![self; task_context],
-                Some(expr_hir_id),
             );
             let call = self.expr_call_lang_item_fn(
                 span,
                 hir::LangItem::FuturePoll,
                 arena_vec![self; new_unchecked, get_context],
-                Some(expr_hir_id),
             );
             self.arena.alloc(self.expr_unsafe(call))
         };
@@ -843,12 +840,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
             let (x_pat, x_pat_hid) = self.pat_ident(gen_future_span, x_ident);
             let x_expr = self.expr_ident(gen_future_span, x_ident, x_pat_hid);
             let ready_field = self.single_pat_field(gen_future_span, x_pat);
-            let ready_pat = self.pat_lang_item_variant(
-                span,
-                hir::LangItem::PollReady,
-                ready_field,
-                Some(expr_hir_id),
-            );
+            let ready_pat = self.pat_lang_item_variant(span, hir::LangItem::PollReady, ready_field);
             let break_x = self.with_loop_scope(loop_node_id, move |this| {
                 let expr_break =
                     hir::ExprKind::Break(this.lower_loop_destination(None), Some(x_expr));
@@ -859,12 +851,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
 
         // `::std::task::Poll::Pending => {}`
         let pending_arm = {
-            let pending_pat = self.pat_lang_item_variant(
-                span,
-                hir::LangItem::PollPending,
-                &[],
-                Some(expr_hir_id),
-            );
+            let pending_pat = self.pat_lang_item_variant(span, hir::LangItem::PollPending, &[]);
             let empty_block = self.expr_block_empty(span);
             self.arm(pending_pat, empty_block)
         };
@@ -922,7 +909,6 @@ impl<'hir> LoweringContext<'_, 'hir> {
             span,
             hir::LangItem::IntoFutureIntoFuture,
             arena_vec![self; expr],
-            Some(expr_hir_id),
         );
 
         // match <into_future_expr> {
@@ -1379,8 +1365,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
     fn lower_expr_range_closed(&mut self, span: Span, e1: &Expr, e2: &Expr) -> hir::ExprKind<'hir> {
         let e1 = self.lower_expr_mut(e1);
         let e2 = self.lower_expr_mut(e2);
-        let fn_path =
-            hir::QPath::LangItem(hir::LangItem::RangeInclusiveNew, self.lower_span(span), None);
+        let fn_path = hir::QPath::LangItem(hir::LangItem::RangeInclusiveNew, self.lower_span(span));
         let fn_expr = self.arena.alloc(self.expr(span, hir::ExprKind::Path(fn_path)));
         hir::ExprKind::Call(fn_expr, arena_vec![self; e1, e2])
     }
@@ -1421,7 +1406,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
         );
 
         hir::ExprKind::Struct(
-            self.arena.alloc(hir::QPath::LangItem(lang_item, self.lower_span(span), None)),
+            self.arena.alloc(hir::QPath::LangItem(lang_item, self.lower_span(span))),
             fields,
             None,
         )
@@ -1590,7 +1575,6 @@ impl<'hir> LoweringContext<'_, 'hir> {
                 head_span,
                 hir::LangItem::IteratorNext,
                 arena_vec![self; ref_mut_iter],
-                None,
             );
             let arms = arena_vec![self; none_arm, some_arm];
 
@@ -1619,7 +1603,6 @@ impl<'hir> LoweringContext<'_, 'hir> {
                 head_span,
                 hir::LangItem::IntoIterIntoIter,
                 arena_vec![self; head],
-                None,
             )
         };
 
@@ -1675,7 +1658,6 @@ impl<'hir> LoweringContext<'_, 'hir> {
                 unstable_span,
                 hir::LangItem::TryTraitBranch,
                 arena_vec![self; sub_expr],
-                None,
             )
         };
 
@@ -1880,9 +1862,8 @@ impl<'hir> LoweringContext<'_, 'hir> {
         span: Span,
         lang_item: hir::LangItem,
         args: &'hir [hir::Expr<'hir>],
-        hir_id: Option<hir::HirId>,
     ) -> hir::Expr<'hir> {
-        let path = self.arena.alloc(self.expr_lang_item_path(span, lang_item, hir_id));
+        let path = self.arena.alloc(self.expr_lang_item_path(span, lang_item));
         self.expr_call_mut(span, path, args)
     }
 
@@ -1891,21 +1872,12 @@ impl<'hir> LoweringContext<'_, 'hir> {
         span: Span,
         lang_item: hir::LangItem,
         args: &'hir [hir::Expr<'hir>],
-        hir_id: Option<hir::HirId>,
     ) -> &'hir hir::Expr<'hir> {
-        self.arena.alloc(self.expr_call_lang_item_fn_mut(span, lang_item, args, hir_id))
+        self.arena.alloc(self.expr_call_lang_item_fn_mut(span, lang_item, args))
     }
 
-    fn expr_lang_item_path(
-        &mut self,
-        span: Span,
-        lang_item: hir::LangItem,
-        hir_id: Option<hir::HirId>,
-    ) -> hir::Expr<'hir> {
-        self.expr(
-            span,
-            hir::ExprKind::Path(hir::QPath::LangItem(lang_item, self.lower_span(span), hir_id)),
-        )
+    fn expr_lang_item_path(&mut self, span: Span, lang_item: hir::LangItem) -> hir::Expr<'hir> {
+        self.expr(span, hir::ExprKind::Path(hir::QPath::LangItem(lang_item, self.lower_span(span))))
     }
 
     /// `<LangItem>::name`
@@ -1918,7 +1890,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
         let path = hir::ExprKind::Path(hir::QPath::TypeRelative(
             self.arena.alloc(self.ty(
                 span,
-                hir::TyKind::Path(hir::QPath::LangItem(lang_item, self.lower_span(span), None)),
+                hir::TyKind::Path(hir::QPath::LangItem(lang_item, self.lower_span(span))),
             )),
             self.arena.alloc(hir::PathSegment::new(
                 Ident::new(name, span),

compiler/rustc_ast_lowering/src/lib.rs

@@ -2304,21 +2304,21 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
 
     fn pat_cf_continue(&mut self, span: Span, pat: &'hir hir::Pat<'hir>) -> &'hir hir::Pat<'hir> {
         let field = self.single_pat_field(span, pat);
-        self.pat_lang_item_variant(span, hir::LangItem::ControlFlowContinue, field, None)
+        self.pat_lang_item_variant(span, hir::LangItem::ControlFlowContinue, field)
     }
 
     fn pat_cf_break(&mut self, span: Span, pat: &'hir hir::Pat<'hir>) -> &'hir hir::Pat<'hir> {
         let field = self.single_pat_field(span, pat);
-        self.pat_lang_item_variant(span, hir::LangItem::ControlFlowBreak, field, None)
+        self.pat_lang_item_variant(span, hir::LangItem::ControlFlowBreak, field)
     }
 
     fn pat_some(&mut self, span: Span, pat: &'hir hir::Pat<'hir>) -> &'hir hir::Pat<'hir> {
         let field = self.single_pat_field(span, pat);
-        self.pat_lang_item_variant(span, hir::LangItem::OptionSome, field, None)
+        self.pat_lang_item_variant(span, hir::LangItem::OptionSome, field)
     }
 
     fn pat_none(&mut self, span: Span) -> &'hir hir::Pat<'hir> {
-        self.pat_lang_item_variant(span, hir::LangItem::OptionNone, &[], None)
+        self.pat_lang_item_variant(span, hir::LangItem::OptionNone, &[])
     }
 
     fn single_pat_field(
@@ -2341,9 +2341,8 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
         span: Span,
         lang_item: hir::LangItem,
         fields: &'hir [hir::PatField<'hir>],
-        hir_id: Option<hir::HirId>,
     ) -> &'hir hir::Pat<'hir> {
-        let qpath = hir::QPath::LangItem(lang_item, self.lower_span(span), hir_id);
+        let qpath = hir::QPath::LangItem(lang_item, self.lower_span(span));
         self.pat(span, hir::PatKind::Struct(qpath, fields, false))
     }
 

compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs

@@ -445,7 +445,6 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                         && let hir::ExprKind::Path(hir::QPath::LangItem(
                             LangItem::IntoIterIntoIter,
                             _,
-                            _,
                         )) = call_expr.kind
                     {
                         // Do not suggest `.clone()` in a `for` loop, we already suggest borrowing.
@@ -1346,11 +1345,8 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                 // };
                 // corresponding to the desugaring of a for loop `for <pat> in <head> { <body> }`.
                 if let hir::ExprKind::Call(path, [arg]) = ex.kind
-                    && let hir::ExprKind::Path(hir::QPath::LangItem(
-                        LangItem::IntoIterIntoIter,
-                        _,
-                        _,
-                    )) = path.kind
+                    && let hir::ExprKind::Path(hir::QPath::LangItem(LangItem::IntoIterIntoIter, _)) =
+                        path.kind
                     && arg.span.contains(self.issue_span)
                 {
                     // Find `IntoIterator::into_iter(<head>)`
@@ -1368,10 +1364,10 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                         ..
                     }) = stmt.kind
                     && let hir::ExprKind::Call(path, _args) = call.kind
-                    && let hir::ExprKind::Path(hir::QPath::LangItem(LangItem::IteratorNext, _, _)) =
+                    && let hir::ExprKind::Path(hir::QPath::LangItem(LangItem::IteratorNext, _)) =
                         path.kind
                     && let hir::PatKind::Struct(path, [field, ..], _) = bind.pat.kind
-                    && let hir::QPath::LangItem(LangItem::OptionSome, pat_span, _) = path
+                    && let hir::QPath::LangItem(LangItem::OptionSome, pat_span) = path
                     && call.span.contains(self.issue_span)
                 {
                     // Find `<pat>` and the span for the whole `for` loop.

compiler/rustc_hir/src/hir.rs

@@ -2058,8 +2058,8 @@ pub enum QPath<'hir> {
     /// the `X` and `Y` nodes each being a `TyKind::Path(QPath::TypeRelative(..))`.
     TypeRelative(&'hir Ty<'hir>, &'hir PathSegment<'hir>),
 
-    /// Reference to a `#[lang = "foo"]` item. `HirId` of the inner expr.
-    LangItem(LangItem, Span, Option<HirId>),
+    /// Reference to a `#[lang = "foo"]` item.
+    LangItem(LangItem, Span),
 }
 
 impl<'hir> QPath<'hir> {
@@ -2068,7 +2068,7 @@ impl<'hir> QPath<'hir> {
         match *self {
             QPath::Resolved(_, path) => path.span,
             QPath::TypeRelative(qself, ps) => qself.span.to(ps.ident.span),
-            QPath::LangItem(_, span, _) => span,
+            QPath::LangItem(_, span) => span,
         }
     }
 
@@ -2078,7 +2078,7 @@ impl<'hir> QPath<'hir> {
         match *self {
             QPath::Resolved(_, path) => path.span,
             QPath::TypeRelative(qself, _) => qself.span,
-            QPath::LangItem(_, span, _) => span,
+            QPath::LangItem(_, span) => span,
         }
     }
 }

compiler/rustc_hir_analysis/src/astconv/mod.rs

@@ -2546,7 +2546,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
                     .map(|(ty, _, _)| ty)
                     .unwrap_or_else(|guar| Ty::new_error(tcx, guar))
             }
-            &hir::TyKind::Path(hir::QPath::LangItem(lang_item, span, _)) => {
+            &hir::TyKind::Path(hir::QPath::LangItem(lang_item, span)) => {
                 let def_id = tcx.require_lang_item(lang_item, Some(span));
                 let (args, _) = self.create_args_for_ast_path(
                     span,

compiler/rustc_hir_pretty/src/lib.rs

@@ -1623,7 +1623,7 @@ impl<'a> State<'a> {
                 self.print_ident(item_segment.ident);
                 self.print_generic_args(item_segment.args(), colons_before_params)
             }
-            hir::QPath::LangItem(lang_item, span, _) => {
+            hir::QPath::LangItem(lang_item, span) => {
                 self.word("#[lang = \"");
                 self.print_ident(Ident::new(lang_item.name(), span));
                 self.word("\"]");

compiler/rustc_hir_typeck/src/expr.rs

@@ -289,8 +289,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             ExprKind::AddrOf(kind, mutbl, oprnd) => {
                 self.check_expr_addr_of(kind, mutbl, oprnd, expected, expr)
             }
-            ExprKind::Path(QPath::LangItem(lang_item, _, hir_id)) => {
-                self.check_lang_item_path(lang_item, expr, hir_id)
+            ExprKind::Path(QPath::LangItem(lang_item, _)) => {
+                self.check_lang_item_path(lang_item, expr)
             }
             ExprKind::Path(ref qpath) => self.check_expr_path(qpath, expr, &[]),
             ExprKind::InlineAsm(asm) => {
@@ -497,9 +497,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         &self,
         lang_item: hir::LangItem,
         expr: &'tcx hir::Expr<'tcx>,
-        hir_id: Option<hir::HirId>,
     ) -> Ty<'tcx> {
-        self.resolve_lang_item_path(lang_item, expr.span, expr.hir_id, hir_id).1
+        self.resolve_lang_item_path(lang_item, expr.span, expr.hir_id).1
     }
 
     pub(crate) fn check_expr_path(

compiler/rustc_hir_typeck/src/fn_ctxt/_impl.rs

@@ -753,7 +753,6 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         lang_item: hir::LangItem,
         span: Span,
         hir_id: hir::HirId,
-        expr_hir_id: Option<hir::HirId>,
     ) -> (Res, Ty<'tcx>) {
         let def_id = self.tcx.require_lang_item(lang_item, Some(span));
         let def_kind = self.tcx.def_kind(def_id);
@@ -770,7 +769,13 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
 
         let code = match lang_item {
             hir::LangItem::IntoFutureIntoFuture => {
-                Some(ObligationCauseCode::AwaitableExpr(expr_hir_id))
+                if let hir::Node::Expr(into_future_call) = self.tcx.hir().get_parent(hir_id)
+                    && let hir::ExprKind::Call(_, [arg0]) = &into_future_call.kind
+                {
+                    Some(ObligationCauseCode::AwaitableExpr(arg0.hir_id))
+                } else {
+                    None
+                }
             }
             hir::LangItem::IteratorNext | hir::LangItem::IntoIterIntoIter => {
                 Some(ObligationCauseCode::ForLoopIterator)

compiler/rustc_hir_typeck/src/fn_ctxt/checks.rs

@@ -1842,8 +1842,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
 
                 (result.map_or(Res::Err, |(kind, def_id)| Res::Def(kind, def_id)), ty)
             }
-            QPath::LangItem(lang_item, span, id) => {
-                let (res, ty) = self.resolve_lang_item_path(lang_item, span, hir_id, id);
+            QPath::LangItem(lang_item, span) => {
+                let (res, ty) = self.resolve_lang_item_path(lang_item, span, hir_id);
                 (res, self.handle_raw_ty(path_span, ty))
             }
         }

compiler/rustc_infer/src/infer/error_reporting/need_type_info.rs

@@ -1087,7 +1087,7 @@ impl<'a, 'tcx> FindInferSourceVisitor<'a, 'tcx> {
 
                 Box::new(segment.into_iter())
             }
-            hir::QPath::LangItem(_, _, _) => Box::new(iter::empty()),
+            hir::QPath::LangItem(_, _) => Box::new(iter::empty()),
         }
     }
 }

compiler/rustc_middle/src/traits/mod.rs

@@ -422,7 +422,7 @@ pub enum ObligationCauseCode<'tcx> {
     /// If `X` is the concrete type of an opaque type `impl Y`, then `X` must implement `Y`
     OpaqueType,
 
-    AwaitableExpr(Option<hir::HirId>),
+    AwaitableExpr(hir::HirId),
 
     ForLoopIterator,
 

compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs

@@ -1634,8 +1634,7 @@ impl<'tcx> TypeErrCtxtExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
 
     fn suggest_remove_await(&self, obligation: &PredicateObligation<'tcx>, err: &mut Diagnostic) {
         let hir = self.tcx.hir();
-        if let ObligationCauseCode::AwaitableExpr(Some(hir_id)) =
-            obligation.cause.code().peel_derives()
+        if let ObligationCauseCode::AwaitableExpr(hir_id) = obligation.cause.code().peel_derives()
             && let hir::Node::Expr(expr) = hir.get(*hir_id)
         {
             // FIXME: use `obligation.predicate.kind()...trait_ref.self_ty()` to see if we have `()`

src/tools/clippy/clippy_lints/src/methods/clone_on_copy.rs

@@ -61,7 +61,7 @@ pub(super) fn check(
                 // ? is a Call, makes sure not to rec *x?, but rather (*x)?
                 ExprKind::Call(hir_callee, _) => matches!(
                     hir_callee.kind,
-                    ExprKind::Path(QPath::LangItem(rustc_hir::LangItem::TryTraitBranch, _, _))
+                    ExprKind::Path(QPath::LangItem(rustc_hir::LangItem::TryTraitBranch, ..))
                 ),
                 ExprKind::MethodCall(_, self_arg, ..) if expr.hir_id == self_arg.hir_id => true,
                 ExprKind::Match(_, _, MatchSource::TryDesugar(_) | MatchSource::AwaitDesugar)

src/tools/clippy/clippy_lints/src/returns.rs

@@ -309,7 +309,7 @@ fn check_final_expr<'tcx>(
             let replacement = if let Some(inner_expr) = inner {
                 // if desugar of `do yeet`, don't lint
                 if let ExprKind::Call(path_expr, _) = inner_expr.kind
-                    && let ExprKind::Path(QPath::LangItem(LangItem::TryTraitFromYeet, _, _)) = path_expr.kind
+                    && let ExprKind::Path(QPath::LangItem(LangItem::TryTraitFromYeet, ..)) = path_expr.kind
                 {
                     return;
                 }

src/tools/clippy/clippy_lints/src/unnecessary_map_on_constructor.rs

@@ -59,7 +59,7 @@ impl<'tcx> LateLintPass<'tcx> for UnnecessaryMapOnConstructor {
                     }
                 },
                 hir::QPath::TypeRelative(_, path) => path.ident.name,
-                hir::QPath::LangItem(_, _, _) => return,
+                hir::QPath::LangItem(..) => return,
             };
             match constructor_symbol {
                 sym::Some | sym::Ok if path.ident.name == rustc_span::sym::map => (),