Centralize const item lowering logic

Author: camelid

compiler/rustc_ast_lowering/src/item.rs

@@ -170,15 +170,16 @@ impl<'hir> LoweringContext<'_, 'hir> {
             }
             ItemKind::Static(box ast::StaticItem {
                 ident,
-                ty: t,
+                ty,
                 safety: _,
                 mutability: m,
                 expr: e,
                 define_opaque,
             }) => {
                 let ident = self.lower_ident(*ident);
-                let (ty, body_id) =
-                    self.lower_const_item(t, span, e.as_deref(), ImplTraitPosition::StaticTy);
+                let ty =
+                    self.lower_ty(ty, ImplTraitContext::Disallowed(ImplTraitPosition::StaticTy));
+                let body_id = self.lower_const_body(span, e.as_deref());
                 self.lower_define_opaque(hir_id, define_opaque);
                 hir::ItemKind::Static(ident, ty, *m, body_id)
             }
@@ -196,7 +197,9 @@ impl<'hir> LoweringContext<'_, 'hir> {
                     id,
                     ImplTraitContext::Disallowed(ImplTraitPosition::Generic),
                     |this| {
-                        this.lower_const_item(ty, span, expr.as_deref(), ImplTraitPosition::ConstTy)
+                        let ty = this
+                            .lower_ty(ty, ImplTraitContext::Disallowed(ImplTraitPosition::ConstTy));
+                        (ty, this.lower_const_item(span, expr.as_deref()))
                     },
                 );
                 self.lower_define_opaque(hir_id, &define_opaque);
@@ -480,15 +483,23 @@ impl<'hir> LoweringContext<'_, 'hir> {
         }
     }
 
-    fn lower_const_item(
-        &mut self,
-        ty: &Ty,
-        span: Span,
-        body: Option<&Expr>,
-        impl_trait_position: ImplTraitPosition,
-    ) -> (&'hir hir::Ty<'hir>, hir::BodyId) {
-        let ty = self.lower_ty(ty, ImplTraitContext::Disallowed(impl_trait_position));
-        (ty, self.lower_const_body(span, body))
+    fn lower_const_item(&mut self, span: Span, body: Option<&Expr>) -> hir::BodyId {
+        self.lower_const_body(span, body)
+        // TODO: code to add next
+        // let ct_arg = if self.tcx.features().min_generic_const_args()
+        //     && let Some(expr) = body
+        // {
+        //     self.try_lower_as_const_path(expr)
+        // } else {
+        //     None
+        // };
+        // let body_id = if body.is_some() && ct_arg.is_none() {
+        //     // TODO: lower as const block instead
+        //     self.lower_const_body(span, body)
+        // } else {
+        //     self.lower_const_body(span, body)
+        // };
+        // (body_id, ct_arg)
     }
 
     #[instrument(level = "debug", skip(self))]
@@ -797,8 +808,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
                     |this| {
                         let ty = this
                             .lower_ty(ty, ImplTraitContext::Disallowed(ImplTraitPosition::ConstTy));
-                        let body = expr.as_ref().map(|x| this.lower_const_body(i.span, Some(x)));
-
+                        let body = expr.as_deref().map(|e| this.lower_const_item(i.span, Some(e)));
                         hir::TraitItemKind::Const(ty, body)
                     },
                 );
@@ -990,8 +1000,8 @@ impl<'hir> LoweringContext<'_, 'hir> {
                     |this| {
                         let ty = this
                             .lower_ty(ty, ImplTraitContext::Disallowed(ImplTraitPosition::ConstTy));
-                        let body = this.lower_const_body(i.span, expr.as_deref());
                         this.lower_define_opaque(hir_id, &define_opaque);
+                        let body = this.lower_const_item(i.span, expr.as_deref());
                         hir::ImplItemKind::Const(ty, body)
                     },
                 ),