Implement def_ident_span in rustc_middle.

Author: cjgillot

compiler/rustc_middle/src/hir/map/mod.rs

@@ -910,27 +910,34 @@ impl<'hir> Map<'hir> {
         }
     }
 
+    pub(super) fn opt_ident_span(self, id: HirId) -> Option<Span> {
+        let ident = match self.get(id) {
+            // A `Ctor` doesn't have an identifier itself, but its parent
+            // struct/variant does. Compare with `hir::Map::opt_span`.
+            Node::Ctor(..) => match self.find(self.get_parent_node(id))? {
+                Node::Item(item) => Some(item.ident),
+                Node::Variant(variant) => Some(variant.ident),
+                _ => unreachable!(),
+            },
+            node => node.ident(),
+        };
+        ident.map(|ident| ident.span)
+    }
+
     pub fn opt_name(self, id: HirId) -> Option<Symbol> {
-        Some(match self.get(id) {
-            Node::Item(i) => i.ident.name,
-            Node::ForeignItem(fi) => fi.ident.name,
-            Node::ImplItem(ii) => ii.ident.name,
-            Node::TraitItem(ti) => ti.ident.name,
-            Node::Variant(v) => v.ident.name,
-            Node::Field(f) => f.ident.name,
-            Node::Lifetime(lt) => lt.name.ident().name,
-            Node::GenericParam(param) => param.name.ident().name,
-            Node::Binding(&Pat { kind: PatKind::Binding(_, _, l, _), .. }) => l.name,
-            Node::Ctor(..) => self.name(HirId::make_owner(self.get_parent_item(id))),
-            _ => return None,
-        })
+        match self.get(id) {
+            Node::Binding(&Pat { kind: PatKind::Binding(_, _, l, _), .. }) => Some(l.name),
+            Node::Ctor(..) => match self.find(self.get_parent_node(id))? {
+                Node::Item(item) => Some(item.ident.name),
+                Node::Variant(variant) => Some(variant.ident.name),
+                _ => unreachable!(),
+            },
+            node => node.ident().map(|i| i.name),
+        }
     }
 
     pub fn name(self, id: HirId) -> Symbol {
-        match self.opt_name(id) {
-            Some(name) => name,
-            None => bug!("no name for {}", self.node_to_string(id)),
-        }
+        self.opt_name(id).unwrap_or_else(|| bug!("no name for {}", self.node_to_string(id)))
     }
 
     /// Given a node ID, gets a list of attributes associated with the AST

compiler/rustc_middle/src/hir/mod.rs

@@ -122,6 +122,11 @@ pub fn provide(providers: &mut Providers) {
         |tcx, id| tcx.hir_crate(()).owners[id].as_owner().map_or(AttributeMap::EMPTY, |o| &o.attrs);
     providers.source_span = |tcx, def_id| tcx.resolutions(()).definitions.def_span(def_id);
     providers.def_span = |tcx, def_id| tcx.hir().span_if_local(def_id).unwrap_or(DUMMY_SP);
+    providers.def_ident_span = |tcx, def_id| {
+        let def_id = def_id.expect_local();
+        let hir_id = tcx.hir().local_def_id_to_hir_id(def_id);
+        tcx.hir().opt_ident_span(hir_id)
+    };
     providers.fn_arg_names = |tcx, id| {
         let hir = tcx.hir();
         let hir_id = hir.local_def_id_to_hir_id(id.expect_local());

compiler/rustc_ty_utils/src/ty.rs

@@ -5,7 +5,6 @@ use rustc_middle::ty::subst::Subst;
 use rustc_middle::ty::{
     self, Binder, EarlyBinder, Predicate, PredicateKind, ToPredicate, Ty, TyCtxt,
 };
-use rustc_span::Span;
 use rustc_trait_selection::traits;
 
 fn sized_constraint_for_ty<'tcx>(
@@ -103,21 +102,6 @@ fn adt_sized_constraint(tcx: TyCtxt<'_>, def_id: DefId) -> ty::AdtSizedConstrain
     ty::AdtSizedConstraint(result)
 }
 
-fn def_ident_span(tcx: TyCtxt<'_>, def_id: DefId) -> Option<Span> {
-    tcx.hir()
-        .get_if_local(def_id)
-        .and_then(|node| match node {
-            // A `Ctor` doesn't have an identifier itself, but its parent
-            // struct/variant does. Compare with `hir::Map::opt_span`.
-            hir::Node::Ctor(ctor) => ctor
-                .ctor_hir_id()
-                .and_then(|ctor_id| tcx.hir().find(tcx.hir().get_parent_node(ctor_id)))
-                .and_then(|parent| parent.ident()),
-            _ => node.ident(),
-        })
-        .map(|ident| ident.span)
-}
-
 /// See `ParamEnv` struct definition for details.
 #[instrument(level = "debug", skip(tcx))]
 fn param_env(tcx: TyCtxt<'_>, def_id: DefId) -> ty::ParamEnv<'_> {
@@ -480,7 +464,6 @@ pub fn provide(providers: &mut ty::query::Providers) {
     *providers = ty::query::Providers {
         asyncness,
         adt_sized_constraint,
-        def_ident_span,
         param_env,
         param_env_reveal_all_normalized,
         instance_def_size_estimate,