Infallible version of def_span.

Author: cjgillot

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

@@ -848,50 +848,55 @@ impl<'hir> Map<'hir> {
     /// Gets the span of the definition of the specified HIR node.
     /// This is used by `tcx.get_span`
     pub fn span(&self, hir_id: HirId) -> Span {
-        match self.find_entry(hir_id).map(|entry| entry.node) {
-            Some(Node::Param(param)) => param.span,
-            Some(Node::Item(item)) => match &item.kind {
+        self.opt_span(hir_id)
+            .unwrap_or_else(|| bug!("hir::map::Map::span: id not in map: {:?}", hir_id))
+    }
+
+    pub fn opt_span(&self, hir_id: HirId) -> Option<Span> {
+        let span = match self.find_entry(hir_id)?.node {
+            Node::Param(param) => param.span,
+            Node::Item(item) => match &item.kind {
                 ItemKind::Fn(sig, _, _) => sig.span,
                 _ => item.span,
             },
-            Some(Node::ForeignItem(foreign_item)) => foreign_item.span,
-            Some(Node::TraitItem(trait_item)) => match &trait_item.kind {
+            Node::ForeignItem(foreign_item) => foreign_item.span,
+            Node::TraitItem(trait_item) => match &trait_item.kind {
                 TraitItemKind::Fn(sig, _) => sig.span,
                 _ => trait_item.span,
             },
-            Some(Node::ImplItem(impl_item)) => match &impl_item.kind {
+            Node::ImplItem(impl_item) => match &impl_item.kind {
                 ImplItemKind::Fn(sig, _) => sig.span,
                 _ => impl_item.span,
             },
-            Some(Node::Variant(variant)) => variant.span,
-            Some(Node::Field(field)) => field.span,
-            Some(Node::AnonConst(constant)) => self.body(constant.body).value.span,
-            Some(Node::Expr(expr)) => expr.span,
-            Some(Node::Stmt(stmt)) => stmt.span,
-            Some(Node::PathSegment(seg)) => seg.ident.span,
-            Some(Node::Ty(ty)) => ty.span,
-            Some(Node::TraitRef(tr)) => tr.path.span,
-            Some(Node::Binding(pat)) => pat.span,
-            Some(Node::Pat(pat)) => pat.span,
-            Some(Node::Arm(arm)) => arm.span,
-            Some(Node::Block(block)) => block.span,
-            Some(Node::Ctor(..)) => match self.find(self.get_parent_node(hir_id)) {
-                Some(Node::Item(item)) => item.span,
-                Some(Node::Variant(variant)) => variant.span,
+            Node::Variant(variant) => variant.span,
+            Node::Field(field) => field.span,
+            Node::AnonConst(constant) => self.body(constant.body).value.span,
+            Node::Expr(expr) => expr.span,
+            Node::Stmt(stmt) => stmt.span,
+            Node::PathSegment(seg) => seg.ident.span,
+            Node::Ty(ty) => ty.span,
+            Node::TraitRef(tr) => tr.path.span,
+            Node::Binding(pat) => pat.span,
+            Node::Pat(pat) => pat.span,
+            Node::Arm(arm) => arm.span,
+            Node::Block(block) => block.span,
+            Node::Ctor(..) => match self.find(self.get_parent_node(hir_id))? {
+                Node::Item(item) => item.span,
+                Node::Variant(variant) => variant.span,
                 _ => unreachable!(),
             },
-            Some(Node::Lifetime(lifetime)) => lifetime.span,
-            Some(Node::GenericParam(param)) => param.span,
-            Some(Node::Visibility(&Spanned {
+            Node::Lifetime(lifetime) => lifetime.span,
+            Node::GenericParam(param) => param.span,
+            Node::Visibility(&Spanned {
                 node: VisibilityKind::Restricted { ref path, .. },
                 ..
-            })) => path.span,
-            Some(Node::Visibility(v)) => bug!("unexpected Visibility {:?}", v),
-            Some(Node::Local(local)) => local.span,
-            Some(Node::MacroDef(macro_def)) => macro_def.span,
-            Some(Node::Crate(item)) => item.span,
-            None => bug!("hir::map::Map::span: id not in map: {:?}", hir_id),
-        }
+            }) => path.span,
+            Node::Visibility(v) => bug!("unexpected Visibility {:?}", v),
+            Node::Local(local) => local.span,
+            Node::MacroDef(macro_def) => macro_def.span,
+            Node::Crate(item) => item.span,
+        };
+        Some(span)
     }
 
     /// Like `hir.span()`, but includes the body of function items
@@ -907,7 +912,7 @@ impl<'hir> Map<'hir> {
     }
 
     pub fn span_if_local(&self, id: DefId) -> Option<Span> {
-        id.as_local().map(|id| self.span(self.local_def_id_to_hir_id(id)))
+        id.as_local().and_then(|id| self.opt_span(self.local_def_id_to_hir_id(id)))
     }
 
     pub fn res_span(&self, res: Res) -> Option<Span> {

compiler/rustc_middle/src/hir/mod.rs

@@ -15,6 +15,7 @@ use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
 use rustc_hir::def_id::{LocalDefId, LOCAL_CRATE};
 use rustc_hir::*;
 use rustc_index::vec::IndexVec;
+use rustc_span::DUMMY_SP;
 
 pub struct Owner<'tcx> {
     parent: HirId,
@@ -77,6 +78,7 @@ pub fn provide(providers: &mut Providers) {
     };
     providers.hir_owner = |tcx, id| tcx.index_hir(LOCAL_CRATE).map[id].signature;
     providers.hir_owner_nodes = |tcx, id| tcx.index_hir(LOCAL_CRATE).map[id].with_bodies.as_deref();
+    providers.def_span = |tcx, def_id| tcx.hir().span_if_local(def_id).unwrap_or(DUMMY_SP);
     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

@@ -218,10 +218,6 @@ fn associated_items(tcx: TyCtxt<'_>, def_id: DefId) -> ty::AssociatedItems<'_> {
     ty::AssociatedItems::new(items)
 }
 
-fn def_span(tcx: TyCtxt<'_>, def_id: DefId) -> Span {
-    tcx.hir().span_if_local(def_id).unwrap()
-}
-
 fn def_ident_span(tcx: TyCtxt<'_>, def_id: DefId) -> Option<Span> {
     tcx.hir().get_if_local(def_id).and_then(|node| node.ident()).map(|ident| ident.span)
 }
@@ -495,7 +491,6 @@ pub fn provide(providers: &mut ty::query::Providers) {
         associated_item_def_ids,
         associated_items,
         adt_sized_constraint,
-        def_span,
         def_ident_span,
         param_env,
         param_env_reveal_all_normalized,