fix: Do not show safety hints for extern items lacking semantics

crates/hir/src/from_id.rs

@@ -49,6 +49,7 @@ from_id![
     (hir_def::LifetimeParamId, crate::LifetimeParam),
     (hir_def::MacroId, crate::Macro),
     (hir_def::ExternCrateId, crate::ExternCrateDecl),
+    (hir_def::ExternBlockId, crate::ExternBlock),
 ];
 
 impl From<AdtId> for Adt {

crates/hir/src/lib.rs

@@ -55,8 +55,8 @@ use hir_def::{
     resolver::{HasResolver, Resolver},
     type_ref::TypesSourceMap,
     AdtId, AssocItemId, AssocItemLoc, AttrDefId, CallableDefId, ConstId, ConstParamId,
-    CrateRootModuleId, DefWithBodyId, EnumId, EnumVariantId, ExternCrateId, FunctionId,
-    GenericDefId, GenericParamId, HasModule, ImplId, InTypeConstId, ItemContainerId,
+    CrateRootModuleId, DefWithBodyId, EnumId, EnumVariantId, ExternBlockId, ExternCrateId,
+    FunctionId, GenericDefId, GenericParamId, HasModule, ImplId, InTypeConstId, ItemContainerId,
     LifetimeParamId, LocalFieldId, Lookup, MacroExpander, MacroId, ModuleId, StaticId, StructId,
     SyntheticSyntax, TraitAliasId, TupleId, TypeAliasId, TypeOrConstParamId, TypeParamId, UnionId,
 };
@@ -2327,6 +2327,13 @@ impl Function {
         db.function_data(self.id).is_async()
     }
 
+    pub fn extern_block(self, db: &dyn HirDatabase) -> Option<ExternBlock> {
+        match self.id.lookup(db.upcast()).container {
+            ItemContainerId::ExternBlockId(id) => Some(ExternBlock { id }),
+            _ => None,
+        }
+    }
+
     pub fn returns_impl_future(self, db: &dyn HirDatabase) -> bool {
         if self.is_async(db) {
             return true;
@@ -2761,6 +2768,13 @@ impl Static {
         Type::from_value_def(db, self.id)
     }
 
+    pub fn extern_block(self, db: &dyn HirDatabase) -> Option<ExternBlock> {
+        match self.id.lookup(db.upcast()).container {
+            ItemContainerId::ExternBlockId(id) => Some(ExternBlock { id }),
+            _ => None,
+        }
+    }
+
     /// Evaluate the static initializer.
     pub fn eval(self, db: &dyn HirDatabase) -> Result<EvaluatedConst, ConstEvalError> {
         db.const_eval(self.id.into(), Substitution::empty(Interner), None)
@@ -2928,6 +2942,17 @@ impl HasVisibility for TypeAlias {
     }
 }
 
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
+pub struct ExternBlock {
+    pub(crate) id: ExternBlockId,
+}
+
+impl ExternBlock {
+    pub fn module(self, db: &dyn HirDatabase) -> Module {
+        Module { id: self.id.module(db.upcast()) }
+    }
+}
+
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
 pub struct StaticLifetime;
 
@@ -6180,9 +6205,15 @@ impl HasContainer for TraitAlias {
     }
 }
 
+impl HasContainer for ExternBlock {
+    fn container(&self, db: &dyn HirDatabase) -> ItemContainer {
+        ItemContainer::Module(Module { id: self.id.lookup(db.upcast()).container })
+    }
+}
+
 fn container_id_to_hir(c: ItemContainerId) -> ItemContainer {
     match c {
-        ItemContainerId::ExternBlockId(_id) => ItemContainer::ExternBlock(),
+        ItemContainerId::ExternBlockId(id) => ItemContainer::ExternBlock(ExternBlock { id }),
         ItemContainerId::ModuleId(id) => ItemContainer::Module(Module { id }),
         ItemContainerId::ImplId(id) => ItemContainer::Impl(Impl { id }),
         ItemContainerId::TraitId(id) => ItemContainer::Trait(Trait { id }),
@@ -6194,7 +6225,7 @@ pub enum ItemContainer {
     Trait(Trait),
     Impl(Impl),
     Module(Module),
-    ExternBlock(),
+    ExternBlock(ExternBlock),
     Crate(CrateId),
 }
 

crates/hir/src/semantics.rs

@@ -1998,6 +1998,7 @@ to_def_impls![
     (crate::Adt, ast::Adt, adt_to_def),
     (crate::ExternCrateDecl, ast::ExternCrate, extern_crate_to_def),
     (crate::InlineAsmOperand, ast::AsmOperandNamed, asm_operand_to_def),
+    (crate::ExternBlock, ast::ExternBlock, extern_block_to_def),
     (MacroCallId, ast::MacroCall, macro_call_to_macro_call),
 ];
 

crates/hir/src/semantics/child_by_source.rs

@@ -74,6 +74,9 @@ impl ChildBySource for ItemScope {
     fn child_by_source_to(&self, db: &dyn DefDatabase, res: &mut DynMap, file_id: HirFileId) {
         self.declarations().for_each(|item| add_module_def(db, res, file_id, item));
         self.impls().for_each(|imp| insert_item_loc(db, res, file_id, imp, keys::IMPL));
+        self.extern_blocks().for_each(|extern_block| {
+            insert_item_loc(db, res, file_id, extern_block, keys::EXTERN_BLOCK)
+        });
         self.extern_crate_decls()
             .for_each(|ext| insert_item_loc(db, res, file_id, ext, keys::EXTERN_CRATE));
         self.use_decls().for_each(|ext| insert_item_loc(db, res, file_id, ext, keys::USE));

crates/hir/src/semantics/source_to_def.rs

@@ -92,10 +92,10 @@ use hir_def::{
         DynMap,
     },
     hir::{BindingId, Expr, LabelId},
-    AdtId, BlockId, ConstId, ConstParamId, DefWithBodyId, EnumId, EnumVariantId, ExternCrateId,
-    FieldId, FunctionId, GenericDefId, GenericParamId, ImplId, LifetimeParamId, Lookup, MacroId,
-    ModuleId, StaticId, StructId, TraitAliasId, TraitId, TypeAliasId, TypeParamId, UnionId, UseId,
-    VariantId,
+    AdtId, BlockId, ConstId, ConstParamId, DefWithBodyId, EnumId, EnumVariantId, ExternBlockId,
+    ExternCrateId, FieldId, FunctionId, GenericDefId, GenericParamId, ImplId, LifetimeParamId,
+    Lookup, MacroId, ModuleId, StaticId, StructId, TraitAliasId, TraitId, TypeAliasId, TypeParamId,
+    UnionId, UseId, VariantId,
 };
 use hir_expand::{
     attrs::AttrId, name::AsName, ExpansionInfo, HirFileId, HirFileIdExt, InMacroFile, MacroCallId,
@@ -308,6 +308,12 @@ impl SourceToDefCtx<'_, '_> {
     ) -> Option<ExternCrateId> {
         self.to_def(src, keys::EXTERN_CRATE)
     }
+    pub(super) fn extern_block_to_def(
+        &mut self,
+        src: InFile<&ast::ExternBlock>,
+    ) -> Option<ExternBlockId> {
+        self.to_def(src, keys::EXTERN_BLOCK)
+    }
     #[allow(dead_code)]
     pub(super) fn use_to_def(&mut self, src: InFile<&ast::Use>) -> Option<UseId> {
         self.to_def(src, keys::USE)