internal: Intern use and extern crate items like other items

crates/hir-def/src/attr.rs

@@ -462,6 +462,7 @@ impl AttrsWithOwner {
                 }
             },
             AttrDefId::ExternBlockId(it) => attrs_from_item_tree_loc(db, it),
+            AttrDefId::ExternCrateId(it) => attrs_from_item_tree_loc(db, it),
         };
 
         let attrs = raw_attrs.filter(db.upcast(), def.krate(db));
@@ -546,6 +547,7 @@ impl AttrsWithOwner {
                     .map(|source| ast::AnyHasAttrs::new(source[id.local_id].clone())),
             },
             AttrDefId::ExternBlockId(id) => any_has_attrs(db, id),
+            AttrDefId::ExternCrateId(id) => any_has_attrs(db, id),
         };
 
         AttrSourceMap::new(owner.as_ref().map(|node| node as &dyn HasAttrs))

crates/hir-def/src/data.rs

@@ -24,11 +24,12 @@ use crate::{
         proc_macro::{parse_macro_name_and_helper_attrs, ProcMacroKind},
         DefMap, MacroSubNs,
     },
+    path::ImportAlias,
     type_ref::{TraitRef, TypeBound, TypeRef},
     visibility::RawVisibility,
-    AssocItemId, AstIdWithPath, ConstId, ConstLoc, FunctionId, FunctionLoc, HasModule, ImplId,
-    Intern, ItemContainerId, ItemLoc, Lookup, Macro2Id, MacroRulesId, ModuleId, ProcMacroId,
-    StaticId, TraitAliasId, TraitId, TypeAliasId, TypeAliasLoc,
+    AssocItemId, AstIdWithPath, ConstId, ConstLoc, ExternCrateId, FunctionId, FunctionLoc,
+    HasModule, ImplId, Intern, ItemContainerId, ItemLoc, Lookup, Macro2Id, MacroRulesId, ModuleId,
+    ProcMacroId, StaticId, TraitAliasId, TraitId, TypeAliasId, TypeAliasLoc,
 };
 
 #[derive(Debug, Clone, PartialEq, Eq)]
@@ -424,6 +425,7 @@ impl MacroRulesData {
         Arc::new(MacroRulesData { name: makro.name.clone(), macro_export })
     }
 }
+
 #[derive(Debug, Clone, PartialEq, Eq)]
 pub struct ProcMacroData {
     pub name: Name,
@@ -460,6 +462,30 @@ impl ProcMacroData {
     }
 }
 
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct ExternCrateDeclData {
+    pub name: Name,
+    pub alias: Option<ImportAlias>,
+    pub visibility: RawVisibility,
+}
+
+impl ExternCrateDeclData {
+    pub(crate) fn extern_crate_decl_data_query(
+        db: &dyn DefDatabase,
+        extern_crate: ExternCrateId,
+    ) -> Arc<ExternCrateDeclData> {
+        let loc = extern_crate.lookup(db);
+        let item_tree = loc.id.item_tree(db);
+        let extern_crate = &item_tree[loc.id.value];
+
+        Arc::new(Self {
+            name: extern_crate.name.clone(),
+            visibility: item_tree[extern_crate.visibility].clone(),
+            alias: extern_crate.alias.clone(),
+        })
+    }
+}
+
 #[derive(Debug, Clone, PartialEq, Eq)]
 pub struct ConstData {
     /// `None` for `const _: () = ();`

crates/hir-def/src/db.rs

@@ -12,8 +12,8 @@ use crate::{
     body::{scope::ExprScopes, Body, BodySourceMap},
     data::{
         adt::{EnumData, StructData},
-        ConstData, FunctionData, ImplData, Macro2Data, MacroRulesData, ProcMacroData, StaticData,
-        TraitAliasData, TraitData, TypeAliasData,
+        ConstData, ExternCrateDeclData, FunctionData, ImplData, Macro2Data, MacroRulesData,
+        ProcMacroData, StaticData, TraitAliasData, TraitData, TypeAliasData,
     },
     generics::GenericParams,
     import_map::ImportMap,
@@ -22,17 +22,21 @@ use crate::{
     nameres::{diagnostics::DefDiagnostic, DefMap},
     visibility::{self, Visibility},
     AttrDefId, BlockId, BlockLoc, ConstBlockId, ConstBlockLoc, ConstId, ConstLoc, DefWithBodyId,
-    EnumId, EnumLoc, ExternBlockId, ExternBlockLoc, FunctionId, FunctionLoc, GenericDefId, ImplId,
-    ImplLoc, InTypeConstId, InTypeConstLoc, LocalEnumVariantId, LocalFieldId, Macro2Id, Macro2Loc,
-    MacroRulesId, MacroRulesLoc, ProcMacroId, ProcMacroLoc, StaticId, StaticLoc, StructId,
-    StructLoc, TraitAliasId, TraitAliasLoc, TraitId, TraitLoc, TypeAliasId, TypeAliasLoc, UnionId,
-    UnionLoc, VariantId,
+    EnumId, EnumLoc, ExternBlockId, ExternBlockLoc, ExternCrateId, ExternCrateLoc, FunctionId,
+    FunctionLoc, GenericDefId, ImplId, ImplLoc, ImportId, ImportLoc, InTypeConstId, InTypeConstLoc,
+    LocalEnumVariantId, LocalFieldId, Macro2Id, Macro2Loc, MacroRulesId, MacroRulesLoc,
+    ProcMacroId, ProcMacroLoc, StaticId, StaticLoc, StructId, StructLoc, TraitAliasId,
+    TraitAliasLoc, TraitId, TraitLoc, TypeAliasId, TypeAliasLoc, UnionId, UnionLoc, VariantId,
 };
 
 #[salsa::query_group(InternDatabaseStorage)]
 pub trait InternDatabase: SourceDatabase {
     // region: items
     #[salsa::interned]
+    fn intern_import(&self, loc: ImportLoc) -> ImportId;
+    #[salsa::interned]
+    fn intern_extern_crate(&self, loc: ExternCrateLoc) -> ExternCrateId;
+    #[salsa::interned]
     fn intern_function(&self, loc: FunctionLoc) -> FunctionId;
     #[salsa::interned]
     fn intern_struct(&self, loc: StructLoc) -> StructId;
@@ -160,6 +164,9 @@ pub trait DefDatabase: InternDatabase + ExpandDatabase + Upcast<dyn ExpandDataba
     #[salsa::invoke(ProcMacroData::proc_macro_data_query)]
     fn proc_macro_data(&self, makro: ProcMacroId) -> Arc<ProcMacroData>;
 
+    #[salsa::invoke(ExternCrateDeclData::extern_crate_decl_data_query)]
+    fn extern_crate_decl_data(&self, extern_crate: ExternCrateId) -> Arc<ExternCrateDeclData>;
+
     // endregion:data
 
     #[salsa::invoke(Body::body_with_source_map_query)]

crates/hir-def/src/dyn_map/keys.rs

@@ -8,8 +8,8 @@ use syntax::{ast, AstNode, AstPtr};
 
 use crate::{
     dyn_map::{DynMap, Policy},
-    ConstId, EnumId, EnumVariantId, FieldId, FunctionId, ImplId, LifetimeParamId, Macro2Id,
-    MacroRulesId, ProcMacroId, StaticId, StructId, TraitAliasId, TraitId, TypeAliasId,
+    ConstId, EnumId, EnumVariantId, ExternCrateId, FieldId, FunctionId, ImplId, LifetimeParamId,
+    Macro2Id, MacroRulesId, ProcMacroId, StaticId, StructId, TraitAliasId, TraitId, TypeAliasId,
     TypeOrConstParamId, UnionId,
 };
 
@@ -25,6 +25,7 @@ pub const TRAIT_ALIAS: Key<ast::TraitAlias, TraitAliasId> = Key::new();
 pub const STRUCT: Key<ast::Struct, StructId> = Key::new();
 pub const UNION: Key<ast::Union, UnionId> = Key::new();
 pub const ENUM: Key<ast::Enum, EnumId> = Key::new();
+pub const EXTERN_CRATE: Key<ast::ExternCrate, ExternCrateId> = Key::new();
 
 pub const VARIANT: Key<ast::Variant, EnumVariantId> = Key::new();
 pub const TUPLE_FIELD: Key<ast::TupleField, FieldId> = Key::new();

crates/hir-def/src/item_scope.rs

@@ -14,8 +14,8 @@ use stdx::format_to;
 use syntax::ast;
 
 use crate::{
-    db::DefDatabase, per_ns::PerNs, visibility::Visibility, AdtId, BuiltinType, ConstId, HasModule,
-    ImplId, LocalModuleId, MacroId, ModuleDefId, ModuleId, TraitId,
+    db::DefDatabase, per_ns::PerNs, visibility::Visibility, AdtId, BuiltinType, ConstId,
+    ExternCrateId, HasModule, ImplId, LocalModuleId, MacroId, ModuleDefId, ModuleId, TraitId,
 };
 
 #[derive(Copy, Clone, Debug)]
@@ -50,6 +50,7 @@ pub struct ItemScope {
     unnamed_consts: Vec<ConstId>,
     /// Traits imported via `use Trait as _;`.
     unnamed_trait_imports: FxHashMap<TraitId, Visibility>,
+    extern_crate_decls: Vec<ExternCrateId>,
     /// Macros visible in current module in legacy textual scope
     ///
     /// For macros invoked by an unqualified identifier like `bar!()`, `legacy_macros` will be searched in first.
@@ -188,7 +189,11 @@ impl ItemScope {
     }
 
     pub(crate) fn define_impl(&mut self, imp: ImplId) {
-        self.impls.push(imp)
+        self.impls.push(imp);
+    }
+
+    pub(crate) fn define_extern_crate_decl(&mut self, extern_crate: ExternCrateId) {
+        self.extern_crate_decls.push(extern_crate);
     }
 
     pub(crate) fn define_unnamed_const(&mut self, konst: ConstId) {
@@ -397,6 +402,7 @@ impl ItemScope {
             legacy_macros,
             attr_macros,
             derive_macros,
+            extern_crate_decls,
         } = self;
         types.shrink_to_fit();
         values.shrink_to_fit();
@@ -409,6 +415,7 @@ impl ItemScope {
         legacy_macros.shrink_to_fit();
         attr_macros.shrink_to_fit();
         derive_macros.shrink_to_fit();
+        extern_crate_decls.shrink_to_fit();
     }
 }
 

crates/hir-def/src/lib.rs

@@ -88,8 +88,8 @@ use crate::{
     builtin_type::BuiltinType,
     data::adt::VariantData,
     item_tree::{
-        Const, Enum, Function, Impl, ItemTreeId, ItemTreeNode, MacroDef, MacroRules, Static,
-        Struct, Trait, TraitAlias, TypeAlias, Union,
+        Const, Enum, ExternCrate, Function, Impl, Import, ItemTreeId, ItemTreeNode, MacroDef,
+        MacroRules, Static, Struct, Trait, TraitAlias, TypeAlias, Union,
     },
 };
 
@@ -313,6 +313,16 @@ pub struct ImplId(salsa::InternId);
 type ImplLoc = ItemLoc<Impl>;
 impl_intern!(ImplId, ImplLoc, intern_impl, lookup_intern_impl);
 
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash, Ord, PartialOrd)]
+pub struct ImportId(salsa::InternId);
+type ImportLoc = ItemLoc<Import>;
+impl_intern!(ImportId, ImportLoc, intern_import, lookup_intern_import);
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash, Ord, PartialOrd)]
+pub struct ExternCrateId(salsa::InternId);
+type ExternCrateLoc = ItemLoc<ExternCrate>;
+impl_intern!(ExternCrateId, ExternCrateLoc, intern_extern_crate, lookup_intern_extern_crate);
+
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash, Ord, PartialOrd)]
 pub struct ExternBlockId(salsa::InternId);
 type ExternBlockLoc = ItemLoc<ExternBlock>;
@@ -821,6 +831,7 @@ pub enum AttrDefId {
     ImplId(ImplId),
     GenericParamId(GenericParamId),
     ExternBlockId(ExternBlockId),
+    ExternCrateId(ExternCrateId),
 }
 
 impl_from!(
@@ -835,7 +846,8 @@ impl_from!(
     TypeAliasId,
     MacroId(Macro2Id, MacroRulesId, ProcMacroId),
     ImplId,
-    GenericParamId
+    GenericParamId,
+    ExternCrateId
     for AttrDefId
 );
 
@@ -927,6 +939,12 @@ impl HasModule for AdtId {
     }
 }
 
+impl HasModule for ExternCrateId {
+    fn module(&self, db: &dyn db::DefDatabase) -> ModuleId {
+        self.lookup(db).container
+    }
+}
+
 impl HasModule for VariantId {
     fn module(&self, db: &dyn db::DefDatabase) -> ModuleId {
         match self {
@@ -1050,6 +1068,7 @@ impl AttrDefId {
                 .krate
             }
             AttrDefId::MacroId(it) => it.module(db).krate,
+            AttrDefId::ExternCrateId(it) => it.lookup(db).container.krate,
         }
     }
 }

crates/hir-def/src/nameres/collector.rs

@@ -52,10 +52,10 @@ use crate::{
     tt,
     visibility::{RawVisibility, Visibility},
     AdtId, AstId, AstIdWithPath, ConstLoc, CrateRootModuleId, EnumLoc, EnumVariantId,
-    ExternBlockLoc, FunctionId, FunctionLoc, ImplLoc, Intern, ItemContainerId, LocalModuleId,
-    Macro2Id, Macro2Loc, MacroExpander, MacroId, MacroRulesId, MacroRulesLoc, ModuleDefId,
-    ModuleId, ProcMacroId, ProcMacroLoc, StaticLoc, StructLoc, TraitAliasLoc, TraitLoc,
-    TypeAliasLoc, UnionLoc, UnresolvedMacro,
+    ExternBlockLoc, ExternCrateLoc, FunctionId, FunctionLoc, ImplLoc, ImportLoc, Intern,
+    ItemContainerId, LocalModuleId, Macro2Id, Macro2Loc, MacroExpander, MacroId, MacroRulesId,
+    MacroRulesLoc, ModuleDefId, ModuleId, ProcMacroId, ProcMacroLoc, StaticLoc, StructLoc,
+    TraitAliasLoc, TraitLoc, TypeAliasLoc, UnionLoc, UnresolvedMacro,
 };
 
 static GLOB_RECURSION_LIMIT: Limit = Limit::new(100);
@@ -156,10 +156,9 @@ struct Import {
     alias: Option<ImportAlias>,
     visibility: RawVisibility,
     kind: ImportKind,
+    source: ImportSource,
     is_prelude: bool,
-    is_extern_crate: bool,
     is_macro_use: bool,
-    source: ImportSource,
 }
 
 impl Import {
@@ -168,26 +167,23 @@ impl Import {
         krate: CrateId,
         tree: &ItemTree,
         id: ItemTreeId<item_tree::Import>,
-    ) -> Vec<Self> {
+        mut cb: impl FnMut(Self),
+    ) {
         let it = &tree[id.value];
         let attrs = &tree.attrs(db, krate, ModItem::from(id.value).into());
         let visibility = &tree[it.visibility];
         let is_prelude = attrs.by_key("prelude_import").exists();
-
-        let mut res = Vec::new();
         it.use_tree.expand(|idx, path, kind, alias| {
-            res.push(Self {
+            cb(Self {
                 path,
                 alias,
                 visibility: visibility.clone(),
                 kind,
                 is_prelude,
-                is_extern_crate: false,
                 is_macro_use: false,
                 source: ImportSource::Import { id, use_tree: idx },
             });
         });
-        res
     }
 
     fn from_extern_crate(
@@ -205,7 +201,6 @@ impl Import {
             visibility: visibility.clone(),
             kind: ImportKind::Plain,
             is_prelude: false,
-            is_extern_crate: true,
             is_macro_use: attrs.by_key("macro_use").exists(),
             source: ImportSource::ExternCrate(id),
         }
@@ -776,7 +771,7 @@ impl DefCollector<'_> {
         let _p = profile::span("resolve_import")
             .detail(|| format!("{}", import.path.display(self.db.upcast())));
         tracing::debug!("resolving import: {:?} ({:?})", import, self.def_map.data.edition);
-        if import.is_extern_crate {
+        if matches!(import.source, ImportSource::ExternCrate { .. }) {
             let name = import
                 .path
                 .as_ident()
@@ -867,7 +862,7 @@ impl DefCollector<'_> {
                 tracing::debug!("resolved import {:?} ({:?}) to {:?}", name, import, def);
 
                 // extern crates in the crate root are special-cased to insert entries into the extern prelude: rust-lang/rust#54658
-                if import.is_extern_crate
+                if matches!(import.source, ImportSource::ExternCrate { .. })
                     && self.def_map.block.is_none()
                     && module_id == DefMap::ROOT
                 {
@@ -1585,21 +1580,34 @@ impl ModCollector<'_, '_> {
             match item {
                 ModItem::Mod(m) => self.collect_module(m, &attrs),
                 ModItem::Import(import_id) => {
-                    let imports = Import::from_use(
+                    let _import_id = ImportLoc {
+                        container: module,
+                        id: ItemTreeId::new(self.tree_id, import_id),
+                    }
+                    .intern(db);
+                    Import::from_use(
                         db,
                         krate,
                         self.item_tree,
                         ItemTreeId::new(self.tree_id, import_id),
-                    );
-                    self.def_collector.unresolved_imports.extend(imports.into_iter().map(
-                        |import| ImportDirective {
-                            module_id: self.module_id,
-                            import,
-                            status: PartialResolvedImport::Unresolved,
+                        |import| {
+                            self.def_collector.unresolved_imports.push(ImportDirective {
+                                module_id: self.module_id,
+                                import,
+                                status: PartialResolvedImport::Unresolved,
+                            });
                         },
-                    ));
+                    )
                 }
                 ModItem::ExternCrate(import_id) => {
+                    let extern_crate_id = ExternCrateLoc {
+                        container: module,
+                        id: ItemTreeId::new(self.tree_id, import_id),
+                    }
+                    .intern(db);
+                    self.def_collector.def_map.modules[self.module_id]
+                        .scope
+                        .define_extern_crate_decl(extern_crate_id);
                     self.def_collector.unresolved_imports.push(ImportDirective {
                         module_id: self.module_id,
                         import: Import::from_extern_crate(