Name change Import to Use in hir-def, add unused placeholder variants for UseId

crates/hir-def/src/attr.rs

@@ -485,6 +485,7 @@ impl AttrsWithOwner {
             },
             AttrDefId::ExternBlockId(it) => attrs_from_item_tree_loc(db, it),
             AttrDefId::ExternCrateId(it) => attrs_from_item_tree_loc(db, it),
+            AttrDefId::UseId(it) => attrs_from_item_tree_loc(db, it),
         };
 
         let attrs = raw_attrs.filter(db.upcast(), def.krate(db));
@@ -570,6 +571,7 @@ impl AttrsWithOwner {
             },
             AttrDefId::ExternBlockId(id) => any_has_attrs(db, id),
             AttrDefId::ExternCrateId(id) => any_has_attrs(db, id),
+            AttrDefId::UseId(id) => any_has_attrs(db, id),
         };
 
         AttrSourceMap::new(owner.as_ref().map(|node| node as &dyn HasAttrs))

crates/hir-def/src/child_by_source.rs

@@ -15,7 +15,7 @@ use crate::{
     nameres::DefMap,
     src::{HasChildSource, HasSource},
     AdtId, AssocItemId, DefWithBodyId, EnumId, EnumVariantId, ExternCrateId, FieldId, ImplId,
-    Lookup, MacroId, ModuleDefId, ModuleId, TraitId, VariantId,
+    Lookup, MacroId, ModuleDefId, ModuleId, TraitId, UseId, VariantId,
 };
 
 pub trait ChildBySource {
@@ -92,6 +92,7 @@ impl ChildBySource for ItemScope {
         self.declarations().for_each(|item| add_module_def(db, res, file_id, item));
         self.impls().for_each(|imp| add_impl(db, res, file_id, imp));
         self.extern_crate_decls().for_each(|ext| add_extern_crate(db, res, file_id, ext));
+        self.use_decls().for_each(|ext| add_use(db, res, file_id, ext));
         self.unnamed_consts().for_each(|konst| {
             let loc = konst.lookup(db);
             if loc.id.file_id() == file_id {
@@ -179,6 +180,12 @@ impl ChildBySource for ItemScope {
                 map[keys::EXTERN_CRATE].insert(loc.source(db).value, ext)
             }
         }
+        fn add_use(db: &dyn DefDatabase, map: &mut DynMap, file_id: HirFileId, ext: UseId) {
+            let loc = ext.lookup(db);
+            if loc.id.file_id() == file_id {
+                map[keys::USE].insert(loc.source(db).value, ext)
+            }
+        }
     }
 }
 

crates/hir-def/src/db.rs

@@ -23,17 +23,17 @@ use crate::{
     visibility::{self, Visibility},
     AttrDefId, BlockId, BlockLoc, ConstBlockId, ConstBlockLoc, ConstId, ConstLoc, DefWithBodyId,
     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,
+    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, UseId, UseLoc, VariantId,
 };
 
 #[salsa::query_group(InternDatabaseStorage)]
 pub trait InternDatabase: SourceDatabase {
     // region: items
     #[salsa::interned]
-    fn intern_import(&self, loc: ImportLoc) -> ImportId;
+    fn intern_use(&self, loc: UseLoc) -> UseId;
     #[salsa::interned]
     fn intern_extern_crate(&self, loc: ExternCrateLoc) -> ExternCrateId;
     #[salsa::interned]

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

@@ -10,7 +10,7 @@ use crate::{
     dyn_map::{DynMap, Policy},
     ConstId, EnumId, EnumVariantId, ExternCrateId, FieldId, FunctionId, ImplId, LifetimeParamId,
     Macro2Id, MacroRulesId, ProcMacroId, StaticId, StructId, TraitAliasId, TraitId, TypeAliasId,
-    TypeOrConstParamId, UnionId,
+    TypeOrConstParamId, UnionId, UseId,
 };
 
 pub type Key<K, V> = crate::dyn_map::Key<K, V, AstPtrPolicy<K, V>>;
@@ -26,6 +26,7 @@ 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 USE: Key<ast::Use, UseId> = 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

@@ -16,6 +16,7 @@ use syntax::ast;
 use crate::{
     db::DefDatabase, per_ns::PerNs, visibility::Visibility, AdtId, BuiltinType, ConstId,
     ExternCrateId, HasModule, ImplId, LocalModuleId, MacroId, ModuleDefId, ModuleId, TraitId,
+    UseId,
 };
 
 #[derive(Copy, Clone, Debug)]
@@ -119,6 +120,11 @@ impl ItemScope {
         self.extern_crate_decls.iter().copied()
     }
 
+    pub fn use_decls(&self) -> impl Iterator<Item = UseId> + ExactSizeIterator + '_ {
+        // FIXME: to be implemented
+        std::iter::empty()
+    }
+
     pub fn impls(&self) -> impl Iterator<Item = ImplId> + ExactSizeIterator + '_ {
         self.impls.iter().copied()
     }

crates/hir-def/src/item_tree.rs

@@ -188,7 +188,7 @@ impl ItemTree {
     fn shrink_to_fit(&mut self) {
         if let Some(data) = &mut self.data {
             let ItemTreeData {
-                imports,
+                uses,
                 extern_crates,
                 extern_blocks,
                 functions,
@@ -211,7 +211,7 @@ impl ItemTree {
                 vis,
             } = &mut **data;
 
-            imports.shrink_to_fit();
+            uses.shrink_to_fit();
             extern_crates.shrink_to_fit();
             extern_blocks.shrink_to_fit();
             functions.shrink_to_fit();
@@ -262,7 +262,7 @@ static VIS_PUB_CRATE: RawVisibility = RawVisibility::Module(ModPath::from_kind(P
 
 #[derive(Default, Debug, Eq, PartialEq)]
 struct ItemTreeData {
-    imports: Arena<Import>,
+    uses: Arena<Use>,
     extern_crates: Arena<ExternCrate>,
     extern_blocks: Arena<ExternBlock>,
     functions: Arena<Function>,
@@ -486,7 +486,7 @@ macro_rules! mod_items {
 }
 
 mod_items! {
-    Import in imports -> ast::Use,
+    Use in uses -> ast::Use,
     ExternCrate in extern_crates -> ast::ExternCrate,
     ExternBlock in extern_blocks -> ast::ExternBlock,
     Function in functions -> ast::Fn,
@@ -541,7 +541,7 @@ impl<N: ItemTreeNode> Index<FileItemTreeId<N>> for ItemTree {
 }
 
 #[derive(Debug, Clone, Eq, PartialEq)]
-pub struct Import {
+pub struct Use {
     pub visibility: RawVisibilityId,
     pub ast_id: FileAstId<ast::Use>,
     pub use_tree: UseTree,
@@ -744,7 +744,7 @@ pub struct MacroDef {
     pub ast_id: FileAstId<ast::MacroDef>,
 }
 
-impl Import {
+impl Use {
     /// Maps a `UseTree` contained in this import back to its AST node.
     pub fn use_tree_to_ast(
         &self,
@@ -870,7 +870,7 @@ macro_rules! impl_froms {
 impl ModItem {
     pub fn as_assoc_item(&self) -> Option<AssocItem> {
         match self {
-            ModItem::Import(_)
+            ModItem::Use(_)
             | ModItem::ExternCrate(_)
             | ModItem::ExternBlock(_)
             | ModItem::Struct(_)
@@ -892,7 +892,7 @@ impl ModItem {
 
     pub fn ast_id(&self, tree: &ItemTree) -> FileAstId<ast::Item> {
         match self {
-            ModItem::Import(it) => tree[it.index].ast_id().upcast(),
+            ModItem::Use(it) => tree[it.index].ast_id().upcast(),
             ModItem::ExternCrate(it) => tree[it.index].ast_id().upcast(),
             ModItem::ExternBlock(it) => tree[it.index].ast_id().upcast(),
             ModItem::Function(it) => tree[it.index].ast_id().upcast(),

crates/hir-def/src/item_tree/lower.rs

@@ -502,13 +502,13 @@ impl<'a> Ctx<'a> {
         Some(id(self.data().impls.alloc(res)))
     }
 
-    fn lower_use(&mut self, use_item: &ast::Use) -> Option<FileItemTreeId<Import>> {
+    fn lower_use(&mut self, use_item: &ast::Use) -> Option<FileItemTreeId<Use>> {
         let visibility = self.lower_visibility(use_item);
         let ast_id = self.source_ast_id_map.ast_id(use_item);
         let (use_tree, _) = lower_use_tree(self.db, self.hygiene(), use_item.use_tree()?)?;
 
-        let res = Import { visibility, ast_id, use_tree };
-        Some(id(self.data().imports.alloc(res)))
+        let res = Use { visibility, ast_id, use_tree };
+        Some(id(self.data().uses.alloc(res)))
     }
 
     fn lower_extern_crate(

crates/hir-def/src/item_tree/pretty.rs

@@ -198,8 +198,8 @@ impl Printer<'_> {
         self.print_attrs_of(item);
 
         match item {
-            ModItem::Import(it) => {
-                let Import { visibility, use_tree, ast_id: _ } = &self.tree[it];
+            ModItem::Use(it) => {
+                let Use { visibility, use_tree, ast_id: _ } = &self.tree[it];
                 self.print_visibility(*visibility);
                 w!(self, "use ");
                 self.print_use_tree(use_tree);

crates/hir-def/src/lib.rs

@@ -88,8 +88,8 @@ use crate::{
     builtin_type::BuiltinType,
     data::adt::VariantData,
     item_tree::{
-        Const, Enum, ExternCrate, Function, Impl, Import, ItemTreeId, ItemTreeNode, MacroDef,
-        MacroRules, Static, Struct, Trait, TraitAlias, TypeAlias, Union,
+        Const, Enum, ExternCrate, Function, Impl, ItemTreeId, ItemTreeNode, MacroDef, MacroRules,
+        Static, Struct, Trait, TraitAlias, TypeAlias, Union, Use,
     },
 };
 
@@ -324,9 +324,9 @@ 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);
+pub struct UseId(salsa::InternId);
+type UseLoc = ItemLoc<Use>;
+impl_intern!(UseId, UseLoc, intern_use, lookup_intern_use);
 
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash, Ord, PartialOrd)]
 pub struct ExternCrateId(salsa::InternId);
@@ -842,6 +842,7 @@ pub enum AttrDefId {
     GenericParamId(GenericParamId),
     ExternBlockId(ExternBlockId),
     ExternCrateId(ExternCrateId),
+    UseId(UseId),
 }
 
 impl_from!(
@@ -1079,6 +1080,7 @@ impl AttrDefId {
             }
             AttrDefId::MacroId(it) => it.module(db).krate,
             AttrDefId::ExternCrateId(it) => it.lookup(db).container.krate,
+            AttrDefId::UseId(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, 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,
+    ExternBlockLoc, ExternCrateLoc, FunctionId, FunctionLoc, ImplLoc, Intern, ItemContainerId,
+    LocalModuleId, Macro2Id, Macro2Loc, MacroExpander, MacroId, MacroRulesId, MacroRulesLoc,
+    ModuleDefId, ModuleId, ProcMacroId, ProcMacroLoc, StaticLoc, StructLoc, TraitAliasLoc,
+    TraitLoc, TypeAliasLoc, UnionLoc, UnresolvedMacro, UseLoc,
 };
 
 static GLOB_RECURSION_LIMIT: Limit = Limit::new(100);
@@ -146,7 +146,7 @@ impl PartialResolvedImport {
 
 #[derive(Clone, Debug, Eq, PartialEq)]
 enum ImportSource {
-    Import { id: ItemTreeId<item_tree::Import>, use_tree: Idx<ast::UseTree> },
+    Use { id: ItemTreeId<item_tree::Use>, use_tree: Idx<ast::UseTree> },
     ExternCrate(ItemTreeId<item_tree::ExternCrate>),
 }
 
@@ -166,7 +166,7 @@ impl Import {
         db: &dyn DefDatabase,
         krate: CrateId,
         tree: &ItemTree,
-        id: ItemTreeId<item_tree::Import>,
+        id: ItemTreeId<item_tree::Use>,
         mut cb: impl FnMut(Self),
     ) {
         let it = &tree[id.value];
@@ -181,7 +181,7 @@ impl Import {
                 kind,
                 is_prelude,
                 is_macro_use: false,
-                source: ImportSource::Import { id, use_tree: idx },
+                source: ImportSource::Use { id, use_tree: idx },
             });
         });
     }
@@ -1474,7 +1474,7 @@ impl DefCollector<'_> {
         }
 
         for directive in &self.unresolved_imports {
-            if let ImportSource::Import { id: import, use_tree } = directive.import.source {
+            if let ImportSource::Use { id: import, use_tree } = directive.import.source {
                 if matches!(
                     (directive.import.path.segments().first(), &directive.import.path.kind),
                     (Some(krate), PathKind::Plain | PathKind::Abs) if diagnosed_extern_crates.contains(krate)
@@ -1576,12 +1576,10 @@ impl ModCollector<'_, '_> {
 
             match item {
                 ModItem::Mod(m) => self.collect_module(m, &attrs),
-                ModItem::Import(import_id) => {
-                    let _import_id = ImportLoc {
-                        container: module,
-                        id: ItemTreeId::new(self.tree_id, import_id),
-                    }
-                    .intern(db);
+                ModItem::Use(import_id) => {
+                    let _import_id =
+                        UseLoc { container: module, id: ItemTreeId::new(self.tree_id, import_id) }
+                            .intern(db);
                     Import::from_use(
                         db,
                         krate,

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

@@ -19,7 +19,7 @@ pub enum DefDiagnosticKind {
 
     UnresolvedExternCrate { ast: AstId<ast::ExternCrate> },
 
-    UnresolvedImport { id: ItemTreeId<item_tree::Import>, index: Idx<ast::UseTree> },
+    UnresolvedImport { id: ItemTreeId<item_tree::Use>, index: Idx<ast::UseTree> },
 
     UnconfiguredCode { ast: ErasedAstId, cfg: CfgExpr, opts: CfgOptions },
 
@@ -70,7 +70,7 @@ impl DefDiagnostic {
 
     pub(super) fn unresolved_import(
         container: LocalModuleId,
-        id: ItemTreeId<item_tree::Import>,
+        id: ItemTreeId<item_tree::Use>,
         index: Idx<ast::UseTree>,
     ) -> Self {
         Self { in_module: container, kind: DefDiagnosticKind::UnresolvedImport { id, index } }

crates/hir-def/src/resolver.rs

@@ -25,7 +25,7 @@ use crate::{
     EnumVariantId, ExternBlockId, ExternCrateId, FunctionId, GenericDefId, GenericParamId,
     HasModule, ImplId, ItemContainerId, LifetimeParamId, LocalModuleId, Lookup, Macro2Id, MacroId,
     MacroRulesId, ModuleDefId, ModuleId, ProcMacroId, StaticId, StructId, TraitAliasId, TraitId,
-    TypeAliasId, TypeOrConstParamId, TypeOwnerId, TypeParamId, VariantId,
+    TypeAliasId, TypeOrConstParamId, TypeOwnerId, TypeParamId, UseId, VariantId,
 };
 
 #[derive(Debug, Clone)]
@@ -1024,6 +1024,12 @@ impl HasResolver for ExternCrateId {
     }
 }
 
+impl HasResolver for UseId {
+    fn resolver(self, db: &dyn DefDatabase) -> Resolver {
+        self.lookup(db).container.resolver(db)
+    }
+}
+
 impl HasResolver for TypeOwnerId {
     fn resolver(self, db: &dyn DefDatabase) -> Resolver {
         match self {

crates/hir-ty/src/diagnostics/decl_check.rs

@@ -176,6 +176,7 @@ impl<'a> DeclValidator<'a> {
                 AttrDefId::ImplId(iid) => Some(iid.lookup(self.db.upcast()).container.into()),
                 AttrDefId::ExternBlockId(id) => Some(id.lookup(self.db.upcast()).container.into()),
                 AttrDefId::ExternCrateId(id) =>  Some(id.lookup(self.db.upcast()).container.into()),
+                AttrDefId::UseId(id) =>  Some(id.lookup(self.db.upcast()).container.into()),
                 // These warnings should not explore macro definitions at all
                 AttrDefId::MacroId(_) => None,
                 AttrDefId::AdtId(aid) => match aid {

crates/hir/src/attrs.rs

@@ -173,6 +173,7 @@ fn resolve_doc_path(
         AttrDefId::TypeAliasId(it) => it.resolver(db.upcast()),
         AttrDefId::ImplId(it) => it.resolver(db.upcast()),
         AttrDefId::ExternBlockId(it) => it.resolver(db.upcast()),
+        AttrDefId::UseId(it) => it.resolver(db.upcast()),
         AttrDefId::MacroId(it) => it.resolver(db.upcast()),
         AttrDefId::ExternCrateId(it) => it.resolver(db.upcast()),
         AttrDefId::GenericParamId(it) => match it {

crates/hir/src/semantics/source_to_def.rs

@@ -95,7 +95,7 @@ use hir_def::{
     hir::{BindingId, LabelId},
     AdtId, ConstId, ConstParamId, DefWithBodyId, EnumId, EnumVariantId, ExternCrateId, FieldId,
     FunctionId, GenericDefId, GenericParamId, ImplId, LifetimeParamId, MacroId, ModuleId, StaticId,
-    StructId, TraitAliasId, TraitId, TypeAliasId, TypeParamId, UnionId, VariantId,
+    StructId, TraitAliasId, TraitId, TypeAliasId, TypeParamId, UnionId, UseId, VariantId,
 };
 use hir_expand::{attrs::AttrId, name::AsName, HirFileId, MacroCallId};
 use rustc_hash::FxHashMap;
@@ -209,6 +209,10 @@ impl SourceToDefCtx<'_, '_> {
     ) -> Option<ExternCrateId> {
         self.to_def(src, keys::EXTERN_CRATE)
     }
+    #[allow(dead_code)]
+    pub(super) fn use_to_def(&mut self, src: InFile<ast::Use>) -> Option<UseId> {
+        self.to_def(src, keys::USE)
+    }
     pub(super) fn adt_to_def(
         &mut self,
         InFile { file_id, value }: InFile<ast::Adt>,