1 //! The core of the module-level name resolution algorithm.
3 //! `DefCollector::collect` contains the fixed-point iteration loop which
4 //! resolves imports and expands macros.
8 use base_db::{CrateId, Edition, FileId, ProcMacroId};
9 use cfg::{CfgExpr, CfgOptions};
11 ast_id_map::FileAstId,
12 builtin_attr_macro::{find_builtin_attr, is_builtin_test_or_bench_attr},
13 builtin_derive_macro::find_builtin_derive,
14 builtin_fn_macro::find_builtin_macro,
15 name::{name, AsName, Name},
16 proc_macro::ProcMacroExpander,
17 ExpandTo, HirFileId, MacroCallId, MacroCallKind, MacroDefId, MacroDefKind,
19 use hir_expand::{InFile, MacroCallLoc};
20 use itertools::Itertools;
23 use rustc_hash::{FxHashMap, FxHashSet};
24 use syntax::{ast, SmolStr};
27 attr::{Attr, AttrId, AttrInput, Attrs},
28 attr_macro_as_call_id, builtin_attr,
30 derive_macro_as_call_id,
32 item_scope::{ImportType, PerNsGlobImports},
34 self, Fields, FileItemTreeId, ImportKind, ItemTree, ItemTreeId, MacroCall, MacroDef,
35 MacroRules, Mod, ModItem, ModKind, TreeId,
37 macro_call_as_call_id,
39 diagnostics::DefDiagnostic,
40 mod_resolution::ModDir,
41 path_resolution::ReachedFixedPoint,
42 proc_macro::{ProcMacroDef, ProcMacroKind},
43 BuiltinShadowMode, DefMap, ModuleData, ModuleOrigin, ResolveMode,
45 path::{ImportAlias, ModPath, PathKind},
47 visibility::{RawVisibility, Visibility},
48 AdtId, AstId, AstIdWithPath, ConstLoc, EnumLoc, EnumVariantId, FunctionLoc, ImplLoc, Intern,
49 LocalModuleId, ModuleDefId, StaticLoc, StructLoc, TraitLoc, TypeAliasLoc, UnionLoc,
53 static GLOB_RECURSION_LIMIT: Limit = Limit::new(100);
54 static EXPANSION_DEPTH_LIMIT: Limit = Limit::new(128);
55 static FIXED_POINT_LIMIT: Limit = Limit::new(8192);
57 pub(super) fn collect_defs(
60 block: Option<AstId<ast::BlockExpr>>,
62 let crate_graph = db.crate_graph();
64 let mut deps = FxHashMap::default();
65 // populate external prelude and dependency list
66 for dep in &crate_graph[def_map.krate].dependencies {
67 tracing::debug!("crate dep {:?} -> {:?}", dep.name, dep.crate_id);
68 let dep_def_map = db.crate_def_map(dep.crate_id);
69 let dep_root = dep_def_map.module_id(dep_def_map.root);
71 deps.insert(dep.as_name(), dep_root.into());
73 if dep.is_prelude() && block.is_none() {
74 def_map.extern_prelude.insert(dep.as_name(), dep_root.into());
78 let cfg_options = &crate_graph[def_map.krate].cfg_options;
79 let proc_macros = &crate_graph[def_map.krate].proc_macro;
80 let proc_macros = proc_macros
84 // FIXME: a hacky way to create a Name from string.
85 let name = tt::Ident { text: it.name.clone(), id: tt::TokenId::unspecified() };
86 (name.as_name(), ProcMacroExpander::new(def_map.krate, ProcMacroId(idx as u32)))
90 let mut collector = DefCollector {
94 glob_imports: FxHashMap::default(),
95 unresolved_imports: Vec::new(),
96 resolved_imports: Vec::new(),
97 unresolved_macros: Vec::new(),
98 mod_dirs: FxHashMap::default(),
101 exports_proc_macros: false,
102 from_glob_import: Default::default(),
103 skip_attrs: Default::default(),
104 derive_helpers_in_scope: Default::default(),
105 registered_attrs: Default::default(),
106 registered_tools: Default::default(),
109 Some(block) => collector.seed_with_inner(block),
110 None => collector.seed_with_top_level(),
113 let mut def_map = collector.finish();
114 def_map.shrink_to_fit();
118 #[derive(Copy, Clone, Debug, Eq, PartialEq)]
119 enum PartialResolvedImport {
120 /// None of any namespaces is resolved
122 /// One of namespaces is resolved
123 Indeterminate(PerNs),
124 /// All namespaces are resolved, OR it comes from other crate
128 impl PartialResolvedImport {
129 fn namespaces(self) -> PerNs {
131 PartialResolvedImport::Unresolved => PerNs::none(),
132 PartialResolvedImport::Indeterminate(ns) | PartialResolvedImport::Resolved(ns) => ns,
137 #[derive(Clone, Debug, Eq, PartialEq)]
139 Import { id: ItemTreeId<item_tree::Import>, use_tree: Idx<ast::UseTree> },
140 ExternCrate(ItemTreeId<item_tree::ExternCrate>),
143 #[derive(Clone, Debug, Eq, PartialEq)]
145 path: Interned<ModPath>,
146 alias: Option<ImportAlias>,
147 visibility: RawVisibility,
150 is_extern_crate: bool,
152 source: ImportSource,
157 db: &dyn DefDatabase,
160 id: ItemTreeId<item_tree::Import>,
162 let it = &tree[id.value];
163 let attrs = &tree.attrs(db, krate, ModItem::from(id.value).into());
164 let visibility = &tree[it.visibility];
165 let is_prelude = attrs.by_key("prelude_import").exists();
167 let mut res = Vec::new();
168 it.use_tree.expand(|idx, path, kind, alias| {
170 path: Interned::new(path), // FIXME this makes little sense
172 visibility: visibility.clone(),
175 is_extern_crate: false,
177 source: ImportSource::Import { id, use_tree: idx },
183 fn from_extern_crate(
184 db: &dyn DefDatabase,
187 id: ItemTreeId<item_tree::ExternCrate>,
189 let it = &tree[id.value];
190 let attrs = &tree.attrs(db, krate, ModItem::from(id.value).into());
191 let visibility = &tree[it.visibility];
193 path: Interned::new(ModPath::from_segments(
195 iter::once(it.name.clone()),
197 alias: it.alias.clone(),
198 visibility: visibility.clone(),
199 kind: ImportKind::Plain,
201 is_extern_crate: true,
202 is_macro_use: attrs.by_key("macro_use").exists(),
203 source: ImportSource::ExternCrate(id),
208 #[derive(Clone, Debug, Eq, PartialEq)]
209 struct ImportDirective {
210 module_id: LocalModuleId,
212 status: PartialResolvedImport,
215 #[derive(Clone, Debug, Eq, PartialEq)]
216 struct MacroDirective {
217 module_id: LocalModuleId,
219 kind: MacroDirectiveKind,
222 #[derive(Clone, Debug, Eq, PartialEq)]
223 enum MacroDirectiveKind {
224 FnLike { ast_id: AstIdWithPath<ast::MacroCall>, expand_to: ExpandTo },
225 Derive { ast_id: AstIdWithPath<ast::Item>, derive_attr: AttrId },
226 Attr { ast_id: AstIdWithPath<ast::Item>, attr: Attr, mod_item: ModItem },
232 visibility: &'a RawVisibility,
233 has_constructor: bool,
236 /// Walks the tree of module recursively
237 struct DefCollector<'a> {
238 db: &'a dyn DefDatabase,
240 deps: FxHashMap<Name, ModuleDefId>,
241 glob_imports: FxHashMap<LocalModuleId, Vec<(LocalModuleId, Visibility)>>,
242 unresolved_imports: Vec<ImportDirective>,
243 resolved_imports: Vec<ImportDirective>,
244 unresolved_macros: Vec<MacroDirective>,
245 mod_dirs: FxHashMap<LocalModuleId, ModDir>,
246 cfg_options: &'a CfgOptions,
247 /// List of procedural macros defined by this crate. This is read from the dynamic library
248 /// built by the build system, and is the list of proc. macros we can actually expand. It is
249 /// empty when proc. macro support is disabled (in which case we still do name resolution for
251 proc_macros: Vec<(Name, ProcMacroExpander)>,
252 exports_proc_macros: bool,
253 from_glob_import: PerNsGlobImports,
254 /// If we fail to resolve an attribute on a `ModItem`, we fall back to ignoring the attribute.
255 /// This map is used to skip all attributes up to and including the one that failed to resolve,
256 /// in order to not expand them twice.
258 /// This also stores the attributes to skip when we resolve derive helpers and non-macro
259 /// non-builtin attributes in general.
260 skip_attrs: FxHashMap<InFile<ModItem>, AttrId>,
261 /// Tracks which custom derives are in scope for an item, to allow resolution of derive helper
263 derive_helpers_in_scope: FxHashMap<AstId<ast::Item>, Vec<Name>>,
264 /// Custom attributes registered with `#![register_attr]`.
265 registered_attrs: Vec<SmolStr>,
266 /// Custom tool modules registered with `#![register_tool]`.
267 registered_tools: Vec<SmolStr>,
270 impl DefCollector<'_> {
271 fn seed_with_top_level(&mut self) {
272 let _p = profile::span("seed_with_top_level");
274 let file_id = self.db.crate_graph()[self.def_map.krate].root_file_id;
275 let item_tree = self.db.file_item_tree(file_id.into());
276 let module_id = self.def_map.root;
278 let attrs = item_tree.top_level_attrs(self.db, self.def_map.krate);
279 if attrs.cfg().map_or(true, |cfg| self.cfg_options.check(&cfg) != Some(false)) {
280 self.inject_prelude(&attrs);
282 // Process other crate-level attributes.
283 for attr in &*attrs {
284 let attr_name = match attr.path.as_ident() {
289 let attr_is_register_like = *attr_name == hir_expand::name![register_attr]
290 || *attr_name == hir_expand::name![register_tool];
291 if !attr_is_register_like {
295 let registered_name = match attr.input.as_deref() {
296 Some(AttrInput::TokenTree(subtree, _)) => match &*subtree.token_trees {
297 [tt::TokenTree::Leaf(tt::Leaf::Ident(name))] => name.as_name(),
303 if *attr_name == hir_expand::name![register_attr] {
304 self.registered_attrs.push(registered_name.to_smol_str());
305 cov_mark::hit!(register_attr);
307 self.registered_tools.push(registered_name.to_smol_str());
308 cov_mark::hit!(register_tool);
316 tree_id: TreeId::new(file_id.into(), None),
317 item_tree: &item_tree,
318 mod_dir: ModDir::root(),
320 .collect(item_tree.top_level_items());
324 fn seed_with_inner(&mut self, block: AstId<ast::BlockExpr>) {
325 let item_tree = self.db.file_item_tree(block.file_id);
326 let module_id = self.def_map.root;
328 let is_cfg_enabled = item_tree
329 .top_level_attrs(self.db, self.def_map.krate)
331 .map_or(true, |cfg| self.cfg_options.check(&cfg) != Some(false));
337 // FIXME: populate block once we have per-block ItemTrees
338 tree_id: TreeId::new(block.file_id, None),
339 item_tree: &item_tree,
340 mod_dir: ModDir::root(),
342 .collect(item_tree.inner_items_of_block(block.value));
346 fn resolution_loop(&mut self) {
347 let _p = profile::span("DefCollector::resolution_loop");
349 // main name resolution fixed-point loop.
353 self.db.unwind_if_cancelled();
355 let _p = profile::span("resolve_imports loop");
357 if self.resolve_imports() == ReachedFixedPoint::Yes {
362 if self.resolve_macros() == ReachedFixedPoint::Yes {
367 if FIXED_POINT_LIMIT.check(i).is_err() {
368 tracing::error!("name resolution is stuck");
373 if self.reseed_with_unresolved_attribute() == ReachedFixedPoint::Yes {
379 fn collect(&mut self) {
380 let _p = profile::span("DefCollector::collect");
382 self.resolution_loop();
384 // Resolve all indeterminate resolved imports again
385 // As some of the macros will expand newly import shadowing partial resolved imports
386 // FIXME: We maybe could skip this, if we handle the indeterminate imports in `resolve_imports`
388 let partial_resolved = self.resolved_imports.iter().filter_map(|directive| {
389 if let PartialResolvedImport::Indeterminate(_) = directive.status {
390 let mut directive = directive.clone();
391 directive.status = PartialResolvedImport::Unresolved;
397 self.unresolved_imports.extend(partial_resolved);
398 self.resolve_imports();
400 let unresolved_imports = std::mem::take(&mut self.unresolved_imports);
401 // show unresolved imports in completion, etc
402 for directive in &unresolved_imports {
403 self.record_resolved_import(directive)
405 self.unresolved_imports = unresolved_imports;
407 // FIXME: This condition should instead check if this is a `proc-macro` type crate.
408 if self.exports_proc_macros {
409 // A crate exporting procedural macros is not allowed to export anything else.
411 // Additionally, while the proc macro entry points must be `pub`, they are not publicly
412 // exported in type/value namespace. This function reduces the visibility of all items
413 // in the crate root that aren't proc macros.
414 let root = self.def_map.root;
415 let module_id = self.def_map.module_id(root);
416 let root = &mut self.def_map.modules[root];
417 root.scope.censor_non_proc_macros(module_id);
421 /// When the fixed-point loop reaches a stable state, we might still have some unresolved
422 /// attributes (or unexpanded attribute proc macros) left over. This takes one of them, and
423 /// feeds the item it's applied to back into name resolution.
425 /// This effectively ignores the fact that the macro is there and just treats the items as
428 /// This improves UX when proc macros are turned off or don't work, and replicates the behavior
429 /// before we supported proc. attribute macros.
430 fn reseed_with_unresolved_attribute(&mut self) -> ReachedFixedPoint {
431 cov_mark::hit!(unresolved_attribute_fallback);
433 let mut unresolved_macros = std::mem::take(&mut self.unresolved_macros);
434 let pos = unresolved_macros.iter().position(|directive| {
435 if let MacroDirectiveKind::Attr { ast_id, mod_item, attr } = &directive.kind {
436 self.skip_attrs.insert(ast_id.ast_id.with_value(*mod_item), attr.id);
438 let file_id = ast_id.ast_id.file_id;
439 let item_tree = self.db.file_item_tree(file_id);
440 let mod_dir = self.mod_dirs[&directive.module_id].clone();
443 macro_depth: directive.depth,
444 module_id: directive.module_id,
445 tree_id: TreeId::new(file_id, None),
446 item_tree: &item_tree,
449 .collect(&[*mod_item]);
456 if let Some(pos) = pos {
457 unresolved_macros.remove(pos);
460 // The collection above might add new unresolved macros (eg. derives), so merge the lists.
461 self.unresolved_macros.extend(unresolved_macros);
464 // Continue name resolution with the new data.
465 ReachedFixedPoint::No
467 ReachedFixedPoint::Yes
471 fn inject_prelude(&mut self, crate_attrs: &Attrs) {
472 // See compiler/rustc_builtin_macros/src/standard_library_imports.rs
474 if crate_attrs.by_key("no_core").exists() {
475 // libcore does not get a prelude.
479 let krate = if crate_attrs.by_key("no_std").exists() {
482 let std = name![std];
483 if self.def_map.extern_prelude().any(|(name, _)| *name == std) {
486 // If `std` does not exist for some reason, fall back to core. This mostly helps
487 // keep r-a's own tests minimal.
492 let edition = match self.def_map.edition {
493 Edition::Edition2015 => name![rust_2015],
494 Edition::Edition2018 => name![rust_2018],
495 Edition::Edition2021 => name![rust_2021],
498 let path_kind = if self.def_map.edition == Edition::Edition2015 {
503 let path = ModPath::from_segments(
505 [krate.clone(), name![prelude], edition].into_iter(),
507 // Fall back to the older `std::prelude::v1` for compatibility with Rust <1.52.0
508 // FIXME remove this fallback
510 ModPath::from_segments(path_kind, [krate, name![prelude], name![v1]].into_iter());
512 for path in &[path, fallback_path] {
513 let (per_ns, _) = self.def_map.resolve_path(
517 BuiltinShadowMode::Other,
521 Some((ModuleDefId::ModuleId(m), _)) => {
522 self.def_map.prelude = Some(m);
527 "could not resolve prelude path `{}` to module (resolved to {:?})",
536 /// Adds a definition of procedural macro `name` to the root module.
538 /// # Notes on procedural macro resolution
540 /// Procedural macro functionality is provided by the build system: It has to build the proc
541 /// macro and pass the resulting dynamic library to rust-analyzer.
543 /// When procedural macro support is enabled, the list of proc macros exported by a crate is
544 /// known before we resolve names in the crate. This list is stored in `self.proc_macros` and is
545 /// derived from the dynamic library.
547 /// However, we *also* would like to be able to at least *resolve* macros on our own, without
548 /// help by the build system. So, when the macro isn't found in `self.proc_macros`, we instead
549 /// use a dummy expander that always errors. This comes with the drawback of macros potentially
550 /// going out of sync with what the build system sees (since we resolve using VFS state, but
551 /// Cargo builds only on-disk files). We could and probably should add diagnostics for that.
552 fn export_proc_macro(&mut self, def: ProcMacroDef, ast_id: AstId<ast::Fn>) {
553 let kind = def.kind.to_basedb_kind();
554 self.exports_proc_macros = true;
555 let macro_def = match self.proc_macros.iter().find(|(n, _)| n == &def.name) {
556 Some(&(_, expander)) => MacroDefId {
557 krate: self.def_map.krate,
558 kind: MacroDefKind::ProcMacro(expander, kind, ast_id),
562 krate: self.def_map.krate,
563 kind: MacroDefKind::ProcMacro(
564 ProcMacroExpander::dummy(self.def_map.krate),
572 self.define_proc_macro(def.name.clone(), macro_def);
573 self.def_map.exported_proc_macros.insert(macro_def, def);
576 /// Define a macro with `macro_rules`.
578 /// It will define the macro in legacy textual scope, and if it has `#[macro_export]`,
579 /// then it is also defined in the root module scope.
580 /// You can `use` or invoke it by `crate::macro_name` anywhere, before or after the definition.
582 /// It is surprising that the macro will never be in the current module scope.
583 /// These code fails with "unresolved import/macro",
584 /// ```rust,compile_fail
585 /// mod m { macro_rules! foo { () => {} } }
586 /// use m::foo as bar;
589 /// ```rust,compile_fail
590 /// macro_rules! foo { () => {} }
595 /// Well, this code compiles, because the plain path `foo` in `use` is searched
596 /// in the legacy textual scope only.
598 /// macro_rules! foo { () => {} }
601 fn define_macro_rules(
603 module_id: LocalModuleId,
609 self.define_legacy_macro(module_id, name.clone(), macro_);
612 // In Rust, `#[macro_export]` macros are unconditionally visible at the
613 // crate root, even if the parent modules is **not** visible.
617 &[(Some(name), PerNs::macros(macro_, Visibility::Public))],
624 /// Define a legacy textual scoped macro in module
626 /// We use a map `legacy_macros` to store all legacy textual scoped macros visible per module.
627 /// It will clone all macros from parent legacy scope, whose definition is prior to
628 /// the definition of current module.
629 /// And also, `macro_use` on a module will import all legacy macros visible inside to
630 /// current legacy scope, with possible shadowing.
631 fn define_legacy_macro(&mut self, module_id: LocalModuleId, name: Name, mac: MacroDefId) {
633 self.def_map.modules[module_id].scope.define_legacy_macro(name, mac);
636 /// Define a macro 2.0 macro
638 /// The scoped of macro 2.0 macro is equal to normal function
641 module_id: LocalModuleId,
647 self.def_map.resolve_visibility(self.db, module_id, vis).unwrap_or(Visibility::Public);
648 self.update(module_id, &[(Some(name), PerNs::macros(macro_, vis))], vis, ImportType::Named);
651 /// Define a proc macro
653 /// A proc macro is similar to normal macro scope, but it would not visible in legacy textual scoped.
654 /// And unconditionally exported.
655 fn define_proc_macro(&mut self, name: Name, macro_: MacroDefId) {
658 &[(Some(name), PerNs::macros(macro_, Visibility::Public))],
664 /// Import macros from `#[macro_use] extern crate`.
665 fn import_macros_from_extern_crate(
667 current_module_id: LocalModuleId,
668 extern_crate: &item_tree::ExternCrate,
671 "importing macros from extern crate: {:?} ({:?})",
673 self.def_map.edition,
676 let res = self.resolve_extern_crate(&extern_crate.name);
678 if let Some(ModuleDefId::ModuleId(m)) = res.take_types() {
679 if m == self.def_map.module_id(current_module_id) {
680 cov_mark::hit!(ignore_macro_use_extern_crate_self);
684 cov_mark::hit!(macro_rules_from_other_crates_are_visible_with_macro_use);
685 self.import_all_macros_exported(current_module_id, m.krate);
689 /// Import all exported macros from another crate
691 /// Exported macros are just all macros in the root module scope.
692 /// Note that it contains not only all `#[macro_export]` macros, but also all aliases
693 /// created by `use` in the root module, ignoring the visibility of `use`.
694 fn import_all_macros_exported(&mut self, current_module_id: LocalModuleId, krate: CrateId) {
695 let def_map = self.db.crate_def_map(krate);
696 for (name, def) in def_map[def_map.root].scope.macros() {
697 // `macro_use` only bring things into legacy scope.
698 self.define_legacy_macro(current_module_id, name.clone(), def);
702 /// Tries to resolve every currently unresolved import.
703 fn resolve_imports(&mut self) -> ReachedFixedPoint {
704 let mut res = ReachedFixedPoint::Yes;
705 let imports = std::mem::take(&mut self.unresolved_imports);
706 let imports = imports
708 .filter_map(|mut directive| {
709 directive.status = self.resolve_import(directive.module_id, &directive.import);
710 match directive.status {
711 PartialResolvedImport::Indeterminate(_) => {
712 self.record_resolved_import(&directive);
713 // FIXME: For avoid performance regression,
714 // we consider an imported resolved if it is indeterminate (i.e not all namespace resolved)
715 self.resolved_imports.push(directive);
716 res = ReachedFixedPoint::No;
719 PartialResolvedImport::Resolved(_) => {
720 self.record_resolved_import(&directive);
721 self.resolved_imports.push(directive);
722 res = ReachedFixedPoint::No;
725 PartialResolvedImport::Unresolved => Some(directive),
729 self.unresolved_imports = imports;
733 fn resolve_import(&self, module_id: LocalModuleId, import: &Import) -> PartialResolvedImport {
734 let _p = profile::span("resolve_import").detail(|| format!("{}", import.path));
735 tracing::debug!("resolving import: {:?} ({:?})", import, self.def_map.edition);
736 if import.is_extern_crate {
740 .expect("extern crate should have been desugared to one-element path");
742 let res = self.resolve_extern_crate(name);
745 PartialResolvedImport::Unresolved
747 PartialResolvedImport::Resolved(res)
750 let res = self.def_map.resolve_path_fp_with_macro(
755 BuiltinShadowMode::Module,
758 let def = res.resolved_def;
759 if res.reached_fixedpoint == ReachedFixedPoint::No || def.is_none() {
760 return PartialResolvedImport::Unresolved;
763 if let Some(krate) = res.krate {
764 if krate != self.def_map.krate {
765 return PartialResolvedImport::Resolved(
766 def.filter_visibility(|v| matches!(v, Visibility::Public)),
771 // Check whether all namespace is resolved
772 if def.take_types().is_some()
773 && def.take_values().is_some()
774 && def.take_macros().is_some()
776 PartialResolvedImport::Resolved(def)
778 PartialResolvedImport::Indeterminate(def)
783 fn resolve_extern_crate(&self, name: &Name) -> PerNs {
784 if name == &name!(self) {
785 cov_mark::hit!(extern_crate_self_as);
786 let root = match self.def_map.block {
788 let def_map = self.def_map.crate_root(self.db).def_map(self.db);
789 def_map.module_id(def_map.root())
791 None => self.def_map.module_id(self.def_map.root()),
793 PerNs::types(root.into(), Visibility::Public)
795 self.deps.get(name).map_or(PerNs::none(), |&it| PerNs::types(it, Visibility::Public))
799 fn record_resolved_import(&mut self, directive: &ImportDirective) {
800 let _p = profile::span("record_resolved_import");
802 let module_id = directive.module_id;
803 let import = &directive.import;
804 let mut def = directive.status.namespaces();
807 .resolve_visibility(self.db, module_id, &directive.import.visibility)
808 .unwrap_or(Visibility::Public);
811 ImportKind::Plain | ImportKind::TypeOnly => {
812 let name = match &import.alias {
813 Some(ImportAlias::Alias(name)) => Some(name),
814 Some(ImportAlias::Underscore) => None,
815 None => match import.path.segments().last() {
816 Some(last_segment) => Some(last_segment),
818 cov_mark::hit!(bogus_paths);
824 if import.kind == ImportKind::TypeOnly {
829 tracing::debug!("resolved import {:?} ({:?}) to {:?}", name, import, def);
831 // extern crates in the crate root are special-cased to insert entries into the extern prelude: rust-lang/rust#54658
832 if import.is_extern_crate && module_id == self.def_map.root {
833 if let (Some(def), Some(name)) = (def.take_types(), name) {
834 self.def_map.extern_prelude.insert(name.clone(), def);
838 self.update(module_id, &[(name.cloned(), def)], vis, ImportType::Named);
840 ImportKind::Glob => {
841 tracing::debug!("glob import: {:?}", import);
842 match def.take_types() {
843 Some(ModuleDefId::ModuleId(m)) => {
844 if import.is_prelude {
845 // Note: This dodgily overrides the injected prelude. The rustc
846 // implementation seems to work the same though.
847 cov_mark::hit!(std_prelude);
848 self.def_map.prelude = Some(m);
849 } else if m.krate != self.def_map.krate {
850 cov_mark::hit!(glob_across_crates);
851 // glob import from other crate => we can just import everything once
852 let item_map = m.def_map(self.db);
853 let scope = &item_map[m.local_id].scope;
855 // Module scoped macros is included
858 // only keep visible names...
860 (n, res.filter_visibility(|v| v.is_visible_from_other_crate()))
862 .filter(|(_, res)| !res.is_none())
863 .collect::<Vec<_>>();
865 self.update(module_id, &items, vis, ImportType::Glob);
867 // glob import from same crate => we do an initial
868 // import, and then need to propagate any further
871 let scope = if m.block == self.def_map.block_id() {
872 &self.def_map[m.local_id].scope
874 def_map = m.def_map(self.db);
875 &def_map[m.local_id].scope
878 // Module scoped macros is included
881 // only keep visible names...
885 res.filter_visibility(|v| {
886 v.is_visible_from_def_map(
894 .filter(|(_, res)| !res.is_none())
895 .collect::<Vec<_>>();
897 self.update(module_id, &items, vis, ImportType::Glob);
898 // record the glob import in case we add further items
899 let glob = self.glob_imports.entry(m.local_id).or_default();
900 if !glob.iter().any(|(mid, _)| *mid == module_id) {
901 glob.push((module_id, vis));
905 Some(ModuleDefId::AdtId(AdtId::EnumId(e))) => {
906 cov_mark::hit!(glob_enum);
907 // glob import from enum => just import all the variants
909 // XXX: urgh, so this works by accident! Here, we look at
910 // the enum data, and, in theory, this might require us to
911 // look back at the crate_def_map, creating a cycle. For
912 // example, `enum E { crate::some_macro!(); }`. Luckily, the
913 // only kind of macro that is allowed inside enum is a
914 // `cfg_macro`, and we don't need to run name resolution for
915 // it, but this is sheer luck!
916 let enum_data = self.db.enum_data(e);
917 let resolutions = enum_data
920 .map(|(local_id, variant_data)| {
921 let name = variant_data.name.clone();
922 let variant = EnumVariantId { parent: e, local_id };
923 let res = PerNs::both(variant.into(), variant.into(), vis);
926 .collect::<Vec<_>>();
927 self.update(module_id, &resolutions, vis, ImportType::Glob);
930 tracing::debug!("glob import {:?} from non-module/enum {:?}", import, d);
933 tracing::debug!("glob import {:?} didn't resolve as type", import);
942 module_id: LocalModuleId,
943 resolutions: &[(Option<Name>, PerNs)],
945 import_type: ImportType,
947 self.db.unwind_if_cancelled();
948 self.update_recursive(module_id, resolutions, vis, import_type, 0)
953 module_id: LocalModuleId,
954 resolutions: &[(Option<Name>, PerNs)],
955 // All resolutions are imported with this visibility; the visibilities in
956 // the `PerNs` values are ignored and overwritten
958 import_type: ImportType,
961 if GLOB_RECURSION_LIMIT.check(depth).is_err() {
962 // prevent stack overflows (but this shouldn't be possible)
963 panic!("infinite recursion in glob imports!");
965 let mut changed = false;
967 for (name, res) in resolutions {
970 let scope = &mut self.def_map.modules[module_id].scope;
971 changed |= scope.push_res_with_import(
972 &mut self.from_glob_import,
973 (module_id, name.clone()),
974 res.with_visibility(vis),
979 let tr = match res.take_types() {
980 Some(ModuleDefId::TraitId(tr)) => tr,
982 tracing::debug!("non-trait `_` import of {:?}", other);
987 let old_vis = self.def_map.modules[module_id].scope.unnamed_trait_vis(tr);
988 let should_update = match old_vis {
991 let max_vis = old_vis.max(vis, &self.def_map).unwrap_or_else(|| {
992 panic!("`Tr as _` imports with unrelated visibilities {:?} and {:?} (trait {:?})", old_vis, vis, tr);
995 if max_vis == old_vis {
998 cov_mark::hit!(upgrade_underscore_visibility);
1006 self.def_map.modules[module_id].scope.push_unnamed_trait(tr, vis);
1015 let glob_imports = self
1019 .flat_map(|v| v.iter())
1020 .filter(|(glob_importing_module, _)| {
1021 // we know all resolutions have the same visibility (`vis`), so we
1022 // just need to check that once
1023 vis.is_visible_from_def_map(self.db, &self.def_map, *glob_importing_module)
1026 .collect::<Vec<_>>();
1028 for (glob_importing_module, glob_import_vis) in glob_imports {
1029 self.update_recursive(
1030 glob_importing_module,
1039 fn resolve_macros(&mut self) -> ReachedFixedPoint {
1040 let mut macros = std::mem::take(&mut self.unresolved_macros);
1041 let mut resolved = Vec::new();
1042 let mut res = ReachedFixedPoint::Yes;
1043 macros.retain(|directive| {
1044 let resolver = |path| {
1045 let resolved_res = self.def_map.resolve_path_fp_with_macro(
1048 directive.module_id,
1050 BuiltinShadowMode::Module,
1052 resolved_res.resolved_def.take_macros()
1055 match &directive.kind {
1056 MacroDirectiveKind::FnLike { ast_id, expand_to } => {
1057 match macro_call_as_call_id(
1065 Ok(Ok(call_id)) => {
1066 resolved.push((directive.module_id, call_id, directive.depth));
1067 res = ReachedFixedPoint::No;
1070 Err(UnresolvedMacro { .. }) | Ok(Err(_)) => {}
1073 MacroDirectiveKind::Derive { ast_id, derive_attr } => {
1074 match derive_macro_as_call_id(
1082 self.def_map.modules[directive.module_id].scope.add_derive_macro_invoc(
1088 resolved.push((directive.module_id, call_id, directive.depth));
1089 res = ReachedFixedPoint::No;
1092 Err(UnresolvedMacro { .. }) => (),
1095 MacroDirectiveKind::Attr { ast_id, mod_item, attr } => {
1096 if let Some(ident) = ast_id.path.as_ident() {
1097 if let Some(helpers) = self.derive_helpers_in_scope.get(&ast_id.ast_id) {
1098 if helpers.contains(ident) {
1099 cov_mark::hit!(resolved_derive_helper);
1101 // Resolved to derive helper. Collect the item's attributes again,
1102 // starting after the derive helper.
1103 let file_id = ast_id.ast_id.file_id;
1104 let item_tree = self.db.file_item_tree(file_id);
1105 let mod_dir = self.mod_dirs[&directive.module_id].clone();
1106 self.skip_attrs.insert(InFile::new(file_id, *mod_item), attr.id);
1108 def_collector: &mut *self,
1109 macro_depth: directive.depth,
1110 module_id: directive.module_id,
1111 tree_id: TreeId::new(file_id, None),
1112 item_tree: &item_tree,
1115 .collect(&[*mod_item]);
1117 // Remove the original directive since we resolved it.
1118 res = ReachedFixedPoint::No;
1124 if !self.db.enable_proc_attr_macros() {
1128 // Not resolved to a derive helper, so try to resolve as a macro.
1129 match attr_macro_as_call_id(
1137 let loc: MacroCallLoc = self.db.lookup_intern_macro_call(call_id);
1139 // Skip #[test]/#[bench] expansion, which would merely result in more memory usage
1140 // due to duplicating functions into macro expansions
1141 if is_builtin_test_or_bench_attr(loc.def) {
1142 let file_id = ast_id.ast_id.file_id;
1143 let item_tree = self.db.file_item_tree(file_id);
1144 let mod_dir = self.mod_dirs[&directive.module_id].clone();
1145 self.skip_attrs.insert(InFile::new(file_id, *mod_item), attr.id);
1147 def_collector: &mut *self,
1148 macro_depth: directive.depth,
1149 module_id: directive.module_id,
1150 tree_id: TreeId::new(file_id, None),
1151 item_tree: &item_tree,
1154 .collect(&[*mod_item]);
1156 // Remove the original directive since we resolved it.
1157 res = ReachedFixedPoint::No;
1161 if let MacroDefKind::ProcMacro(exp, ..) = loc.def.kind {
1163 // Proc macros that cannot be expanded are treated as not
1164 // resolved, in order to fall back later.
1165 self.def_map.diagnostics.push(
1166 DefDiagnostic::unresolved_proc_macro(
1167 directive.module_id,
1172 let file_id = ast_id.ast_id.file_id;
1173 let item_tree = self.db.file_item_tree(file_id);
1174 let mod_dir = self.mod_dirs[&directive.module_id].clone();
1176 .insert(InFile::new(file_id, *mod_item), attr.id);
1178 def_collector: &mut *self,
1179 macro_depth: directive.depth,
1180 module_id: directive.module_id,
1181 tree_id: TreeId::new(file_id, None),
1182 item_tree: &item_tree,
1185 .collect(&[*mod_item]);
1187 // Remove the macro directive.
1192 self.def_map.modules[directive.module_id]
1194 .add_attr_macro_invoc(ast_id.ast_id, call_id);
1196 resolved.push((directive.module_id, call_id, directive.depth));
1197 res = ReachedFixedPoint::No;
1200 Err(UnresolvedMacro { .. }) => (),
1207 // Attribute resolution can add unresolved macro invocations, so concatenate the lists.
1208 self.unresolved_macros.extend(macros);
1210 for (module_id, macro_call_id, depth) in resolved {
1211 self.collect_macro_expansion(module_id, macro_call_id, depth);
1217 fn collect_macro_expansion(
1219 module_id: LocalModuleId,
1220 macro_call_id: MacroCallId,
1223 if EXPANSION_DEPTH_LIMIT.check(depth).is_err() {
1224 cov_mark::hit!(macro_expansion_overflow);
1225 tracing::warn!("macro expansion is too deep");
1228 let file_id = macro_call_id.as_file();
1230 // First, fetch the raw expansion result for purposes of error reporting. This goes through
1231 // `macro_expand_error` to avoid depending on the full expansion result (to improve
1233 let loc: MacroCallLoc = self.db.lookup_intern_macro_call(macro_call_id);
1234 let err = self.db.macro_expand_error(macro_call_id);
1235 if let Some(err) = err {
1236 let diag = match err {
1237 hir_expand::ExpandError::UnresolvedProcMacro => {
1238 // Missing proc macros are non-fatal, so they are handled specially.
1239 DefDiagnostic::unresolved_proc_macro(module_id, loc.kind.clone())
1241 _ => DefDiagnostic::macro_error(module_id, loc.kind.clone(), err.to_string()),
1244 self.def_map.diagnostics.push(diag);
1247 // If we've just resolved a derive, record its helper attributes.
1248 if let MacroCallKind::Derive { ast_id, .. } = &loc.kind {
1249 if loc.def.krate != self.def_map.krate {
1250 let def_map = self.db.crate_def_map(loc.def.krate);
1251 if let Some(def) = def_map.exported_proc_macros.get(&loc.def) {
1252 if let ProcMacroKind::CustomDerive { helpers } = &def.kind {
1253 self.derive_helpers_in_scope
1256 .extend(helpers.iter().cloned());
1262 // Then, fetch and process the item tree. This will reuse the expansion result from above.
1263 let item_tree = self.db.file_item_tree(file_id);
1264 let mod_dir = self.mod_dirs[&module_id].clone();
1266 def_collector: &mut *self,
1268 tree_id: TreeId::new(file_id, None),
1270 item_tree: &item_tree,
1273 .collect(item_tree.top_level_items());
1276 fn finish(mut self) -> DefMap {
1277 // Emit diagnostics for all remaining unexpanded macros.
1279 let _p = profile::span("DefCollector::finish");
1281 for directive in &self.unresolved_macros {
1282 match &directive.kind {
1283 MacroDirectiveKind::FnLike { ast_id, expand_to } => {
1284 match macro_call_as_call_id(
1290 let resolved_res = self.def_map.resolve_path_fp_with_macro(
1293 directive.module_id,
1295 BuiltinShadowMode::Module,
1297 resolved_res.resolved_def.take_macros()
1302 Err(UnresolvedMacro { path }) => {
1303 self.def_map.diagnostics.push(DefDiagnostic::unresolved_macro_call(
1304 directive.module_id,
1311 MacroDirectiveKind::Derive { .. } | MacroDirectiveKind::Attr { .. } => {
1312 // FIXME: we might want to diagnose this too
1317 // Emit diagnostics for all remaining unresolved imports.
1319 // We'd like to avoid emitting a diagnostics avalanche when some `extern crate` doesn't
1320 // resolve. We first emit diagnostics for unresolved extern crates and collect the missing
1321 // crate names. Then we emit diagnostics for unresolved imports, but only if the import
1322 // doesn't start with an unresolved crate's name. Due to renaming and reexports, this is a
1323 // heuristic, but it works in practice.
1324 let mut diagnosed_extern_crates = FxHashSet::default();
1325 for directive in &self.unresolved_imports {
1326 if let ImportSource::ExternCrate(krate) = directive.import.source {
1327 let item_tree = krate.item_tree(self.db);
1328 let extern_crate = &item_tree[krate.value];
1330 diagnosed_extern_crates.insert(extern_crate.name.clone());
1332 self.def_map.diagnostics.push(DefDiagnostic::unresolved_extern_crate(
1333 directive.module_id,
1334 InFile::new(krate.file_id(), extern_crate.ast_id),
1339 for directive in &self.unresolved_imports {
1340 if let ImportSource::Import { id: import, use_tree } = &directive.import.source {
1341 if let (Some(krate), PathKind::Plain | PathKind::Abs) =
1342 (directive.import.path.segments().first(), &directive.import.path.kind)
1344 if diagnosed_extern_crates.contains(krate) {
1349 self.def_map.diagnostics.push(DefDiagnostic::unresolved_import(
1350 directive.module_id,
1361 /// Walks a single module, populating defs, imports and macros
1362 struct ModCollector<'a, 'b> {
1363 def_collector: &'a mut DefCollector<'b>,
1365 module_id: LocalModuleId,
1367 item_tree: &'a ItemTree,
1371 impl ModCollector<'_, '_> {
1372 fn collect(&mut self, items: &[ModItem]) {
1373 let krate = self.def_collector.def_map.krate;
1375 // Note: don't assert that inserted value is fresh: it's simply not true
1377 self.def_collector.mod_dirs.insert(self.module_id, self.mod_dir.clone());
1379 // Prelude module is always considered to be `#[macro_use]`.
1380 if let Some(prelude_module) = self.def_collector.def_map.prelude {
1381 if prelude_module.krate != krate {
1382 cov_mark::hit!(prelude_is_macro_use);
1383 self.def_collector.import_all_macros_exported(self.module_id, prelude_module.krate);
1387 // This should be processed eagerly instead of deferred to resolving.
1388 // `#[macro_use] extern crate` is hoisted to imports macros before collecting
1391 let attrs = self.item_tree.attrs(self.def_collector.db, krate, (*item).into());
1392 if attrs.cfg().map_or(true, |cfg| self.is_cfg_enabled(&cfg)) {
1393 if let ModItem::ExternCrate(id) = item {
1394 let import = self.item_tree[*id].clone();
1395 let attrs = self.item_tree.attrs(
1396 self.def_collector.db,
1398 ModItem::from(*id).into(),
1400 if attrs.by_key("macro_use").exists() {
1401 self.def_collector.import_macros_from_extern_crate(self.module_id, &import);
1407 for &item in items {
1408 let attrs = self.item_tree.attrs(self.def_collector.db, krate, item.into());
1409 if let Some(cfg) = attrs.cfg() {
1410 if !self.is_cfg_enabled(&cfg) {
1411 self.emit_unconfigured_diagnostic(item, &cfg);
1416 if let Err(()) = self.resolve_attributes(&attrs, item) {
1417 // Do not process the item. It has at least one non-builtin attribute, so the
1418 // fixed-point algorithm is required to resolve the rest of them.
1422 let module = self.def_collector.def_map.module_id(self.module_id);
1426 ModItem::Mod(m) => self.collect_module(&self.item_tree[m], &attrs),
1427 ModItem::Import(import_id) => {
1428 let module_id = self.module_id;
1429 let imports = Import::from_use(
1430 self.def_collector.db,
1433 ItemTreeId::new(self.tree_id, import_id),
1435 self.def_collector.unresolved_imports.extend(imports.into_iter().map(
1436 |import| ImportDirective {
1439 status: PartialResolvedImport::Unresolved,
1443 ModItem::ExternCrate(import_id) => {
1444 self.def_collector.unresolved_imports.push(ImportDirective {
1445 module_id: self.module_id,
1446 import: Import::from_extern_crate(
1447 self.def_collector.db,
1450 ItemTreeId::new(self.tree_id, import_id),
1452 status: PartialResolvedImport::Unresolved,
1455 ModItem::ExternBlock(block) => self.collect(&self.item_tree[block].children),
1456 ModItem::MacroCall(mac) => self.collect_macro_call(&self.item_tree[mac]),
1457 ModItem::MacroRules(id) => self.collect_macro_rules(id),
1458 ModItem::MacroDef(id) => self.collect_macro_def(id),
1459 ModItem::Impl(imp) => {
1460 let module = self.def_collector.def_map.module_id(self.module_id);
1462 ImplLoc { container: module, id: ItemTreeId::new(self.tree_id, imp) }
1463 .intern(self.def_collector.db);
1464 self.def_collector.def_map.modules[self.module_id].scope.define_impl(impl_id)
1466 ModItem::Function(id) => {
1467 let func = &self.item_tree[id];
1469 let ast_id = InFile::new(self.file_id(), func.ast_id);
1470 self.collect_proc_macro_def(&func.name, ast_id, &attrs);
1472 def = Some(DefData {
1474 container: module.into(),
1475 id: ItemTreeId::new(self.tree_id, id),
1477 .intern(self.def_collector.db)
1480 visibility: &self.item_tree[func.visibility],
1481 has_constructor: false,
1484 ModItem::Struct(id) => {
1485 let it = &self.item_tree[id];
1487 def = Some(DefData {
1488 id: StructLoc { container: module, id: ItemTreeId::new(self.tree_id, id) }
1489 .intern(self.def_collector.db)
1492 visibility: &self.item_tree[it.visibility],
1493 has_constructor: !matches!(it.fields, Fields::Record(_)),
1496 ModItem::Union(id) => {
1497 let it = &self.item_tree[id];
1499 def = Some(DefData {
1500 id: UnionLoc { container: module, id: ItemTreeId::new(self.tree_id, id) }
1501 .intern(self.def_collector.db)
1504 visibility: &self.item_tree[it.visibility],
1505 has_constructor: false,
1508 ModItem::Enum(id) => {
1509 let it = &self.item_tree[id];
1511 def = Some(DefData {
1512 id: EnumLoc { container: module, id: ItemTreeId::new(self.tree_id, id) }
1513 .intern(self.def_collector.db)
1516 visibility: &self.item_tree[it.visibility],
1517 has_constructor: false,
1520 ModItem::Const(id) => {
1521 let it = &self.item_tree[id];
1522 let const_id = ConstLoc {
1523 container: module.into(),
1524 id: ItemTreeId::new(self.tree_id, id),
1526 .intern(self.def_collector.db);
1530 def = Some(DefData {
1531 id: const_id.into(),
1533 visibility: &self.item_tree[it.visibility],
1534 has_constructor: false,
1538 // const _: T = ...;
1539 self.def_collector.def_map.modules[self.module_id]
1541 .define_unnamed_const(const_id);
1545 ModItem::Static(id) => {
1546 let it = &self.item_tree[id];
1548 def = Some(DefData {
1549 id: StaticLoc { container: module, id: ItemTreeId::new(self.tree_id, id) }
1550 .intern(self.def_collector.db)
1553 visibility: &self.item_tree[it.visibility],
1554 has_constructor: false,
1557 ModItem::Trait(id) => {
1558 let it = &self.item_tree[id];
1560 def = Some(DefData {
1561 id: TraitLoc { container: module, id: ItemTreeId::new(self.tree_id, id) }
1562 .intern(self.def_collector.db)
1565 visibility: &self.item_tree[it.visibility],
1566 has_constructor: false,
1569 ModItem::TypeAlias(id) => {
1570 let it = &self.item_tree[id];
1572 def = Some(DefData {
1574 container: module.into(),
1575 id: ItemTreeId::new(self.tree_id, id),
1577 .intern(self.def_collector.db)
1580 visibility: &self.item_tree[it.visibility],
1581 has_constructor: false,
1586 if let Some(DefData { id, name, visibility, has_constructor }) = def {
1587 self.def_collector.def_map.modules[self.module_id].scope.declare(id);
1591 .resolve_visibility(self.def_collector.db, self.module_id, visibility)
1592 .unwrap_or(Visibility::Public);
1593 self.def_collector.update(
1595 &[(Some(name.clone()), PerNs::from_def(id, vis, has_constructor))],
1603 fn collect_module(&mut self, module: &Mod, attrs: &Attrs) {
1604 let path_attr = attrs.by_key("path").string_value();
1605 let is_macro_use = attrs.by_key("macro_use").exists();
1606 match &module.kind {
1607 // inline module, just recurse
1608 ModKind::Inline { items } => {
1609 let module_id = self.push_child_module(
1610 module.name.clone(),
1611 AstId::new(self.file_id(), module.ast_id),
1613 &self.item_tree[module.visibility],
1616 if let Some(mod_dir) = self.mod_dir.descend_into_definition(&module.name, path_attr)
1619 def_collector: &mut *self.def_collector,
1620 macro_depth: self.macro_depth,
1622 tree_id: self.tree_id,
1623 item_tree: self.item_tree,
1628 self.import_all_legacy_macros(module_id);
1632 // out of line module, resolve, parse and recurse
1633 ModKind::Outline {} => {
1634 let ast_id = AstId::new(self.tree_id.file_id(), module.ast_id);
1635 let db = self.def_collector.db;
1636 match self.mod_dir.resolve_declaration(db, self.file_id(), &module.name, path_attr)
1638 Ok((file_id, is_mod_rs, mod_dir)) => {
1639 let item_tree = db.file_item_tree(file_id.into());
1640 let is_enabled = item_tree
1641 .top_level_attrs(db, self.def_collector.def_map.krate)
1643 .map_or(true, |cfg| {
1644 self.def_collector.cfg_options.check(&cfg) != Some(false)
1647 let module_id = self.push_child_module(
1648 module.name.clone(),
1650 Some((file_id, is_mod_rs)),
1651 &self.item_tree[module.visibility],
1654 def_collector: &mut *self.def_collector,
1655 macro_depth: self.macro_depth,
1657 tree_id: TreeId::new(file_id.into(), None),
1658 item_tree: &item_tree,
1661 .collect(item_tree.top_level_items());
1664 .top_level_attrs(db, self.def_collector.def_map.krate)
1665 .by_key("macro_use")
1668 self.import_all_legacy_macros(module_id);
1673 self.def_collector.def_map.diagnostics.push(
1674 DefDiagnostic::unresolved_module(self.module_id, ast_id, candidate),
1682 fn push_child_module(
1685 declaration: AstId<ast::Module>,
1686 definition: Option<(FileId, bool)>,
1687 visibility: &crate::visibility::RawVisibility,
1688 ) -> LocalModuleId {
1692 .resolve_visibility(self.def_collector.db, self.module_id, visibility)
1693 .unwrap_or(Visibility::Public);
1694 let modules = &mut self.def_collector.def_map.modules;
1695 let origin = match definition {
1696 None => ModuleOrigin::Inline { definition: declaration },
1697 Some((definition, is_mod_rs)) => {
1698 ModuleOrigin::File { declaration, definition, is_mod_rs }
1701 let res = modules.alloc(ModuleData::new(origin, vis));
1702 modules[res].parent = Some(self.module_id);
1703 for (name, mac) in modules[self.module_id].scope.collect_legacy_macros() {
1704 modules[res].scope.define_legacy_macro(name, mac)
1706 modules[self.module_id].children.insert(name.clone(), res);
1707 let module = self.def_collector.def_map.module_id(res);
1708 let def: ModuleDefId = module.into();
1709 self.def_collector.def_map.modules[self.module_id].scope.declare(def);
1710 self.def_collector.update(
1712 &[(Some(name), PerNs::from_def(def, vis, false))],
1719 /// Resolves attributes on an item.
1721 /// Returns `Err` when some attributes could not be resolved to builtins and have been
1722 /// registered as unresolved.
1724 /// If `ignore_up_to` is `Some`, attributes preceding and including that attribute will be
1725 /// assumed to be resolved already.
1726 fn resolve_attributes(&mut self, attrs: &Attrs, mod_item: ModItem) -> Result<(), ()> {
1727 let mut ignore_up_to =
1728 self.def_collector.skip_attrs.get(&InFile::new(self.file_id(), mod_item)).copied();
1732 // FIXME: this should not be required, all attributes on an item should have a
1734 // Still, this occurs because `#[cfg_attr]` can "expand" to multiple attributes:
1735 // #[cfg_attr(not(off), unresolved, unresolved)]
1737 // We should come up with a different way to ID attributes.
1740 .skip_while(|attr| match ignore_up_to {
1741 Some(id) if attr.id == id => {
1742 ignore_up_to = None;
1750 if attr.path.as_ident() == Some(&hir_expand::name![derive]) {
1751 self.collect_derive(attr, mod_item);
1752 } else if self.is_builtin_or_registered_attr(&attr.path) {
1755 tracing::debug!("non-builtin attribute {}", attr.path);
1757 let ast_id = AstIdWithPath::new(
1759 mod_item.ast_id(self.item_tree),
1760 attr.path.as_ref().clone(),
1762 self.def_collector.unresolved_macros.push(MacroDirective {
1763 module_id: self.module_id,
1764 depth: self.macro_depth + 1,
1765 kind: MacroDirectiveKind::Attr { ast_id, attr: attr.clone(), mod_item },
1775 fn is_builtin_or_registered_attr(&self, path: &ModPath) -> bool {
1776 if path.kind == PathKind::Plain {
1777 if let Some(tool_module) = path.segments().first() {
1778 let tool_module = tool_module.to_smol_str();
1779 let is_tool = builtin_attr::TOOL_MODULES
1782 .chain(self.def_collector.registered_tools.iter().map(SmolStr::as_str))
1783 .any(|m| tool_module == *m);
1789 if let Some(name) = path.as_ident() {
1790 let name = name.to_smol_str();
1791 let is_inert = builtin_attr::INERT_ATTRIBUTES
1794 .chain(self.def_collector.registered_attrs.iter().map(SmolStr::as_str))
1795 .any(|attr| name == *attr);
1803 fn collect_derive(&mut self, attr: &Attr, mod_item: ModItem) {
1804 let ast_id: FileAstId<ast::Item> = match mod_item {
1805 ModItem::Struct(it) => self.item_tree[it].ast_id.upcast(),
1806 ModItem::Union(it) => self.item_tree[it].ast_id.upcast(),
1807 ModItem::Enum(it) => self.item_tree[it].ast_id.upcast(),
1809 // Cannot use derive on this item.
1815 match attr.parse_derive() {
1816 Some(derive_macros) => {
1817 for path in derive_macros {
1818 let ast_id = AstIdWithPath::new(self.file_id(), ast_id, path);
1819 self.def_collector.unresolved_macros.push(MacroDirective {
1820 module_id: self.module_id,
1821 depth: self.macro_depth + 1,
1822 kind: MacroDirectiveKind::Derive { ast_id, derive_attr: attr.id },
1828 tracing::debug!("malformed derive: {:?}", attr);
1833 /// If `attrs` registers a procedural macro, collects its definition.
1834 fn collect_proc_macro_def(&mut self, func_name: &Name, ast_id: AstId<ast::Fn>, attrs: &Attrs) {
1835 // FIXME: this should only be done in the root module of `proc-macro` crates, not everywhere
1836 if let Some(proc_macro) = attrs.parse_proc_macro_decl(func_name) {
1837 self.def_collector.export_proc_macro(proc_macro, ast_id);
1841 fn collect_macro_rules(&mut self, id: FileItemTreeId<MacroRules>) {
1842 let krate = self.def_collector.def_map.krate;
1843 let mac = &self.item_tree[id];
1844 let attrs = self.item_tree.attrs(self.def_collector.db, krate, ModItem::from(id).into());
1845 let ast_id = InFile::new(self.file_id(), mac.ast_id.upcast());
1847 let export_attr = attrs.by_key("macro_export");
1849 let is_export = export_attr.exists();
1850 let is_local_inner = if is_export {
1851 export_attr.tt_values().map(|it| &it.token_trees).flatten().any(|it| match it {
1852 tt::TokenTree::Leaf(tt::Leaf::Ident(ident)) => {
1853 ident.text.contains("local_inner_macros")
1861 // Case 1: builtin macros
1862 if attrs.by_key("rustc_builtin_macro").exists() {
1863 // `#[rustc_builtin_macro = "builtin_name"]` overrides the `macro_rules!` name.
1865 let name = match attrs.by_key("rustc_builtin_macro").string_value() {
1867 // FIXME: a hacky way to create a Name from string.
1868 name = tt::Ident { text: it.clone(), id: tt::TokenId::unspecified() }.as_name();
1872 match attrs.by_key("rustc_builtin_macro").tt_values().next().and_then(|tt| {
1873 match tt.token_trees.first() {
1874 Some(tt::TokenTree::Leaf(tt::Leaf::Ident(name))) => Some(name),
1879 name = ident.as_name();
1886 let krate = self.def_collector.def_map.krate;
1887 match find_builtin_macro(name, krate, ast_id) {
1889 self.def_collector.define_macro_rules(
1901 .push(DefDiagnostic::unimplemented_builtin_macro(self.module_id, ast_id));
1906 // Case 2: normal `macro_rules!` macro
1907 let macro_id = MacroDefId {
1908 krate: self.def_collector.def_map.krate,
1909 kind: MacroDefKind::Declarative(ast_id),
1910 local_inner: is_local_inner,
1912 self.def_collector.define_macro_rules(
1920 fn collect_macro_def(&mut self, id: FileItemTreeId<MacroDef>) {
1921 let krate = self.def_collector.def_map.krate;
1922 let mac = &self.item_tree[id];
1923 let ast_id = InFile::new(self.file_id(), mac.ast_id.upcast());
1925 // Case 1: builtin macros
1926 let attrs = self.item_tree.attrs(self.def_collector.db, krate, ModItem::from(id).into());
1927 if attrs.by_key("rustc_builtin_macro").exists() {
1928 let macro_id = find_builtin_macro(&mac.name, krate, ast_id)
1929 .or_else(|| find_builtin_derive(&mac.name, krate, ast_id))
1930 .or_else(|| find_builtin_attr(&mac.name, krate, ast_id));
1934 self.def_collector.define_macro_def(
1938 &self.item_tree[mac.visibility],
1946 .push(DefDiagnostic::unimplemented_builtin_macro(self.module_id, ast_id));
1951 // Case 2: normal `macro`
1952 let macro_id = MacroDefId {
1953 krate: self.def_collector.def_map.krate,
1954 kind: MacroDefKind::Declarative(ast_id),
1958 self.def_collector.define_macro_def(
1962 &self.item_tree[mac.visibility],
1966 fn collect_macro_call(&mut self, mac: &MacroCall) {
1967 let ast_id = AstIdWithPath::new(self.file_id(), mac.ast_id, (*mac.path).clone());
1969 // Case 1: try to resolve in legacy scope and expand macro_rules
1970 let mut error = None;
1971 match macro_call_as_call_id(
1974 self.def_collector.db,
1975 self.def_collector.def_map.krate,
1977 path.as_ident().and_then(|name| {
1978 self.def_collector.def_map.with_ancestor_maps(
1979 self.def_collector.db,
1981 &mut |map, module| map[module].scope.get_legacy_macro(name),
1986 error.get_or_insert(err);
1989 Ok(Ok(macro_call_id)) => {
1990 // Legacy macros need to be expanded immediately, so that any macros they produce
1992 self.def_collector.collect_macro_expansion(
1995 self.macro_depth + 1,
1998 if let Some(err) = error {
1999 self.def_collector.def_map.diagnostics.push(DefDiagnostic::macro_error(
2001 MacroCallKind::FnLike { ast_id: ast_id.ast_id, expand_to: mac.expand_to },
2009 // Built-in macro failed eager expansion.
2011 self.def_collector.def_map.diagnostics.push(DefDiagnostic::macro_error(
2013 MacroCallKind::FnLike { ast_id: ast_id.ast_id, expand_to: mac.expand_to },
2014 error.unwrap().to_string(),
2018 Err(UnresolvedMacro { .. }) => (),
2021 // Case 2: resolve in module scope, expand during name resolution.
2022 self.def_collector.unresolved_macros.push(MacroDirective {
2023 module_id: self.module_id,
2024 depth: self.macro_depth + 1,
2025 kind: MacroDirectiveKind::FnLike { ast_id, expand_to: mac.expand_to },
2029 fn import_all_legacy_macros(&mut self, module_id: LocalModuleId) {
2030 let macros = self.def_collector.def_map[module_id].scope.collect_legacy_macros();
2031 for (name, macro_) in macros {
2032 self.def_collector.define_legacy_macro(self.module_id, name.clone(), macro_);
2036 fn is_cfg_enabled(&self, cfg: &CfgExpr) -> bool {
2037 self.def_collector.cfg_options.check(cfg) != Some(false)
2040 fn emit_unconfigured_diagnostic(&mut self, item: ModItem, cfg: &CfgExpr) {
2041 let ast_id = item.ast_id(self.item_tree);
2043 let ast_id = InFile::new(self.file_id(), ast_id);
2044 self.def_collector.def_map.diagnostics.push(DefDiagnostic::unconfigured_code(
2048 self.def_collector.cfg_options.clone(),
2052 fn file_id(&self) -> HirFileId {
2053 self.tree_id.file_id()
2059 use crate::{db::DefDatabase, test_db::TestDB};
2060 use base_db::{fixture::WithFixture, SourceDatabase};
2064 fn do_collect_defs(db: &dyn DefDatabase, def_map: DefMap) -> DefMap {
2065 let mut collector = DefCollector {
2068 deps: FxHashMap::default(),
2069 glob_imports: FxHashMap::default(),
2070 unresolved_imports: Vec::new(),
2071 resolved_imports: Vec::new(),
2072 unresolved_macros: Vec::new(),
2073 mod_dirs: FxHashMap::default(),
2074 cfg_options: &CfgOptions::default(),
2075 proc_macros: Default::default(),
2076 exports_proc_macros: false,
2077 from_glob_import: Default::default(),
2078 skip_attrs: Default::default(),
2079 derive_helpers_in_scope: Default::default(),
2080 registered_attrs: Default::default(),
2081 registered_tools: Default::default(),
2083 collector.seed_with_top_level();
2084 collector.collect();
2088 fn do_resolve(not_ra_fixture: &str) -> DefMap {
2089 let (db, file_id) = TestDB::with_single_file(not_ra_fixture);
2090 let krate = db.test_crate();
2092 let edition = db.crate_graph()[krate].edition;
2093 let module_origin = ModuleOrigin::CrateRoot { definition: file_id };
2094 let def_map = DefMap::empty(krate, edition, module_origin);
2095 do_collect_defs(&db, def_map)
2099 fn test_macro_expand_will_stop_1() {
2103 ($($ty:ty)*) => { foo!($($ty)*); }
2111 ($($ty:ty)*) => { foo!(() $($ty)*); }
2120 fn test_macro_expand_will_stop_2() {
2121 // FIXME: this test does succeed, but takes quite a while: 90 seconds in
2122 // the release mode. That's why the argument is not an ra_fixture --
2123 // otherwise injection highlighting gets stuck.
2125 // We need to find a way to fail this faster.
2129 ($($ty:ty)*) => { foo!($($ty)* $($ty)*); }