5 use std::{cell::RefCell, fmt, iter};
7 use base_db::{FileId, FileRange};
9 body, macro_id_to_def_id,
10 resolver::{self, HasResolver, Resolver, TypeNs},
12 AsMacroCall, FunctionId, MacroId, TraitId, VariantId,
16 name::{known, AsName},
17 ExpansionInfo, MacroCallId,
20 use itertools::Itertools;
21 use rustc_hash::{FxHashMap, FxHashSet};
22 use smallvec::{smallvec, SmallVec};
24 algo::skip_trivia_token,
25 ast::{self, HasAttrs as _, HasGenericParams, HasLoopBody},
26 match_ast, AstNode, Direction, SyntaxNode, SyntaxNodePtr, SyntaxToken, TextSize,
31 semantics::source_to_def::{ChildContainer, SourceToDefCache, SourceToDefCtx},
32 source_analyzer::{resolve_hir_path, SourceAnalyzer},
33 Access, BindingMode, BuiltinAttr, Callable, ConstParam, Crate, Field, Function, HasSource,
34 HirFileId, Impl, InFile, Label, LifetimeParam, Local, Macro, Module, ModuleDef, Name, Path,
35 ScopeDef, ToolModule, Trait, Type, TypeAlias, TypeParam, VariantDef,
38 #[derive(Debug, Clone, PartialEq, Eq)]
39 pub enum PathResolution {
42 /// A local binding (only value namespace)
47 ConstParam(ConstParam),
49 BuiltinAttr(BuiltinAttr),
50 ToolModule(ToolModule),
54 pub(crate) fn in_type_ns(&self) -> Option<TypeNs> {
56 PathResolution::Def(ModuleDef::Adt(adt)) => Some(TypeNs::AdtId((*adt).into())),
57 PathResolution::Def(ModuleDef::BuiltinType(builtin)) => {
58 Some(TypeNs::BuiltinType((*builtin).into()))
62 | ModuleDef::Variant(_)
64 | ModuleDef::Function(_)
65 | ModuleDef::Module(_)
66 | ModuleDef::Static(_)
67 | ModuleDef::Trait(_),
69 PathResolution::Def(ModuleDef::TypeAlias(alias)) => {
70 Some(TypeNs::TypeAliasId((*alias).into()))
72 PathResolution::BuiltinAttr(_)
73 | PathResolution::ToolModule(_)
74 | PathResolution::Local(_)
75 | PathResolution::ConstParam(_) => None,
76 PathResolution::TypeParam(param) => Some(TypeNs::GenericParam((*param).into())),
77 PathResolution::SelfType(impl_def) => Some(TypeNs::SelfType((*impl_def).into())),
84 /// The original type of the expression or pattern.
86 /// The adjusted type, if an adjustment happened.
87 pub adjusted: Option<Type>,
91 pub fn original(self) -> Type {
95 pub fn has_adjustment(&self) -> bool {
96 self.adjusted.is_some()
99 /// The adjusted type, or the original in case no adjustments occurred.
100 pub fn adjusted(self) -> Type {
101 self.adjusted.unwrap_or(self.original)
105 /// Primary API to get semantic information, like types, from syntax trees.
106 pub struct Semantics<'db, DB> {
108 imp: SemanticsImpl<'db>,
111 pub struct SemanticsImpl<'db> {
112 pub db: &'db dyn HirDatabase,
113 s2d_cache: RefCell<SourceToDefCache>,
114 expansion_info_cache: RefCell<FxHashMap<HirFileId, Option<ExpansionInfo>>>,
115 // Rootnode to HirFileId cache
116 cache: RefCell<FxHashMap<SyntaxNode, HirFileId>>,
117 // MacroCall to its expansion's HirFileId cache
118 macro_call_cache: RefCell<FxHashMap<InFile<ast::MacroCall>, HirFileId>>,
121 impl<DB> fmt::Debug for Semantics<'_, DB> {
122 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
123 write!(f, "Semantics {{ ... }}")
127 impl<'db, DB: HirDatabase> Semantics<'db, DB> {
128 pub fn new(db: &DB) -> Semantics<DB> {
129 let impl_ = SemanticsImpl::new(db);
130 Semantics { db, imp: impl_ }
133 pub fn parse(&self, file_id: FileId) -> ast::SourceFile {
134 self.imp.parse(file_id)
137 pub fn parse_or_expand(&self, file_id: HirFileId) -> Option<SyntaxNode> {
138 self.imp.parse_or_expand(file_id)
141 pub fn expand(&self, macro_call: &ast::MacroCall) -> Option<SyntaxNode> {
142 self.imp.expand(macro_call)
145 /// If `item` has an attribute macro attached to it, expands it.
146 pub fn expand_attr_macro(&self, item: &ast::Item) -> Option<SyntaxNode> {
147 self.imp.expand_attr_macro(item)
150 pub fn expand_derive_as_pseudo_attr_macro(&self, attr: &ast::Attr) -> Option<SyntaxNode> {
151 self.imp.expand_derive_as_pseudo_attr_macro(attr)
154 pub fn resolve_derive_macro(&self, derive: &ast::Attr) -> Option<Vec<Option<Macro>>> {
155 self.imp.resolve_derive_macro(derive)
158 pub fn expand_derive_macro(&self, derive: &ast::Attr) -> Option<Vec<SyntaxNode>> {
159 self.imp.expand_derive_macro(derive)
162 pub fn is_attr_macro_call(&self, item: &ast::Item) -> bool {
163 self.imp.is_attr_macro_call(item)
166 pub fn is_derive_annotated(&self, item: &ast::Adt) -> bool {
167 self.imp.is_derive_annotated(item)
170 pub fn speculative_expand(
172 actual_macro_call: &ast::MacroCall,
173 speculative_args: &ast::TokenTree,
174 token_to_map: SyntaxToken,
175 ) -> Option<(SyntaxNode, SyntaxToken)> {
176 self.imp.speculative_expand(actual_macro_call, speculative_args, token_to_map)
179 pub fn speculative_expand_attr_macro(
181 actual_macro_call: &ast::Item,
182 speculative_args: &ast::Item,
183 token_to_map: SyntaxToken,
184 ) -> Option<(SyntaxNode, SyntaxToken)> {
185 self.imp.speculative_expand_attr(actual_macro_call, speculative_args, token_to_map)
188 pub fn speculative_expand_derive_as_pseudo_attr_macro(
190 actual_macro_call: &ast::Attr,
191 speculative_args: &ast::Attr,
192 token_to_map: SyntaxToken,
193 ) -> Option<(SyntaxNode, SyntaxToken)> {
194 self.imp.speculative_expand_derive_as_pseudo_attr_macro(
201 /// Descend the token into macrocalls to its first mapped counterpart.
202 pub fn descend_into_macros_single(&self, token: SyntaxToken) -> SyntaxToken {
203 self.imp.descend_into_macros_single(token)
206 /// Descend the token into macrocalls to all its mapped counterparts.
207 pub fn descend_into_macros(&self, token: SyntaxToken) -> SmallVec<[SyntaxToken; 1]> {
208 self.imp.descend_into_macros(token)
211 /// Descend the token into macrocalls to all its mapped counterparts that have the same text as the input token.
213 /// Returns the original non descended token if none of the mapped counterparts have the same text.
214 pub fn descend_into_macros_with_same_text(
217 ) -> SmallVec<[SyntaxToken; 1]> {
218 self.imp.descend_into_macros_with_same_text(token)
221 /// Maps a node down by mapping its first and last token down.
222 pub fn descend_node_into_attributes<N: AstNode>(&self, node: N) -> SmallVec<[N; 1]> {
223 self.imp.descend_node_into_attributes(node)
226 /// Search for a definition's source and cache its syntax tree
227 pub fn source<Def: HasSource>(&self, def: Def) -> Option<InFile<Def::Ast>>
234 pub fn hir_file_for(&self, syntax_node: &SyntaxNode) -> HirFileId {
235 self.imp.find_file(syntax_node).file_id
238 /// Attempts to map the node out of macro expanded files returning the original file range.
239 /// If upmapping is not possible, this will fall back to the range of the macro call of the
240 /// macro file the node resides in.
241 pub fn original_range(&self, node: &SyntaxNode) -> FileRange {
242 self.imp.original_range(node)
245 /// Attempts to map the node out of macro expanded files returning the original file range.
246 pub fn original_range_opt(&self, node: &SyntaxNode) -> Option<FileRange> {
247 self.imp.original_range_opt(node)
250 /// Attempts to map the node out of macro expanded files.
251 /// This only work for attribute expansions, as other ones do not have nodes as input.
252 pub fn original_ast_node<N: AstNode>(&self, node: N) -> Option<N> {
253 self.imp.original_ast_node(node)
256 pub fn diagnostics_display_range(&self, diagnostics: InFile<SyntaxNodePtr>) -> FileRange {
257 self.imp.diagnostics_display_range(diagnostics)
260 pub fn token_ancestors_with_macros(
263 ) -> impl Iterator<Item = SyntaxNode> + '_ {
264 token.parent().into_iter().flat_map(move |it| self.ancestors_with_macros(it))
267 /// Iterates the ancestors of the given node, climbing up macro expansions while doing so.
268 pub fn ancestors_with_macros(&self, node: SyntaxNode) -> impl Iterator<Item = SyntaxNode> + '_ {
269 self.imp.ancestors_with_macros(node)
272 pub fn ancestors_at_offset_with_macros(
276 ) -> impl Iterator<Item = SyntaxNode> + '_ {
277 self.imp.ancestors_at_offset_with_macros(node, offset)
280 /// Find an AstNode by offset inside SyntaxNode, if it is inside *Macrofile*,
281 /// search up until it is of the target AstNode type
282 pub fn find_node_at_offset_with_macros<N: AstNode>(
287 self.imp.ancestors_at_offset_with_macros(node, offset).find_map(N::cast)
290 /// Find an AstNode by offset inside SyntaxNode, if it is inside *MacroCall*,
291 /// descend it and find again
292 pub fn find_node_at_offset_with_descend<N: AstNode>(
297 self.imp.descend_node_at_offset(node, offset).flatten().find_map(N::cast)
300 /// Find an AstNode by offset inside SyntaxNode, if it is inside *MacroCall*,
301 /// descend it and find again
302 pub fn find_nodes_at_offset_with_descend<'slf, N: AstNode + 'slf>(
306 ) -> impl Iterator<Item = N> + 'slf {
307 self.imp.descend_node_at_offset(node, offset).filter_map(|mut it| it.find_map(N::cast))
310 pub fn resolve_lifetime_param(&self, lifetime: &ast::Lifetime) -> Option<LifetimeParam> {
311 self.imp.resolve_lifetime_param(lifetime)
314 pub fn resolve_label(&self, lifetime: &ast::Lifetime) -> Option<Label> {
315 self.imp.resolve_label(lifetime)
318 pub fn resolve_type(&self, ty: &ast::Type) -> Option<Type> {
319 self.imp.resolve_type(ty)
322 // FIXME: Figure out a nice interface to inspect adjustments
323 pub fn is_implicit_reborrow(&self, expr: &ast::Expr) -> Option<Mutability> {
324 self.imp.is_implicit_reborrow(expr)
327 pub fn type_of_expr(&self, expr: &ast::Expr) -> Option<TypeInfo> {
328 self.imp.type_of_expr(expr)
331 pub fn type_of_pat(&self, pat: &ast::Pat) -> Option<TypeInfo> {
332 self.imp.type_of_pat(pat)
335 pub fn type_of_self(&self, param: &ast::SelfParam) -> Option<Type> {
336 self.imp.type_of_self(param)
339 pub fn pattern_adjustments(&self, pat: &ast::Pat) -> SmallVec<[Type; 1]> {
340 self.imp.pattern_adjustments(pat)
343 pub fn binding_mode_of_pat(&self, pat: &ast::IdentPat) -> Option<BindingMode> {
344 self.imp.binding_mode_of_pat(pat)
347 pub fn resolve_method_call(&self, call: &ast::MethodCallExpr) -> Option<Function> {
348 self.imp.resolve_method_call(call).map(Function::from)
351 pub fn resolve_method_call_as_callable(&self, call: &ast::MethodCallExpr) -> Option<Callable> {
352 self.imp.resolve_method_call_as_callable(call)
355 pub fn resolve_field(&self, field: &ast::FieldExpr) -> Option<Field> {
356 self.imp.resolve_field(field)
359 pub fn resolve_record_field(
361 field: &ast::RecordExprField,
362 ) -> Option<(Field, Option<Local>, Type)> {
363 self.imp.resolve_record_field(field)
366 pub fn resolve_record_pat_field(&self, field: &ast::RecordPatField) -> Option<Field> {
367 self.imp.resolve_record_pat_field(field)
370 pub fn resolve_macro_call(&self, macro_call: &ast::MacroCall) -> Option<Macro> {
371 self.imp.resolve_macro_call(macro_call)
374 pub fn is_unsafe_macro_call(&self, macro_call: &ast::MacroCall) -> bool {
375 self.imp.is_unsafe_macro_call(macro_call)
378 pub fn resolve_attr_macro_call(&self, item: &ast::Item) -> Option<Macro> {
379 self.imp.resolve_attr_macro_call(item)
382 pub fn resolve_path(&self, path: &ast::Path) -> Option<PathResolution> {
383 self.imp.resolve_path(path)
386 pub fn resolve_extern_crate(&self, extern_crate: &ast::ExternCrate) -> Option<Crate> {
387 self.imp.resolve_extern_crate(extern_crate)
390 pub fn resolve_variant(&self, record_lit: ast::RecordExpr) -> Option<VariantDef> {
391 self.imp.resolve_variant(record_lit).map(VariantDef::from)
394 pub fn resolve_bind_pat_to_const(&self, pat: &ast::IdentPat) -> Option<ModuleDef> {
395 self.imp.resolve_bind_pat_to_const(pat)
398 pub fn record_literal_missing_fields(&self, literal: &ast::RecordExpr) -> Vec<(Field, Type)> {
399 self.imp.record_literal_missing_fields(literal)
402 pub fn record_pattern_missing_fields(&self, pattern: &ast::RecordPat) -> Vec<(Field, Type)> {
403 self.imp.record_pattern_missing_fields(pattern)
406 pub fn to_def<T: ToDef>(&self, src: &T) -> Option<T::Def> {
407 let src = self.imp.find_file(src.syntax()).with_value(src).cloned();
408 T::to_def(&self.imp, src)
411 pub fn to_module_def(&self, file: FileId) -> Option<Module> {
412 self.imp.to_module_def(file).next()
415 pub fn to_module_defs(&self, file: FileId) -> impl Iterator<Item = Module> {
416 self.imp.to_module_def(file)
419 pub fn scope(&self, node: &SyntaxNode) -> Option<SemanticsScope<'db>> {
423 pub fn scope_at_offset(
427 ) -> Option<SemanticsScope<'db>> {
428 self.imp.scope_at_offset(node, offset)
431 pub fn scope_for_def(&self, def: Trait) -> SemanticsScope<'db> {
432 self.imp.scope_for_def(def)
435 pub fn assert_contains_node(&self, node: &SyntaxNode) {
436 self.imp.assert_contains_node(node)
439 pub fn is_unsafe_method_call(&self, method_call_expr: &ast::MethodCallExpr) -> bool {
440 self.imp.is_unsafe_method_call(method_call_expr)
443 pub fn is_unsafe_ref_expr(&self, ref_expr: &ast::RefExpr) -> bool {
444 self.imp.is_unsafe_ref_expr(ref_expr)
447 pub fn is_unsafe_ident_pat(&self, ident_pat: &ast::IdentPat) -> bool {
448 self.imp.is_unsafe_ident_pat(ident_pat)
452 impl<'db> SemanticsImpl<'db> {
453 fn new(db: &'db dyn HirDatabase) -> Self {
456 s2d_cache: Default::default(),
457 cache: Default::default(),
458 expansion_info_cache: Default::default(),
459 macro_call_cache: Default::default(),
463 fn parse(&self, file_id: FileId) -> ast::SourceFile {
464 let tree = self.db.parse(file_id).tree();
465 self.cache(tree.syntax().clone(), file_id.into());
469 fn parse_or_expand(&self, file_id: HirFileId) -> Option<SyntaxNode> {
470 let node = self.db.parse_or_expand(file_id)?;
471 self.cache(node.clone(), file_id);
475 fn expand(&self, macro_call: &ast::MacroCall) -> Option<SyntaxNode> {
476 let sa = self.analyze_no_infer(macro_call.syntax())?;
477 let file_id = sa.expand(self.db, InFile::new(sa.file_id, macro_call))?;
478 let node = self.parse_or_expand(file_id)?;
482 fn expand_attr_macro(&self, item: &ast::Item) -> Option<SyntaxNode> {
483 let src = self.wrap_node_infile(item.clone());
484 let macro_call_id = self.with_ctx(|ctx| ctx.item_to_macro_call(src))?;
485 self.parse_or_expand(macro_call_id.as_file())
488 fn expand_derive_as_pseudo_attr_macro(&self, attr: &ast::Attr) -> Option<SyntaxNode> {
489 let src = self.wrap_node_infile(attr.clone());
490 let adt = attr.syntax().parent().and_then(ast::Adt::cast)?;
491 let call_id = self.with_ctx(|ctx| {
492 ctx.attr_to_derive_macro_call(src.with_value(&adt), src).map(|(_, it, _)| it)
494 self.parse_or_expand(call_id.as_file())
497 fn resolve_derive_macro(&self, attr: &ast::Attr) -> Option<Vec<Option<Macro>>> {
498 let calls = self.derive_macro_calls(attr)?;
499 self.with_ctx(|ctx| {
504 macro_call_to_macro_id(ctx, self.db.upcast(), call?).map(|id| Macro { id })
511 fn expand_derive_macro(&self, attr: &ast::Attr) -> Option<Vec<SyntaxNode>> {
512 let res: Vec<_> = self
513 .derive_macro_calls(attr)?
516 let file_id = call?.as_file();
517 let node = self.db.parse_or_expand(file_id)?;
518 self.cache(node.clone(), file_id);
525 fn derive_macro_calls(&self, attr: &ast::Attr) -> Option<Vec<Option<MacroCallId>>> {
526 let adt = attr.syntax().parent().and_then(ast::Adt::cast)?;
527 let file_id = self.find_file(adt.syntax()).file_id;
528 let adt = InFile::new(file_id, &adt);
529 let src = InFile::new(file_id, attr.clone());
530 self.with_ctx(|ctx| {
531 let (.., res) = ctx.attr_to_derive_macro_call(adt, src)?;
536 fn is_derive_annotated(&self, adt: &ast::Adt) -> bool {
537 let file_id = self.find_file(adt.syntax()).file_id;
538 let adt = InFile::new(file_id, adt);
539 self.with_ctx(|ctx| ctx.has_derives(adt))
542 fn is_attr_macro_call(&self, item: &ast::Item) -> bool {
543 let file_id = self.find_file(item.syntax()).file_id;
544 let src = InFile::new(file_id, item.clone());
545 self.with_ctx(|ctx| ctx.item_to_macro_call(src).is_some())
548 fn speculative_expand(
550 actual_macro_call: &ast::MacroCall,
551 speculative_args: &ast::TokenTree,
552 token_to_map: SyntaxToken,
553 ) -> Option<(SyntaxNode, SyntaxToken)> {
554 let SourceAnalyzer { file_id, resolver, .. } =
555 self.analyze_no_infer(actual_macro_call.syntax())?;
556 let macro_call = InFile::new(file_id, actual_macro_call);
557 let krate = resolver.krate();
558 let macro_call_id = macro_call.as_call_id(self.db.upcast(), krate, |path| {
560 .resolve_path_as_macro(self.db.upcast(), &path)
561 .map(|it| macro_id_to_def_id(self.db.upcast(), it))
563 hir_expand::db::expand_speculative(
566 speculative_args.syntax(),
571 fn speculative_expand_attr(
573 actual_macro_call: &ast::Item,
574 speculative_args: &ast::Item,
575 token_to_map: SyntaxToken,
576 ) -> Option<(SyntaxNode, SyntaxToken)> {
577 let macro_call = self.wrap_node_infile(actual_macro_call.clone());
578 let macro_call_id = self.with_ctx(|ctx| ctx.item_to_macro_call(macro_call))?;
579 hir_expand::db::expand_speculative(
582 speculative_args.syntax(),
587 fn speculative_expand_derive_as_pseudo_attr_macro(
589 actual_macro_call: &ast::Attr,
590 speculative_args: &ast::Attr,
591 token_to_map: SyntaxToken,
592 ) -> Option<(SyntaxNode, SyntaxToken)> {
593 let attr = self.wrap_node_infile(actual_macro_call.clone());
594 let adt = actual_macro_call.syntax().parent().and_then(ast::Adt::cast)?;
595 let macro_call_id = self.with_ctx(|ctx| {
596 ctx.attr_to_derive_macro_call(attr.with_value(&adt), attr).map(|(_, it, _)| it)
598 hir_expand::db::expand_speculative(
601 speculative_args.syntax(),
606 // This might not be the correct way to do this, but it works for now
607 fn descend_node_into_attributes<N: AstNode>(&self, node: N) -> SmallVec<[N; 1]> {
608 let mut res = smallvec![];
610 let first = skip_trivia_token(node.syntax().first_token()?, Direction::Next)?;
611 let last = skip_trivia_token(node.syntax().last_token()?, Direction::Prev)?;
614 let (first, last) = match tokens {
620 self.descend_into_macros_impl(first, &mut |InFile { value, .. }| {
621 if let Some(node) = value.ancestors().find_map(N::cast) {
627 // Descend first and last token, then zip them to look for the node they belong to
628 let mut scratch: SmallVec<[_; 1]> = smallvec![];
629 self.descend_into_macros_impl(first, &mut |token| {
634 let mut scratch = scratch.into_iter();
635 self.descend_into_macros_impl(
637 &mut |InFile { value: last, file_id: last_fid }| {
638 if let Some(InFile { value: first, file_id: first_fid }) = scratch.next() {
639 if first_fid == last_fid {
640 if let Some(p) = first.parent() {
641 let range = first.text_range().cover(last.text_range());
642 let node = find_root(&p)
643 .covering_element(range)
645 .take_while(|it| it.text_range() == range)
647 if let Some(node) = node {
660 fn descend_into_macros(&self, token: SyntaxToken) -> SmallVec<[SyntaxToken; 1]> {
661 let mut res = smallvec![];
662 self.descend_into_macros_impl(token, &mut |InFile { value, .. }| {
669 fn descend_into_macros_with_same_text(&self, token: SyntaxToken) -> SmallVec<[SyntaxToken; 1]> {
670 let text = token.text();
671 let mut res = smallvec![];
672 self.descend_into_macros_impl(token.clone(), &mut |InFile { value, .. }| {
673 if value.text() == text {
684 fn descend_into_macros_single(&self, token: SyntaxToken) -> SyntaxToken {
685 let mut res = token.clone();
686 self.descend_into_macros_impl(token, &mut |InFile { value, .. }| {
693 fn descend_into_macros_impl(
696 f: &mut dyn FnMut(InFile<SyntaxToken>) -> bool,
698 let _p = profile::span("descend_into_macros");
699 let parent = match token.parent() {
703 let sa = match self.analyze_no_infer(&parent) {
707 let mut stack: SmallVec<[_; 4]> = smallvec![InFile::new(sa.file_id, token)];
708 let mut cache = self.expansion_info_cache.borrow_mut();
709 let mut mcache = self.macro_call_cache.borrow_mut();
711 let mut process_expansion_for_token =
712 |stack: &mut SmallVec<_>, macro_file, item, token: InFile<&_>| {
713 let expansion_info = cache
715 .or_insert_with(|| macro_file.expansion_info(self.db.upcast()))
719 let InFile { file_id, value } = expansion_info.expanded();
720 self.cache(value, file_id);
723 let mapped_tokens = expansion_info.map_token_down(self.db.upcast(), item, token)?;
724 let len = stack.len();
726 // requeue the tokens we got from mapping our current token down
727 stack.extend(mapped_tokens);
728 // if the length changed we have found a mapping for the token
729 (stack.len() != len).then(|| ())
732 // Remap the next token in the queue into a macro call its in, if it is not being remapped
733 // either due to not being in a macro-call or because its unused push it into the result vec,
734 // otherwise push the remapped tokens back into the queue as they can potentially be remapped again.
735 while let Some(token) = stack.pop() {
736 self.db.unwind_if_cancelled();
737 let was_not_remapped = (|| {
738 // are we inside an attribute macro call
739 let containing_attribute_macro_call = self.with_ctx(|ctx| {
740 token.value.ancestors().filter_map(ast::Item::cast).find_map(|item| {
741 if item.attrs().next().is_none() {
742 // Don't force populate the dyn cache for items that don't have an attribute anyways
745 Some((ctx.item_to_macro_call(token.with_value(item.clone()))?, item))
748 if let Some((call_id, item)) = containing_attribute_macro_call {
749 let file_id = call_id.as_file();
750 return process_expansion_for_token(
758 // or are we inside a function-like macro call
760 // FIXME replace map.while_some with take_while once stable
761 token.value.ancestors().map(ast::TokenTree::cast).while_some().last()
763 let parent = tt.syntax().parent()?;
764 // check for derive attribute here
765 let macro_call = match_ast! {
767 ast::MacroCall(mcall) => mcall,
768 // attribute we failed expansion for earlier, this might be a derive invocation
769 // so try downmapping the token into the pseudo derive expansion
770 // see [hir_expand::builtin_attr_macro] for how the pseudo derive expansion works
772 let attr = meta.parent_attr()?;
773 let adt = attr.syntax().parent().and_then(ast::Adt::cast)?;
774 let call_id = self.with_ctx(|ctx| {
775 let (_, call_id, _) = ctx.attr_to_derive_macro_call(
776 token.with_value(&adt),
777 token.with_value(attr),
781 let file_id = call_id.as_file();
782 return process_expansion_for_token(
793 if tt.left_delimiter_token().map_or(false, |it| it == token.value) {
796 if tt.right_delimiter_token().map_or(false, |it| it == token.value) {
800 let mcall = token.with_value(macro_call);
801 let file_id = match mcache.get(&mcall) {
804 let it = sa.expand(self.db, mcall.as_ref())?;
805 mcache.insert(mcall, it);
809 return process_expansion_for_token(&mut stack, file_id, None, token.as_ref());
812 // outside of a macro invocation so this is a "final" token
817 if was_not_remapped && f(token) {
823 // Note this return type is deliberate as [`find_nodes_at_offset_with_descend`] wants to stop
824 // traversing the inner iterator when it finds a node.
825 // The outer iterator is over the tokens descendants
826 // The inner iterator is the ancestors of a descendant
827 fn descend_node_at_offset(
831 ) -> impl Iterator<Item = impl Iterator<Item = SyntaxNode> + '_> + '_ {
832 node.token_at_offset(offset)
833 .map(move |token| self.descend_into_macros(token))
835 descendants.into_iter().map(move |it| self.token_ancestors_with_macros(it))
837 // re-order the tokens from token_at_offset by returning the ancestors with the smaller first nodes first
838 // See algo::ancestors_at_offset, which uses the same approach
839 .kmerge_by(|left, right| {
841 .map(|node| node.text_range().len())
842 .lt(right.clone().map(|node| node.text_range().len()))
846 fn original_range(&self, node: &SyntaxNode) -> FileRange {
847 let node = self.find_file(node);
848 node.original_file_range(self.db.upcast())
851 fn original_range_opt(&self, node: &SyntaxNode) -> Option<FileRange> {
852 let node = self.find_file(node);
853 node.original_file_range_opt(self.db.upcast())
856 fn original_ast_node<N: AstNode>(&self, node: N) -> Option<N> {
857 self.wrap_node_infile(node).original_ast_node(self.db.upcast()).map(|it| it.value)
860 fn diagnostics_display_range(&self, src: InFile<SyntaxNodePtr>) -> FileRange {
861 let root = self.parse_or_expand(src.file_id).unwrap();
862 let node = src.map(|it| it.to_node(&root));
863 node.as_ref().original_file_range(self.db.upcast())
866 fn token_ancestors_with_macros(
869 ) -> impl Iterator<Item = SyntaxNode> + Clone + '_ {
870 token.parent().into_iter().flat_map(move |parent| self.ancestors_with_macros(parent))
873 fn ancestors_with_macros(
876 ) -> impl Iterator<Item = SyntaxNode> + Clone + '_ {
877 let node = self.find_file(&node);
878 let db = self.db.upcast();
879 iter::successors(Some(node.cloned()), move |&InFile { file_id, ref value }| {
880 match value.parent() {
881 Some(parent) => Some(InFile::new(file_id, parent)),
883 self.cache(value.clone(), file_id);
884 file_id.call_node(db)
891 fn ancestors_at_offset_with_macros(
895 ) -> impl Iterator<Item = SyntaxNode> + '_ {
896 node.token_at_offset(offset)
897 .map(|token| self.token_ancestors_with_macros(token))
898 .kmerge_by(|node1, node2| node1.text_range().len() < node2.text_range().len())
901 fn resolve_lifetime_param(&self, lifetime: &ast::Lifetime) -> Option<LifetimeParam> {
902 let text = lifetime.text();
903 let lifetime_param = lifetime.syntax().ancestors().find_map(|syn| {
904 let gpl = ast::AnyHasGenericParams::cast(syn)?.generic_param_list()?;
905 gpl.lifetime_params()
906 .find(|tp| tp.lifetime().as_ref().map(|lt| lt.text()).as_ref() == Some(&text))
908 let src = self.wrap_node_infile(lifetime_param);
909 ToDef::to_def(self, src)
912 fn resolve_label(&self, lifetime: &ast::Lifetime) -> Option<Label> {
913 let text = lifetime.text();
914 let label = lifetime.syntax().ancestors().find_map(|syn| {
915 let label = match_ast! {
917 ast::ForExpr(it) => it.label(),
918 ast::WhileExpr(it) => it.label(),
919 ast::LoopExpr(it) => it.label(),
920 ast::BlockExpr(it) => it.label(),
926 .and_then(|lt| lt.lifetime_ident_token())
927 .map_or(false, |lt| lt.text() == text)
930 let src = self.wrap_node_infile(label);
931 ToDef::to_def(self, src)
934 fn resolve_type(&self, ty: &ast::Type) -> Option<Type> {
935 let analyze = self.analyze(ty.syntax())?;
936 let ctx = body::LowerCtx::new(self.db.upcast(), analyze.file_id);
937 let ty = hir_ty::TyLoweringContext::new(self.db, &analyze.resolver)
938 .lower_ty(&crate::TypeRef::from_ast(&ctx, ty.clone()));
939 Some(Type::new_with_resolver(self.db, &analyze.resolver, ty))
942 fn is_implicit_reborrow(&self, expr: &ast::Expr) -> Option<Mutability> {
943 self.analyze(expr.syntax())?.is_implicit_reborrow(self.db, expr)
946 fn type_of_expr(&self, expr: &ast::Expr) -> Option<TypeInfo> {
947 self.analyze(expr.syntax())?
948 .type_of_expr(self.db, expr)
949 .map(|(ty, coerced)| TypeInfo { original: ty, adjusted: coerced })
952 fn type_of_pat(&self, pat: &ast::Pat) -> Option<TypeInfo> {
953 self.analyze(pat.syntax())?
954 .type_of_pat(self.db, pat)
955 .map(|(ty, coerced)| TypeInfo { original: ty, adjusted: coerced })
958 fn type_of_self(&self, param: &ast::SelfParam) -> Option<Type> {
959 self.analyze(param.syntax())?.type_of_self(self.db, param)
962 fn pattern_adjustments(&self, pat: &ast::Pat) -> SmallVec<[Type; 1]> {
963 self.analyze(pat.syntax())
964 .and_then(|it| it.pattern_adjustments(self.db, pat))
968 fn binding_mode_of_pat(&self, pat: &ast::IdentPat) -> Option<BindingMode> {
969 self.analyze(pat.syntax())?.binding_mode_of_pat(self.db, pat)
972 fn resolve_method_call(&self, call: &ast::MethodCallExpr) -> Option<FunctionId> {
973 self.analyze(call.syntax())?.resolve_method_call(self.db, call).map(|(id, _)| id)
976 fn resolve_method_call_as_callable(&self, call: &ast::MethodCallExpr) -> Option<Callable> {
977 let source_analyzer = self.analyze(call.syntax())?;
978 let (func, subst) = source_analyzer.resolve_method_call(self.db, call)?;
979 let ty = self.db.value_ty(func.into()).substitute(Interner, &subst);
980 let resolver = source_analyzer.resolver;
981 let ty = Type::new_with_resolver(self.db, &resolver, ty);
982 let mut res = ty.as_callable(self.db)?;
983 res.is_bound_method = true;
987 fn resolve_field(&self, field: &ast::FieldExpr) -> Option<Field> {
988 self.analyze(field.syntax())?.resolve_field(self.db, field)
991 fn resolve_record_field(
993 field: &ast::RecordExprField,
994 ) -> Option<(Field, Option<Local>, Type)> {
995 self.analyze(field.syntax())?.resolve_record_field(self.db, field)
998 fn resolve_record_pat_field(&self, field: &ast::RecordPatField) -> Option<Field> {
999 self.analyze(field.syntax())?.resolve_record_pat_field(self.db, field)
1002 fn resolve_macro_call(&self, macro_call: &ast::MacroCall) -> Option<Macro> {
1003 let sa = self.analyze(macro_call.syntax())?;
1004 let macro_call = self.find_file(macro_call.syntax()).with_value(macro_call);
1005 sa.resolve_macro_call(self.db, macro_call)
1008 fn is_unsafe_macro_call(&self, macro_call: &ast::MacroCall) -> bool {
1009 let sa = match self.analyze(macro_call.syntax()) {
1011 None => return false,
1013 let macro_call = self.find_file(macro_call.syntax()).with_value(macro_call);
1014 sa.is_unsafe_macro_call(self.db, macro_call)
1017 fn resolve_attr_macro_call(&self, item: &ast::Item) -> Option<Macro> {
1018 let item_in_file = self.wrap_node_infile(item.clone());
1019 let id = self.with_ctx(|ctx| {
1020 let macro_call_id = ctx.item_to_macro_call(item_in_file)?;
1021 macro_call_to_macro_id(ctx, self.db.upcast(), macro_call_id)
1026 fn resolve_path(&self, path: &ast::Path) -> Option<PathResolution> {
1027 self.analyze(path.syntax())?.resolve_path(self.db, path)
1030 fn resolve_extern_crate(&self, extern_crate: &ast::ExternCrate) -> Option<Crate> {
1031 let krate = self.scope(extern_crate.syntax())?.krate();
1032 let name = extern_crate.name_ref()?.as_name();
1033 if name == known::SELF_PARAM {
1037 .dependencies(self.db)
1039 .find_map(|dep| (dep.name == name).then(|| dep.krate))
1042 fn resolve_variant(&self, record_lit: ast::RecordExpr) -> Option<VariantId> {
1043 self.analyze(record_lit.syntax())?.resolve_variant(self.db, record_lit)
1046 fn resolve_bind_pat_to_const(&self, pat: &ast::IdentPat) -> Option<ModuleDef> {
1047 self.analyze(pat.syntax())?.resolve_bind_pat_to_const(self.db, pat)
1050 fn record_literal_missing_fields(&self, literal: &ast::RecordExpr) -> Vec<(Field, Type)> {
1051 self.analyze(literal.syntax())
1052 .and_then(|it| it.record_literal_missing_fields(self.db, literal))
1053 .unwrap_or_default()
1056 fn record_pattern_missing_fields(&self, pattern: &ast::RecordPat) -> Vec<(Field, Type)> {
1057 self.analyze(pattern.syntax())
1058 .and_then(|it| it.record_pattern_missing_fields(self.db, pattern))
1059 .unwrap_or_default()
1062 fn with_ctx<F: FnOnce(&mut SourceToDefCtx) -> T, T>(&self, f: F) -> T {
1063 let mut cache = self.s2d_cache.borrow_mut();
1064 let mut ctx = SourceToDefCtx { db: self.db, cache: &mut *cache };
1068 fn to_module_def(&self, file: FileId) -> impl Iterator<Item = Module> {
1069 self.with_ctx(|ctx| ctx.file_to_def(file)).into_iter().map(Module::from)
1072 fn scope(&self, node: &SyntaxNode) -> Option<SemanticsScope<'db>> {
1073 self.analyze_no_infer(node).map(|SourceAnalyzer { file_id, resolver, .. }| SemanticsScope {
1080 fn scope_at_offset(&self, node: &SyntaxNode, offset: TextSize) -> Option<SemanticsScope<'db>> {
1081 self.analyze_with_offset_no_infer(node, offset).map(
1082 |SourceAnalyzer { file_id, resolver, .. }| SemanticsScope {
1090 fn scope_for_def(&self, def: Trait) -> SemanticsScope<'db> {
1091 let file_id = self.db.lookup_intern_trait(def.id).id.file_id();
1092 let resolver = def.id.resolver(self.db.upcast());
1093 SemanticsScope { db: self.db, file_id, resolver }
1096 fn source<Def: HasSource>(&self, def: Def) -> Option<InFile<Def::Ast>>
1100 let res = def.source(self.db)?;
1101 self.cache(find_root(res.value.syntax()), res.file_id);
1105 /// Returns none if the file of the node is not part of a crate.
1106 fn analyze(&self, node: &SyntaxNode) -> Option<SourceAnalyzer> {
1107 self.analyze_impl(node, None, true)
1110 /// Returns none if the file of the node is not part of a crate.
1111 fn analyze_no_infer(&self, node: &SyntaxNode) -> Option<SourceAnalyzer> {
1112 self.analyze_impl(node, None, false)
1115 fn analyze_with_offset_no_infer(
1119 ) -> Option<SourceAnalyzer> {
1120 self.analyze_impl(node, Some(offset), false)
1126 offset: Option<TextSize>,
1128 ) -> Option<SourceAnalyzer> {
1129 let _p = profile::span("Semantics::analyze_impl");
1130 let node = self.find_file(node);
1132 let container = match self.with_ctx(|ctx| ctx.find_container(node)) {
1134 None => return None,
1137 let resolver = match container {
1138 ChildContainer::DefWithBodyId(def) => {
1139 return Some(if infer_body {
1140 SourceAnalyzer::new_for_body(self.db, def, node, offset)
1142 SourceAnalyzer::new_for_body_no_infer(self.db, def, node, offset)
1145 ChildContainer::TraitId(it) => it.resolver(self.db.upcast()),
1146 ChildContainer::ImplId(it) => it.resolver(self.db.upcast()),
1147 ChildContainer::ModuleId(it) => it.resolver(self.db.upcast()),
1148 ChildContainer::EnumId(it) => it.resolver(self.db.upcast()),
1149 ChildContainer::VariantId(it) => it.resolver(self.db.upcast()),
1150 ChildContainer::TypeAliasId(it) => it.resolver(self.db.upcast()),
1151 ChildContainer::GenericDefId(it) => it.resolver(self.db.upcast()),
1153 Some(SourceAnalyzer::new_for_resolver(resolver, node))
1156 fn cache(&self, root_node: SyntaxNode, file_id: HirFileId) {
1157 assert!(root_node.parent().is_none());
1158 let mut cache = self.cache.borrow_mut();
1159 let prev = cache.insert(root_node, file_id);
1160 assert!(prev == None || prev == Some(file_id))
1163 fn assert_contains_node(&self, node: &SyntaxNode) {
1164 self.find_file(node);
1167 fn lookup(&self, root_node: &SyntaxNode) -> Option<HirFileId> {
1168 let cache = self.cache.borrow();
1169 cache.get(root_node).copied()
1172 fn wrap_node_infile<N: AstNode>(&self, node: N) -> InFile<N> {
1173 let InFile { file_id, .. } = self.find_file(node.syntax());
1174 InFile::new(file_id, node)
1177 /// Wraps the node in a [`InFile`] with the file id it belongs to.
1178 fn find_file<'node>(&self, node: &'node SyntaxNode) -> InFile<&'node SyntaxNode> {
1179 let root_node = find_root(node);
1180 let file_id = self.lookup(&root_node).unwrap_or_else(|| {
1182 "\n\nFailed to lookup {:?} in this Semantics.\n\
1183 Make sure to use only query nodes, derived from this instance of Semantics.\n\
1185 known nodes: {}\n\n",
1191 .map(|it| format!("{:?}", it))
1192 .collect::<Vec<_>>()
1196 InFile::new(file_id, node)
1199 fn is_unsafe_method_call(&self, method_call_expr: &ast::MethodCallExpr) -> bool {
1203 let field_expr = match expr {
1204 ast::Expr::FieldExpr(field_expr) => field_expr,
1207 let ty = self.type_of_expr(&field_expr.expr()?)?.original;
1208 if !ty.is_packed(self.db) {
1212 let func = self.resolve_method_call(method_call_expr).map(Function::from)?;
1213 let res = match func.self_param(self.db)?.access(self.db) {
1214 Access::Shared | Access::Exclusive => true,
1215 Access::Owned => false,
1222 fn is_unsafe_ref_expr(&self, ref_expr: &ast::RefExpr) -> bool {
1226 let field_expr = match expr {
1227 ast::Expr::FieldExpr(field_expr) => field_expr,
1230 let expr = field_expr.expr()?;
1231 self.type_of_expr(&expr)
1233 // Binding a reference to a packed type is possibly unsafe.
1234 .map(|ty| ty.original.is_packed(self.db))
1237 // FIXME This needs layout computation to be correct. It will highlight
1238 // more than it should with the current implementation.
1241 fn is_unsafe_ident_pat(&self, ident_pat: &ast::IdentPat) -> bool {
1242 if ident_pat.ref_token().is_none() {
1249 .and_then(|parent| {
1250 // `IdentPat` can live under `RecordPat` directly under `RecordPatField` or
1251 // `RecordPatFieldList`. `RecordPatField` also lives under `RecordPatFieldList`,
1252 // so this tries to lookup the `IdentPat` anywhere along that structure to the
1253 // `RecordPat` so we can get the containing type.
1254 let record_pat = ast::RecordPatField::cast(parent.clone())
1255 .and_then(|record_pat| record_pat.syntax().parent())
1256 .or_else(|| Some(parent.clone()))
1257 .and_then(|parent| {
1258 ast::RecordPatFieldList::cast(parent)?
1261 .and_then(ast::RecordPat::cast)
1264 // If this doesn't match a `RecordPat`, fallback to a `LetStmt` to see if
1265 // this is initialized from a `FieldExpr`.
1266 if let Some(record_pat) = record_pat {
1267 self.type_of_pat(&ast::Pat::RecordPat(record_pat))
1268 } else if let Some(let_stmt) = ast::LetStmt::cast(parent) {
1269 let field_expr = match let_stmt.initializer()? {
1270 ast::Expr::FieldExpr(field_expr) => field_expr,
1274 self.type_of_expr(&field_expr.expr()?)
1279 // Binding a reference to a packed type is possibly unsafe.
1280 .map(|ty| ty.original.is_packed(self.db))
1285 fn macro_call_to_macro_id(
1286 ctx: &mut SourceToDefCtx,
1287 db: &dyn AstDatabase,
1288 macro_call_id: MacroCallId,
1289 ) -> Option<MacroId> {
1290 let loc = db.lookup_intern_macro_call(macro_call_id);
1291 match loc.def.kind {
1292 hir_expand::MacroDefKind::Declarative(it)
1293 | hir_expand::MacroDefKind::BuiltIn(_, it)
1294 | hir_expand::MacroDefKind::BuiltInAttr(_, it)
1295 | hir_expand::MacroDefKind::BuiltInDerive(_, it)
1296 | hir_expand::MacroDefKind::BuiltInEager(_, it) => {
1297 ctx.macro_to_def(InFile::new(it.file_id, it.to_node(db)))
1299 hir_expand::MacroDefKind::ProcMacro(_, _, it) => {
1300 ctx.proc_macro_to_def(InFile::new(it.file_id, it.to_node(db)))
1305 pub trait ToDef: AstNode + Clone {
1308 fn to_def(sema: &SemanticsImpl, src: InFile<Self>) -> Option<Self::Def>;
1311 macro_rules! to_def_impls {
1312 ($(($def:path, $ast:path, $meth:ident)),* ,) => {$(
1313 impl ToDef for $ast {
1315 fn to_def(sema: &SemanticsImpl, src: InFile<Self>) -> Option<Self::Def> {
1316 sema.with_ctx(|ctx| ctx.$meth(src)).map(<$def>::from)
1323 (crate::Module, ast::Module, module_to_def),
1324 (crate::Module, ast::SourceFile, source_file_to_def),
1325 (crate::Struct, ast::Struct, struct_to_def),
1326 (crate::Enum, ast::Enum, enum_to_def),
1327 (crate::Union, ast::Union, union_to_def),
1328 (crate::Trait, ast::Trait, trait_to_def),
1329 (crate::Impl, ast::Impl, impl_to_def),
1330 (crate::TypeAlias, ast::TypeAlias, type_alias_to_def),
1331 (crate::Const, ast::Const, const_to_def),
1332 (crate::Static, ast::Static, static_to_def),
1333 (crate::Function, ast::Fn, fn_to_def),
1334 (crate::Field, ast::RecordField, record_field_to_def),
1335 (crate::Field, ast::TupleField, tuple_field_to_def),
1336 (crate::Variant, ast::Variant, enum_variant_to_def),
1337 (crate::TypeParam, ast::TypeParam, type_param_to_def),
1338 (crate::LifetimeParam, ast::LifetimeParam, lifetime_param_to_def),
1339 (crate::ConstParam, ast::ConstParam, const_param_to_def),
1340 (crate::GenericParam, ast::GenericParam, generic_param_to_def),
1341 (crate::Macro, ast::Macro, macro_to_def),
1342 (crate::Local, ast::IdentPat, bind_pat_to_def),
1343 (crate::Local, ast::SelfParam, self_param_to_def),
1344 (crate::Label, ast::Label, label_to_def),
1345 (crate::Adt, ast::Adt, adt_to_def),
1348 fn find_root(node: &SyntaxNode) -> SyntaxNode {
1349 node.ancestors().last().unwrap()
1352 /// `SemanticScope` encapsulates the notion of a scope (the set of visible
1353 /// names) at a particular program point.
1355 /// It is a bit tricky, as scopes do not really exist inside the compiler.
1356 /// Rather, the compiler directly computes for each reference the definition it
1357 /// refers to. It might transiently compute the explicit scope map while doing
1358 /// so, but, generally, this is not something left after the analysis.
1360 /// However, we do very much need explicit scopes for IDE purposes --
1361 /// completion, at its core, lists the contents of the current scope. The notion
1362 /// of scope is also useful to answer questions like "what would be the meaning
1363 /// of this piece of code if we inserted it into this position?".
1365 /// So `SemanticsScope` is constructed from a specific program point (a syntax
1366 /// node or just a raw offset) and provides access to the set of visible names
1367 /// on a somewhat best-effort basis.
1369 /// Note that if you are wondering "what does this specific existing name mean?",
1370 /// you'd better use the `resolve_` family of methods.
1372 pub struct SemanticsScope<'a> {
1373 pub db: &'a dyn HirDatabase,
1378 impl<'a> SemanticsScope<'a> {
1379 pub fn module(&self) -> Module {
1380 Module { id: self.resolver.module() }
1383 pub fn krate(&self) -> Crate {
1384 Crate { id: self.resolver.krate() }
1387 pub(crate) fn resolver(&self) -> &Resolver {
1391 /// Note: `VisibleTraits` should be treated as an opaque type, passed into `Type
1392 pub fn visible_traits(&self) -> VisibleTraits {
1393 let resolver = &self.resolver;
1394 VisibleTraits(resolver.traits_in_scope(self.db.upcast()))
1397 pub fn process_all_names(&self, f: &mut dyn FnMut(Name, ScopeDef)) {
1398 let scope = self.resolver.names_in_scope(self.db.upcast());
1399 for (name, entries) in scope {
1400 for entry in entries {
1401 let def = match entry {
1402 resolver::ScopeDef::ModuleDef(it) => ScopeDef::ModuleDef(it.into()),
1403 resolver::ScopeDef::Unknown => ScopeDef::Unknown,
1404 resolver::ScopeDef::ImplSelfType(it) => ScopeDef::ImplSelfType(it.into()),
1405 resolver::ScopeDef::AdtSelfType(it) => ScopeDef::AdtSelfType(it.into()),
1406 resolver::ScopeDef::GenericParam(id) => ScopeDef::GenericParam(id.into()),
1407 resolver::ScopeDef::Local(pat_id) => match self.resolver.body_owner() {
1408 Some(parent) => ScopeDef::Local(Local { parent, pat_id }),
1411 resolver::ScopeDef::Label(label_id) => match self.resolver.body_owner() {
1412 Some(parent) => ScopeDef::Label(Label { parent, label_id }),
1416 f(name.clone(), def)
1421 /// Resolve a path as-if it was written at the given scope. This is
1422 /// necessary a heuristic, as it doesn't take hygiene into account.
1423 pub fn speculative_resolve(&self, path: &ast::Path) -> Option<PathResolution> {
1424 let ctx = body::LowerCtx::new(self.db.upcast(), self.file_id);
1425 let path = Path::from_src(path.clone(), &ctx)?;
1426 resolve_hir_path(self.db, &self.resolver, &path)
1429 /// Iterates over associated types that may be specified after the given path (using
1430 /// `Ty::Assoc` syntax).
1431 pub fn assoc_type_shorthand_candidates<R>(
1433 resolution: &PathResolution,
1434 mut cb: impl FnMut(&Name, TypeAlias) -> Option<R>,
1436 let def = self.resolver.generic_def()?;
1437 hir_ty::associated_type_shorthand_candidates(
1440 resolution.in_type_ns()?,
1441 |name, _, id| cb(name, id.into()),
1446 pub struct VisibleTraits(pub FxHashSet<TraitId>);