1 use crate::{ImplTraitContext, Resolver};
2 use rustc_ast::visit::{self, FnKind};
3 use rustc_ast::walk_list;
5 use rustc_expand::expand::AstFragment;
6 use rustc_hir::def_id::LocalDefId;
7 use rustc_hir::definitions::*;
8 use rustc_span::hygiene::LocalExpnId;
9 use rustc_span::symbol::sym;
13 pub(crate) fn collect_definitions(
14 resolver: &mut Resolver<'_>,
15 fragment: &AstFragment,
16 expansion: LocalExpnId,
18 let (parent_def, impl_trait_context) = resolver.invocation_parents[&expansion];
19 fragment.visit_with(&mut DefCollector { resolver, parent_def, expansion, impl_trait_context });
22 /// Creates `DefId`s for nodes in the AST.
23 struct DefCollector<'a, 'b> {
24 resolver: &'a mut Resolver<'b>,
25 parent_def: LocalDefId,
26 impl_trait_context: ImplTraitContext,
27 expansion: LocalExpnId,
30 impl<'a, 'b> DefCollector<'a, 'b> {
31 fn create_def(&mut self, node_id: NodeId, data: DefPathData, span: Span) -> LocalDefId {
32 let parent_def = self.parent_def;
33 debug!("create_def(node_id={:?}, data={:?}, parent_def={:?})", node_id, data, parent_def);
34 self.resolver.create_def(
38 self.expansion.to_expn_id(),
39 span.with_parent(None),
43 fn with_parent<F: FnOnce(&mut Self)>(&mut self, parent_def: LocalDefId, f: F) {
44 let orig_parent_def = std::mem::replace(&mut self.parent_def, parent_def);
46 self.parent_def = orig_parent_def;
49 fn with_impl_trait<F: FnOnce(&mut Self)>(
51 impl_trait_context: ImplTraitContext,
54 let orig_itc = std::mem::replace(&mut self.impl_trait_context, impl_trait_context);
56 self.impl_trait_context = orig_itc;
59 fn collect_field(&mut self, field: &'a FieldDef, index: Option<usize>) {
60 let index = |this: &Self| {
61 index.unwrap_or_else(|| {
62 let node_id = NodeId::placeholder_from_expn_id(this.expansion);
63 this.resolver.placeholder_field_indices[&node_id]
67 if field.is_placeholder {
68 let old_index = self.resolver.placeholder_field_indices.insert(field.id, index(self));
69 assert!(old_index.is_none(), "placeholder field index is reset for a node ID");
70 self.visit_macro_invoc(field.id);
72 let name = field.ident.map_or_else(|| sym::integer(index(self)), |ident| ident.name);
73 let def = self.create_def(field.id, DefPathData::ValueNs(name), field.span);
74 self.with_parent(def, |this| visit::walk_field_def(this, field));
78 fn visit_macro_invoc(&mut self, id: NodeId) {
79 let id = id.placeholder_to_expn_id();
81 self.resolver.invocation_parents.insert(id, (self.parent_def, self.impl_trait_context));
82 assert!(old_parent.is_none(), "parent `LocalDefId` is reset for an invocation");
86 impl<'a, 'b> visit::Visitor<'a> for DefCollector<'a, 'b> {
87 fn visit_item(&mut self, i: &'a Item) {
88 debug!("visit_item: {:?}", i);
90 // Pick the def data. This need not be unique, but the more
91 // information we encapsulate into, the better
92 let def_data = match &i.kind {
93 ItemKind::Impl { .. } => DefPathData::Impl,
94 ItemKind::ForeignMod(..) => DefPathData::ForeignMod,
97 | ItemKind::TraitAlias(..)
99 | ItemKind::Struct(..)
100 | ItemKind::Union(..)
101 | ItemKind::ExternCrate(..)
102 | ItemKind::TyAlias(..) => DefPathData::TypeNs(i.ident.name),
103 ItemKind::Static(..) | ItemKind::Const(..) | ItemKind::Fn(..) => {
104 DefPathData::ValueNs(i.ident.name)
106 ItemKind::MacroDef(..) => DefPathData::MacroNs(i.ident.name),
107 ItemKind::MacCall(..) => {
108 visit::walk_item(self, i);
109 return self.visit_macro_invoc(i.id);
111 ItemKind::GlobalAsm(..) => DefPathData::GlobalAsm,
112 ItemKind::Use(..) => {
113 return visit::walk_item(self, i);
116 let def = self.create_def(i.id, def_data, i.span);
118 self.with_parent(def, |this| {
119 this.with_impl_trait(ImplTraitContext::Existential, |this| {
121 ItemKind::Struct(ref struct_def, _) | ItemKind::Union(ref struct_def, _) => {
122 // If this is a unit or tuple-like struct, register the constructor.
123 if let Some(ctor_hir_id) = struct_def.ctor_id() {
124 this.create_def(ctor_hir_id, DefPathData::Ctor, i.span);
129 visit::walk_item(this, i);
134 fn visit_fn(&mut self, fn_kind: FnKind<'a>, span: Span, _: NodeId) {
135 if let FnKind::Fn(_, _, sig, _, generics, body) = fn_kind {
136 if let Async::Yes { closure_id, return_impl_trait_id, .. } = sig.header.asyncness {
137 self.visit_generics(generics);
139 let return_impl_trait_id =
140 self.create_def(return_impl_trait_id, DefPathData::ImplTrait, span);
142 // For async functions, we need to create their inner defs inside of a
143 // closure to match their desugared representation. Besides that,
144 // we must mirror everything that `visit::walk_fn` below does.
145 self.visit_fn_header(&sig.header);
146 for param in &sig.decl.inputs {
147 self.visit_param(param);
149 self.with_parent(return_impl_trait_id, |this| {
150 this.visit_fn_ret_ty(&sig.decl.output)
152 let closure_def = self.create_def(closure_id, DefPathData::ClosureExpr, span);
153 self.with_parent(closure_def, |this| walk_list!(this, visit_block, body));
158 visit::walk_fn(self, fn_kind, span);
161 fn visit_use_tree(&mut self, use_tree: &'a UseTree, id: NodeId, _nested: bool) {
162 self.create_def(id, DefPathData::Use, use_tree.span);
163 match use_tree.kind {
164 UseTreeKind::Simple(_, id1, id2) => {
165 self.create_def(id1, DefPathData::Use, use_tree.prefix.span);
166 self.create_def(id2, DefPathData::Use, use_tree.prefix.span);
168 UseTreeKind::Glob => (),
169 UseTreeKind::Nested(..) => {}
171 visit::walk_use_tree(self, use_tree, id);
174 fn visit_foreign_item(&mut self, foreign_item: &'a ForeignItem) {
175 if let ForeignItemKind::MacCall(_) = foreign_item.kind {
176 return self.visit_macro_invoc(foreign_item.id);
179 let def = self.create_def(
181 DefPathData::ValueNs(foreign_item.ident.name),
185 self.with_parent(def, |this| {
186 visit::walk_foreign_item(this, foreign_item);
190 fn visit_variant(&mut self, v: &'a Variant) {
191 if v.is_placeholder {
192 return self.visit_macro_invoc(v.id);
194 let def = self.create_def(v.id, DefPathData::TypeNs(v.ident.name), v.span);
195 self.with_parent(def, |this| {
196 if let Some(ctor_hir_id) = v.data.ctor_id() {
197 this.create_def(ctor_hir_id, DefPathData::Ctor, v.span);
199 visit::walk_variant(this, v)
203 fn visit_variant_data(&mut self, data: &'a VariantData) {
204 // The assumption here is that non-`cfg` macro expansion cannot change field indices.
205 // It currently holds because only inert attributes are accepted on fields,
206 // and every such attribute expands into a single field after it's resolved.
207 for (index, field) in data.fields().iter().enumerate() {
208 self.collect_field(field, Some(index));
212 fn visit_generic_param(&mut self, param: &'a GenericParam) {
213 if param.is_placeholder {
214 self.visit_macro_invoc(param.id);
217 let name = param.ident.name;
218 let def_path_data = match param.kind {
219 GenericParamKind::Lifetime { .. } => DefPathData::LifetimeNs(name),
220 GenericParamKind::Type { .. } => DefPathData::TypeNs(name),
221 GenericParamKind::Const { .. } => DefPathData::ValueNs(name),
223 self.create_def(param.id, def_path_data, param.ident.span);
225 // impl-Trait can happen inside generic parameters, like
227 // fn foo<U: Iterator<Item = impl Clone>>() {}
230 // In that case, the impl-trait is lowered as an additional generic parameter.
231 self.with_impl_trait(ImplTraitContext::Universal(self.parent_def), |this| {
232 visit::walk_generic_param(this, param)
236 fn visit_assoc_item(&mut self, i: &'a AssocItem, ctxt: visit::AssocCtxt) {
237 let def_data = match &i.kind {
238 AssocItemKind::Fn(..) | AssocItemKind::Const(..) => DefPathData::ValueNs(i.ident.name),
239 AssocItemKind::TyAlias(..) => DefPathData::TypeNs(i.ident.name),
240 AssocItemKind::MacCall(..) => return self.visit_macro_invoc(i.id),
243 let def = self.create_def(i.id, def_data, i.span);
244 self.with_parent(def, |this| visit::walk_assoc_item(this, i, ctxt));
247 fn visit_pat(&mut self, pat: &'a Pat) {
249 PatKind::MacCall(..) => self.visit_macro_invoc(pat.id),
250 _ => visit::walk_pat(self, pat),
254 fn visit_anon_const(&mut self, constant: &'a AnonConst) {
255 let def = self.create_def(constant.id, DefPathData::AnonConst, constant.value.span);
256 self.with_parent(def, |this| visit::walk_anon_const(this, constant));
259 fn visit_expr(&mut self, expr: &'a Expr) {
260 let parent_def = match expr.kind {
261 ExprKind::MacCall(..) => return self.visit_macro_invoc(expr.id),
262 ExprKind::Closure(_, _, asyncness, ..) => {
263 // Async closures desugar to closures inside of closures, so
264 // we must create two defs.
265 let closure_def = self.create_def(expr.id, DefPathData::ClosureExpr, expr.span);
267 Async::Yes { closure_id, .. } => {
268 self.create_def(closure_id, DefPathData::ClosureExpr, expr.span)
270 Async::No => closure_def,
273 ExprKind::Async(_, async_id, _) => {
274 self.create_def(async_id, DefPathData::ClosureExpr, expr.span)
276 _ => self.parent_def,
279 self.with_parent(parent_def, |this| visit::walk_expr(this, expr));
282 fn visit_ty(&mut self, ty: &'a Ty) {
284 TyKind::MacCall(..) => self.visit_macro_invoc(ty.id),
285 TyKind::ImplTrait(node_id, _) => {
286 let parent_def = match self.impl_trait_context {
287 ImplTraitContext::Universal(item_def) => self.resolver.create_def(
290 DefPathData::ImplTrait,
291 self.expansion.to_expn_id(),
294 ImplTraitContext::Existential => {
295 self.create_def(node_id, DefPathData::ImplTrait, ty.span)
298 self.with_parent(parent_def, |this| visit::walk_ty(this, ty))
300 _ => visit::walk_ty(self, ty),
304 fn visit_stmt(&mut self, stmt: &'a Stmt) {
306 StmtKind::MacCall(..) => self.visit_macro_invoc(stmt.id),
307 _ => visit::walk_stmt(self, stmt),
311 fn visit_arm(&mut self, arm: &'a Arm) {
312 if arm.is_placeholder { self.visit_macro_invoc(arm.id) } else { visit::walk_arm(self, arm) }
315 fn visit_expr_field(&mut self, f: &'a ExprField) {
316 if f.is_placeholder {
317 self.visit_macro_invoc(f.id)
319 visit::walk_expr_field(self, f)
323 fn visit_pat_field(&mut self, fp: &'a PatField) {
324 if fp.is_placeholder {
325 self.visit_macro_invoc(fp.id)
327 visit::walk_pat_field(self, fp)
331 fn visit_param(&mut self, p: &'a Param) {
332 if p.is_placeholder {
333 self.visit_macro_invoc(p.id)
335 self.with_impl_trait(ImplTraitContext::Universal(self.parent_def), |this| {
336 visit::walk_param(this, p)
341 // This method is called only when we are visiting an individual field
342 // after expanding an attribute on it.
343 fn visit_field_def(&mut self, field: &'a FieldDef) {
344 self.collect_field(field, None);
347 fn visit_crate(&mut self, krate: &'a Crate) {
348 if krate.is_placeholder {
349 self.visit_macro_invoc(krate.id)
351 visit::walk_crate(self, krate)