1 use crate::{ImplTraitContext, Resolver};
2 use rustc_ast::visit::{self, FnKind};
3 use rustc_ast::walk_list;
5 use rustc_ast_lowering::ResolverAstLowering;
6 use rustc_expand::expand::AstFragment;
7 use rustc_hir::def_id::LocalDefId;
8 use rustc_hir::definitions::*;
9 use rustc_span::hygiene::LocalExpnId;
10 use rustc_span::symbol::{kw, sym};
14 crate fn collect_definitions(
15 resolver: &mut Resolver<'_>,
16 fragment: &AstFragment,
17 expansion: LocalExpnId,
19 let (parent_def, impl_trait_context) = resolver.invocation_parents[&expansion];
20 fragment.visit_with(&mut DefCollector { resolver, parent_def, expansion, impl_trait_context });
23 /// Creates `DefId`s for nodes in the AST.
24 struct DefCollector<'a, 'b> {
25 resolver: &'a mut Resolver<'b>,
26 parent_def: LocalDefId,
27 impl_trait_context: ImplTraitContext,
28 expansion: LocalExpnId,
31 impl<'a, 'b> DefCollector<'a, 'b> {
32 fn create_def(&mut self, node_id: NodeId, data: DefPathData, span: Span) -> LocalDefId {
33 let parent_def = self.parent_def;
34 debug!("create_def(node_id={:?}, data={:?}, parent_def={:?})", node_id, data, parent_def);
35 self.resolver.create_def(
39 self.expansion.to_expn_id(),
40 span.with_parent(None),
44 fn with_parent<F: FnOnce(&mut Self)>(&mut self, parent_def: LocalDefId, f: F) {
45 let orig_parent_def = std::mem::replace(&mut self.parent_def, parent_def);
47 self.parent_def = orig_parent_def;
50 fn with_impl_trait<F: FnOnce(&mut Self)>(
52 impl_trait_context: ImplTraitContext,
55 let orig_itc = std::mem::replace(&mut self.impl_trait_context, impl_trait_context);
57 self.impl_trait_context = orig_itc;
60 fn collect_field(&mut self, field: &'a FieldDef, index: Option<usize>) {
61 let index = |this: &Self| {
62 index.unwrap_or_else(|| {
63 let node_id = NodeId::placeholder_from_expn_id(this.expansion);
64 this.resolver.placeholder_field_indices[&node_id]
68 if field.is_placeholder {
69 let old_index = self.resolver.placeholder_field_indices.insert(field.id, index(self));
70 assert!(old_index.is_none(), "placeholder field index is reset for a node ID");
71 self.visit_macro_invoc(field.id);
73 let name = field.ident.map_or_else(|| sym::integer(index(self)), |ident| ident.name);
74 let def = self.create_def(field.id, DefPathData::ValueNs(name), field.span);
75 self.with_parent(def, |this| visit::walk_field_def(this, field));
79 fn visit_macro_invoc(&mut self, id: NodeId) {
80 let id = id.placeholder_to_expn_id();
82 self.resolver.invocation_parents.insert(id, (self.parent_def, self.impl_trait_context));
83 assert!(old_parent.is_none(), "parent `LocalDefId` is reset for an invocation");
87 impl<'a, 'b> visit::Visitor<'a> for DefCollector<'a, 'b> {
88 fn visit_item(&mut self, i: &'a Item) {
89 debug!("visit_item: {:?}", i);
91 // Pick the def data. This need not be unique, but the more
92 // information we encapsulate into, the better
93 let def_data = match &i.kind {
94 ItemKind::Impl { .. } => DefPathData::Impl,
95 ItemKind::Mod(..) if i.ident.name == kw::Empty => {
96 // Fake crate root item from expand.
97 return visit::walk_item(self, i);
100 | ItemKind::Trait(..)
101 | ItemKind::TraitAlias(..)
103 | ItemKind::Struct(..)
104 | ItemKind::Union(..)
105 | ItemKind::ExternCrate(..)
106 | ItemKind::ForeignMod(..)
107 | ItemKind::TyAlias(..) => DefPathData::TypeNs(i.ident.name),
108 ItemKind::Static(..) | ItemKind::Const(..) | ItemKind::Fn(..) => {
109 DefPathData::ValueNs(i.ident.name)
111 ItemKind::MacroDef(..) => DefPathData::MacroNs(i.ident.name),
112 ItemKind::MacCall(..) => {
113 visit::walk_item(self, i);
114 return self.visit_macro_invoc(i.id);
116 ItemKind::GlobalAsm(..) => DefPathData::Misc,
117 ItemKind::Use(..) => {
118 return visit::walk_item(self, i);
121 let def = self.create_def(i.id, def_data, i.span);
123 self.with_parent(def, |this| {
124 this.with_impl_trait(ImplTraitContext::Existential, |this| {
126 ItemKind::Struct(ref struct_def, _) | ItemKind::Union(ref struct_def, _) => {
127 // If this is a unit or tuple-like struct, register the constructor.
128 if let Some(ctor_hir_id) = struct_def.ctor_id() {
129 this.create_def(ctor_hir_id, DefPathData::Ctor, i.span);
134 visit::walk_item(this, i);
139 fn visit_fn(&mut self, fn_kind: FnKind<'a>, span: Span, _: NodeId) {
140 if let FnKind::Fn(_, _, sig, _, body) = fn_kind {
141 if let Async::Yes { closure_id, return_impl_trait_id, .. } = sig.header.asyncness {
142 let return_impl_trait_id =
143 self.create_def(return_impl_trait_id, DefPathData::ImplTrait, span);
145 // For async functions, we need to create their inner defs inside of a
146 // closure to match their desugared representation. Besides that,
147 // we must mirror everything that `visit::walk_fn` below does.
148 self.visit_fn_header(&sig.header);
149 for param in &sig.decl.inputs {
150 self.visit_param(param);
152 self.with_parent(return_impl_trait_id, |this| {
153 this.visit_fn_ret_ty(&sig.decl.output)
155 let closure_def = self.create_def(closure_id, DefPathData::ClosureExpr, span);
156 self.with_parent(closure_def, |this| walk_list!(this, visit_block, body));
161 visit::walk_fn(self, fn_kind, span);
164 fn visit_use_tree(&mut self, use_tree: &'a UseTree, id: NodeId, _nested: bool) {
165 self.create_def(id, DefPathData::Misc, use_tree.span);
166 match use_tree.kind {
167 UseTreeKind::Simple(_, id1, id2) => {
168 self.create_def(id1, DefPathData::Misc, use_tree.prefix.span);
169 self.create_def(id2, DefPathData::Misc, use_tree.prefix.span);
171 UseTreeKind::Glob => (),
172 UseTreeKind::Nested(..) => {}
174 visit::walk_use_tree(self, use_tree, id);
177 fn visit_foreign_item(&mut self, foreign_item: &'a ForeignItem) {
178 if let ForeignItemKind::MacCall(_) = foreign_item.kind {
179 return self.visit_macro_invoc(foreign_item.id);
182 let def = self.create_def(
184 DefPathData::ValueNs(foreign_item.ident.name),
188 self.with_parent(def, |this| {
189 visit::walk_foreign_item(this, foreign_item);
193 fn visit_variant(&mut self, v: &'a Variant) {
194 if v.is_placeholder {
195 return self.visit_macro_invoc(v.id);
197 let def = self.create_def(v.id, DefPathData::TypeNs(v.ident.name), v.span);
198 self.with_parent(def, |this| {
199 if let Some(ctor_hir_id) = v.data.ctor_id() {
200 this.create_def(ctor_hir_id, DefPathData::Ctor, v.span);
202 visit::walk_variant(this, v)
206 fn visit_variant_data(&mut self, data: &'a VariantData) {
207 // The assumption here is that non-`cfg` macro expansion cannot change field indices.
208 // It currently holds because only inert attributes are accepted on fields,
209 // and every such attribute expands into a single field after it's resolved.
210 for (index, field) in data.fields().iter().enumerate() {
211 self.collect_field(field, Some(index));
215 fn visit_generic_param(&mut self, param: &'a GenericParam) {
216 if param.is_placeholder {
217 self.visit_macro_invoc(param.id);
220 let name = param.ident.name;
221 let def_path_data = match param.kind {
222 GenericParamKind::Lifetime { .. } => DefPathData::LifetimeNs(name),
223 GenericParamKind::Type { .. } => DefPathData::TypeNs(name),
224 GenericParamKind::Const { .. } => DefPathData::ValueNs(name),
226 self.create_def(param.id, def_path_data, param.ident.span);
228 // impl-Trait can happen inside generic parameters, like
230 // fn foo<U: Iterator<Item = impl Clone>>() {}
233 // In that case, the impl-trait is lowered as an additional generic parameter.
234 self.with_impl_trait(ImplTraitContext::Universal(self.parent_def), |this| {
235 visit::walk_generic_param(this, param)
239 fn visit_assoc_item(&mut self, i: &'a AssocItem, ctxt: visit::AssocCtxt) {
240 let def_data = match &i.kind {
241 AssocItemKind::Fn(..) | AssocItemKind::Const(..) => DefPathData::ValueNs(i.ident.name),
242 AssocItemKind::TyAlias(..) => DefPathData::TypeNs(i.ident.name),
243 AssocItemKind::MacCall(..) => return self.visit_macro_invoc(i.id),
246 let def = self.create_def(i.id, def_data, i.span);
247 self.with_parent(def, |this| visit::walk_assoc_item(this, i, ctxt));
250 fn visit_pat(&mut self, pat: &'a Pat) {
252 PatKind::MacCall(..) => self.visit_macro_invoc(pat.id),
253 _ => visit::walk_pat(self, pat),
257 fn visit_anon_const(&mut self, constant: &'a AnonConst) {
258 let def = self.create_def(constant.id, DefPathData::AnonConst, constant.value.span);
259 self.with_parent(def, |this| visit::walk_anon_const(this, constant));
262 fn visit_expr(&mut self, expr: &'a Expr) {
263 let parent_def = match expr.kind {
264 ExprKind::MacCall(..) => return self.visit_macro_invoc(expr.id),
265 ExprKind::Closure(_, asyncness, ..) => {
266 // Async closures desugar to closures inside of closures, so
267 // we must create two defs.
268 let closure_def = self.create_def(expr.id, DefPathData::ClosureExpr, expr.span);
270 Async::Yes { closure_id, .. } => {
271 self.create_def(closure_id, DefPathData::ClosureExpr, expr.span)
273 Async::No => closure_def,
276 ExprKind::Async(_, async_id, _) => {
277 self.create_def(async_id, DefPathData::ClosureExpr, expr.span)
279 _ => self.parent_def,
282 self.with_parent(parent_def, |this| visit::walk_expr(this, expr));
285 fn visit_ty(&mut self, ty: &'a Ty) {
287 TyKind::MacCall(..) => self.visit_macro_invoc(ty.id),
288 TyKind::ImplTrait(node_id, _) => {
289 let parent_def = match self.impl_trait_context {
290 ImplTraitContext::Universal(item_def) => self.resolver.create_def(
293 DefPathData::ImplTrait,
294 self.expansion.to_expn_id(),
297 ImplTraitContext::Existential => {
298 self.create_def(node_id, DefPathData::ImplTrait, ty.span)
301 self.with_parent(parent_def, |this| visit::walk_ty(this, ty))
303 _ => visit::walk_ty(self, ty),
307 fn visit_stmt(&mut self, stmt: &'a Stmt) {
309 StmtKind::MacCall(..) => self.visit_macro_invoc(stmt.id),
310 _ => visit::walk_stmt(self, stmt),
314 fn visit_arm(&mut self, arm: &'a Arm) {
315 if arm.is_placeholder { self.visit_macro_invoc(arm.id) } else { visit::walk_arm(self, arm) }
318 fn visit_expr_field(&mut self, f: &'a ExprField) {
319 if f.is_placeholder {
320 self.visit_macro_invoc(f.id)
322 visit::walk_expr_field(self, f)
326 fn visit_pat_field(&mut self, fp: &'a PatField) {
327 if fp.is_placeholder {
328 self.visit_macro_invoc(fp.id)
330 visit::walk_pat_field(self, fp)
334 fn visit_param(&mut self, p: &'a Param) {
335 if p.is_placeholder {
336 self.visit_macro_invoc(p.id)
338 self.with_impl_trait(ImplTraitContext::Universal(self.parent_def), |this| {
339 visit::walk_param(this, p)
344 // This method is called only when we are visiting an individual field
345 // after expanding an attribute on it.
346 fn visit_field_def(&mut self, field: &'a FieldDef) {
347 self.collect_field(field, None);