3 use rustc_ast::visit::Visitor;
5 use rustc_ast::EnumDef;
6 use rustc_ast::ForeignMod;
8 use rustc_hir::def_id::LocalDefId;
9 use rustc_hir::def_id::CRATE_DEF_ID;
10 use rustc_middle::middle::privacy::AccessLevel;
11 use rustc_middle::ty::Visibility;
14 use crate::imports::ImportKind;
15 use crate::BindingKey;
16 use crate::NameBinding;
17 use crate::NameBindingKind;
20 pub struct AccessLevelsVisitor<'r, 'a> {
21 r: &'r mut Resolver<'a>,
22 prev_level: Option<AccessLevel>,
26 impl<'r, 'a> AccessLevelsVisitor<'r, 'a> {
27 /// Fills the `Resolver::access_levels` table with public & exported items
28 /// For now, this doesn't resolve macros (FIXME) and cannot resolve Impl, as we
29 /// need access to a TyCtxt for that.
30 pub fn compute_access_levels<'c>(r: &'r mut Resolver<'a>, krate: &'c Crate) {
32 AccessLevelsVisitor { r, changed: false, prev_level: Some(AccessLevel::Public) };
34 visitor.set_access_level_def_id(CRATE_DEF_ID, Some(AccessLevel::Public));
35 visitor.set_exports_access_level(CRATE_DEF_ID);
37 while visitor.changed {
39 visit::walk_crate(&mut visitor, krate);
42 tracing::info!("resolve::access_levels: {:#?}", r.access_levels);
47 self.prev_level = Some(AccessLevel::Public);
50 /// Update the access level of the exports of the given module accordingly. The module access
51 /// level has to be Exported or Public.
52 /// This will also follow `use` chains (see PrivacyVisitor::set_import_binding_access_level).
53 fn set_exports_access_level(&mut self, module_id: LocalDefId) {
54 assert!(self.r.module_map.contains_key(&&module_id.to_def_id()));
56 // Set the given binding access level to `AccessLevel::Public` and
57 // sets the rest of the `use` chain to `AccessLevel::Exported` until
58 // we hit the actual exported item.
59 let set_import_binding_access_level =
60 |this: &mut Self, mut binding: &NameBinding<'a>, mut access_level| {
61 while let NameBindingKind::Import { binding: nested_binding, import, .. } =
64 this.set_access_level(import.id, access_level);
65 if let ImportKind::Single { additional_ids, .. } = import.kind {
66 this.set_access_level(additional_ids.0, access_level);
67 this.set_access_level(additional_ids.1, access_level);
70 access_level = Some(AccessLevel::Exported);
71 binding = nested_binding;
75 let module_level = self.r.access_levels.map.get(&module_id).copied();
76 assert!(module_level >= Some(AccessLevel::Exported));
78 if let Some(exports) = self.r.reexport_map.get(&module_id) {
79 let pub_exports = exports
81 .filter(|ex| ex.vis == Visibility::Public)
85 let module = self.r.get_module(module_id.to_def_id()).unwrap();
86 for export in pub_exports.into_iter() {
87 if let Some(export_def_id) = export.res.opt_def_id().and_then(|id| id.as_local()) {
88 self.set_access_level_def_id(export_def_id, Some(AccessLevel::Exported));
91 if let Some(ns) = export.res.ns() {
92 let key = BindingKey { ident: export.ident, ns, disambiguator: 0 };
93 let name_res = self.r.resolution(module, key);
94 if let Some(binding) = name_res.borrow().binding() {
95 set_import_binding_access_level(self, binding, module_level)
102 /// Sets the access level of the `LocalDefId` corresponding to the given `NodeId`.
103 /// This function will panic if the `NodeId` does not have a `LocalDefId`
107 access_level: Option<AccessLevel>,
108 ) -> Option<AccessLevel> {
109 self.set_access_level_def_id(self.r.local_def_id(node_id), access_level)
112 fn set_access_level_def_id(
115 access_level: Option<AccessLevel>,
116 ) -> Option<AccessLevel> {
117 let old_level = self.r.access_levels.map.get(&def_id).copied();
118 if old_level < access_level {
119 self.r.access_levels.map.insert(def_id, access_level.unwrap());
128 impl<'r, 'ast> Visitor<'ast> for AccessLevelsVisitor<'ast, 'r> {
129 fn visit_item(&mut self, item: &'ast ast::Item) {
130 let inherited_item_level = match item.kind {
131 // Resolved in rustc_privacy when types are available
132 ast::ItemKind::Impl(..) => return,
134 // Only exported `macro_rules!` items are public, but they always are
135 ast::ItemKind::MacroDef(ref macro_def) if macro_def.macro_rules => {
136 let is_macro_export =
137 item.attrs.iter().any(|attr| attr.has_name(sym::macro_export));
138 if is_macro_export { Some(AccessLevel::Public) } else { None }
141 // Foreign modules inherit level from parents.
142 ast::ItemKind::ForeignMod(..) => self.prev_level,
144 // Other `pub` items inherit levels from parents.
145 ast::ItemKind::ExternCrate(..)
146 | ast::ItemKind::Use(..)
147 | ast::ItemKind::Static(..)
148 | ast::ItemKind::Const(..)
149 | ast::ItemKind::Fn(..)
150 | ast::ItemKind::Mod(..)
151 | ast::ItemKind::GlobalAsm(..)
152 | ast::ItemKind::TyAlias(..)
153 | ast::ItemKind::Enum(..)
154 | ast::ItemKind::Struct(..)
155 | ast::ItemKind::Union(..)
156 | ast::ItemKind::Trait(..)
157 | ast::ItemKind::TraitAlias(..)
158 | ast::ItemKind::MacroDef(..) => {
159 if item.vis.kind.is_pub() {
166 // Should be unreachable at this stage
167 ast::ItemKind::MacCall(..) => panic!(
168 "ast::ItemKind::MacCall encountered, this should not anymore appear at this stage"
172 let access_level = self.set_access_level(item.id, inherited_item_level);
174 // Set access level of nested items.
175 // If it's a mod, also make the visitor walk all of its items
177 ast::ItemKind::Mod(..) => {
178 if access_level.is_some() {
179 self.set_exports_access_level(self.r.local_def_id(item.id));
182 let orig_level = std::mem::replace(&mut self.prev_level, access_level);
183 visit::walk_item(self, item);
184 self.prev_level = orig_level;
187 ast::ItemKind::ForeignMod(ForeignMod { ref items, .. }) => {
188 for nested in items {
189 if nested.vis.kind.is_pub() {
190 self.set_access_level(nested.id, access_level);
194 ast::ItemKind::Enum(EnumDef { ref variants }, _) => {
195 for variant in variants {
196 let variant_level = self.set_access_level(variant.id, access_level);
197 if let Some(ctor_id) = variant.data.ctor_id() {
198 self.set_access_level(ctor_id, access_level);
201 for field in variant.data.fields() {
202 self.set_access_level(field.id, variant_level);
206 ast::ItemKind::Struct(ref def, _) | ast::ItemKind::Union(ref def, _) => {
207 if let Some(ctor_id) = def.ctor_id() {
208 self.set_access_level(ctor_id, access_level);
211 for field in def.fields() {
212 if field.vis.kind.is_pub() {
213 self.set_access_level(field.id, access_level);
217 ast::ItemKind::Trait(ref trait_kind) => {
218 for nested in trait_kind.items.iter() {
219 self.set_access_level(nested.id, access_level);
223 ast::ItemKind::ExternCrate(..)
224 | ast::ItemKind::Use(..)
225 | ast::ItemKind::Static(..)
226 | ast::ItemKind::Const(..)
227 | ast::ItemKind::GlobalAsm(..)
228 | ast::ItemKind::TyAlias(..)
229 | ast::ItemKind::TraitAlias(..)
230 | ast::ItemKind::MacroDef(..)
231 | ast::ItemKind::Fn(..) => return,
234 ast::ItemKind::Impl(..) | ast::ItemKind::MacCall(..) => unreachable!(),