1 #![doc(html_root_url = "https://doc.rust-lang.org/nightly/")]
2 #![feature(in_band_lifetimes)]
4 #![feature(or_patterns)]
5 #![recursion_limit = "256"]
7 use rustc_attr as attr;
8 use rustc_data_structures::fx::FxHashSet;
9 use rustc_errors::struct_span_err;
11 use rustc_hir::def::{DefKind, Res};
12 use rustc_hir::def_id::{CrateNum, DefId, LocalDefId, CRATE_DEF_INDEX, LOCAL_CRATE};
13 use rustc_hir::intravisit::{self, DeepVisitor, NestedVisitorMap, Visitor};
14 use rustc_hir::{AssocItemKind, HirIdSet, Node, PatKind};
15 use rustc_middle::bug;
16 use rustc_middle::hir::map::Map;
17 use rustc_middle::middle::privacy::{AccessLevel, AccessLevels};
18 use rustc_middle::ty::fold::TypeVisitor;
19 use rustc_middle::ty::query::Providers;
20 use rustc_middle::ty::subst::InternalSubsts;
21 use rustc_middle::ty::{self, GenericParamDefKind, TraitRef, Ty, TyCtxt, TypeFoldable};
22 use rustc_session::lint;
23 use rustc_span::hygiene::Transparency;
24 use rustc_span::symbol::{kw, sym, Ident};
27 use std::marker::PhantomData;
28 use std::{cmp, fmt, mem};
30 ////////////////////////////////////////////////////////////////////////////////
31 /// Generic infrastructure used to implement specific visitors below.
32 ////////////////////////////////////////////////////////////////////////////////
34 /// Implemented to visit all `DefId`s in a type.
35 /// Visiting `DefId`s is useful because visibilities and reachabilities are attached to them.
36 /// The idea is to visit "all components of a type", as documented in
37 /// https://github.com/rust-lang/rfcs/blob/master/text/2145-type-privacy.md#how-to-determine-visibility-of-a-type.
38 /// The default type visitor (`TypeVisitor`) does most of the job, but it has some shortcomings.
39 /// First, it doesn't have overridable `fn visit_trait_ref`, so we have to catch trait `DefId`s
40 /// manually. Second, it doesn't visit some type components like signatures of fn types, or traits
41 /// in `impl Trait`, see individual comments in `DefIdVisitorSkeleton::visit_ty`.
42 trait DefIdVisitor<'tcx> {
43 fn tcx(&self) -> TyCtxt<'tcx>;
44 fn shallow(&self) -> bool {
47 fn skip_assoc_tys(&self) -> bool {
50 fn visit_def_id(&mut self, def_id: DefId, kind: &str, descr: &dyn fmt::Display) -> bool;
52 /// Not overridden, but used to actually visit types and traits.
53 fn skeleton(&mut self) -> DefIdVisitorSkeleton<'_, 'tcx, Self> {
54 DefIdVisitorSkeleton {
56 visited_opaque_tys: Default::default(),
57 dummy: Default::default(),
60 fn visit(&mut self, ty_fragment: impl TypeFoldable<'tcx>) -> bool {
61 ty_fragment.visit_with(&mut self.skeleton())
63 fn visit_trait(&mut self, trait_ref: TraitRef<'tcx>) -> bool {
64 self.skeleton().visit_trait(trait_ref)
66 fn visit_predicates(&mut self, predicates: ty::GenericPredicates<'tcx>) -> bool {
67 self.skeleton().visit_predicates(predicates)
71 struct DefIdVisitorSkeleton<'v, 'tcx, V: ?Sized> {
72 def_id_visitor: &'v mut V,
73 visited_opaque_tys: FxHashSet<DefId>,
74 dummy: PhantomData<TyCtxt<'tcx>>,
77 impl<'tcx, V> DefIdVisitorSkeleton<'_, 'tcx, V>
79 V: DefIdVisitor<'tcx> + ?Sized,
81 fn visit_trait(&mut self, trait_ref: TraitRef<'tcx>) -> bool {
82 let TraitRef { def_id, substs } = trait_ref;
83 self.def_id_visitor.visit_def_id(def_id, "trait", &trait_ref.print_only_trait_path())
84 || (!self.def_id_visitor.shallow() && substs.visit_with(self))
87 fn visit_predicate(&mut self, predicate: ty::Predicate<'tcx>) -> bool {
88 match predicate.skip_binders() {
89 ty::PredicateAtom::Trait(ty::TraitPredicate { trait_ref }, _) => {
90 self.visit_trait(trait_ref)
92 ty::PredicateAtom::Projection(ty::ProjectionPredicate { projection_ty, ty }) => {
94 || self.visit_trait(projection_ty.trait_ref(self.def_id_visitor.tcx()))
96 ty::PredicateAtom::TypeOutlives(ty::OutlivesPredicate(ty, _region)) => {
99 ty::PredicateAtom::RegionOutlives(..) => false,
100 ty::PredicateAtom::ConstEvaluatable(..)
101 if self.def_id_visitor.tcx().features().const_evaluatable_checked =>
103 // FIXME(const_evaluatable_checked): If the constant used here depends on a
104 // private function we may have to do something here...
106 // For now, let's just pretend that everything is fine.
109 _ => bug!("unexpected predicate: {:?}", predicate),
113 fn visit_predicates(&mut self, predicates: ty::GenericPredicates<'tcx>) -> bool {
114 let ty::GenericPredicates { parent: _, predicates } = predicates;
115 for &(predicate, _span) in predicates {
116 if self.visit_predicate(predicate) {
124 impl<'tcx, V> TypeVisitor<'tcx> for DefIdVisitorSkeleton<'_, 'tcx, V>
126 V: DefIdVisitor<'tcx> + ?Sized,
128 fn visit_ty(&mut self, ty: Ty<'tcx>) -> bool {
129 let tcx = self.def_id_visitor.tcx();
130 // InternalSubsts are not visited here because they are visited below in `super_visit_with`.
132 ty::Adt(&ty::AdtDef { did: def_id, .. }, ..)
133 | ty::Foreign(def_id)
134 | ty::FnDef(def_id, ..)
135 | ty::Closure(def_id, ..)
136 | ty::Generator(def_id, ..) => {
137 if self.def_id_visitor.visit_def_id(def_id, "type", &ty) {
140 if self.def_id_visitor.shallow() {
143 // Default type visitor doesn't visit signatures of fn types.
144 // Something like `fn() -> Priv {my_func}` is considered a private type even if
145 // `my_func` is public, so we need to visit signatures.
146 if let ty::FnDef(..) = ty.kind() {
147 if tcx.fn_sig(def_id).visit_with(self) {
151 // Inherent static methods don't have self type in substs.
152 // Something like `fn() {my_method}` type of the method
153 // `impl Pub<Priv> { pub fn my_method() {} }` is considered a private type,
154 // so we need to visit the self type additionally.
155 if let Some(assoc_item) = tcx.opt_associated_item(def_id) {
156 if let ty::ImplContainer(impl_def_id) = assoc_item.container {
157 if tcx.type_of(impl_def_id).visit_with(self) {
163 ty::Projection(proj) => {
164 if self.def_id_visitor.skip_assoc_tys() {
165 // Visitors searching for minimal visibility/reachability want to
166 // conservatively approximate associated types like `<Type as Trait>::Alias`
167 // as visible/reachable even if both `Type` and `Trait` are private.
168 // Ideally, associated types should be substituted in the same way as
169 // free type aliases, but this isn't done yet.
172 // This will also visit substs if necessary, so we don't need to recurse.
173 return self.visit_trait(proj.trait_ref(tcx));
175 ty::Dynamic(predicates, ..) => {
176 // All traits in the list are considered the "primary" part of the type
177 // and are visited by shallow visitors.
178 for predicate in predicates.skip_binder() {
179 let trait_ref = match predicate {
180 ty::ExistentialPredicate::Trait(trait_ref) => trait_ref,
181 ty::ExistentialPredicate::Projection(proj) => proj.trait_ref(tcx),
182 ty::ExistentialPredicate::AutoTrait(def_id) => {
183 ty::ExistentialTraitRef { def_id, substs: InternalSubsts::empty() }
186 let ty::ExistentialTraitRef { def_id, substs: _ } = trait_ref;
187 if self.def_id_visitor.visit_def_id(def_id, "trait", &trait_ref) {
192 ty::Opaque(def_id, ..) => {
193 // Skip repeated `Opaque`s to avoid infinite recursion.
194 if self.visited_opaque_tys.insert(def_id) {
195 // The intent is to treat `impl Trait1 + Trait2` identically to
196 // `dyn Trait1 + Trait2`. Therefore we ignore def-id of the opaque type itself
197 // (it either has no visibility, or its visibility is insignificant, like
198 // visibilities of type aliases) and recurse into predicates instead to go
199 // through the trait list (default type visitor doesn't visit those traits).
200 // All traits in the list are considered the "primary" part of the type
201 // and are visited by shallow visitors.
202 if self.visit_predicates(tcx.predicates_of(def_id)) {
207 // These types don't have their own def-ids (but may have subcomponents
208 // with def-ids that should be visited recursively).
224 | ty::GeneratorWitness(..) => {}
225 ty::Bound(..) | ty::Placeholder(..) | ty::Infer(..) => {
226 bug!("unexpected type: {:?}", ty)
230 !self.def_id_visitor.shallow() && ty.super_visit_with(self)
234 fn def_id_visibility<'tcx>(
237 ) -> (ty::Visibility, Span, &'static str) {
238 match def_id.as_local().map(|def_id| tcx.hir().local_def_id_to_hir_id(def_id)) {
240 let vis = match tcx.hir().get(hir_id) {
241 Node::Item(item) => &item.vis,
242 Node::ForeignItem(foreign_item) => &foreign_item.vis,
243 Node::MacroDef(macro_def) => {
244 if tcx.sess.contains_name(¯o_def.attrs, sym::macro_export) {
245 return (ty::Visibility::Public, macro_def.span, "public");
250 Node::TraitItem(..) | Node::Variant(..) => {
251 return def_id_visibility(tcx, tcx.hir().get_parent_did(hir_id).to_def_id());
253 Node::ImplItem(impl_item) => {
254 match tcx.hir().get(tcx.hir().get_parent_item(hir_id)) {
255 Node::Item(item) => match &item.kind {
256 hir::ItemKind::Impl { of_trait: None, .. } => &impl_item.vis,
257 hir::ItemKind::Impl { of_trait: Some(trait_ref), .. } => {
258 return def_id_visibility(tcx, trait_ref.path.res.def_id());
260 kind => bug!("unexpected item kind: {:?}", kind),
262 node => bug!("unexpected node kind: {:?}", node),
265 Node::Ctor(vdata) => {
266 let parent_hir_id = tcx.hir().get_parent_node(hir_id);
267 match tcx.hir().get(parent_hir_id) {
268 Node::Variant(..) => {
269 let parent_did = tcx.hir().local_def_id(parent_hir_id);
270 let (mut ctor_vis, mut span, mut descr) =
271 def_id_visibility(tcx, parent_did.to_def_id());
273 let adt_def = tcx.adt_def(tcx.hir().get_parent_did(hir_id).to_def_id());
274 let ctor_did = tcx.hir().local_def_id(vdata.ctor_hir_id().unwrap());
275 let variant = adt_def.variant_with_ctor_id(ctor_did.to_def_id());
277 if variant.is_field_list_non_exhaustive()
278 && ctor_vis == ty::Visibility::Public
281 ty::Visibility::Restricted(DefId::local(CRATE_DEF_INDEX));
282 let attrs = tcx.get_attrs(variant.def_id);
285 .find_by_name(&attrs, sym::non_exhaustive)
288 descr = "crate-visible";
291 return (ctor_vis, span, descr);
294 let item = match tcx.hir().get(parent_hir_id) {
295 Node::Item(item) => item,
296 node => bug!("unexpected node kind: {:?}", node),
298 let (mut ctor_vis, mut span, mut descr) = (
299 ty::Visibility::from_hir(&item.vis, parent_hir_id, tcx),
301 item.vis.node.descr(),
303 for field in vdata.fields() {
304 let field_vis = ty::Visibility::from_hir(&field.vis, hir_id, tcx);
305 if ctor_vis.is_at_least(field_vis, tcx) {
306 ctor_vis = field_vis;
307 span = field.vis.span;
308 descr = field.vis.node.descr();
312 // If the structure is marked as non_exhaustive then lower the
313 // visibility to within the crate.
314 if ctor_vis == ty::Visibility::Public {
316 tcx.adt_def(tcx.hir().get_parent_did(hir_id).to_def_id());
317 if adt_def.non_enum_variant().is_field_list_non_exhaustive() {
319 ty::Visibility::Restricted(DefId::local(CRATE_DEF_INDEX));
322 .find_by_name(&item.attrs, sym::non_exhaustive)
325 descr = "crate-visible";
329 return (ctor_vis, span, descr);
331 node => bug!("unexpected node kind: {:?}", node),
334 Node::Expr(expr) => {
336 ty::Visibility::Restricted(tcx.parent_module(expr.hir_id).to_def_id()),
341 node => bug!("unexpected node kind: {:?}", node),
343 (ty::Visibility::from_hir(vis, hir_id, tcx), vis.span, vis.node.descr())
346 let vis = tcx.visibility(def_id);
347 let descr = if vis == ty::Visibility::Public { "public" } else { "private" };
348 (vis, tcx.def_span(def_id), descr)
353 fn min(vis1: ty::Visibility, vis2: ty::Visibility, tcx: TyCtxt<'_>) -> ty::Visibility {
354 if vis1.is_at_least(vis2, tcx) { vis2 } else { vis1 }
357 ////////////////////////////////////////////////////////////////////////////////
358 /// Visitor used to determine if pub(restricted) is used anywhere in the crate.
360 /// This is done so that `private_in_public` warnings can be turned into hard errors
361 /// in crates that have been updated to use pub(restricted).
362 ////////////////////////////////////////////////////////////////////////////////
363 struct PubRestrictedVisitor<'tcx> {
365 has_pub_restricted: bool,
368 impl Visitor<'tcx> for PubRestrictedVisitor<'tcx> {
369 type Map = Map<'tcx>;
371 fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
372 NestedVisitorMap::All(self.tcx.hir())
374 fn visit_vis(&mut self, vis: &'tcx hir::Visibility<'tcx>) {
375 self.has_pub_restricted = self.has_pub_restricted || vis.node.is_pub_restricted();
379 ////////////////////////////////////////////////////////////////////////////////
380 /// Visitor used to determine impl visibility and reachability.
381 ////////////////////////////////////////////////////////////////////////////////
383 struct FindMin<'a, 'tcx, VL: VisibilityLike> {
385 access_levels: &'a AccessLevels,
389 impl<'a, 'tcx, VL: VisibilityLike> DefIdVisitor<'tcx> for FindMin<'a, 'tcx, VL> {
390 fn tcx(&self) -> TyCtxt<'tcx> {
393 fn shallow(&self) -> bool {
396 fn skip_assoc_tys(&self) -> bool {
399 fn visit_def_id(&mut self, def_id: DefId, _kind: &str, _descr: &dyn fmt::Display) -> bool {
400 self.min = VL::new_min(self, def_id);
405 trait VisibilityLike: Sized {
407 const SHALLOW: bool = false;
408 fn new_min(find: &FindMin<'_, '_, Self>, def_id: DefId) -> Self;
410 // Returns an over-approximation (`skip_assoc_tys` = true) of visibility due to
411 // associated types for which we can't determine visibility precisely.
412 fn of_impl(hir_id: hir::HirId, tcx: TyCtxt<'_>, access_levels: &AccessLevels) -> Self {
413 let mut find = FindMin { tcx, access_levels, min: Self::MAX };
414 let def_id = tcx.hir().local_def_id(hir_id);
415 find.visit(tcx.type_of(def_id));
416 if let Some(trait_ref) = tcx.impl_trait_ref(def_id) {
417 find.visit_trait(trait_ref);
422 impl VisibilityLike for ty::Visibility {
423 const MAX: Self = ty::Visibility::Public;
424 fn new_min(find: &FindMin<'_, '_, Self>, def_id: DefId) -> Self {
425 min(def_id_visibility(find.tcx, def_id).0, find.min, find.tcx)
428 impl VisibilityLike for Option<AccessLevel> {
429 const MAX: Self = Some(AccessLevel::Public);
430 // Type inference is very smart sometimes.
431 // It can make an impl reachable even some components of its type or trait are unreachable.
432 // E.g. methods of `impl ReachableTrait<UnreachableTy> for ReachableTy<UnreachableTy> { ... }`
433 // can be usable from other crates (#57264). So we skip substs when calculating reachability
434 // and consider an impl reachable if its "shallow" type and trait are reachable.
436 // The assumption we make here is that type-inference won't let you use an impl without knowing
437 // both "shallow" version of its self type and "shallow" version of its trait if it exists
438 // (which require reaching the `DefId`s in them).
439 const SHALLOW: bool = true;
440 fn new_min(find: &FindMin<'_, '_, Self>, def_id: DefId) -> Self {
442 if let Some(def_id) = def_id.as_local() {
443 let hir_id = find.tcx.hir().local_def_id_to_hir_id(def_id);
444 find.access_levels.map.get(&hir_id).cloned()
453 ////////////////////////////////////////////////////////////////////////////////
454 /// The embargo visitor, used to determine the exports of the AST.
455 ////////////////////////////////////////////////////////////////////////////////
457 struct EmbargoVisitor<'tcx> {
460 /// Accessibility levels for reachable nodes.
461 access_levels: AccessLevels,
462 /// A set of pairs corresponding to modules, where the first module is
463 /// reachable via a macro that's defined in the second module. This cannot
464 /// be represented as reachable because it can't handle the following case:
466 /// pub mod n { // Should be `Public`
467 /// pub(crate) mod p { // Should *not* be accessible
468 /// pub fn f() -> i32 { 12 } // Must be `Reachable`
474 macro_reachable: FxHashSet<(hir::HirId, DefId)>,
475 /// Previous accessibility level; `None` means unreachable.
476 prev_level: Option<AccessLevel>,
477 /// Has something changed in the level map?
481 struct ReachEverythingInTheInterfaceVisitor<'a, 'tcx> {
482 access_level: Option<AccessLevel>,
484 ev: &'a mut EmbargoVisitor<'tcx>,
487 impl EmbargoVisitor<'tcx> {
488 fn get(&self, id: hir::HirId) -> Option<AccessLevel> {
489 self.access_levels.map.get(&id).cloned()
492 /// Updates node level and returns the updated level.
493 fn update(&mut self, id: hir::HirId, level: Option<AccessLevel>) -> Option<AccessLevel> {
494 let old_level = self.get(id);
495 // Accessibility levels can only grow.
496 if level > old_level {
497 self.access_levels.map.insert(id, level.unwrap());
508 access_level: Option<AccessLevel>,
509 ) -> ReachEverythingInTheInterfaceVisitor<'_, 'tcx> {
510 ReachEverythingInTheInterfaceVisitor {
511 access_level: cmp::min(access_level, Some(AccessLevel::Reachable)),
512 item_def_id: self.tcx.hir().local_def_id(item_id).to_def_id(),
517 /// Updates the item as being reachable through a macro defined in the given
518 /// module. Returns `true` if the level has changed.
519 fn update_macro_reachable(&mut self, reachable_mod: hir::HirId, defining_mod: DefId) -> bool {
520 if self.macro_reachable.insert((reachable_mod, defining_mod)) {
521 self.update_macro_reachable_mod(reachable_mod, defining_mod);
528 fn update_macro_reachable_mod(&mut self, reachable_mod: hir::HirId, defining_mod: DefId) {
529 let module_def_id = self.tcx.hir().local_def_id(reachable_mod);
530 let module = self.tcx.hir().get_module(module_def_id).0;
531 for item_id in module.item_ids {
532 let hir_id = item_id.id;
533 let item_def_id = self.tcx.hir().local_def_id(hir_id);
534 let def_kind = self.tcx.def_kind(item_def_id);
535 let item = self.tcx.hir().expect_item(hir_id);
536 let vis = ty::Visibility::from_hir(&item.vis, hir_id, self.tcx);
537 self.update_macro_reachable_def(hir_id, def_kind, vis, defining_mod);
539 if let Some(exports) = self.tcx.module_exports(module_def_id) {
540 for export in exports {
541 if export.vis.is_accessible_from(defining_mod, self.tcx) {
542 if let Res::Def(def_kind, def_id) = export.res {
543 let vis = def_id_visibility(self.tcx, def_id).0;
544 if let Some(def_id) = def_id.as_local() {
545 let hir_id = self.tcx.hir().local_def_id_to_hir_id(def_id);
546 self.update_macro_reachable_def(hir_id, def_kind, vis, defining_mod);
554 fn update_macro_reachable_def(
561 let level = Some(AccessLevel::Reachable);
562 if let ty::Visibility::Public = vis {
563 self.update(hir_id, level);
566 // No type privacy, so can be directly marked as reachable.
570 | DefKind::TraitAlias
571 | DefKind::TyAlias => {
572 if vis.is_accessible_from(module, self.tcx) {
573 self.update(hir_id, level);
577 // We can't use a module name as the final segment of a path, except
578 // in use statements. Since re-export checking doesn't consider
579 // hygiene these don't need to be marked reachable. The contents of
580 // the module, however may be reachable.
582 if vis.is_accessible_from(module, self.tcx) {
583 self.update_macro_reachable(hir_id, module);
587 DefKind::Struct | DefKind::Union => {
588 // While structs and unions have type privacy, their fields do
590 if let ty::Visibility::Public = vis {
591 let item = self.tcx.hir().expect_item(hir_id);
592 if let hir::ItemKind::Struct(ref struct_def, _)
593 | hir::ItemKind::Union(ref struct_def, _) = item.kind
595 for field in struct_def.fields() {
597 ty::Visibility::from_hir(&field.vis, field.hir_id, self.tcx);
598 if field_vis.is_accessible_from(module, self.tcx) {
599 self.reach(field.hir_id, level).ty();
603 bug!("item {:?} with DefKind {:?}", item, def_kind);
608 // These have type privacy, so are not reachable unless they're
609 // public, or are not namespaced at all.
612 | DefKind::ConstParam
613 | DefKind::Ctor(_, _)
622 | DefKind::LifetimeParam
623 | DefKind::ExternCrate
625 | DefKind::ForeignMod
631 | DefKind::Generator => (),
635 /// Given the path segments of a `ItemKind::Use`, then we need
636 /// to update the visibility of the intermediate use so that it isn't linted
637 /// by `unreachable_pub`.
639 /// This isn't trivial as `path.res` has the `DefId` of the eventual target
640 /// of the use statement not of the next intermediate use statement.
642 /// To do this, consider the last two segments of the path to our intermediate
643 /// use statement. We expect the penultimate segment to be a module and the
644 /// last segment to be the name of the item we are exporting. We can then
645 /// look at the items contained in the module for the use statement with that
646 /// name and update that item's visibility.
648 /// FIXME: This solution won't work with glob imports and doesn't respect
649 /// namespaces. See <https://github.com/rust-lang/rust/pull/57922#discussion_r251234202>.
650 fn update_visibility_of_intermediate_use_statements(
652 segments: &[hir::PathSegment<'_>],
654 if let [.., module, segment] = segments {
655 if let Some(item) = module
657 .and_then(|res| res.mod_def_id())
658 // If the module is `self`, i.e. the current crate,
659 // there will be no corresponding item.
660 .filter(|def_id| def_id.index != CRATE_DEF_INDEX || def_id.krate != LOCAL_CRATE)
662 def_id.as_local().map(|def_id| self.tcx.hir().local_def_id_to_hir_id(def_id))
664 .map(|module_hir_id| self.tcx.hir().expect_item(module_hir_id))
666 if let hir::ItemKind::Mod(m) = &item.kind {
667 for item_id in m.item_ids {
668 let item = self.tcx.hir().expect_item(item_id.id);
669 let def_id = self.tcx.hir().local_def_id(item_id.id);
670 if !self.tcx.hygienic_eq(segment.ident, item.ident, def_id.to_def_id()) {
673 if let hir::ItemKind::Use(..) = item.kind {
674 self.update(item.hir_id, Some(AccessLevel::Exported));
683 impl Visitor<'tcx> for EmbargoVisitor<'tcx> {
684 type Map = Map<'tcx>;
686 /// We want to visit items in the context of their containing
687 /// module and so forth, so supply a crate for doing a deep walk.
688 fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
689 NestedVisitorMap::All(self.tcx.hir())
692 fn visit_item(&mut self, item: &'tcx hir::Item<'tcx>) {
693 let inherited_item_level = match item.kind {
694 hir::ItemKind::Impl { .. } => {
695 Option::<AccessLevel>::of_impl(item.hir_id, self.tcx, &self.access_levels)
697 // Foreign modules inherit level from parents.
698 hir::ItemKind::ForeignMod(..) => self.prev_level,
699 // Other `pub` items inherit levels from parents.
700 hir::ItemKind::Const(..)
701 | hir::ItemKind::Enum(..)
702 | hir::ItemKind::ExternCrate(..)
703 | hir::ItemKind::GlobalAsm(..)
704 | hir::ItemKind::Fn(..)
705 | hir::ItemKind::Mod(..)
706 | hir::ItemKind::Static(..)
707 | hir::ItemKind::Struct(..)
708 | hir::ItemKind::Trait(..)
709 | hir::ItemKind::TraitAlias(..)
710 | hir::ItemKind::OpaqueTy(..)
711 | hir::ItemKind::TyAlias(..)
712 | hir::ItemKind::Union(..)
713 | hir::ItemKind::Use(..) => {
714 if item.vis.node.is_pub() {
722 // Update level of the item itself.
723 let item_level = self.update(item.hir_id, inherited_item_level);
725 // Update levels of nested things.
727 hir::ItemKind::Enum(ref def, _) => {
728 for variant in def.variants {
729 let variant_level = self.update(variant.id, item_level);
730 if let Some(ctor_hir_id) = variant.data.ctor_hir_id() {
731 self.update(ctor_hir_id, item_level);
733 for field in variant.data.fields() {
734 self.update(field.hir_id, variant_level);
738 hir::ItemKind::Impl { ref of_trait, items, .. } => {
739 for impl_item_ref in items {
740 if of_trait.is_some() || impl_item_ref.vis.node.is_pub() {
741 self.update(impl_item_ref.id.hir_id, item_level);
745 hir::ItemKind::Trait(.., trait_item_refs) => {
746 for trait_item_ref in trait_item_refs {
747 self.update(trait_item_ref.id.hir_id, item_level);
750 hir::ItemKind::Struct(ref def, _) | hir::ItemKind::Union(ref def, _) => {
751 if let Some(ctor_hir_id) = def.ctor_hir_id() {
752 self.update(ctor_hir_id, item_level);
754 for field in def.fields() {
755 if field.vis.node.is_pub() {
756 self.update(field.hir_id, item_level);
760 hir::ItemKind::ForeignMod(ref foreign_mod) => {
761 for foreign_item in foreign_mod.items {
762 if foreign_item.vis.node.is_pub() {
763 self.update(foreign_item.hir_id, item_level);
767 hir::ItemKind::OpaqueTy(..)
768 | hir::ItemKind::Use(..)
769 | hir::ItemKind::Static(..)
770 | hir::ItemKind::Const(..)
771 | hir::ItemKind::GlobalAsm(..)
772 | hir::ItemKind::TyAlias(..)
773 | hir::ItemKind::Mod(..)
774 | hir::ItemKind::TraitAlias(..)
775 | hir::ItemKind::Fn(..)
776 | hir::ItemKind::ExternCrate(..) => {}
779 // Mark all items in interfaces of reachable items as reachable.
781 // The interface is empty.
782 hir::ItemKind::ExternCrate(..) => {}
783 // All nested items are checked by `visit_item`.
784 hir::ItemKind::Mod(..) => {}
785 // Re-exports are handled in `visit_mod`. However, in order to avoid looping over
786 // all of the items of a mod in `visit_mod` looking for use statements, we handle
787 // making sure that intermediate use statements have their visibilities updated here.
788 hir::ItemKind::Use(ref path, _) => {
789 if item_level.is_some() {
790 self.update_visibility_of_intermediate_use_statements(path.segments.as_ref());
793 // The interface is empty.
794 hir::ItemKind::GlobalAsm(..) => {}
795 hir::ItemKind::OpaqueTy(..) => {
796 // HACK(jynelson): trying to infer the type of `impl trait` breaks `async-std` (and `pub async fn` in general)
797 // Since rustdoc never need to do codegen and doesn't care about link-time reachability,
798 // mark this as unreachable.
799 // See https://github.com/rust-lang/rust/issues/75100
800 if !self.tcx.sess.opts.actually_rustdoc {
801 // FIXME: This is some serious pessimization intended to workaround deficiencies
802 // in the reachability pass (`middle/reachable.rs`). Types are marked as link-time
803 // reachable if they are returned via `impl Trait`, even from private functions.
805 cmp::max(item_level, Some(AccessLevel::ReachableFromImplTrait));
806 self.reach(item.hir_id, exist_level).generics().predicates().ty();
810 hir::ItemKind::Const(..)
811 | hir::ItemKind::Static(..)
812 | hir::ItemKind::Fn(..)
813 | hir::ItemKind::TyAlias(..) => {
814 if item_level.is_some() {
815 self.reach(item.hir_id, item_level).generics().predicates().ty();
818 hir::ItemKind::Trait(.., trait_item_refs) => {
819 if item_level.is_some() {
820 self.reach(item.hir_id, item_level).generics().predicates();
822 for trait_item_ref in trait_item_refs {
823 let mut reach = self.reach(trait_item_ref.id.hir_id, item_level);
824 reach.generics().predicates();
826 if trait_item_ref.kind == AssocItemKind::Type
827 && !trait_item_ref.defaultness.has_value()
836 hir::ItemKind::TraitAlias(..) => {
837 if item_level.is_some() {
838 self.reach(item.hir_id, item_level).generics().predicates();
841 // Visit everything except for private impl items.
842 hir::ItemKind::Impl { items, .. } => {
843 if item_level.is_some() {
844 self.reach(item.hir_id, item_level).generics().predicates().ty().trait_ref();
846 for impl_item_ref in items {
847 let impl_item_level = self.get(impl_item_ref.id.hir_id);
848 if impl_item_level.is_some() {
849 self.reach(impl_item_ref.id.hir_id, impl_item_level)
858 // Visit everything, but enum variants have their own levels.
859 hir::ItemKind::Enum(ref def, _) => {
860 if item_level.is_some() {
861 self.reach(item.hir_id, item_level).generics().predicates();
863 for variant in def.variants {
864 let variant_level = self.get(variant.id);
865 if variant_level.is_some() {
866 for field in variant.data.fields() {
867 self.reach(field.hir_id, variant_level).ty();
869 // Corner case: if the variant is reachable, but its
870 // enum is not, make the enum reachable as well.
871 self.update(item.hir_id, variant_level);
875 // Visit everything, but foreign items have their own levels.
876 hir::ItemKind::ForeignMod(ref foreign_mod) => {
877 for foreign_item in foreign_mod.items {
878 let foreign_item_level = self.get(foreign_item.hir_id);
879 if foreign_item_level.is_some() {
880 self.reach(foreign_item.hir_id, foreign_item_level)
887 // Visit everything except for private fields.
888 hir::ItemKind::Struct(ref struct_def, _) | hir::ItemKind::Union(ref struct_def, _) => {
889 if item_level.is_some() {
890 self.reach(item.hir_id, item_level).generics().predicates();
891 for field in struct_def.fields() {
892 let field_level = self.get(field.hir_id);
893 if field_level.is_some() {
894 self.reach(field.hir_id, field_level).ty();
901 let orig_level = mem::replace(&mut self.prev_level, item_level);
902 intravisit::walk_item(self, item);
903 self.prev_level = orig_level;
906 fn visit_block(&mut self, b: &'tcx hir::Block<'tcx>) {
907 // Blocks can have public items, for example impls, but they always
908 // start as completely private regardless of publicity of a function,
909 // constant, type, field, etc., in which this block resides.
910 let orig_level = mem::replace(&mut self.prev_level, None);
911 intravisit::walk_block(self, b);
912 self.prev_level = orig_level;
915 fn visit_mod(&mut self, m: &'tcx hir::Mod<'tcx>, _sp: Span, id: hir::HirId) {
916 // This code is here instead of in visit_item so that the
917 // crate module gets processed as well.
918 if self.prev_level.is_some() {
919 let def_id = self.tcx.hir().local_def_id(id);
920 if let Some(exports) = self.tcx.module_exports(def_id) {
921 for export in exports.iter() {
922 if export.vis == ty::Visibility::Public {
923 if let Some(def_id) = export.res.opt_def_id() {
924 if let Some(def_id) = def_id.as_local() {
925 let hir_id = self.tcx.hir().local_def_id_to_hir_id(def_id);
926 self.update(hir_id, Some(AccessLevel::Exported));
934 intravisit::walk_mod(self, m, id);
937 fn visit_macro_def(&mut self, md: &'tcx hir::MacroDef<'tcx>) {
938 if attr::find_transparency(&self.tcx.sess, &md.attrs, md.ast.macro_rules).0
939 != Transparency::Opaque
941 self.update(md.hir_id, Some(AccessLevel::Public));
945 let macro_module_def_id =
946 ty::DefIdTree::parent(self.tcx, self.tcx.hir().local_def_id(md.hir_id).to_def_id())
948 // FIXME(#71104) Should really be using just `as_local_hir_id` but
949 // some `DefId` do not seem to have a corresponding HirId.
950 let hir_id = macro_module_def_id
952 .and_then(|def_id| self.tcx.hir().opt_local_def_id_to_hir_id(def_id));
953 let mut module_id = match hir_id {
954 Some(module_id) if self.tcx.hir().is_hir_id_module(module_id) => module_id,
955 // `module_id` doesn't correspond to a `mod`, return early (#63164, #65252).
958 let level = if md.vis.node.is_pub() { self.get(module_id) } else { None };
959 let new_level = self.update(md.hir_id, level);
960 if new_level.is_none() {
965 let changed_reachability = self.update_macro_reachable(module_id, macro_module_def_id);
966 if changed_reachability || module_id == hir::CRATE_HIR_ID {
969 module_id = self.tcx.hir().get_parent_node(module_id);
974 impl ReachEverythingInTheInterfaceVisitor<'_, 'tcx> {
975 fn generics(&mut self) -> &mut Self {
976 for param in &self.ev.tcx.generics_of(self.item_def_id).params {
978 GenericParamDefKind::Lifetime => {}
979 GenericParamDefKind::Type { has_default, .. } => {
981 self.visit(self.ev.tcx.type_of(param.def_id));
984 GenericParamDefKind::Const => {
985 self.visit(self.ev.tcx.type_of(param.def_id));
992 fn predicates(&mut self) -> &mut Self {
993 self.visit_predicates(self.ev.tcx.predicates_of(self.item_def_id));
997 fn ty(&mut self) -> &mut Self {
998 self.visit(self.ev.tcx.type_of(self.item_def_id));
1002 fn trait_ref(&mut self) -> &mut Self {
1003 if let Some(trait_ref) = self.ev.tcx.impl_trait_ref(self.item_def_id) {
1004 self.visit_trait(trait_ref);
1010 impl DefIdVisitor<'tcx> for ReachEverythingInTheInterfaceVisitor<'_, 'tcx> {
1011 fn tcx(&self) -> TyCtxt<'tcx> {
1014 fn visit_def_id(&mut self, def_id: DefId, _kind: &str, _descr: &dyn fmt::Display) -> bool {
1015 if let Some(def_id) = def_id.as_local() {
1016 let hir_id = self.ev.tcx.hir().local_def_id_to_hir_id(def_id);
1017 if let ((ty::Visibility::Public, ..), _)
1018 | (_, Some(AccessLevel::ReachableFromImplTrait)) =
1019 (def_id_visibility(self.tcx(), def_id.to_def_id()), self.access_level)
1021 self.ev.update(hir_id, self.access_level);
1028 //////////////////////////////////////////////////////////////////////////////////////
1029 /// Name privacy visitor, checks privacy and reports violations.
1030 /// Most of name privacy checks are performed during the main resolution phase,
1031 /// or later in type checking when field accesses and associated items are resolved.
1032 /// This pass performs remaining checks for fields in struct expressions and patterns.
1033 //////////////////////////////////////////////////////////////////////////////////////
1035 struct NamePrivacyVisitor<'tcx> {
1037 maybe_typeck_results: Option<&'tcx ty::TypeckResults<'tcx>>,
1038 current_item: Option<hir::HirId>,
1041 impl<'tcx> NamePrivacyVisitor<'tcx> {
1042 /// Gets the type-checking results for the current body.
1043 /// As this will ICE if called outside bodies, only call when working with
1044 /// `Expr` or `Pat` nodes (they are guaranteed to be found only in bodies).
1046 fn typeck_results(&self) -> &'tcx ty::TypeckResults<'tcx> {
1047 self.maybe_typeck_results
1048 .expect("`NamePrivacyVisitor::typeck_results` called outside of body")
1051 // Checks that a field in a struct constructor (expression or pattern) is accessible.
1054 use_ctxt: Span, // syntax context of the field name at the use site
1055 span: Span, // span of the field pattern, e.g., `x: 0`
1056 def: &'tcx ty::AdtDef, // definition of the struct or enum
1057 field: &'tcx ty::FieldDef,
1058 in_update_syntax: bool,
1060 // definition of the field
1061 let ident = Ident::new(kw::Invalid, use_ctxt);
1062 let current_hir = self.current_item.unwrap();
1063 let def_id = self.tcx.adjust_ident_and_get_scope(ident, def.did, current_hir).1;
1064 if !def.is_enum() && !field.vis.is_accessible_from(def_id, self.tcx) {
1065 let label = if in_update_syntax {
1066 format!("field `{}` is private", field.ident)
1068 "private field".to_string()
1075 "field `{}` of {} `{}` is private",
1077 def.variant_descr(),
1078 self.tcx.def_path_str(def.did)
1080 .span_label(span, label)
1086 impl<'tcx> Visitor<'tcx> for NamePrivacyVisitor<'tcx> {
1087 type Map = Map<'tcx>;
1089 /// We want to visit items in the context of their containing
1090 /// module and so forth, so supply a crate for doing a deep walk.
1091 fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
1092 NestedVisitorMap::All(self.tcx.hir())
1095 fn visit_mod(&mut self, _m: &'tcx hir::Mod<'tcx>, _s: Span, _n: hir::HirId) {
1096 // Don't visit nested modules, since we run a separate visitor walk
1097 // for each module in `privacy_access_levels`
1100 fn visit_nested_body(&mut self, body: hir::BodyId) {
1101 let old_maybe_typeck_results =
1102 self.maybe_typeck_results.replace(self.tcx.typeck_body(body));
1103 let body = self.tcx.hir().body(body);
1104 self.visit_body(body);
1105 self.maybe_typeck_results = old_maybe_typeck_results;
1108 fn visit_item(&mut self, item: &'tcx hir::Item<'tcx>) {
1109 let orig_current_item = self.current_item.replace(item.hir_id);
1110 intravisit::walk_item(self, item);
1111 self.current_item = orig_current_item;
1114 fn visit_expr(&mut self, expr: &'tcx hir::Expr<'tcx>) {
1115 if let hir::ExprKind::Struct(ref qpath, fields, ref base) = expr.kind {
1116 let res = self.typeck_results().qpath_res(qpath, expr.hir_id);
1117 let adt = self.typeck_results().expr_ty(expr).ty_adt_def().unwrap();
1118 let variant = adt.variant_of_res(res);
1119 if let Some(ref base) = *base {
1120 // If the expression uses FRU we need to make sure all the unmentioned fields
1121 // are checked for privacy (RFC 736). Rather than computing the set of
1122 // unmentioned fields, just check them all.
1123 for (vf_index, variant_field) in variant.fields.iter().enumerate() {
1124 let field = fields.iter().find(|f| {
1125 self.tcx.field_index(f.hir_id, self.typeck_results()) == vf_index
1127 let (use_ctxt, span) = match field {
1128 Some(field) => (field.ident.span, field.span),
1129 None => (base.span, base.span),
1131 self.check_field(use_ctxt, span, adt, variant_field, true);
1134 for field in fields {
1135 let use_ctxt = field.ident.span;
1136 let index = self.tcx.field_index(field.hir_id, self.typeck_results());
1137 self.check_field(use_ctxt, field.span, adt, &variant.fields[index], false);
1142 intravisit::walk_expr(self, expr);
1145 fn visit_pat(&mut self, pat: &'tcx hir::Pat<'tcx>) {
1146 if let PatKind::Struct(ref qpath, fields, _) = pat.kind {
1147 let res = self.typeck_results().qpath_res(qpath, pat.hir_id);
1148 let adt = self.typeck_results().pat_ty(pat).ty_adt_def().unwrap();
1149 let variant = adt.variant_of_res(res);
1150 for field in fields {
1151 let use_ctxt = field.ident.span;
1152 let index = self.tcx.field_index(field.hir_id, self.typeck_results());
1153 self.check_field(use_ctxt, field.span, adt, &variant.fields[index], false);
1157 intravisit::walk_pat(self, pat);
1161 ////////////////////////////////////////////////////////////////////////////////////////////
1162 /// Type privacy visitor, checks types for privacy and reports violations.
1163 /// Both explicitly written types and inferred types of expressions and patters are checked.
1164 /// Checks are performed on "semantic" types regardless of names and their hygiene.
1165 ////////////////////////////////////////////////////////////////////////////////////////////
1167 struct TypePrivacyVisitor<'tcx> {
1169 maybe_typeck_results: Option<&'tcx ty::TypeckResults<'tcx>>,
1170 current_item: LocalDefId,
1174 impl<'tcx> TypePrivacyVisitor<'tcx> {
1175 /// Gets the type-checking results for the current body.
1176 /// As this will ICE if called outside bodies, only call when working with
1177 /// `Expr` or `Pat` nodes (they are guaranteed to be found only in bodies).
1179 fn typeck_results(&self) -> &'tcx ty::TypeckResults<'tcx> {
1180 self.maybe_typeck_results
1181 .expect("`TypePrivacyVisitor::typeck_results` called outside of body")
1184 fn item_is_accessible(&self, did: DefId) -> bool {
1185 def_id_visibility(self.tcx, did)
1187 .is_accessible_from(self.current_item.to_def_id(), self.tcx)
1190 // Take node-id of an expression or pattern and check its type for privacy.
1191 fn check_expr_pat_type(&mut self, id: hir::HirId, span: Span) -> bool {
1193 let typeck_results = self.typeck_results();
1194 if self.visit(typeck_results.node_type(id)) || self.visit(typeck_results.node_substs(id)) {
1197 if let Some(adjustments) = typeck_results.adjustments().get(id) {
1198 for adjustment in adjustments {
1199 if self.visit(adjustment.target) {
1207 fn check_def_id(&mut self, def_id: DefId, kind: &str, descr: &dyn fmt::Display) -> bool {
1208 let is_error = !self.item_is_accessible(def_id);
1212 .struct_span_err(self.span, &format!("{} `{}` is private", kind, descr))
1213 .span_label(self.span, &format!("private {}", kind))
1220 impl<'tcx> Visitor<'tcx> for TypePrivacyVisitor<'tcx> {
1221 type Map = Map<'tcx>;
1223 /// We want to visit items in the context of their containing
1224 /// module and so forth, so supply a crate for doing a deep walk.
1225 fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
1226 NestedVisitorMap::All(self.tcx.hir())
1229 fn visit_mod(&mut self, _m: &'tcx hir::Mod<'tcx>, _s: Span, _n: hir::HirId) {
1230 // Don't visit nested modules, since we run a separate visitor walk
1231 // for each module in `privacy_access_levels`
1234 fn visit_nested_body(&mut self, body: hir::BodyId) {
1235 let old_maybe_typeck_results =
1236 self.maybe_typeck_results.replace(self.tcx.typeck_body(body));
1237 let body = self.tcx.hir().body(body);
1238 self.visit_body(body);
1239 self.maybe_typeck_results = old_maybe_typeck_results;
1242 fn visit_ty(&mut self, hir_ty: &'tcx hir::Ty<'tcx>) {
1243 self.span = hir_ty.span;
1244 if let Some(typeck_results) = self.maybe_typeck_results {
1246 if self.visit(typeck_results.node_type(hir_ty.hir_id)) {
1250 // Types in signatures.
1251 // FIXME: This is very ineffective. Ideally each HIR type should be converted
1252 // into a semantic type only once and the result should be cached somehow.
1253 if self.visit(rustc_typeck::hir_ty_to_ty(self.tcx, hir_ty)) {
1258 intravisit::walk_ty(self, hir_ty);
1261 fn visit_trait_ref(&mut self, trait_ref: &'tcx hir::TraitRef<'tcx>) {
1262 self.span = trait_ref.path.span;
1263 if self.maybe_typeck_results.is_none() {
1264 // Avoid calling `hir_trait_to_predicates` in bodies, it will ICE.
1265 // The traits' privacy in bodies is already checked as a part of trait object types.
1266 let bounds = rustc_typeck::hir_trait_to_predicates(
1269 // NOTE: This isn't really right, but the actual type doesn't matter here. It's
1270 // just required by `ty::TraitRef`.
1271 self.tcx.types.never,
1274 for (trait_predicate, _, _) in bounds.trait_bounds {
1275 if self.visit_trait(trait_predicate.skip_binder()) {
1280 for (poly_predicate, _) in bounds.projection_bounds {
1282 if self.visit(poly_predicate.skip_binder().ty)
1283 || self.visit_trait(poly_predicate.skip_binder().projection_ty.trait_ref(tcx))
1290 intravisit::walk_trait_ref(self, trait_ref);
1293 // Check types of expressions
1294 fn visit_expr(&mut self, expr: &'tcx hir::Expr<'tcx>) {
1295 if self.check_expr_pat_type(expr.hir_id, expr.span) {
1296 // Do not check nested expressions if the error already happened.
1300 hir::ExprKind::Assign(_, ref rhs, _) | hir::ExprKind::Match(ref rhs, ..) => {
1301 // Do not report duplicate errors for `x = y` and `match x { ... }`.
1302 if self.check_expr_pat_type(rhs.hir_id, rhs.span) {
1306 hir::ExprKind::MethodCall(_, span, _, _) => {
1307 // Method calls have to be checked specially.
1309 if let Some(def_id) = self.typeck_results().type_dependent_def_id(expr.hir_id) {
1310 if self.visit(self.tcx.type_of(def_id)) {
1316 .delay_span_bug(expr.span, "no type-dependent def for method call");
1322 intravisit::walk_expr(self, expr);
1325 // Prohibit access to associated items with insufficient nominal visibility.
1327 // Additionally, until better reachability analysis for macros 2.0 is available,
1328 // we prohibit access to private statics from other crates, this allows to give
1329 // more code internal visibility at link time. (Access to private functions
1330 // is already prohibited by type privacy for function types.)
1331 fn visit_qpath(&mut self, qpath: &'tcx hir::QPath<'tcx>, id: hir::HirId, span: Span) {
1332 let def = match qpath {
1333 hir::QPath::Resolved(_, path) => match path.res {
1334 Res::Def(kind, def_id) => Some((kind, def_id)),
1337 hir::QPath::TypeRelative(..) | hir::QPath::LangItem(..) => self
1338 .maybe_typeck_results
1339 .and_then(|typeck_results| typeck_results.type_dependent_def(id)),
1341 let def = def.filter(|(kind, _)| match kind {
1342 DefKind::AssocFn | DefKind::AssocConst | DefKind::AssocTy | DefKind::Static => true,
1345 if let Some((kind, def_id)) = def {
1346 let is_local_static =
1347 if let DefKind::Static = kind { def_id.is_local() } else { false };
1348 if !self.item_is_accessible(def_id) && !is_local_static {
1349 let sess = self.tcx.sess;
1350 let sm = sess.source_map();
1351 let name = match qpath {
1352 hir::QPath::Resolved(..) | hir::QPath::LangItem(..) => {
1353 sm.span_to_snippet(qpath.span()).ok()
1355 hir::QPath::TypeRelative(_, segment) => Some(segment.ident.to_string()),
1357 let kind = kind.descr(def_id);
1358 let msg = match name {
1359 Some(name) => format!("{} `{}` is private", kind, name),
1360 None => format!("{} is private", kind),
1362 sess.struct_span_err(span, &msg)
1363 .span_label(span, &format!("private {}", kind))
1369 intravisit::walk_qpath(self, qpath, id, span);
1372 // Check types of patterns.
1373 fn visit_pat(&mut self, pattern: &'tcx hir::Pat<'tcx>) {
1374 if self.check_expr_pat_type(pattern.hir_id, pattern.span) {
1375 // Do not check nested patterns if the error already happened.
1379 intravisit::walk_pat(self, pattern);
1382 fn visit_local(&mut self, local: &'tcx hir::Local<'tcx>) {
1383 if let Some(ref init) = local.init {
1384 if self.check_expr_pat_type(init.hir_id, init.span) {
1385 // Do not report duplicate errors for `let x = y`.
1390 intravisit::walk_local(self, local);
1393 // Check types in item interfaces.
1394 fn visit_item(&mut self, item: &'tcx hir::Item<'tcx>) {
1395 let orig_current_item =
1396 mem::replace(&mut self.current_item, self.tcx.hir().local_def_id(item.hir_id));
1397 let old_maybe_typeck_results = self.maybe_typeck_results.take();
1398 intravisit::walk_item(self, item);
1399 self.maybe_typeck_results = old_maybe_typeck_results;
1400 self.current_item = orig_current_item;
1404 impl DefIdVisitor<'tcx> for TypePrivacyVisitor<'tcx> {
1405 fn tcx(&self) -> TyCtxt<'tcx> {
1408 fn visit_def_id(&mut self, def_id: DefId, kind: &str, descr: &dyn fmt::Display) -> bool {
1409 self.check_def_id(def_id, kind, descr)
1413 ///////////////////////////////////////////////////////////////////////////////
1414 /// Obsolete visitors for checking for private items in public interfaces.
1415 /// These visitors are supposed to be kept in frozen state and produce an
1416 /// "old error node set". For backward compatibility the new visitor reports
1417 /// warnings instead of hard errors when the erroneous node is not in this old set.
1418 ///////////////////////////////////////////////////////////////////////////////
1420 struct ObsoleteVisiblePrivateTypesVisitor<'a, 'tcx> {
1422 access_levels: &'a AccessLevels,
1424 // Set of errors produced by this obsolete visitor.
1425 old_error_set: HirIdSet,
1428 struct ObsoleteCheckTypeForPrivatenessVisitor<'a, 'b, 'tcx> {
1429 inner: &'a ObsoleteVisiblePrivateTypesVisitor<'b, 'tcx>,
1430 /// Whether the type refers to private types.
1431 contains_private: bool,
1432 /// Whether we've recurred at all (i.e., if we're pointing at the
1433 /// first type on which `visit_ty` was called).
1434 at_outer_type: bool,
1435 /// Whether that first type is a public path.
1436 outer_type_is_public_path: bool,
1439 impl<'a, 'tcx> ObsoleteVisiblePrivateTypesVisitor<'a, 'tcx> {
1440 fn path_is_private_type(&self, path: &hir::Path<'_>) -> bool {
1441 let did = match path.res {
1442 Res::PrimTy(..) | Res::SelfTy(..) | Res::Err => return false,
1443 res => res.def_id(),
1446 // A path can only be private if:
1447 // it's in this crate...
1448 if let Some(did) = did.as_local() {
1449 // .. and it corresponds to a private type in the AST (this returns
1450 // `None` for type parameters).
1451 match self.tcx.hir().find(self.tcx.hir().local_def_id_to_hir_id(did)) {
1452 Some(Node::Item(ref item)) => !item.vis.node.is_pub(),
1453 Some(_) | None => false,
1460 fn trait_is_public(&self, trait_id: hir::HirId) -> bool {
1461 // FIXME: this would preferably be using `exported_items`, but all
1462 // traits are exported currently (see `EmbargoVisitor.exported_trait`).
1463 self.access_levels.is_public(trait_id)
1466 fn check_generic_bound(&mut self, bound: &hir::GenericBound<'_>) {
1467 if let hir::GenericBound::Trait(ref trait_ref, _) = *bound {
1468 if self.path_is_private_type(&trait_ref.trait_ref.path) {
1469 self.old_error_set.insert(trait_ref.trait_ref.hir_ref_id);
1474 fn item_is_public(&self, id: &hir::HirId, vis: &hir::Visibility<'_>) -> bool {
1475 self.access_levels.is_reachable(*id) || vis.node.is_pub()
1479 impl<'a, 'b, 'tcx, 'v> Visitor<'v> for ObsoleteCheckTypeForPrivatenessVisitor<'a, 'b, 'tcx> {
1480 type Map = intravisit::ErasedMap<'v>;
1482 fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
1483 NestedVisitorMap::None
1486 fn visit_ty(&mut self, ty: &hir::Ty<'_>) {
1487 if let hir::TyKind::Path(hir::QPath::Resolved(_, ref path)) = ty.kind {
1488 if self.inner.path_is_private_type(path) {
1489 self.contains_private = true;
1490 // Found what we're looking for, so let's stop working.
1494 if let hir::TyKind::Path(_) = ty.kind {
1495 if self.at_outer_type {
1496 self.outer_type_is_public_path = true;
1499 self.at_outer_type = false;
1500 intravisit::walk_ty(self, ty)
1503 // Don't want to recurse into `[, .. expr]`.
1504 fn visit_expr(&mut self, _: &hir::Expr<'_>) {}
1507 impl<'a, 'tcx> Visitor<'tcx> for ObsoleteVisiblePrivateTypesVisitor<'a, 'tcx> {
1508 type Map = Map<'tcx>;
1510 /// We want to visit items in the context of their containing
1511 /// module and so forth, so supply a crate for doing a deep walk.
1512 fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
1513 NestedVisitorMap::All(self.tcx.hir())
1516 fn visit_item(&mut self, item: &'tcx hir::Item<'tcx>) {
1518 // Contents of a private mod can be re-exported, so we need
1519 // to check internals.
1520 hir::ItemKind::Mod(_) => {}
1522 // An `extern {}` doesn't introduce a new privacy
1523 // namespace (the contents have their own privacies).
1524 hir::ItemKind::ForeignMod(_) => {}
1526 hir::ItemKind::Trait(.., ref bounds, _) => {
1527 if !self.trait_is_public(item.hir_id) {
1531 for bound in bounds.iter() {
1532 self.check_generic_bound(bound)
1536 // Impls need some special handling to try to offer useful
1537 // error messages without (too many) false positives
1538 // (i.e., we could just return here to not check them at
1539 // all, or some worse estimation of whether an impl is
1540 // publicly visible).
1541 hir::ItemKind::Impl { generics: ref g, ref of_trait, ref self_ty, items, .. } => {
1542 // `impl [... for] Private` is never visible.
1543 let self_contains_private;
1544 // `impl [... for] Public<...>`, but not `impl [... for]
1545 // Vec<Public>` or `(Public,)`, etc.
1546 let self_is_public_path;
1548 // Check the properties of the `Self` type:
1550 let mut visitor = ObsoleteCheckTypeForPrivatenessVisitor {
1552 contains_private: false,
1553 at_outer_type: true,
1554 outer_type_is_public_path: false,
1556 visitor.visit_ty(&self_ty);
1557 self_contains_private = visitor.contains_private;
1558 self_is_public_path = visitor.outer_type_is_public_path;
1561 // Miscellaneous info about the impl:
1563 // `true` iff this is `impl Private for ...`.
1564 let not_private_trait = of_trait.as_ref().map_or(
1565 true, // no trait counts as public trait
1567 let did = tr.path.res.def_id();
1569 if let Some(did) = did.as_local() {
1570 self.trait_is_public(self.tcx.hir().local_def_id_to_hir_id(did))
1572 true // external traits must be public
1577 // `true` iff this is a trait impl or at least one method is public.
1579 // `impl Public { $( fn ...() {} )* }` is not visible.
1581 // This is required over just using the methods' privacy
1582 // directly because we might have `impl<T: Foo<Private>> ...`,
1583 // and we shouldn't warn about the generics if all the methods
1584 // are private (because `T` won't be visible externally).
1585 let trait_or_some_public_method = of_trait.is_some()
1586 || items.iter().any(|impl_item_ref| {
1587 let impl_item = self.tcx.hir().impl_item(impl_item_ref.id);
1588 match impl_item.kind {
1589 hir::ImplItemKind::Const(..) | hir::ImplItemKind::Fn(..) => {
1590 self.access_levels.is_reachable(impl_item_ref.id.hir_id)
1592 hir::ImplItemKind::TyAlias(_) => false,
1596 if !self_contains_private && not_private_trait && trait_or_some_public_method {
1597 intravisit::walk_generics(self, g);
1601 for impl_item_ref in items {
1602 // This is where we choose whether to walk down
1603 // further into the impl to check its items. We
1604 // should only walk into public items so that we
1605 // don't erroneously report errors for private
1606 // types in private items.
1607 let impl_item = self.tcx.hir().impl_item(impl_item_ref.id);
1608 match impl_item.kind {
1609 hir::ImplItemKind::Const(..) | hir::ImplItemKind::Fn(..)
1611 .item_is_public(&impl_item.hir_id, &impl_item.vis) =>
1613 intravisit::walk_impl_item(self, impl_item)
1615 hir::ImplItemKind::TyAlias(..) => {
1616 intravisit::walk_impl_item(self, impl_item)
1623 // Any private types in a trait impl fall into three
1625 // 1. mentioned in the trait definition
1626 // 2. mentioned in the type params/generics
1627 // 3. mentioned in the associated types of the impl
1629 // Those in 1. can only occur if the trait is in
1630 // this crate and will've been warned about on the
1631 // trait definition (there's no need to warn twice
1632 // so we don't check the methods).
1634 // Those in 2. are warned via walk_generics and this
1636 intravisit::walk_path(self, &tr.path);
1638 // Those in 3. are warned with this call.
1639 for impl_item_ref in items {
1640 let impl_item = self.tcx.hir().impl_item(impl_item_ref.id);
1641 if let hir::ImplItemKind::TyAlias(ref ty) = impl_item.kind {
1647 } else if of_trait.is_none() && self_is_public_path {
1648 // `impl Public<Private> { ... }`. Any public static
1649 // methods will be visible as `Public::foo`.
1650 let mut found_pub_static = false;
1651 for impl_item_ref in items {
1652 if self.item_is_public(&impl_item_ref.id.hir_id, &impl_item_ref.vis) {
1653 let impl_item = self.tcx.hir().impl_item(impl_item_ref.id);
1654 match impl_item_ref.kind {
1655 AssocItemKind::Const => {
1656 found_pub_static = true;
1657 intravisit::walk_impl_item(self, impl_item);
1659 AssocItemKind::Fn { has_self: false } => {
1660 found_pub_static = true;
1661 intravisit::walk_impl_item(self, impl_item);
1667 if found_pub_static {
1668 intravisit::walk_generics(self, g)
1674 // `type ... = ...;` can contain private types, because
1675 // we're introducing a new name.
1676 hir::ItemKind::TyAlias(..) => return,
1678 // Not at all public, so we don't care.
1679 _ if !self.item_is_public(&item.hir_id, &item.vis) => {
1686 // We've carefully constructed it so that if we're here, then
1687 // any `visit_ty`'s will be called on things that are in
1688 // public signatures, i.e., things that we're interested in for
1690 intravisit::walk_item(self, item);
1693 fn visit_generics(&mut self, generics: &'tcx hir::Generics<'tcx>) {
1694 for param in generics.params {
1695 for bound in param.bounds {
1696 self.check_generic_bound(bound);
1699 for predicate in generics.where_clause.predicates {
1701 hir::WherePredicate::BoundPredicate(bound_pred) => {
1702 for bound in bound_pred.bounds.iter() {
1703 self.check_generic_bound(bound)
1706 hir::WherePredicate::RegionPredicate(_) => {}
1707 hir::WherePredicate::EqPredicate(eq_pred) => {
1708 self.visit_ty(&eq_pred.rhs_ty);
1714 fn visit_foreign_item(&mut self, item: &'tcx hir::ForeignItem<'tcx>) {
1715 if self.access_levels.is_reachable(item.hir_id) {
1716 intravisit::walk_foreign_item(self, item)
1720 fn visit_ty(&mut self, t: &'tcx hir::Ty<'tcx>) {
1721 if let hir::TyKind::Path(hir::QPath::Resolved(_, ref path)) = t.kind {
1722 if self.path_is_private_type(path) {
1723 self.old_error_set.insert(t.hir_id);
1726 intravisit::walk_ty(self, t)
1731 v: &'tcx hir::Variant<'tcx>,
1732 g: &'tcx hir::Generics<'tcx>,
1733 item_id: hir::HirId,
1735 if self.access_levels.is_reachable(v.id) {
1736 self.in_variant = true;
1737 intravisit::walk_variant(self, v, g, item_id);
1738 self.in_variant = false;
1742 fn visit_struct_field(&mut self, s: &'tcx hir::StructField<'tcx>) {
1743 if s.vis.node.is_pub() || self.in_variant {
1744 intravisit::walk_struct_field(self, s);
1748 // We don't need to introspect into these at all: an
1749 // expression/block context can't possibly contain exported things.
1750 // (Making them no-ops stops us from traversing the whole AST without
1751 // having to be super careful about our `walk_...` calls above.)
1752 fn visit_block(&mut self, _: &'tcx hir::Block<'tcx>) {}
1753 fn visit_expr(&mut self, _: &'tcx hir::Expr<'tcx>) {}
1756 ///////////////////////////////////////////////////////////////////////////////
1757 /// SearchInterfaceForPrivateItemsVisitor traverses an item's interface and
1758 /// finds any private components in it.
1759 /// PrivateItemsInPublicInterfacesVisitor ensures there are no private types
1760 /// and traits in public interfaces.
1761 ///////////////////////////////////////////////////////////////////////////////
1763 struct SearchInterfaceForPrivateItemsVisitor<'tcx> {
1765 item_id: hir::HirId,
1768 /// The visitor checks that each component type is at least this visible.
1769 required_visibility: ty::Visibility,
1770 has_pub_restricted: bool,
1771 has_old_errors: bool,
1775 impl SearchInterfaceForPrivateItemsVisitor<'tcx> {
1776 fn generics(&mut self) -> &mut Self {
1777 for param in &self.tcx.generics_of(self.item_def_id).params {
1779 GenericParamDefKind::Lifetime => {}
1780 GenericParamDefKind::Type { has_default, .. } => {
1782 self.visit(self.tcx.type_of(param.def_id));
1785 GenericParamDefKind::Const => {
1786 self.visit(self.tcx.type_of(param.def_id));
1793 fn predicates(&mut self) -> &mut Self {
1794 // N.B., we use `explicit_predicates_of` and not `predicates_of`
1795 // because we don't want to report privacy errors due to where
1796 // clauses that the compiler inferred. We only want to
1797 // consider the ones that the user wrote. This is important
1798 // for the inferred outlives rules; see
1799 // `src/test/ui/rfc-2093-infer-outlives/privacy.rs`.
1800 self.visit_predicates(self.tcx.explicit_predicates_of(self.item_def_id));
1804 fn ty(&mut self) -> &mut Self {
1805 self.visit(self.tcx.type_of(self.item_def_id));
1809 fn check_def_id(&mut self, def_id: DefId, kind: &str, descr: &dyn fmt::Display) -> bool {
1810 if self.leaks_private_dep(def_id) {
1811 self.tcx.struct_span_lint_hir(
1812 lint::builtin::EXPORTED_PRIVATE_DEPENDENCIES,
1816 lint.build(&format!(
1817 "{} `{}` from private dependency '{}' in public \
1821 self.tcx.crate_name(def_id.krate)
1828 let hir_id = match def_id.as_local() {
1829 Some(def_id) => self.tcx.hir().local_def_id_to_hir_id(def_id),
1830 None => return false,
1833 let (vis, vis_span, vis_descr) = def_id_visibility(self.tcx, def_id);
1834 if !vis.is_at_least(self.required_visibility, self.tcx) {
1835 let make_msg = || format!("{} {} `{}` in public interface", vis_descr, kind, descr);
1836 if self.has_pub_restricted || self.has_old_errors || self.in_assoc_ty {
1837 let mut err = if kind == "trait" {
1838 struct_span_err!(self.tcx.sess, self.span, E0445, "{}", make_msg())
1840 struct_span_err!(self.tcx.sess, self.span, E0446, "{}", make_msg())
1842 err.span_label(self.span, format!("can't leak {} {}", vis_descr, kind));
1843 err.span_label(vis_span, format!("`{}` declared as {}", descr, vis_descr));
1846 let err_code = if kind == "trait" { "E0445" } else { "E0446" };
1847 self.tcx.struct_span_lint_hir(
1848 lint::builtin::PRIVATE_IN_PUBLIC,
1851 |lint| lint.build(&format!("{} (error {})", make_msg(), err_code)).emit(),
1859 /// An item is 'leaked' from a private dependency if all
1860 /// of the following are true:
1861 /// 1. It's contained within a public type
1862 /// 2. It comes from a private crate
1863 fn leaks_private_dep(&self, item_id: DefId) -> bool {
1864 let ret = self.required_visibility == ty::Visibility::Public
1865 && self.tcx.is_private_dep(item_id.krate);
1867 tracing::debug!("leaks_private_dep(item_id={:?})={}", item_id, ret);
1872 impl DefIdVisitor<'tcx> for SearchInterfaceForPrivateItemsVisitor<'tcx> {
1873 fn tcx(&self) -> TyCtxt<'tcx> {
1876 fn visit_def_id(&mut self, def_id: DefId, kind: &str, descr: &dyn fmt::Display) -> bool {
1877 self.check_def_id(def_id, kind, descr)
1881 struct PrivateItemsInPublicInterfacesVisitor<'a, 'tcx> {
1883 has_pub_restricted: bool,
1884 old_error_set: &'a HirIdSet,
1887 impl<'a, 'tcx> PrivateItemsInPublicInterfacesVisitor<'a, 'tcx> {
1890 item_id: hir::HirId,
1891 required_visibility: ty::Visibility,
1892 ) -> SearchInterfaceForPrivateItemsVisitor<'tcx> {
1893 let mut has_old_errors = false;
1895 // Slow path taken only if there any errors in the crate.
1896 for &id in self.old_error_set {
1897 // Walk up the nodes until we find `item_id` (or we hit a root).
1901 has_old_errors = true;
1904 let parent = self.tcx.hir().get_parent_node(id);
1916 SearchInterfaceForPrivateItemsVisitor {
1919 item_def_id: self.tcx.hir().local_def_id(item_id).to_def_id(),
1920 span: self.tcx.hir().span(item_id),
1921 required_visibility,
1922 has_pub_restricted: self.has_pub_restricted,
1928 fn check_assoc_item(
1931 assoc_item_kind: AssocItemKind,
1932 defaultness: hir::Defaultness,
1933 vis: ty::Visibility,
1935 let mut check = self.check(hir_id, vis);
1937 let (check_ty, is_assoc_ty) = match assoc_item_kind {
1938 AssocItemKind::Const | AssocItemKind::Fn { .. } => (true, false),
1939 AssocItemKind::Type => (defaultness.has_value(), true),
1941 check.in_assoc_ty = is_assoc_ty;
1942 check.generics().predicates();
1949 impl<'a, 'tcx> Visitor<'tcx> for PrivateItemsInPublicInterfacesVisitor<'a, 'tcx> {
1950 type Map = Map<'tcx>;
1952 fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
1953 NestedVisitorMap::OnlyBodies(self.tcx.hir())
1956 fn visit_item(&mut self, item: &'tcx hir::Item<'tcx>) {
1958 let item_visibility = ty::Visibility::from_hir(&item.vis, item.hir_id, tcx);
1961 // Crates are always public.
1962 hir::ItemKind::ExternCrate(..) => {}
1963 // All nested items are checked by `visit_item`.
1964 hir::ItemKind::Mod(..) => {}
1965 // Checked in resolve.
1966 hir::ItemKind::Use(..) => {}
1968 hir::ItemKind::GlobalAsm(..) => {}
1969 // Subitems of these items have inherited publicity.
1970 hir::ItemKind::Const(..)
1971 | hir::ItemKind::Static(..)
1972 | hir::ItemKind::Fn(..)
1973 | hir::ItemKind::TyAlias(..) => {
1974 self.check(item.hir_id, item_visibility).generics().predicates().ty();
1976 hir::ItemKind::OpaqueTy(..) => {
1977 // `ty()` for opaque types is the underlying type,
1978 // it's not a part of interface, so we skip it.
1979 self.check(item.hir_id, item_visibility).generics().predicates();
1981 hir::ItemKind::Trait(.., trait_item_refs) => {
1982 self.check(item.hir_id, item_visibility).generics().predicates();
1984 for trait_item_ref in trait_item_refs {
1985 self.check_assoc_item(
1986 trait_item_ref.id.hir_id,
1987 trait_item_ref.kind,
1988 trait_item_ref.defaultness,
1993 hir::ItemKind::TraitAlias(..) => {
1994 self.check(item.hir_id, item_visibility).generics().predicates();
1996 hir::ItemKind::Enum(ref def, _) => {
1997 self.check(item.hir_id, item_visibility).generics().predicates();
1999 for variant in def.variants {
2000 for field in variant.data.fields() {
2001 self.check(field.hir_id, item_visibility).ty();
2005 // Subitems of foreign modules have their own publicity.
2006 hir::ItemKind::ForeignMod(ref foreign_mod) => {
2007 for foreign_item in foreign_mod.items {
2008 let vis = ty::Visibility::from_hir(&foreign_item.vis, item.hir_id, tcx);
2009 self.check(foreign_item.hir_id, vis).generics().predicates().ty();
2012 // Subitems of structs and unions have their own publicity.
2013 hir::ItemKind::Struct(ref struct_def, _) | hir::ItemKind::Union(ref struct_def, _) => {
2014 self.check(item.hir_id, item_visibility).generics().predicates();
2016 for field in struct_def.fields() {
2017 let field_visibility = ty::Visibility::from_hir(&field.vis, item.hir_id, tcx);
2018 self.check(field.hir_id, min(item_visibility, field_visibility, tcx)).ty();
2021 // An inherent impl is public when its type is public
2022 // Subitems of inherent impls have their own publicity.
2023 // A trait impl is public when both its type and its trait are public
2024 // Subitems of trait impls have inherited publicity.
2025 hir::ItemKind::Impl { ref of_trait, items, .. } => {
2026 let impl_vis = ty::Visibility::of_impl(item.hir_id, tcx, &Default::default());
2027 self.check(item.hir_id, impl_vis).generics().predicates();
2028 for impl_item_ref in items {
2029 let impl_item = tcx.hir().impl_item(impl_item_ref.id);
2030 let impl_item_vis = if of_trait.is_none() {
2032 ty::Visibility::from_hir(&impl_item.vis, item.hir_id, tcx),
2039 self.check_assoc_item(
2040 impl_item_ref.id.hir_id,
2042 impl_item_ref.defaultness,
2051 pub fn provide(providers: &mut Providers) {
2052 *providers = Providers {
2053 privacy_access_levels,
2054 check_private_in_public,
2060 fn check_mod_privacy(tcx: TyCtxt<'_>, module_def_id: LocalDefId) {
2061 // Check privacy of names not checked in previous compilation stages.
2062 let mut visitor = NamePrivacyVisitor { tcx, maybe_typeck_results: None, current_item: None };
2063 let (module, span, hir_id) = tcx.hir().get_module(module_def_id);
2065 intravisit::walk_mod(&mut visitor, module, hir_id);
2067 // Check privacy of explicitly written types and traits as well as
2068 // inferred types of expressions and patterns.
2070 TypePrivacyVisitor { tcx, maybe_typeck_results: None, current_item: module_def_id, span };
2071 intravisit::walk_mod(&mut visitor, module, hir_id);
2074 fn privacy_access_levels(tcx: TyCtxt<'_>, krate: CrateNum) -> &AccessLevels {
2075 assert_eq!(krate, LOCAL_CRATE);
2077 // Build up a set of all exported items in the AST. This is a set of all
2078 // items which are reachable from external crates based on visibility.
2079 let mut visitor = EmbargoVisitor {
2081 access_levels: Default::default(),
2082 macro_reachable: Default::default(),
2083 prev_level: Some(AccessLevel::Public),
2087 intravisit::walk_crate(&mut visitor, tcx.hir().krate());
2088 if visitor.changed {
2089 visitor.changed = false;
2094 visitor.update(hir::CRATE_HIR_ID, Some(AccessLevel::Public));
2096 tcx.arena.alloc(visitor.access_levels)
2099 fn check_private_in_public(tcx: TyCtxt<'_>, krate: CrateNum) {
2100 assert_eq!(krate, LOCAL_CRATE);
2102 let access_levels = tcx.privacy_access_levels(LOCAL_CRATE);
2104 let krate = tcx.hir().krate();
2106 let mut visitor = ObsoleteVisiblePrivateTypesVisitor {
2108 access_levels: &access_levels,
2110 old_error_set: Default::default(),
2112 intravisit::walk_crate(&mut visitor, krate);
2114 let has_pub_restricted = {
2115 let mut pub_restricted_visitor = PubRestrictedVisitor { tcx, has_pub_restricted: false };
2116 intravisit::walk_crate(&mut pub_restricted_visitor, krate);
2117 pub_restricted_visitor.has_pub_restricted
2120 // Check for private types and traits in public interfaces.
2121 let mut visitor = PrivateItemsInPublicInterfacesVisitor {
2124 old_error_set: &visitor.old_error_set,
2126 krate.visit_all_item_likes(&mut DeepVisitor::new(&mut visitor));