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>
73 V: DefIdVisitor<'tcx> + ?Sized,
75 def_id_visitor: &'v mut V,
76 visited_opaque_tys: FxHashSet<DefId>,
77 dummy: PhantomData<TyCtxt<'tcx>>,
80 impl<'tcx, V> DefIdVisitorSkeleton<'_, 'tcx, V>
82 V: DefIdVisitor<'tcx> + ?Sized,
84 fn visit_trait(&mut self, trait_ref: TraitRef<'tcx>) -> bool {
85 let TraitRef { def_id, substs } = trait_ref;
86 self.def_id_visitor.visit_def_id(def_id, "trait", &trait_ref.print_only_trait_path())
87 || (!self.def_id_visitor.shallow() && substs.visit_with(self))
90 fn visit_predicates(&mut self, predicates: ty::GenericPredicates<'tcx>) -> bool {
91 let ty::GenericPredicates { parent: _, predicates } = predicates;
92 for (predicate, _span) in predicates {
93 match predicate.kind() {
94 ty::PredicateKind::Trait(poly_predicate, _) => {
95 let ty::TraitPredicate { trait_ref } = poly_predicate.skip_binder();
96 if self.visit_trait(trait_ref) {
100 ty::PredicateKind::Projection(poly_predicate) => {
101 let ty::ProjectionPredicate { projection_ty, ty } =
102 poly_predicate.skip_binder();
103 if ty.visit_with(self) {
106 if self.visit_trait(projection_ty.trait_ref(self.def_id_visitor.tcx())) {
110 ty::PredicateKind::TypeOutlives(poly_predicate) => {
111 let ty::OutlivesPredicate(ty, _region) = poly_predicate.skip_binder();
112 if ty.visit_with(self) {
116 ty::PredicateKind::RegionOutlives(..) => {}
117 _ => bug!("unexpected 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().as_local_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 attr::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);
284 attr::find_by_name(&attrs, sym::non_exhaustive).unwrap().span;
285 descr = "crate-visible";
288 return (ctor_vis, span, descr);
291 let item = match tcx.hir().get(parent_hir_id) {
292 Node::Item(item) => item,
293 node => bug!("unexpected node kind: {:?}", node),
295 let (mut ctor_vis, mut span, mut descr) = (
296 ty::Visibility::from_hir(&item.vis, parent_hir_id, tcx),
298 item.vis.node.descr(),
300 for field in vdata.fields() {
301 let field_vis = ty::Visibility::from_hir(&field.vis, hir_id, tcx);
302 if ctor_vis.is_at_least(field_vis, tcx) {
303 ctor_vis = field_vis;
304 span = field.vis.span;
305 descr = field.vis.node.descr();
309 // If the structure is marked as non_exhaustive then lower the
310 // visibility to within the crate.
311 if ctor_vis == ty::Visibility::Public {
313 tcx.adt_def(tcx.hir().get_parent_did(hir_id).to_def_id());
314 if adt_def.non_enum_variant().is_field_list_non_exhaustive() {
316 ty::Visibility::Restricted(DefId::local(CRATE_DEF_INDEX));
317 span = attr::find_by_name(&item.attrs, sym::non_exhaustive)
320 descr = "crate-visible";
324 return (ctor_vis, span, descr);
326 node => bug!("unexpected node kind: {:?}", node),
329 Node::Expr(expr) => {
331 ty::Visibility::Restricted(tcx.parent_module(expr.hir_id).to_def_id()),
336 node => bug!("unexpected node kind: {:?}", node),
338 (ty::Visibility::from_hir(vis, hir_id, tcx), vis.span, vis.node.descr())
341 let vis = tcx.visibility(def_id);
342 let descr = if vis == ty::Visibility::Public { "public" } else { "private" };
343 (vis, tcx.def_span(def_id), descr)
348 fn min(vis1: ty::Visibility, vis2: ty::Visibility, tcx: TyCtxt<'_>) -> ty::Visibility {
349 if vis1.is_at_least(vis2, tcx) { vis2 } else { vis1 }
352 ////////////////////////////////////////////////////////////////////////////////
353 /// Visitor used to determine if pub(restricted) is used anywhere in the crate.
355 /// This is done so that `private_in_public` warnings can be turned into hard errors
356 /// in crates that have been updated to use pub(restricted).
357 ////////////////////////////////////////////////////////////////////////////////
358 struct PubRestrictedVisitor<'tcx> {
360 has_pub_restricted: bool,
363 impl Visitor<'tcx> for PubRestrictedVisitor<'tcx> {
364 type Map = Map<'tcx>;
366 fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
367 NestedVisitorMap::All(self.tcx.hir())
369 fn visit_vis(&mut self, vis: &'tcx hir::Visibility<'tcx>) {
370 self.has_pub_restricted = self.has_pub_restricted || vis.node.is_pub_restricted();
374 ////////////////////////////////////////////////////////////////////////////////
375 /// Visitor used to determine impl visibility and reachability.
376 ////////////////////////////////////////////////////////////////////////////////
378 struct FindMin<'a, 'tcx, VL: VisibilityLike> {
380 access_levels: &'a AccessLevels,
384 impl<'a, 'tcx, VL: VisibilityLike> DefIdVisitor<'tcx> for FindMin<'a, 'tcx, VL> {
385 fn tcx(&self) -> TyCtxt<'tcx> {
388 fn shallow(&self) -> bool {
391 fn skip_assoc_tys(&self) -> bool {
394 fn visit_def_id(&mut self, def_id: DefId, _kind: &str, _descr: &dyn fmt::Display) -> bool {
395 self.min = VL::new_min(self, def_id);
400 trait VisibilityLike: Sized {
402 const SHALLOW: bool = false;
403 fn new_min(find: &FindMin<'_, '_, Self>, def_id: DefId) -> Self;
405 // Returns an over-approximation (`skip_assoc_tys` = true) of visibility due to
406 // associated types for which we can't determine visibility precisely.
407 fn of_impl(hir_id: hir::HirId, tcx: TyCtxt<'_>, access_levels: &AccessLevels) -> Self {
408 let mut find = FindMin { tcx, access_levels, min: Self::MAX };
409 let def_id = tcx.hir().local_def_id(hir_id);
410 find.visit(tcx.type_of(def_id));
411 if let Some(trait_ref) = tcx.impl_trait_ref(def_id) {
412 find.visit_trait(trait_ref);
417 impl VisibilityLike for ty::Visibility {
418 const MAX: Self = ty::Visibility::Public;
419 fn new_min(find: &FindMin<'_, '_, Self>, def_id: DefId) -> Self {
420 min(def_id_visibility(find.tcx, def_id).0, find.min, find.tcx)
423 impl VisibilityLike for Option<AccessLevel> {
424 const MAX: Self = Some(AccessLevel::Public);
425 // Type inference is very smart sometimes.
426 // It can make an impl reachable even some components of its type or trait are unreachable.
427 // E.g. methods of `impl ReachableTrait<UnreachableTy> for ReachableTy<UnreachableTy> { ... }`
428 // can be usable from other crates (#57264). So we skip substs when calculating reachability
429 // and consider an impl reachable if its "shallow" type and trait are reachable.
431 // The assumption we make here is that type-inference won't let you use an impl without knowing
432 // both "shallow" version of its self type and "shallow" version of its trait if it exists
433 // (which require reaching the `DefId`s in them).
434 const SHALLOW: bool = true;
435 fn new_min(find: &FindMin<'_, '_, Self>, def_id: DefId) -> Self {
437 if let Some(def_id) = def_id.as_local() {
438 let hir_id = find.tcx.hir().as_local_hir_id(def_id);
439 find.access_levels.map.get(&hir_id).cloned()
448 ////////////////////////////////////////////////////////////////////////////////
449 /// The embargo visitor, used to determine the exports of the AST.
450 ////////////////////////////////////////////////////////////////////////////////
452 struct EmbargoVisitor<'tcx> {
455 /// Accessibility levels for reachable nodes.
456 access_levels: AccessLevels,
457 /// A set of pairs corresponding to modules, where the first module is
458 /// reachable via a macro that's defined in the second module. This cannot
459 /// be represented as reachable because it can't handle the following case:
461 /// pub mod n { // Should be `Public`
462 /// pub(crate) mod p { // Should *not* be accessible
463 /// pub fn f() -> i32 { 12 } // Must be `Reachable`
469 macro_reachable: FxHashSet<(hir::HirId, DefId)>,
470 /// Previous accessibility level; `None` means unreachable.
471 prev_level: Option<AccessLevel>,
472 /// Has something changed in the level map?
476 struct ReachEverythingInTheInterfaceVisitor<'a, 'tcx> {
477 access_level: Option<AccessLevel>,
479 ev: &'a mut EmbargoVisitor<'tcx>,
482 impl EmbargoVisitor<'tcx> {
483 fn get(&self, id: hir::HirId) -> Option<AccessLevel> {
484 self.access_levels.map.get(&id).cloned()
487 /// Updates node level and returns the updated level.
488 fn update(&mut self, id: hir::HirId, level: Option<AccessLevel>) -> Option<AccessLevel> {
489 let old_level = self.get(id);
490 // Accessibility levels can only grow.
491 if level > old_level {
492 self.access_levels.map.insert(id, level.unwrap());
503 access_level: Option<AccessLevel>,
504 ) -> ReachEverythingInTheInterfaceVisitor<'_, 'tcx> {
505 ReachEverythingInTheInterfaceVisitor {
506 access_level: cmp::min(access_level, Some(AccessLevel::Reachable)),
507 item_def_id: self.tcx.hir().local_def_id(item_id).to_def_id(),
512 /// Updates the item as being reachable through a macro defined in the given
513 /// module. Returns `true` if the level has changed.
514 fn update_macro_reachable(&mut self, reachable_mod: hir::HirId, defining_mod: DefId) -> bool {
515 if self.macro_reachable.insert((reachable_mod, defining_mod)) {
516 self.update_macro_reachable_mod(reachable_mod, defining_mod);
523 fn update_macro_reachable_mod(&mut self, reachable_mod: hir::HirId, defining_mod: DefId) {
524 let module_def_id = self.tcx.hir().local_def_id(reachable_mod);
525 let module = self.tcx.hir().get_module(module_def_id).0;
526 for item_id in module.item_ids {
527 let hir_id = item_id.id;
528 let item_def_id = self.tcx.hir().local_def_id(hir_id);
529 let def_kind = self.tcx.def_kind(item_def_id);
530 let item = self.tcx.hir().expect_item(hir_id);
531 let vis = ty::Visibility::from_hir(&item.vis, hir_id, self.tcx);
532 self.update_macro_reachable_def(hir_id, def_kind, vis, defining_mod);
534 if let Some(exports) = self.tcx.module_exports(module_def_id) {
535 for export in exports {
536 if export.vis.is_accessible_from(defining_mod, self.tcx) {
537 if let Res::Def(def_kind, def_id) = export.res {
538 let vis = def_id_visibility(self.tcx, def_id).0;
539 if let Some(def_id) = def_id.as_local() {
540 let hir_id = self.tcx.hir().as_local_hir_id(def_id);
541 self.update_macro_reachable_def(hir_id, def_kind, vis, defining_mod);
549 fn update_macro_reachable_def(
556 let level = Some(AccessLevel::Reachable);
557 if let ty::Visibility::Public = vis {
558 self.update(hir_id, level);
561 // No type privacy, so can be directly marked as reachable.
565 | DefKind::TraitAlias
566 | DefKind::TyAlias => {
567 if vis.is_accessible_from(module, self.tcx) {
568 self.update(hir_id, level);
572 // We can't use a module name as the final segment of a path, except
573 // in use statements. Since re-export checking doesn't consider
574 // hygiene these don't need to be marked reachable. The contents of
575 // the module, however may be reachable.
577 if vis.is_accessible_from(module, self.tcx) {
578 self.update_macro_reachable(hir_id, module);
582 DefKind::Struct | DefKind::Union => {
583 // While structs and unions have type privacy, their fields do
585 if let ty::Visibility::Public = vis {
586 let item = self.tcx.hir().expect_item(hir_id);
587 if let hir::ItemKind::Struct(ref struct_def, _)
588 | hir::ItemKind::Union(ref struct_def, _) = item.kind
590 for field in struct_def.fields() {
592 ty::Visibility::from_hir(&field.vis, field.hir_id, self.tcx);
593 if field_vis.is_accessible_from(module, self.tcx) {
594 self.reach(field.hir_id, level).ty();
598 bug!("item {:?} with DefKind {:?}", item, def_kind);
603 // These have type privacy, so are not reachable unless they're
604 // public, or are not namespaced at all.
607 | DefKind::ConstParam
608 | DefKind::Ctor(_, _)
617 | DefKind::LifetimeParam
618 | DefKind::ExternCrate
620 | DefKind::ForeignMod
626 | DefKind::Generator => (),
630 /// Given the path segments of a `ItemKind::Use`, then we need
631 /// to update the visibility of the intermediate use so that it isn't linted
632 /// by `unreachable_pub`.
634 /// This isn't trivial as `path.res` has the `DefId` of the eventual target
635 /// of the use statement not of the next intermediate use statement.
637 /// To do this, consider the last two segments of the path to our intermediate
638 /// use statement. We expect the penultimate segment to be a module and the
639 /// last segment to be the name of the item we are exporting. We can then
640 /// look at the items contained in the module for the use statement with that
641 /// name and update that item's visibility.
643 /// FIXME: This solution won't work with glob imports and doesn't respect
644 /// namespaces. See <https://github.com/rust-lang/rust/pull/57922#discussion_r251234202>.
645 fn update_visibility_of_intermediate_use_statements(
647 segments: &[hir::PathSegment<'_>],
649 if let Some([module, segment]) = segments.rchunks_exact(2).next() {
650 if let Some(item) = module
652 .and_then(|res| res.mod_def_id())
653 // If the module is `self`, i.e. the current crate,
654 // there will be no corresponding item.
655 .filter(|def_id| def_id.index != CRATE_DEF_INDEX || def_id.krate != LOCAL_CRATE)
657 def_id.as_local().map(|def_id| self.tcx.hir().as_local_hir_id(def_id))
659 .map(|module_hir_id| self.tcx.hir().expect_item(module_hir_id))
661 if let hir::ItemKind::Mod(m) = &item.kind {
662 for item_id in m.item_ids {
663 let item = self.tcx.hir().expect_item(item_id.id);
664 let def_id = self.tcx.hir().local_def_id(item_id.id);
665 if !self.tcx.hygienic_eq(segment.ident, item.ident, def_id.to_def_id()) {
668 if let hir::ItemKind::Use(..) = item.kind {
669 self.update(item.hir_id, Some(AccessLevel::Exported));
678 impl Visitor<'tcx> for EmbargoVisitor<'tcx> {
679 type Map = Map<'tcx>;
681 /// We want to visit items in the context of their containing
682 /// module and so forth, so supply a crate for doing a deep walk.
683 fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
684 NestedVisitorMap::All(self.tcx.hir())
687 fn visit_item(&mut self, item: &'tcx hir::Item<'tcx>) {
688 let inherited_item_level = match item.kind {
689 hir::ItemKind::Impl { .. } => {
690 Option::<AccessLevel>::of_impl(item.hir_id, self.tcx, &self.access_levels)
692 // Foreign modules inherit level from parents.
693 hir::ItemKind::ForeignMod(..) => self.prev_level,
694 // Other `pub` items inherit levels from parents.
695 hir::ItemKind::Const(..)
696 | hir::ItemKind::Enum(..)
697 | hir::ItemKind::ExternCrate(..)
698 | hir::ItemKind::GlobalAsm(..)
699 | hir::ItemKind::Fn(..)
700 | hir::ItemKind::Mod(..)
701 | hir::ItemKind::Static(..)
702 | hir::ItemKind::Struct(..)
703 | hir::ItemKind::Trait(..)
704 | hir::ItemKind::TraitAlias(..)
705 | hir::ItemKind::OpaqueTy(..)
706 | hir::ItemKind::TyAlias(..)
707 | hir::ItemKind::Union(..)
708 | hir::ItemKind::Use(..) => {
709 if item.vis.node.is_pub() {
717 // Update level of the item itself.
718 let item_level = self.update(item.hir_id, inherited_item_level);
720 // Update levels of nested things.
722 hir::ItemKind::Enum(ref def, _) => {
723 for variant in def.variants {
724 let variant_level = self.update(variant.id, item_level);
725 if let Some(ctor_hir_id) = variant.data.ctor_hir_id() {
726 self.update(ctor_hir_id, item_level);
728 for field in variant.data.fields() {
729 self.update(field.hir_id, variant_level);
733 hir::ItemKind::Impl { ref of_trait, items, .. } => {
734 for impl_item_ref in items {
735 if of_trait.is_some() || impl_item_ref.vis.node.is_pub() {
736 self.update(impl_item_ref.id.hir_id, item_level);
740 hir::ItemKind::Trait(.., trait_item_refs) => {
741 for trait_item_ref in trait_item_refs {
742 self.update(trait_item_ref.id.hir_id, item_level);
745 hir::ItemKind::Struct(ref def, _) | hir::ItemKind::Union(ref def, _) => {
746 if let Some(ctor_hir_id) = def.ctor_hir_id() {
747 self.update(ctor_hir_id, item_level);
749 for field in def.fields() {
750 if field.vis.node.is_pub() {
751 self.update(field.hir_id, item_level);
755 hir::ItemKind::ForeignMod(ref foreign_mod) => {
756 for foreign_item in foreign_mod.items {
757 if foreign_item.vis.node.is_pub() {
758 self.update(foreign_item.hir_id, item_level);
762 hir::ItemKind::OpaqueTy(..)
763 | hir::ItemKind::Use(..)
764 | hir::ItemKind::Static(..)
765 | hir::ItemKind::Const(..)
766 | hir::ItemKind::GlobalAsm(..)
767 | hir::ItemKind::TyAlias(..)
768 | hir::ItemKind::Mod(..)
769 | hir::ItemKind::TraitAlias(..)
770 | hir::ItemKind::Fn(..)
771 | hir::ItemKind::ExternCrate(..) => {}
774 // Mark all items in interfaces of reachable items as reachable.
776 // The interface is empty.
777 hir::ItemKind::ExternCrate(..) => {}
778 // All nested items are checked by `visit_item`.
779 hir::ItemKind::Mod(..) => {}
780 // Re-exports are handled in `visit_mod`. However, in order to avoid looping over
781 // all of the items of a mod in `visit_mod` looking for use statements, we handle
782 // making sure that intermediate use statements have their visibilities updated here.
783 hir::ItemKind::Use(ref path, _) => {
784 if item_level.is_some() {
785 self.update_visibility_of_intermediate_use_statements(path.segments.as_ref());
788 // The interface is empty.
789 hir::ItemKind::GlobalAsm(..) => {}
790 hir::ItemKind::OpaqueTy(..) => {
791 // FIXME: This is some serious pessimization intended to workaround deficiencies
792 // in the reachability pass (`middle/reachable.rs`). Types are marked as link-time
793 // reachable if they are returned via `impl Trait`, even from private functions.
794 let exist_level = cmp::max(item_level, Some(AccessLevel::ReachableFromImplTrait));
795 self.reach(item.hir_id, exist_level).generics().predicates().ty();
798 hir::ItemKind::Const(..)
799 | hir::ItemKind::Static(..)
800 | hir::ItemKind::Fn(..)
801 | hir::ItemKind::TyAlias(..) => {
802 if item_level.is_some() {
803 self.reach(item.hir_id, item_level).generics().predicates().ty();
806 hir::ItemKind::Trait(.., trait_item_refs) => {
807 if item_level.is_some() {
808 self.reach(item.hir_id, item_level).generics().predicates();
810 for trait_item_ref in trait_item_refs {
811 let mut reach = self.reach(trait_item_ref.id.hir_id, item_level);
812 reach.generics().predicates();
814 if trait_item_ref.kind == AssocItemKind::Type
815 && !trait_item_ref.defaultness.has_value()
824 hir::ItemKind::TraitAlias(..) => {
825 if item_level.is_some() {
826 self.reach(item.hir_id, item_level).generics().predicates();
829 // Visit everything except for private impl items.
830 hir::ItemKind::Impl { items, .. } => {
831 if item_level.is_some() {
832 self.reach(item.hir_id, item_level).generics().predicates().ty().trait_ref();
834 for impl_item_ref in items {
835 let impl_item_level = self.get(impl_item_ref.id.hir_id);
836 if impl_item_level.is_some() {
837 self.reach(impl_item_ref.id.hir_id, impl_item_level)
846 // Visit everything, but enum variants have their own levels.
847 hir::ItemKind::Enum(ref def, _) => {
848 if item_level.is_some() {
849 self.reach(item.hir_id, item_level).generics().predicates();
851 for variant in def.variants {
852 let variant_level = self.get(variant.id);
853 if variant_level.is_some() {
854 for field in variant.data.fields() {
855 self.reach(field.hir_id, variant_level).ty();
857 // Corner case: if the variant is reachable, but its
858 // enum is not, make the enum reachable as well.
859 self.update(item.hir_id, variant_level);
863 // Visit everything, but foreign items have their own levels.
864 hir::ItemKind::ForeignMod(ref foreign_mod) => {
865 for foreign_item in foreign_mod.items {
866 let foreign_item_level = self.get(foreign_item.hir_id);
867 if foreign_item_level.is_some() {
868 self.reach(foreign_item.hir_id, foreign_item_level)
875 // Visit everything except for private fields.
876 hir::ItemKind::Struct(ref struct_def, _) | hir::ItemKind::Union(ref struct_def, _) => {
877 if item_level.is_some() {
878 self.reach(item.hir_id, item_level).generics().predicates();
879 for field in struct_def.fields() {
880 let field_level = self.get(field.hir_id);
881 if field_level.is_some() {
882 self.reach(field.hir_id, field_level).ty();
889 let orig_level = mem::replace(&mut self.prev_level, item_level);
890 intravisit::walk_item(self, item);
891 self.prev_level = orig_level;
894 fn visit_block(&mut self, b: &'tcx hir::Block<'tcx>) {
895 // Blocks can have public items, for example impls, but they always
896 // start as completely private regardless of publicity of a function,
897 // constant, type, field, etc., in which this block resides.
898 let orig_level = mem::replace(&mut self.prev_level, None);
899 intravisit::walk_block(self, b);
900 self.prev_level = orig_level;
903 fn visit_mod(&mut self, m: &'tcx hir::Mod<'tcx>, _sp: Span, id: hir::HirId) {
904 // This code is here instead of in visit_item so that the
905 // crate module gets processed as well.
906 if self.prev_level.is_some() {
907 let def_id = self.tcx.hir().local_def_id(id);
908 if let Some(exports) = self.tcx.module_exports(def_id) {
909 for export in exports.iter() {
910 if export.vis == ty::Visibility::Public {
911 if let Some(def_id) = export.res.opt_def_id() {
912 if let Some(def_id) = def_id.as_local() {
913 let hir_id = self.tcx.hir().as_local_hir_id(def_id);
914 self.update(hir_id, Some(AccessLevel::Exported));
922 intravisit::walk_mod(self, m, id);
925 fn visit_macro_def(&mut self, md: &'tcx hir::MacroDef<'tcx>) {
926 if attr::find_transparency(&md.attrs, md.ast.macro_rules).0 != Transparency::Opaque {
927 self.update(md.hir_id, Some(AccessLevel::Public));
931 let macro_module_def_id =
932 ty::DefIdTree::parent(self.tcx, self.tcx.hir().local_def_id(md.hir_id).to_def_id())
934 // FIXME(#71104) Should really be using just `as_local_hir_id` but
935 // some `DefId` do not seem to have a corresponding HirId.
936 let hir_id = macro_module_def_id
938 .and_then(|def_id| self.tcx.hir().opt_local_def_id_to_hir_id(def_id));
939 let mut module_id = match hir_id {
940 Some(module_id) if self.tcx.hir().is_hir_id_module(module_id) => module_id,
941 // `module_id` doesn't correspond to a `mod`, return early (#63164, #65252).
944 let level = if md.vis.node.is_pub() { self.get(module_id) } else { None };
945 let new_level = self.update(md.hir_id, level);
946 if new_level.is_none() {
951 let changed_reachability = self.update_macro_reachable(module_id, macro_module_def_id);
952 if changed_reachability || module_id == hir::CRATE_HIR_ID {
955 module_id = self.tcx.hir().get_parent_node(module_id);
960 impl ReachEverythingInTheInterfaceVisitor<'_, 'tcx> {
961 fn generics(&mut self) -> &mut Self {
962 for param in &self.ev.tcx.generics_of(self.item_def_id).params {
964 GenericParamDefKind::Lifetime => {}
965 GenericParamDefKind::Type { has_default, .. } => {
967 self.visit(self.ev.tcx.type_of(param.def_id));
970 GenericParamDefKind::Const => {
971 self.visit(self.ev.tcx.type_of(param.def_id));
978 fn predicates(&mut self) -> &mut Self {
979 self.visit_predicates(self.ev.tcx.predicates_of(self.item_def_id));
983 fn ty(&mut self) -> &mut Self {
984 self.visit(self.ev.tcx.type_of(self.item_def_id));
988 fn trait_ref(&mut self) -> &mut Self {
989 if let Some(trait_ref) = self.ev.tcx.impl_trait_ref(self.item_def_id) {
990 self.visit_trait(trait_ref);
996 impl DefIdVisitor<'tcx> for ReachEverythingInTheInterfaceVisitor<'_, 'tcx> {
997 fn tcx(&self) -> TyCtxt<'tcx> {
1000 fn visit_def_id(&mut self, def_id: DefId, _kind: &str, _descr: &dyn fmt::Display) -> bool {
1001 if let Some(def_id) = def_id.as_local() {
1002 let hir_id = self.ev.tcx.hir().as_local_hir_id(def_id);
1003 if let ((ty::Visibility::Public, ..), _)
1004 | (_, Some(AccessLevel::ReachableFromImplTrait)) =
1005 (def_id_visibility(self.tcx(), def_id.to_def_id()), self.access_level)
1007 self.ev.update(hir_id, self.access_level);
1014 //////////////////////////////////////////////////////////////////////////////////////
1015 /// Name privacy visitor, checks privacy and reports violations.
1016 /// Most of name privacy checks are performed during the main resolution phase,
1017 /// or later in type checking when field accesses and associated items are resolved.
1018 /// This pass performs remaining checks for fields in struct expressions and patterns.
1019 //////////////////////////////////////////////////////////////////////////////////////
1021 struct NamePrivacyVisitor<'tcx> {
1023 maybe_typeck_results: Option<&'tcx ty::TypeckResults<'tcx>>,
1024 current_item: Option<hir::HirId>,
1027 impl<'tcx> NamePrivacyVisitor<'tcx> {
1028 /// Gets the type-checking results for the current body.
1029 /// As this will ICE if called outside bodies, only call when working with
1030 /// `Expr` or `Pat` nodes (they are guaranteed to be found only in bodies).
1032 fn typeck_results(&self) -> &'tcx ty::TypeckResults<'tcx> {
1033 self.maybe_typeck_results
1034 .expect("`NamePrivacyVisitor::typeck_results` called outside of body")
1037 // Checks that a field in a struct constructor (expression or pattern) is accessible.
1040 use_ctxt: Span, // syntax context of the field name at the use site
1041 span: Span, // span of the field pattern, e.g., `x: 0`
1042 def: &'tcx ty::AdtDef, // definition of the struct or enum
1043 field: &'tcx ty::FieldDef,
1044 in_update_syntax: bool,
1046 // definition of the field
1047 let ident = Ident::new(kw::Invalid, use_ctxt);
1048 let current_hir = self.current_item.unwrap();
1049 let def_id = self.tcx.adjust_ident_and_get_scope(ident, def.did, current_hir).1;
1050 if !def.is_enum() && !field.vis.is_accessible_from(def_id, self.tcx) {
1051 let label = if in_update_syntax {
1052 format!("field `{}` is private", field.ident)
1054 "private field".to_string()
1061 "field `{}` of {} `{}` is private",
1063 def.variant_descr(),
1064 self.tcx.def_path_str(def.did)
1066 .span_label(span, label)
1072 impl<'tcx> Visitor<'tcx> for NamePrivacyVisitor<'tcx> {
1073 type Map = Map<'tcx>;
1075 /// We want to visit items in the context of their containing
1076 /// module and so forth, so supply a crate for doing a deep walk.
1077 fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
1078 NestedVisitorMap::All(self.tcx.hir())
1081 fn visit_mod(&mut self, _m: &'tcx hir::Mod<'tcx>, _s: Span, _n: hir::HirId) {
1082 // Don't visit nested modules, since we run a separate visitor walk
1083 // for each module in `privacy_access_levels`
1086 fn visit_nested_body(&mut self, body: hir::BodyId) {
1087 let old_maybe_typeck_results =
1088 self.maybe_typeck_results.replace(self.tcx.typeck_body(body));
1089 let body = self.tcx.hir().body(body);
1090 self.visit_body(body);
1091 self.maybe_typeck_results = old_maybe_typeck_results;
1094 fn visit_item(&mut self, item: &'tcx hir::Item<'tcx>) {
1095 let orig_current_item = self.current_item.replace(item.hir_id);
1096 intravisit::walk_item(self, item);
1097 self.current_item = orig_current_item;
1100 fn visit_expr(&mut self, expr: &'tcx hir::Expr<'tcx>) {
1101 if let hir::ExprKind::Struct(ref qpath, fields, ref base) = expr.kind {
1102 let res = self.typeck_results().qpath_res(qpath, expr.hir_id);
1103 let adt = self.typeck_results().expr_ty(expr).ty_adt_def().unwrap();
1104 let variant = adt.variant_of_res(res);
1105 if let Some(ref base) = *base {
1106 // If the expression uses FRU we need to make sure all the unmentioned fields
1107 // are checked for privacy (RFC 736). Rather than computing the set of
1108 // unmentioned fields, just check them all.
1109 for (vf_index, variant_field) in variant.fields.iter().enumerate() {
1110 let field = fields.iter().find(|f| {
1111 self.tcx.field_index(f.hir_id, self.typeck_results()) == vf_index
1113 let (use_ctxt, span) = match field {
1114 Some(field) => (field.ident.span, field.span),
1115 None => (base.span, base.span),
1117 self.check_field(use_ctxt, span, adt, variant_field, true);
1120 for field in fields {
1121 let use_ctxt = field.ident.span;
1122 let index = self.tcx.field_index(field.hir_id, self.typeck_results());
1123 self.check_field(use_ctxt, field.span, adt, &variant.fields[index], false);
1128 intravisit::walk_expr(self, expr);
1131 fn visit_pat(&mut self, pat: &'tcx hir::Pat<'tcx>) {
1132 if let PatKind::Struct(ref qpath, fields, _) = pat.kind {
1133 let res = self.typeck_results().qpath_res(qpath, pat.hir_id);
1134 let adt = self.typeck_results().pat_ty(pat).ty_adt_def().unwrap();
1135 let variant = adt.variant_of_res(res);
1136 for field in fields {
1137 let use_ctxt = field.ident.span;
1138 let index = self.tcx.field_index(field.hir_id, self.typeck_results());
1139 self.check_field(use_ctxt, field.span, adt, &variant.fields[index], false);
1143 intravisit::walk_pat(self, pat);
1147 ////////////////////////////////////////////////////////////////////////////////////////////
1148 /// Type privacy visitor, checks types for privacy and reports violations.
1149 /// Both explicitly written types and inferred types of expressions and patters are checked.
1150 /// Checks are performed on "semantic" types regardless of names and their hygiene.
1151 ////////////////////////////////////////////////////////////////////////////////////////////
1153 struct TypePrivacyVisitor<'tcx> {
1155 maybe_typeck_results: Option<&'tcx ty::TypeckResults<'tcx>>,
1156 current_item: LocalDefId,
1160 impl<'tcx> TypePrivacyVisitor<'tcx> {
1161 /// Gets the type-checking results for the current body.
1162 /// As this will ICE if called outside bodies, only call when working with
1163 /// `Expr` or `Pat` nodes (they are guaranteed to be found only in bodies).
1165 fn typeck_results(&self) -> &'tcx ty::TypeckResults<'tcx> {
1166 self.maybe_typeck_results
1167 .expect("`TypePrivacyVisitor::typeck_results` called outside of body")
1170 fn item_is_accessible(&self, did: DefId) -> bool {
1171 def_id_visibility(self.tcx, did)
1173 .is_accessible_from(self.current_item.to_def_id(), self.tcx)
1176 // Take node-id of an expression or pattern and check its type for privacy.
1177 fn check_expr_pat_type(&mut self, id: hir::HirId, span: Span) -> bool {
1179 let typeck_results = self.typeck_results();
1180 if self.visit(typeck_results.node_type(id)) || self.visit(typeck_results.node_substs(id)) {
1183 if let Some(adjustments) = typeck_results.adjustments().get(id) {
1184 for adjustment in adjustments {
1185 if self.visit(adjustment.target) {
1193 fn check_def_id(&mut self, def_id: DefId, kind: &str, descr: &dyn fmt::Display) -> bool {
1194 let is_error = !self.item_is_accessible(def_id);
1198 .struct_span_err(self.span, &format!("{} `{}` is private", kind, descr))
1199 .span_label(self.span, &format!("private {}", kind))
1206 impl<'tcx> Visitor<'tcx> for TypePrivacyVisitor<'tcx> {
1207 type Map = Map<'tcx>;
1209 /// We want to visit items in the context of their containing
1210 /// module and so forth, so supply a crate for doing a deep walk.
1211 fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
1212 NestedVisitorMap::All(self.tcx.hir())
1215 fn visit_mod(&mut self, _m: &'tcx hir::Mod<'tcx>, _s: Span, _n: hir::HirId) {
1216 // Don't visit nested modules, since we run a separate visitor walk
1217 // for each module in `privacy_access_levels`
1220 fn visit_nested_body(&mut self, body: hir::BodyId) {
1221 let old_maybe_typeck_results =
1222 self.maybe_typeck_results.replace(self.tcx.typeck_body(body));
1223 let body = self.tcx.hir().body(body);
1224 self.visit_body(body);
1225 self.maybe_typeck_results = old_maybe_typeck_results;
1228 fn visit_ty(&mut self, hir_ty: &'tcx hir::Ty<'tcx>) {
1229 self.span = hir_ty.span;
1230 if let Some(typeck_results) = self.maybe_typeck_results {
1232 if self.visit(typeck_results.node_type(hir_ty.hir_id)) {
1236 // Types in signatures.
1237 // FIXME: This is very ineffective. Ideally each HIR type should be converted
1238 // into a semantic type only once and the result should be cached somehow.
1239 if self.visit(rustc_typeck::hir_ty_to_ty(self.tcx, hir_ty)) {
1244 intravisit::walk_ty(self, hir_ty);
1247 fn visit_trait_ref(&mut self, trait_ref: &'tcx hir::TraitRef<'tcx>) {
1248 self.span = trait_ref.path.span;
1249 if self.maybe_typeck_results.is_none() {
1250 // Avoid calling `hir_trait_to_predicates` in bodies, it will ICE.
1251 // The traits' privacy in bodies is already checked as a part of trait object types.
1252 let bounds = rustc_typeck::hir_trait_to_predicates(
1255 // NOTE: This isn't really right, but the actual type doesn't matter here. It's
1256 // just required by `ty::TraitRef`.
1257 self.tcx.types.never,
1260 for (trait_predicate, _, _) in bounds.trait_bounds {
1261 if self.visit_trait(trait_predicate.skip_binder()) {
1266 for (poly_predicate, _) in bounds.projection_bounds {
1268 if self.visit(poly_predicate.skip_binder().ty)
1269 || self.visit_trait(poly_predicate.skip_binder().projection_ty.trait_ref(tcx))
1276 intravisit::walk_trait_ref(self, trait_ref);
1279 // Check types of expressions
1280 fn visit_expr(&mut self, expr: &'tcx hir::Expr<'tcx>) {
1281 if self.check_expr_pat_type(expr.hir_id, expr.span) {
1282 // Do not check nested expressions if the error already happened.
1286 hir::ExprKind::Assign(_, ref rhs, _) | hir::ExprKind::Match(ref rhs, ..) => {
1287 // Do not report duplicate errors for `x = y` and `match x { ... }`.
1288 if self.check_expr_pat_type(rhs.hir_id, rhs.span) {
1292 hir::ExprKind::MethodCall(_, span, _, _) => {
1293 // Method calls have to be checked specially.
1295 if let Some(def_id) = self.typeck_results().type_dependent_def_id(expr.hir_id) {
1296 if self.visit(self.tcx.type_of(def_id)) {
1302 .delay_span_bug(expr.span, "no type-dependent def for method call");
1308 intravisit::walk_expr(self, expr);
1311 // Prohibit access to associated items with insufficient nominal visibility.
1313 // Additionally, until better reachability analysis for macros 2.0 is available,
1314 // we prohibit access to private statics from other crates, this allows to give
1315 // more code internal visibility at link time. (Access to private functions
1316 // is already prohibited by type privacy for function types.)
1317 fn visit_qpath(&mut self, qpath: &'tcx hir::QPath<'tcx>, id: hir::HirId, span: Span) {
1318 let def = match qpath {
1319 hir::QPath::Resolved(_, path) => match path.res {
1320 Res::Def(kind, def_id) => Some((kind, def_id)),
1323 hir::QPath::TypeRelative(..) => self
1324 .maybe_typeck_results
1325 .and_then(|typeck_results| typeck_results.type_dependent_def(id)),
1327 let def = def.filter(|(kind, _)| match kind {
1328 DefKind::AssocFn | DefKind::AssocConst | DefKind::AssocTy | DefKind::Static => true,
1331 if let Some((kind, def_id)) = def {
1332 let is_local_static =
1333 if let DefKind::Static = kind { def_id.is_local() } else { false };
1334 if !self.item_is_accessible(def_id) && !is_local_static {
1335 let sess = self.tcx.sess;
1336 let sm = sess.source_map();
1337 let name = match qpath {
1338 hir::QPath::Resolved(_, path) => sm.span_to_snippet(path.span).ok(),
1339 hir::QPath::TypeRelative(_, segment) => Some(segment.ident.to_string()),
1341 let kind = kind.descr(def_id);
1342 let msg = match name {
1343 Some(name) => format!("{} `{}` is private", kind, name),
1344 None => format!("{} is private", kind),
1346 sess.struct_span_err(span, &msg)
1347 .span_label(span, &format!("private {}", kind))
1353 intravisit::walk_qpath(self, qpath, id, span);
1356 // Check types of patterns.
1357 fn visit_pat(&mut self, pattern: &'tcx hir::Pat<'tcx>) {
1358 if self.check_expr_pat_type(pattern.hir_id, pattern.span) {
1359 // Do not check nested patterns if the error already happened.
1363 intravisit::walk_pat(self, pattern);
1366 fn visit_local(&mut self, local: &'tcx hir::Local<'tcx>) {
1367 if let Some(ref init) = local.init {
1368 if self.check_expr_pat_type(init.hir_id, init.span) {
1369 // Do not report duplicate errors for `let x = y`.
1374 intravisit::walk_local(self, local);
1377 // Check types in item interfaces.
1378 fn visit_item(&mut self, item: &'tcx hir::Item<'tcx>) {
1379 let orig_current_item =
1380 mem::replace(&mut self.current_item, self.tcx.hir().local_def_id(item.hir_id));
1381 let old_maybe_typeck_results = self.maybe_typeck_results.take();
1382 intravisit::walk_item(self, item);
1383 self.maybe_typeck_results = old_maybe_typeck_results;
1384 self.current_item = orig_current_item;
1388 impl DefIdVisitor<'tcx> for TypePrivacyVisitor<'tcx> {
1389 fn tcx(&self) -> TyCtxt<'tcx> {
1392 fn visit_def_id(&mut self, def_id: DefId, kind: &str, descr: &dyn fmt::Display) -> bool {
1393 self.check_def_id(def_id, kind, descr)
1397 ///////////////////////////////////////////////////////////////////////////////
1398 /// Obsolete visitors for checking for private items in public interfaces.
1399 /// These visitors are supposed to be kept in frozen state and produce an
1400 /// "old error node set". For backward compatibility the new visitor reports
1401 /// warnings instead of hard errors when the erroneous node is not in this old set.
1402 ///////////////////////////////////////////////////////////////////////////////
1404 struct ObsoleteVisiblePrivateTypesVisitor<'a, 'tcx> {
1406 access_levels: &'a AccessLevels,
1408 // Set of errors produced by this obsolete visitor.
1409 old_error_set: HirIdSet,
1412 struct ObsoleteCheckTypeForPrivatenessVisitor<'a, 'b, 'tcx> {
1413 inner: &'a ObsoleteVisiblePrivateTypesVisitor<'b, 'tcx>,
1414 /// Whether the type refers to private types.
1415 contains_private: bool,
1416 /// Whether we've recurred at all (i.e., if we're pointing at the
1417 /// first type on which `visit_ty` was called).
1418 at_outer_type: bool,
1419 /// Whether that first type is a public path.
1420 outer_type_is_public_path: bool,
1423 impl<'a, 'tcx> ObsoleteVisiblePrivateTypesVisitor<'a, 'tcx> {
1424 fn path_is_private_type(&self, path: &hir::Path<'_>) -> bool {
1425 let did = match path.res {
1426 Res::PrimTy(..) | Res::SelfTy(..) | Res::Err => return false,
1427 res => res.def_id(),
1430 // A path can only be private if:
1431 // it's in this crate...
1432 if let Some(did) = did.as_local() {
1433 // .. and it corresponds to a private type in the AST (this returns
1434 // `None` for type parameters).
1435 match self.tcx.hir().find(self.tcx.hir().as_local_hir_id(did)) {
1436 Some(Node::Item(ref item)) => !item.vis.node.is_pub(),
1437 Some(_) | None => false,
1444 fn trait_is_public(&self, trait_id: hir::HirId) -> bool {
1445 // FIXME: this would preferably be using `exported_items`, but all
1446 // traits are exported currently (see `EmbargoVisitor.exported_trait`).
1447 self.access_levels.is_public(trait_id)
1450 fn check_generic_bound(&mut self, bound: &hir::GenericBound<'_>) {
1451 if let hir::GenericBound::Trait(ref trait_ref, _) = *bound {
1452 if self.path_is_private_type(&trait_ref.trait_ref.path) {
1453 self.old_error_set.insert(trait_ref.trait_ref.hir_ref_id);
1458 fn item_is_public(&self, id: &hir::HirId, vis: &hir::Visibility<'_>) -> bool {
1459 self.access_levels.is_reachable(*id) || vis.node.is_pub()
1463 impl<'a, 'b, 'tcx, 'v> Visitor<'v> for ObsoleteCheckTypeForPrivatenessVisitor<'a, 'b, 'tcx> {
1464 type Map = intravisit::ErasedMap<'v>;
1466 fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
1467 NestedVisitorMap::None
1470 fn visit_ty(&mut self, ty: &hir::Ty<'_>) {
1471 if let hir::TyKind::Path(hir::QPath::Resolved(_, ref path)) = ty.kind {
1472 if self.inner.path_is_private_type(path) {
1473 self.contains_private = true;
1474 // Found what we're looking for, so let's stop working.
1478 if let hir::TyKind::Path(_) = ty.kind {
1479 if self.at_outer_type {
1480 self.outer_type_is_public_path = true;
1483 self.at_outer_type = false;
1484 intravisit::walk_ty(self, ty)
1487 // Don't want to recurse into `[, .. expr]`.
1488 fn visit_expr(&mut self, _: &hir::Expr<'_>) {}
1491 impl<'a, 'tcx> Visitor<'tcx> for ObsoleteVisiblePrivateTypesVisitor<'a, 'tcx> {
1492 type Map = Map<'tcx>;
1494 /// We want to visit items in the context of their containing
1495 /// module and so forth, so supply a crate for doing a deep walk.
1496 fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
1497 NestedVisitorMap::All(self.tcx.hir())
1500 fn visit_item(&mut self, item: &'tcx hir::Item<'tcx>) {
1502 // Contents of a private mod can be re-exported, so we need
1503 // to check internals.
1504 hir::ItemKind::Mod(_) => {}
1506 // An `extern {}` doesn't introduce a new privacy
1507 // namespace (the contents have their own privacies).
1508 hir::ItemKind::ForeignMod(_) => {}
1510 hir::ItemKind::Trait(.., ref bounds, _) => {
1511 if !self.trait_is_public(item.hir_id) {
1515 for bound in bounds.iter() {
1516 self.check_generic_bound(bound)
1520 // Impls need some special handling to try to offer useful
1521 // error messages without (too many) false positives
1522 // (i.e., we could just return here to not check them at
1523 // all, or some worse estimation of whether an impl is
1524 // publicly visible).
1525 hir::ItemKind::Impl { generics: ref g, ref of_trait, ref self_ty, items, .. } => {
1526 // `impl [... for] Private` is never visible.
1527 let self_contains_private;
1528 // `impl [... for] Public<...>`, but not `impl [... for]
1529 // Vec<Public>` or `(Public,)`, etc.
1530 let self_is_public_path;
1532 // Check the properties of the `Self` type:
1534 let mut visitor = ObsoleteCheckTypeForPrivatenessVisitor {
1536 contains_private: false,
1537 at_outer_type: true,
1538 outer_type_is_public_path: false,
1540 visitor.visit_ty(&self_ty);
1541 self_contains_private = visitor.contains_private;
1542 self_is_public_path = visitor.outer_type_is_public_path;
1545 // Miscellaneous info about the impl:
1547 // `true` iff this is `impl Private for ...`.
1548 let not_private_trait = of_trait.as_ref().map_or(
1549 true, // no trait counts as public trait
1551 let did = tr.path.res.def_id();
1553 if let Some(did) = did.as_local() {
1554 self.trait_is_public(self.tcx.hir().as_local_hir_id(did))
1556 true // external traits must be public
1561 // `true` iff this is a trait impl or at least one method is public.
1563 // `impl Public { $( fn ...() {} )* }` is not visible.
1565 // This is required over just using the methods' privacy
1566 // directly because we might have `impl<T: Foo<Private>> ...`,
1567 // and we shouldn't warn about the generics if all the methods
1568 // are private (because `T` won't be visible externally).
1569 let trait_or_some_public_method = of_trait.is_some()
1570 || items.iter().any(|impl_item_ref| {
1571 let impl_item = self.tcx.hir().impl_item(impl_item_ref.id);
1572 match impl_item.kind {
1573 hir::ImplItemKind::Const(..) | hir::ImplItemKind::Fn(..) => {
1574 self.access_levels.is_reachable(impl_item_ref.id.hir_id)
1576 hir::ImplItemKind::TyAlias(_) => false,
1580 if !self_contains_private && not_private_trait && trait_or_some_public_method {
1581 intravisit::walk_generics(self, g);
1585 for impl_item_ref in items {
1586 // This is where we choose whether to walk down
1587 // further into the impl to check its items. We
1588 // should only walk into public items so that we
1589 // don't erroneously report errors for private
1590 // types in private items.
1591 let impl_item = self.tcx.hir().impl_item(impl_item_ref.id);
1592 match impl_item.kind {
1593 hir::ImplItemKind::Const(..) | hir::ImplItemKind::Fn(..)
1595 .item_is_public(&impl_item.hir_id, &impl_item.vis) =>
1597 intravisit::walk_impl_item(self, impl_item)
1599 hir::ImplItemKind::TyAlias(..) => {
1600 intravisit::walk_impl_item(self, impl_item)
1607 // Any private types in a trait impl fall into three
1609 // 1. mentioned in the trait definition
1610 // 2. mentioned in the type params/generics
1611 // 3. mentioned in the associated types of the impl
1613 // Those in 1. can only occur if the trait is in
1614 // this crate and will've been warned about on the
1615 // trait definition (there's no need to warn twice
1616 // so we don't check the methods).
1618 // Those in 2. are warned via walk_generics and this
1620 intravisit::walk_path(self, &tr.path);
1622 // Those in 3. are warned with this call.
1623 for impl_item_ref in items {
1624 let impl_item = self.tcx.hir().impl_item(impl_item_ref.id);
1625 if let hir::ImplItemKind::TyAlias(ref ty) = impl_item.kind {
1631 } else if of_trait.is_none() && self_is_public_path {
1632 // `impl Public<Private> { ... }`. Any public static
1633 // methods will be visible as `Public::foo`.
1634 let mut found_pub_static = false;
1635 for impl_item_ref in items {
1636 if self.item_is_public(&impl_item_ref.id.hir_id, &impl_item_ref.vis) {
1637 let impl_item = self.tcx.hir().impl_item(impl_item_ref.id);
1638 match impl_item_ref.kind {
1639 AssocItemKind::Const => {
1640 found_pub_static = true;
1641 intravisit::walk_impl_item(self, impl_item);
1643 AssocItemKind::Fn { has_self: false } => {
1644 found_pub_static = true;
1645 intravisit::walk_impl_item(self, impl_item);
1651 if found_pub_static {
1652 intravisit::walk_generics(self, g)
1658 // `type ... = ...;` can contain private types, because
1659 // we're introducing a new name.
1660 hir::ItemKind::TyAlias(..) => return,
1662 // Not at all public, so we don't care.
1663 _ if !self.item_is_public(&item.hir_id, &item.vis) => {
1670 // We've carefully constructed it so that if we're here, then
1671 // any `visit_ty`'s will be called on things that are in
1672 // public signatures, i.e., things that we're interested in for
1674 intravisit::walk_item(self, item);
1677 fn visit_generics(&mut self, generics: &'tcx hir::Generics<'tcx>) {
1678 for param in generics.params {
1679 for bound in param.bounds {
1680 self.check_generic_bound(bound);
1683 for predicate in generics.where_clause.predicates {
1685 hir::WherePredicate::BoundPredicate(bound_pred) => {
1686 for bound in bound_pred.bounds.iter() {
1687 self.check_generic_bound(bound)
1690 hir::WherePredicate::RegionPredicate(_) => {}
1691 hir::WherePredicate::EqPredicate(eq_pred) => {
1692 self.visit_ty(&eq_pred.rhs_ty);
1698 fn visit_foreign_item(&mut self, item: &'tcx hir::ForeignItem<'tcx>) {
1699 if self.access_levels.is_reachable(item.hir_id) {
1700 intravisit::walk_foreign_item(self, item)
1704 fn visit_ty(&mut self, t: &'tcx hir::Ty<'tcx>) {
1705 if let hir::TyKind::Path(hir::QPath::Resolved(_, ref path)) = t.kind {
1706 if self.path_is_private_type(path) {
1707 self.old_error_set.insert(t.hir_id);
1710 intravisit::walk_ty(self, t)
1715 v: &'tcx hir::Variant<'tcx>,
1716 g: &'tcx hir::Generics<'tcx>,
1717 item_id: hir::HirId,
1719 if self.access_levels.is_reachable(v.id) {
1720 self.in_variant = true;
1721 intravisit::walk_variant(self, v, g, item_id);
1722 self.in_variant = false;
1726 fn visit_struct_field(&mut self, s: &'tcx hir::StructField<'tcx>) {
1727 if s.vis.node.is_pub() || self.in_variant {
1728 intravisit::walk_struct_field(self, s);
1732 // We don't need to introspect into these at all: an
1733 // expression/block context can't possibly contain exported things.
1734 // (Making them no-ops stops us from traversing the whole AST without
1735 // having to be super careful about our `walk_...` calls above.)
1736 fn visit_block(&mut self, _: &'tcx hir::Block<'tcx>) {}
1737 fn visit_expr(&mut self, _: &'tcx hir::Expr<'tcx>) {}
1740 ///////////////////////////////////////////////////////////////////////////////
1741 /// SearchInterfaceForPrivateItemsVisitor traverses an item's interface and
1742 /// finds any private components in it.
1743 /// PrivateItemsInPublicInterfacesVisitor ensures there are no private types
1744 /// and traits in public interfaces.
1745 ///////////////////////////////////////////////////////////////////////////////
1747 struct SearchInterfaceForPrivateItemsVisitor<'tcx> {
1749 item_id: hir::HirId,
1752 /// The visitor checks that each component type is at least this visible.
1753 required_visibility: ty::Visibility,
1754 has_pub_restricted: bool,
1755 has_old_errors: bool,
1759 impl SearchInterfaceForPrivateItemsVisitor<'tcx> {
1760 fn generics(&mut self) -> &mut Self {
1761 for param in &self.tcx.generics_of(self.item_def_id).params {
1763 GenericParamDefKind::Lifetime => {}
1764 GenericParamDefKind::Type { has_default, .. } => {
1766 self.visit(self.tcx.type_of(param.def_id));
1769 GenericParamDefKind::Const => {
1770 self.visit(self.tcx.type_of(param.def_id));
1777 fn predicates(&mut self) -> &mut Self {
1778 // N.B., we use `explicit_predicates_of` and not `predicates_of`
1779 // because we don't want to report privacy errors due to where
1780 // clauses that the compiler inferred. We only want to
1781 // consider the ones that the user wrote. This is important
1782 // for the inferred outlives rules; see
1783 // `src/test/ui/rfc-2093-infer-outlives/privacy.rs`.
1784 self.visit_predicates(self.tcx.explicit_predicates_of(self.item_def_id));
1788 fn ty(&mut self) -> &mut Self {
1789 self.visit(self.tcx.type_of(self.item_def_id));
1793 fn check_def_id(&mut self, def_id: DefId, kind: &str, descr: &dyn fmt::Display) -> bool {
1794 if self.leaks_private_dep(def_id) {
1795 self.tcx.struct_span_lint_hir(
1796 lint::builtin::EXPORTED_PRIVATE_DEPENDENCIES,
1800 lint.build(&format!(
1801 "{} `{}` from private dependency '{}' in public \
1805 self.tcx.crate_name(def_id.krate)
1812 let hir_id = match def_id.as_local() {
1813 Some(def_id) => self.tcx.hir().as_local_hir_id(def_id),
1814 None => return false,
1817 let (vis, vis_span, vis_descr) = def_id_visibility(self.tcx, def_id);
1818 if !vis.is_at_least(self.required_visibility, self.tcx) {
1819 let make_msg = || format!("{} {} `{}` in public interface", vis_descr, kind, descr);
1820 if self.has_pub_restricted || self.has_old_errors || self.in_assoc_ty {
1821 let mut err = if kind == "trait" {
1822 struct_span_err!(self.tcx.sess, self.span, E0445, "{}", make_msg())
1824 struct_span_err!(self.tcx.sess, self.span, E0446, "{}", make_msg())
1826 err.span_label(self.span, format!("can't leak {} {}", vis_descr, kind));
1827 err.span_label(vis_span, format!("`{}` declared as {}", descr, vis_descr));
1830 let err_code = if kind == "trait" { "E0445" } else { "E0446" };
1831 self.tcx.struct_span_lint_hir(
1832 lint::builtin::PRIVATE_IN_PUBLIC,
1835 |lint| lint.build(&format!("{} (error {})", make_msg(), err_code)).emit(),
1843 /// An item is 'leaked' from a private dependency if all
1844 /// of the following are true:
1845 /// 1. It's contained within a public type
1846 /// 2. It comes from a private crate
1847 fn leaks_private_dep(&self, item_id: DefId) -> bool {
1848 let ret = self.required_visibility == ty::Visibility::Public
1849 && self.tcx.is_private_dep(item_id.krate);
1851 log::debug!("leaks_private_dep(item_id={:?})={}", item_id, ret);
1856 impl DefIdVisitor<'tcx> for SearchInterfaceForPrivateItemsVisitor<'tcx> {
1857 fn tcx(&self) -> TyCtxt<'tcx> {
1860 fn visit_def_id(&mut self, def_id: DefId, kind: &str, descr: &dyn fmt::Display) -> bool {
1861 self.check_def_id(def_id, kind, descr)
1865 struct PrivateItemsInPublicInterfacesVisitor<'a, 'tcx> {
1867 has_pub_restricted: bool,
1868 old_error_set: &'a HirIdSet,
1871 impl<'a, 'tcx> PrivateItemsInPublicInterfacesVisitor<'a, 'tcx> {
1874 item_id: hir::HirId,
1875 required_visibility: ty::Visibility,
1876 ) -> SearchInterfaceForPrivateItemsVisitor<'tcx> {
1877 let mut has_old_errors = false;
1879 // Slow path taken only if there any errors in the crate.
1880 for &id in self.old_error_set {
1881 // Walk up the nodes until we find `item_id` (or we hit a root).
1885 has_old_errors = true;
1888 let parent = self.tcx.hir().get_parent_node(id);
1900 SearchInterfaceForPrivateItemsVisitor {
1903 item_def_id: self.tcx.hir().local_def_id(item_id).to_def_id(),
1904 span: self.tcx.hir().span(item_id),
1905 required_visibility,
1906 has_pub_restricted: self.has_pub_restricted,
1912 fn check_assoc_item(
1915 assoc_item_kind: AssocItemKind,
1916 defaultness: hir::Defaultness,
1917 vis: ty::Visibility,
1919 let mut check = self.check(hir_id, vis);
1921 let (check_ty, is_assoc_ty) = match assoc_item_kind {
1922 AssocItemKind::Const | AssocItemKind::Fn { .. } => (true, false),
1923 AssocItemKind::Type => (defaultness.has_value(), true),
1925 check.in_assoc_ty = is_assoc_ty;
1926 check.generics().predicates();
1933 impl<'a, 'tcx> Visitor<'tcx> for PrivateItemsInPublicInterfacesVisitor<'a, 'tcx> {
1934 type Map = Map<'tcx>;
1936 fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
1937 NestedVisitorMap::OnlyBodies(self.tcx.hir())
1940 fn visit_item(&mut self, item: &'tcx hir::Item<'tcx>) {
1942 let item_visibility = ty::Visibility::from_hir(&item.vis, item.hir_id, tcx);
1945 // Crates are always public.
1946 hir::ItemKind::ExternCrate(..) => {}
1947 // All nested items are checked by `visit_item`.
1948 hir::ItemKind::Mod(..) => {}
1949 // Checked in resolve.
1950 hir::ItemKind::Use(..) => {}
1952 hir::ItemKind::GlobalAsm(..) => {}
1953 // Subitems of these items have inherited publicity.
1954 hir::ItemKind::Const(..)
1955 | hir::ItemKind::Static(..)
1956 | hir::ItemKind::Fn(..)
1957 | hir::ItemKind::TyAlias(..) => {
1958 self.check(item.hir_id, item_visibility).generics().predicates().ty();
1960 hir::ItemKind::OpaqueTy(..) => {
1961 // `ty()` for opaque types is the underlying type,
1962 // it's not a part of interface, so we skip it.
1963 self.check(item.hir_id, item_visibility).generics().predicates();
1965 hir::ItemKind::Trait(.., trait_item_refs) => {
1966 self.check(item.hir_id, item_visibility).generics().predicates();
1968 for trait_item_ref in trait_item_refs {
1969 self.check_assoc_item(
1970 trait_item_ref.id.hir_id,
1971 trait_item_ref.kind,
1972 trait_item_ref.defaultness,
1977 hir::ItemKind::TraitAlias(..) => {
1978 self.check(item.hir_id, item_visibility).generics().predicates();
1980 hir::ItemKind::Enum(ref def, _) => {
1981 self.check(item.hir_id, item_visibility).generics().predicates();
1983 for variant in def.variants {
1984 for field in variant.data.fields() {
1985 self.check(field.hir_id, item_visibility).ty();
1989 // Subitems of foreign modules have their own publicity.
1990 hir::ItemKind::ForeignMod(ref foreign_mod) => {
1991 for foreign_item in foreign_mod.items {
1992 let vis = ty::Visibility::from_hir(&foreign_item.vis, item.hir_id, tcx);
1993 self.check(foreign_item.hir_id, vis).generics().predicates().ty();
1996 // Subitems of structs and unions have their own publicity.
1997 hir::ItemKind::Struct(ref struct_def, _) | hir::ItemKind::Union(ref struct_def, _) => {
1998 self.check(item.hir_id, item_visibility).generics().predicates();
2000 for field in struct_def.fields() {
2001 let field_visibility = ty::Visibility::from_hir(&field.vis, item.hir_id, tcx);
2002 self.check(field.hir_id, min(item_visibility, field_visibility, tcx)).ty();
2005 // An inherent impl is public when its type is public
2006 // Subitems of inherent impls have their own publicity.
2007 // A trait impl is public when both its type and its trait are public
2008 // Subitems of trait impls have inherited publicity.
2009 hir::ItemKind::Impl { ref of_trait, items, .. } => {
2010 let impl_vis = ty::Visibility::of_impl(item.hir_id, tcx, &Default::default());
2011 self.check(item.hir_id, impl_vis).generics().predicates();
2012 for impl_item_ref in items {
2013 let impl_item = tcx.hir().impl_item(impl_item_ref.id);
2014 let impl_item_vis = if of_trait.is_none() {
2016 ty::Visibility::from_hir(&impl_item.vis, item.hir_id, tcx),
2023 self.check_assoc_item(
2024 impl_item_ref.id.hir_id,
2026 impl_item_ref.defaultness,
2035 pub fn provide(providers: &mut Providers) {
2036 *providers = Providers {
2037 privacy_access_levels,
2038 check_private_in_public,
2044 fn check_mod_privacy(tcx: TyCtxt<'_>, module_def_id: LocalDefId) {
2045 // Check privacy of names not checked in previous compilation stages.
2046 let mut visitor = NamePrivacyVisitor { tcx, maybe_typeck_results: None, current_item: None };
2047 let (module, span, hir_id) = tcx.hir().get_module(module_def_id);
2049 intravisit::walk_mod(&mut visitor, module, hir_id);
2051 // Check privacy of explicitly written types and traits as well as
2052 // inferred types of expressions and patterns.
2054 TypePrivacyVisitor { tcx, maybe_typeck_results: None, current_item: module_def_id, span };
2055 intravisit::walk_mod(&mut visitor, module, hir_id);
2058 fn privacy_access_levels(tcx: TyCtxt<'_>, krate: CrateNum) -> &AccessLevels {
2059 assert_eq!(krate, LOCAL_CRATE);
2061 // Build up a set of all exported items in the AST. This is a set of all
2062 // items which are reachable from external crates based on visibility.
2063 let mut visitor = EmbargoVisitor {
2065 access_levels: Default::default(),
2066 macro_reachable: Default::default(),
2067 prev_level: Some(AccessLevel::Public),
2071 intravisit::walk_crate(&mut visitor, tcx.hir().krate());
2072 if visitor.changed {
2073 visitor.changed = false;
2078 visitor.update(hir::CRATE_HIR_ID, Some(AccessLevel::Public));
2080 tcx.arena.alloc(visitor.access_levels)
2083 fn check_private_in_public(tcx: TyCtxt<'_>, krate: CrateNum) {
2084 assert_eq!(krate, LOCAL_CRATE);
2086 let access_levels = tcx.privacy_access_levels(LOCAL_CRATE);
2088 let krate = tcx.hir().krate();
2090 let mut visitor = ObsoleteVisiblePrivateTypesVisitor {
2092 access_levels: &access_levels,
2094 old_error_set: Default::default(),
2096 intravisit::walk_crate(&mut visitor, krate);
2098 let has_pub_restricted = {
2099 let mut pub_restricted_visitor = PubRestrictedVisitor { tcx, has_pub_restricted: false };
2100 intravisit::walk_crate(&mut pub_restricted_visitor, krate);
2101 pub_restricted_visitor.has_pub_restricted
2104 // Check for private types and traits in public interfaces.
2105 let mut visitor = PrivateItemsInPublicInterfacesVisitor {
2108 old_error_set: &visitor.old_error_set,
2110 krate.visit_all_item_likes(&mut DeepVisitor::new(&mut visitor));