1 #![doc(html_root_url = "https://doc.rust-lang.org/nightly/")]
3 #![feature(in_band_lifetimes)]
5 #![feature(rustc_diagnostic_macros)]
7 #![recursion_limit="256"]
9 #[macro_use] extern crate syntax;
12 use rustc::hir::{self, Node, PatKind, AssocItemKind};
13 use rustc::hir::def::{Res, DefKind};
14 use rustc::hir::def_id::{CRATE_DEF_INDEX, LOCAL_CRATE, CrateNum, DefId};
15 use rustc::hir::intravisit::{self, Visitor, NestedVisitorMap};
16 use rustc::hir::itemlikevisit::DeepVisitor;
18 use rustc::middle::privacy::{AccessLevel, AccessLevels};
19 use rustc::ty::{self, TyCtxt, Ty, TraitRef, TypeFoldable, GenericParamDefKind};
20 use rustc::ty::fold::TypeVisitor;
21 use rustc::ty::query::Providers;
22 use rustc::ty::subst::InternalSubsts;
23 use rustc::util::nodemap::HirIdSet;
24 use rustc_data_structures::fx::FxHashSet;
25 use syntax::ast::Ident;
27 use syntax::symbol::{kw, sym};
28 use syntax_pos::hygiene::Transparency;
31 use std::{cmp, fmt, mem};
32 use std::marker::PhantomData;
36 ////////////////////////////////////////////////////////////////////////////////
37 /// Generic infrastructure used to implement specific visitors below.
38 ////////////////////////////////////////////////////////////////////////////////
40 /// Implemented to visit all `DefId`s in a type.
41 /// Visiting `DefId`s is useful because visibilities and reachabilities are attached to them.
42 /// The idea is to visit "all components of a type", as documented in
43 /// https://github.com/rust-lang/rfcs/blob/master/text/2145-type-privacy.md#how-to-determine-visibility-of-a-type.
44 /// The default type visitor (`TypeVisitor`) does most of the job, but it has some shortcomings.
45 /// First, it doesn't have overridable `fn visit_trait_ref`, so we have to catch trait `DefId`s
46 /// manually. Second, it doesn't visit some type components like signatures of fn types, or traits
47 /// in `impl Trait`, see individual comments in `DefIdVisitorSkeleton::visit_ty`.
48 trait DefIdVisitor<'tcx> {
49 fn tcx(&self) -> TyCtxt<'tcx>;
50 fn shallow(&self) -> bool { false }
51 fn skip_assoc_tys(&self) -> bool { false }
52 fn visit_def_id(&mut self, def_id: DefId, kind: &str, descr: &dyn fmt::Display) -> bool;
54 /// Not overridden, but used to actually visit types and traits.
55 fn skeleton(&mut self) -> DefIdVisitorSkeleton<'_, 'tcx, Self> {
56 DefIdVisitorSkeleton {
58 visited_opaque_tys: Default::default(),
59 dummy: Default::default(),
62 fn visit(&mut self, ty_fragment: impl TypeFoldable<'tcx>) -> bool {
63 ty_fragment.visit_with(&mut self.skeleton())
65 fn visit_trait(&mut self, trait_ref: TraitRef<'tcx>) -> bool {
66 self.skeleton().visit_trait(trait_ref)
68 fn visit_predicates(&mut self, predicates: &ty::GenericPredicates<'tcx>) -> bool {
69 self.skeleton().visit_predicates(predicates)
73 struct DefIdVisitorSkeleton<'v, 'tcx, V>
75 V: DefIdVisitor<'tcx> + ?Sized,
77 def_id_visitor: &'v mut V,
78 visited_opaque_tys: FxHashSet<DefId>,
79 dummy: PhantomData<TyCtxt<'tcx>>,
82 impl<'tcx, V> DefIdVisitorSkeleton<'_, 'tcx, V>
84 V: DefIdVisitor<'tcx> + ?Sized,
86 fn visit_trait(&mut self, trait_ref: TraitRef<'tcx>) -> bool {
87 let TraitRef { def_id, substs } = trait_ref;
88 self.def_id_visitor.visit_def_id(def_id, "trait", &trait_ref) ||
89 (!self.def_id_visitor.shallow() && substs.visit_with(self))
92 fn visit_predicates(&mut self, predicates: &ty::GenericPredicates<'tcx>) -> bool {
93 let ty::GenericPredicates { parent: _, predicates } = predicates;
94 for (predicate, _span) in predicates {
96 ty::Predicate::Trait(poly_predicate) => {
97 let ty::TraitPredicate { trait_ref } = *poly_predicate.skip_binder();
98 if self.visit_trait(trait_ref) {
102 ty::Predicate::Projection(poly_predicate) => {
103 let ty::ProjectionPredicate { projection_ty, ty } =
104 *poly_predicate.skip_binder();
105 if ty.visit_with(self) {
108 if self.visit_trait(projection_ty.trait_ref(self.def_id_visitor.tcx())) {
112 ty::Predicate::TypeOutlives(poly_predicate) => {
113 let ty::OutlivesPredicate(ty, _region) = *poly_predicate.skip_binder();
114 if ty.visit_with(self) {
118 ty::Predicate::RegionOutlives(..) => {},
119 _ => bug!("unexpected predicate: {:?}", predicate),
126 impl<'tcx, V> TypeVisitor<'tcx> for DefIdVisitorSkeleton<'_, 'tcx, V>
128 V: DefIdVisitor<'tcx> + ?Sized,
130 fn visit_ty(&mut self, ty: Ty<'tcx>) -> bool {
131 let tcx = self.def_id_visitor.tcx();
132 // InternalSubsts are not visited here because they are visited below in `super_visit_with`.
134 ty::Adt(&ty::AdtDef { did: def_id, .. }, ..) |
135 ty::Foreign(def_id) |
136 ty::FnDef(def_id, ..) |
137 ty::Closure(def_id, ..) |
138 ty::Generator(def_id, ..) => {
139 if self.def_id_visitor.visit_def_id(def_id, "type", &ty) {
142 if self.def_id_visitor.shallow() {
145 // Default type visitor doesn't visit signatures of fn types.
146 // Something like `fn() -> Priv {my_func}` is considered a private type even if
147 // `my_func` is public, so we need to visit signatures.
148 if let ty::FnDef(..) = ty.sty {
149 if tcx.fn_sig(def_id).visit_with(self) {
153 // Inherent static methods don't have self type in substs.
154 // Something like `fn() {my_method}` type of the method
155 // `impl Pub<Priv> { pub fn my_method() {} }` is considered a private type,
156 // so we need to visit the self type additionally.
157 if let Some(assoc_item) = tcx.opt_associated_item(def_id) {
158 if let ty::ImplContainer(impl_def_id) = assoc_item.container {
159 if tcx.type_of(impl_def_id).visit_with(self) {
165 ty::Projection(proj) | ty::UnnormalizedProjection(proj) => {
166 if self.def_id_visitor.skip_assoc_tys() {
167 // Visitors searching for minimal visibility/reachability want to
168 // conservatively approximate associated types like `<Type as Trait>::Alias`
169 // as visible/reachable even if both `Type` and `Trait` are private.
170 // Ideally, associated types should be substituted in the same way as
171 // free type aliases, but this isn't done yet.
174 // This will also visit substs if necessary, so we don't need to recurse.
175 return self.visit_trait(proj.trait_ref(tcx));
177 ty::Dynamic(predicates, ..) => {
178 // All traits in the list are considered the "primary" part of the type
179 // and are visited by shallow visitors.
180 for predicate in *predicates.skip_binder() {
181 let trait_ref = match *predicate {
182 ty::ExistentialPredicate::Trait(trait_ref) => trait_ref,
183 ty::ExistentialPredicate::Projection(proj) => proj.trait_ref(tcx),
184 ty::ExistentialPredicate::AutoTrait(def_id) =>
185 ty::ExistentialTraitRef { def_id, substs: InternalSubsts::empty() },
187 let ty::ExistentialTraitRef { def_id, substs: _ } = trait_ref;
188 if self.def_id_visitor.visit_def_id(def_id, "trait", &trait_ref) {
193 ty::Opaque(def_id, ..) => {
194 // Skip repeated `Opaque`s to avoid infinite recursion.
195 if self.visited_opaque_tys.insert(def_id) {
196 // The intent is to treat `impl Trait1 + Trait2` identically to
197 // `dyn Trait1 + Trait2`. Therefore we ignore def-id of the opaque type itself
198 // (it either has no visibility, or its visibility is insignificant, like
199 // visibilities of type aliases) and recurse into predicates instead to go
200 // through the trait list (default type visitor doesn't visit those traits).
201 // All traits in the list are considered the "primary" part of the type
202 // and are visited by shallow visitors.
203 if self.visit_predicates(tcx.predicates_of(def_id)) {
208 // These types don't have their own def-ids (but may have subcomponents
209 // with def-ids that should be visited recursively).
210 ty::Bool | ty::Char | ty::Int(..) | ty::Uint(..) |
211 ty::Float(..) | ty::Str | ty::Never |
212 ty::Array(..) | ty::Slice(..) | ty::Tuple(..) |
213 ty::RawPtr(..) | ty::Ref(..) | ty::FnPtr(..) |
214 ty::Param(..) | ty::Error | ty::GeneratorWitness(..) => {}
215 ty::Bound(..) | ty::Placeholder(..) | ty::Infer(..) =>
216 bug!("unexpected type: {:?}", ty),
219 !self.def_id_visitor.shallow() && ty.super_visit_with(self)
223 fn def_id_visibility<'tcx>(
226 ) -> (ty::Visibility, Span, &'static str) {
227 match tcx.hir().as_local_hir_id(def_id) {
229 let vis = match tcx.hir().get(hir_id) {
230 Node::Item(item) => &item.vis,
231 Node::ForeignItem(foreign_item) => &foreign_item.vis,
232 Node::TraitItem(..) | Node::Variant(..) => {
233 return def_id_visibility(tcx, tcx.hir().get_parent_did(hir_id));
235 Node::ImplItem(impl_item) => {
236 match tcx.hir().get(tcx.hir().get_parent_item(hir_id)) {
237 Node::Item(item) => match &item.node {
238 hir::ItemKind::Impl(.., None, _, _) => &impl_item.vis,
239 hir::ItemKind::Impl(.., Some(trait_ref), _, _)
240 => return def_id_visibility(tcx, trait_ref.path.res.def_id()),
241 kind => bug!("unexpected item kind: {:?}", kind),
243 node => bug!("unexpected node kind: {:?}", node),
246 Node::Ctor(vdata) => {
247 let parent_hir_id = tcx.hir().get_parent_node(hir_id);
248 match tcx.hir().get(parent_hir_id) {
249 Node::Variant(..) => {
250 let parent_did = tcx.hir().local_def_id(parent_hir_id);
251 let (mut ctor_vis, mut span, mut descr) = def_id_visibility(
255 let adt_def = tcx.adt_def(tcx.hir().get_parent_did(hir_id));
256 let ctor_did = tcx.hir().local_def_id(
257 vdata.ctor_hir_id().unwrap());
258 let variant = adt_def.variant_with_ctor_id(ctor_did);
260 if variant.is_field_list_non_exhaustive() &&
261 ctor_vis == ty::Visibility::Public
263 ctor_vis = ty::Visibility::Restricted(
264 DefId::local(CRATE_DEF_INDEX));
265 let attrs = tcx.get_attrs(variant.def_id);
266 span = attr::find_by_name(&attrs, sym::non_exhaustive)
268 descr = "crate-visible";
271 return (ctor_vis, span, descr);
274 let item = match tcx.hir().get(parent_hir_id) {
275 Node::Item(item) => item,
276 node => bug!("unexpected node kind: {:?}", node),
278 let (mut ctor_vis, mut span, mut descr) =
279 (ty::Visibility::from_hir(&item.vis, parent_hir_id, tcx),
280 item.vis.span, item.vis.node.descr());
281 for field in vdata.fields() {
282 let field_vis = ty::Visibility::from_hir(&field.vis, hir_id, tcx);
283 if ctor_vis.is_at_least(field_vis, tcx) {
284 ctor_vis = field_vis;
285 span = field.vis.span;
286 descr = field.vis.node.descr();
290 // If the structure is marked as non_exhaustive then lower the
291 // visibility to within the crate.
292 if ctor_vis == ty::Visibility::Public {
294 tcx.adt_def(tcx.hir().get_parent_did(hir_id));
295 if adt_def.non_enum_variant().is_field_list_non_exhaustive() {
297 ty::Visibility::Restricted(DefId::local(CRATE_DEF_INDEX));
298 span = attr::find_by_name(&item.attrs, sym::non_exhaustive)
300 descr = "crate-visible";
304 return (ctor_vis, span, descr);
306 node => bug!("unexpected node kind: {:?}", node),
309 Node::Expr(expr) => {
310 return (ty::Visibility::Restricted(
311 tcx.hir().get_module_parent(expr.hir_id)),
312 expr.span, "private")
314 node => bug!("unexpected node kind: {:?}", node)
316 (ty::Visibility::from_hir(vis, hir_id, tcx), vis.span, vis.node.descr())
319 let vis = tcx.visibility(def_id);
320 let descr = if vis == ty::Visibility::Public { "public" } else { "private" };
321 (vis, tcx.def_span(def_id), descr)
326 // Set the correct `TypeckTables` for the given `item_id` (or an empty table if
327 // there is no `TypeckTables` for the item).
328 fn item_tables<'a, 'tcx>(
331 empty_tables: &'a ty::TypeckTables<'tcx>,
332 ) -> &'a ty::TypeckTables<'tcx> {
333 let def_id = tcx.hir().local_def_id(hir_id);
334 if tcx.has_typeck_tables(def_id) { tcx.typeck_tables_of(def_id) } else { empty_tables }
337 fn min(vis1: ty::Visibility, vis2: ty::Visibility, tcx: TyCtxt<'_>) -> ty::Visibility {
338 if vis1.is_at_least(vis2, tcx) { vis2 } else { vis1 }
341 ////////////////////////////////////////////////////////////////////////////////
342 /// Visitor used to determine if pub(restricted) is used anywhere in the crate.
344 /// This is done so that `private_in_public` warnings can be turned into hard errors
345 /// in crates that have been updated to use pub(restricted).
346 ////////////////////////////////////////////////////////////////////////////////
347 struct PubRestrictedVisitor<'tcx> {
349 has_pub_restricted: bool,
352 impl Visitor<'tcx> for PubRestrictedVisitor<'tcx> {
353 fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> {
354 NestedVisitorMap::All(&self.tcx.hir())
356 fn visit_vis(&mut self, vis: &'tcx hir::Visibility) {
357 self.has_pub_restricted = self.has_pub_restricted || vis.node.is_pub_restricted();
361 ////////////////////////////////////////////////////////////////////////////////
362 /// Visitor used to determine impl visibility and reachability.
363 ////////////////////////////////////////////////////////////////////////////////
365 struct FindMin<'a, 'tcx, VL: VisibilityLike> {
367 access_levels: &'a AccessLevels,
371 impl<'a, 'tcx, VL: VisibilityLike> DefIdVisitor<'tcx> for FindMin<'a, 'tcx, VL> {
372 fn tcx(&self) -> TyCtxt<'tcx> { self.tcx }
373 fn shallow(&self) -> bool { VL::SHALLOW }
374 fn skip_assoc_tys(&self) -> bool { true }
375 fn visit_def_id(&mut self, def_id: DefId, _kind: &str, _descr: &dyn fmt::Display) -> bool {
376 self.min = VL::new_min(self, def_id);
381 trait VisibilityLike: Sized {
383 const SHALLOW: bool = false;
384 fn new_min(find: &FindMin<'_, '_, Self>, def_id: DefId) -> Self;
386 // Returns an over-approximation (`skip_assoc_tys` = true) of visibility due to
387 // associated types for which we can't determine visibility precisely.
391 access_levels: &AccessLevels,
393 let mut find = FindMin { tcx, access_levels, min: Self::MAX };
394 let def_id = tcx.hir().local_def_id(hir_id);
395 find.visit(tcx.type_of(def_id));
396 if let Some(trait_ref) = tcx.impl_trait_ref(def_id) {
397 find.visit_trait(trait_ref);
402 impl VisibilityLike for ty::Visibility {
403 const MAX: Self = ty::Visibility::Public;
404 fn new_min(find: &FindMin<'_, '_, Self>, def_id: DefId) -> Self {
405 min(def_id_visibility(find.tcx, def_id).0, find.min, find.tcx)
408 impl VisibilityLike for Option<AccessLevel> {
409 const MAX: Self = Some(AccessLevel::Public);
410 // Type inference is very smart sometimes.
411 // It can make an impl reachable even some components of its type or trait are unreachable.
412 // E.g. methods of `impl ReachableTrait<UnreachableTy> for ReachableTy<UnreachableTy> { ... }`
413 // can be usable from other crates (#57264). So we skip substs when calculating reachability
414 // and consider an impl reachable if its "shallow" type and trait are reachable.
416 // The assumption we make here is that type-inference won't let you use an impl without knowing
417 // both "shallow" version of its self type and "shallow" version of its trait if it exists
418 // (which require reaching the `DefId`s in them).
419 const SHALLOW: bool = true;
420 fn new_min(find: &FindMin<'_, '_, Self>, def_id: DefId) -> Self {
421 cmp::min(if let Some(hir_id) = find.tcx.hir().as_local_hir_id(def_id) {
422 find.access_levels.map.get(&hir_id).cloned()
429 ////////////////////////////////////////////////////////////////////////////////
430 /// The embargo visitor, used to determine the exports of the AST.
431 ////////////////////////////////////////////////////////////////////////////////
433 struct EmbargoVisitor<'tcx> {
436 // Accessibility levels for reachable nodes.
437 access_levels: AccessLevels,
438 // Previous accessibility level; `None` means unreachable.
439 prev_level: Option<AccessLevel>,
440 // Has something changed in the level map?
444 struct ReachEverythingInTheInterfaceVisitor<'a, 'tcx> {
445 access_level: Option<AccessLevel>,
447 ev: &'a mut EmbargoVisitor<'tcx>,
450 impl EmbargoVisitor<'tcx> {
451 fn get(&self, id: hir::HirId) -> Option<AccessLevel> {
452 self.access_levels.map.get(&id).cloned()
455 // Updates node level and returns the updated level.
456 fn update(&mut self, id: hir::HirId, level: Option<AccessLevel>) -> Option<AccessLevel> {
457 let old_level = self.get(id);
458 // Accessibility levels can only grow.
459 if level > old_level {
460 self.access_levels.map.insert(id, level.unwrap());
471 access_level: Option<AccessLevel>,
472 ) -> ReachEverythingInTheInterfaceVisitor<'_, 'tcx> {
473 ReachEverythingInTheInterfaceVisitor {
474 access_level: cmp::min(access_level, Some(AccessLevel::Reachable)),
475 item_def_id: self.tcx.hir().local_def_id(item_id),
481 /// Given the path segments of a `ItemKind::Use`, then we need
482 /// to update the visibility of the intermediate use so that it isn't linted
483 /// by `unreachable_pub`.
485 /// This isn't trivial as `path.res` has the `DefId` of the eventual target
486 /// of the use statement not of the next intermediate use statement.
488 /// To do this, consider the last two segments of the path to our intermediate
489 /// use statement. We expect the penultimate segment to be a module and the
490 /// last segment to be the name of the item we are exporting. We can then
491 /// look at the items contained in the module for the use statement with that
492 /// name and update that item's visibility.
494 /// FIXME: This solution won't work with glob imports and doesn't respect
495 /// namespaces. See <https://github.com/rust-lang/rust/pull/57922#discussion_r251234202>.
496 fn update_visibility_of_intermediate_use_statements(&mut self, segments: &[hir::PathSegment]) {
497 if let Some([module, segment]) = segments.rchunks_exact(2).next() {
498 if let Some(item) = module.res
499 .and_then(|res| res.mod_def_id())
500 .and_then(|def_id| self.tcx.hir().as_local_hir_id(def_id))
501 .map(|module_hir_id| self.tcx.hir().expect_item(module_hir_id))
503 if let hir::ItemKind::Mod(m) = &item.node {
504 for item_id in m.item_ids.as_ref() {
505 let item = self.tcx.hir().expect_item(item_id.id);
506 let def_id = self.tcx.hir().local_def_id(item_id.id);
507 if !self.tcx.hygienic_eq(segment.ident, item.ident, def_id) { continue; }
508 if let hir::ItemKind::Use(..) = item.node {
509 self.update(item.hir_id, Some(AccessLevel::Exported));
518 impl Visitor<'tcx> for EmbargoVisitor<'tcx> {
519 /// We want to visit items in the context of their containing
520 /// module and so forth, so supply a crate for doing a deep walk.
521 fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> {
522 NestedVisitorMap::All(&self.tcx.hir())
525 fn visit_item(&mut self, item: &'tcx hir::Item) {
526 let inherited_item_level = match item.node {
527 hir::ItemKind::Impl(..) =>
528 Option::<AccessLevel>::of_impl(item.hir_id, self.tcx, &self.access_levels),
529 // Foreign modules inherit level from parents.
530 hir::ItemKind::ForeignMod(..) => self.prev_level,
531 // Other `pub` items inherit levels from parents.
532 hir::ItemKind::Const(..) | hir::ItemKind::Enum(..) | hir::ItemKind::ExternCrate(..) |
533 hir::ItemKind::GlobalAsm(..) | hir::ItemKind::Fn(..) | hir::ItemKind::Mod(..) |
534 hir::ItemKind::Static(..) | hir::ItemKind::Struct(..) |
535 hir::ItemKind::Trait(..) | hir::ItemKind::TraitAlias(..) |
536 hir::ItemKind::Existential(..) |
537 hir::ItemKind::Ty(..) | hir::ItemKind::Union(..) | hir::ItemKind::Use(..) => {
538 if item.vis.node.is_pub() { self.prev_level } else { None }
542 // Update level of the item itself.
543 let item_level = self.update(item.hir_id, inherited_item_level);
545 // Update levels of nested things.
547 hir::ItemKind::Enum(ref def, _) => {
548 for variant in &def.variants {
549 let variant_level = self.update(variant.node.id, item_level);
550 if let Some(ctor_hir_id) = variant.node.data.ctor_hir_id() {
551 self.update(ctor_hir_id, item_level);
553 for field in variant.node.data.fields() {
554 self.update(field.hir_id, variant_level);
558 hir::ItemKind::Impl(.., ref trait_ref, _, ref impl_item_refs) => {
559 for impl_item_ref in impl_item_refs {
560 if trait_ref.is_some() || impl_item_ref.vis.node.is_pub() {
561 self.update(impl_item_ref.id.hir_id, item_level);
565 hir::ItemKind::Trait(.., ref trait_item_refs) => {
566 for trait_item_ref in trait_item_refs {
567 self.update(trait_item_ref.id.hir_id, item_level);
570 hir::ItemKind::Struct(ref def, _) | hir::ItemKind::Union(ref def, _) => {
571 if let Some(ctor_hir_id) = def.ctor_hir_id() {
572 self.update(ctor_hir_id, item_level);
574 for field in def.fields() {
575 if field.vis.node.is_pub() {
576 self.update(field.hir_id, item_level);
580 hir::ItemKind::ForeignMod(ref foreign_mod) => {
581 for foreign_item in &foreign_mod.items {
582 if foreign_item.vis.node.is_pub() {
583 self.update(foreign_item.hir_id, item_level);
587 hir::ItemKind::Existential(..) |
588 hir::ItemKind::Use(..) |
589 hir::ItemKind::Static(..) |
590 hir::ItemKind::Const(..) |
591 hir::ItemKind::GlobalAsm(..) |
592 hir::ItemKind::Ty(..) |
593 hir::ItemKind::Mod(..) |
594 hir::ItemKind::TraitAlias(..) |
595 hir::ItemKind::Fn(..) |
596 hir::ItemKind::ExternCrate(..) => {}
599 // Mark all items in interfaces of reachable items as reachable.
601 // The interface is empty.
602 hir::ItemKind::ExternCrate(..) => {}
603 // All nested items are checked by `visit_item`.
604 hir::ItemKind::Mod(..) => {}
605 // Re-exports are handled in `visit_mod`. However, in order to avoid looping over
606 // all of the items of a mod in `visit_mod` looking for use statements, we handle
607 // making sure that intermediate use statements have their visibilities updated here.
608 hir::ItemKind::Use(ref path, _) => {
609 if item_level.is_some() {
610 self.update_visibility_of_intermediate_use_statements(path.segments.as_ref());
613 // The interface is empty.
614 hir::ItemKind::GlobalAsm(..) => {}
615 hir::ItemKind::Existential(..) => {
616 // FIXME: This is some serious pessimization intended to workaround deficiencies
617 // in the reachability pass (`middle/reachable.rs`). Types are marked as link-time
618 // reachable if they are returned via `impl Trait`, even from private functions.
619 let exist_level = cmp::max(item_level, Some(AccessLevel::ReachableFromImplTrait));
620 self.reach(item.hir_id, exist_level).generics().predicates().ty();
623 hir::ItemKind::Const(..) | hir::ItemKind::Static(..) |
624 hir::ItemKind::Fn(..) | hir::ItemKind::Ty(..) => {
625 if item_level.is_some() {
626 self.reach(item.hir_id, item_level).generics().predicates().ty();
629 hir::ItemKind::Trait(.., ref trait_item_refs) => {
630 if item_level.is_some() {
631 self.reach(item.hir_id, item_level).generics().predicates();
633 for trait_item_ref in trait_item_refs {
634 let mut reach = self.reach(trait_item_ref.id.hir_id, item_level);
635 reach.generics().predicates();
637 if trait_item_ref.kind == AssocItemKind::Type &&
638 !trait_item_ref.defaultness.has_value() {
646 hir::ItemKind::TraitAlias(..) => {
647 if item_level.is_some() {
648 self.reach(item.hir_id, item_level).generics().predicates();
651 // Visit everything except for private impl items.
652 hir::ItemKind::Impl(.., ref impl_item_refs) => {
653 if item_level.is_some() {
654 self.reach(item.hir_id, item_level).generics().predicates().ty().trait_ref();
656 for impl_item_ref in impl_item_refs {
657 let impl_item_level = self.get(impl_item_ref.id.hir_id);
658 if impl_item_level.is_some() {
659 self.reach(impl_item_ref.id.hir_id, impl_item_level)
660 .generics().predicates().ty();
666 // Visit everything, but enum variants have their own levels.
667 hir::ItemKind::Enum(ref def, _) => {
668 if item_level.is_some() {
669 self.reach(item.hir_id, item_level).generics().predicates();
671 for variant in &def.variants {
672 let variant_level = self.get(variant.node.id);
673 if variant_level.is_some() {
674 for field in variant.node.data.fields() {
675 self.reach(field.hir_id, variant_level).ty();
677 // Corner case: if the variant is reachable, but its
678 // enum is not, make the enum reachable as well.
679 self.update(item.hir_id, variant_level);
683 // Visit everything, but foreign items have their own levels.
684 hir::ItemKind::ForeignMod(ref foreign_mod) => {
685 for foreign_item in &foreign_mod.items {
686 let foreign_item_level = self.get(foreign_item.hir_id);
687 if foreign_item_level.is_some() {
688 self.reach(foreign_item.hir_id, foreign_item_level)
689 .generics().predicates().ty();
693 // Visit everything except for private fields.
694 hir::ItemKind::Struct(ref struct_def, _) |
695 hir::ItemKind::Union(ref struct_def, _) => {
696 if item_level.is_some() {
697 self.reach(item.hir_id, item_level).generics().predicates();
698 for field in struct_def.fields() {
699 let field_level = self.get(field.hir_id);
700 if field_level.is_some() {
701 self.reach(field.hir_id, field_level).ty();
708 let orig_level = mem::replace(&mut self.prev_level, item_level);
709 intravisit::walk_item(self, item);
710 self.prev_level = orig_level;
713 fn visit_block(&mut self, b: &'tcx hir::Block) {
714 // Blocks can have public items, for example impls, but they always
715 // start as completely private regardless of publicity of a function,
716 // constant, type, field, etc., in which this block resides.
717 let orig_level = mem::replace(&mut self.prev_level, None);
718 intravisit::walk_block(self, b);
719 self.prev_level = orig_level;
722 fn visit_mod(&mut self, m: &'tcx hir::Mod, _sp: Span, id: hir::HirId) {
723 // This code is here instead of in visit_item so that the
724 // crate module gets processed as well.
725 if self.prev_level.is_some() {
726 let def_id = self.tcx.hir().local_def_id(id);
727 if let Some(exports) = self.tcx.module_exports(def_id) {
728 for export in exports.iter() {
729 if export.vis == ty::Visibility::Public {
730 if let Some(def_id) = export.res.opt_def_id() {
731 if let Some(hir_id) = self.tcx.hir().as_local_hir_id(def_id) {
732 self.update(hir_id, Some(AccessLevel::Exported));
740 intravisit::walk_mod(self, m, id);
743 fn visit_macro_def(&mut self, md: &'tcx hir::MacroDef) {
744 if attr::find_transparency(&md.attrs, md.legacy).0 != Transparency::Opaque {
745 self.update(md.hir_id, Some(AccessLevel::Public));
749 let module_did = ty::DefIdTree::parent(
751 self.tcx.hir().local_def_id(md.hir_id)
753 let mut module_id = self.tcx.hir().as_local_hir_id(module_did).unwrap();
754 let level = if md.vis.node.is_pub() { self.get(module_id) } else { None };
755 let level = self.update(md.hir_id, level);
761 let module = if module_id == hir::CRATE_HIR_ID {
762 &self.tcx.hir().krate().module
763 } else if let hir::ItemKind::Mod(ref module) =
764 self.tcx.hir().expect_item(module_id).node {
769 for id in &module.item_ids {
770 self.update(id.id, level);
772 let def_id = self.tcx.hir().local_def_id(module_id);
773 if let Some(exports) = self.tcx.module_exports(def_id) {
774 for export in exports.iter() {
775 if let Some(hir_id) = self.tcx.hir().as_local_hir_id(export.res.def_id()) {
776 self.update(hir_id, level);
781 if module_id == hir::CRATE_HIR_ID {
784 module_id = self.tcx.hir().get_parent_node(module_id);
789 impl ReachEverythingInTheInterfaceVisitor<'_, 'tcx> {
790 fn generics(&mut self) -> &mut Self {
791 for param in &self.ev.tcx.generics_of(self.item_def_id).params {
793 GenericParamDefKind::Lifetime => {}
794 GenericParamDefKind::Type { has_default, .. } => {
796 self.visit(self.ev.tcx.type_of(param.def_id));
799 GenericParamDefKind::Const => {
800 self.visit(self.ev.tcx.type_of(param.def_id));
807 fn predicates(&mut self) -> &mut Self {
808 self.visit_predicates(self.ev.tcx.predicates_of(self.item_def_id));
812 fn ty(&mut self) -> &mut Self {
813 self.visit(self.ev.tcx.type_of(self.item_def_id));
817 fn trait_ref(&mut self) -> &mut Self {
818 if let Some(trait_ref) = self.ev.tcx.impl_trait_ref(self.item_def_id) {
819 self.visit_trait(trait_ref);
825 impl DefIdVisitor<'tcx> for ReachEverythingInTheInterfaceVisitor<'_, 'tcx> {
826 fn tcx(&self) -> TyCtxt<'tcx> { self.ev.tcx }
827 fn visit_def_id(&mut self, def_id: DefId, _kind: &str, _descr: &dyn fmt::Display) -> bool {
828 if let Some(hir_id) = self.ev.tcx.hir().as_local_hir_id(def_id) {
829 self.ev.update(hir_id, self.access_level);
835 //////////////////////////////////////////////////////////////////////////////////////
836 /// Name privacy visitor, checks privacy and reports violations.
837 /// Most of name privacy checks are performed during the main resolution phase,
838 /// or later in type checking when field accesses and associated items are resolved.
839 /// This pass performs remaining checks for fields in struct expressions and patterns.
840 //////////////////////////////////////////////////////////////////////////////////////
842 struct NamePrivacyVisitor<'a, 'tcx> {
844 tables: &'a ty::TypeckTables<'tcx>,
845 current_item: hir::HirId,
846 empty_tables: &'a ty::TypeckTables<'tcx>,
849 impl<'a, 'tcx> NamePrivacyVisitor<'a, 'tcx> {
850 // Checks that a field in a struct constructor (expression or pattern) is accessible.
851 fn check_field(&mut self,
852 use_ctxt: Span, // syntax context of the field name at the use site
853 span: Span, // span of the field pattern, e.g., `x: 0`
854 def: &'tcx ty::AdtDef, // definition of the struct or enum
855 field: &'tcx ty::FieldDef) { // definition of the field
856 let ident = Ident::new(kw::Invalid, use_ctxt);
857 let current_hir = self.current_item;
858 let def_id = self.tcx.adjust_ident_and_get_scope(ident, def.did, current_hir).1;
859 if !def.is_enum() && !field.vis.is_accessible_from(def_id, self.tcx) {
860 struct_span_err!(self.tcx.sess, span, E0451, "field `{}` of {} `{}` is private",
861 field.ident, def.variant_descr(), self.tcx.def_path_str(def.did))
862 .span_label(span, format!("field `{}` is private", field.ident))
868 impl<'a, 'tcx> Visitor<'tcx> for NamePrivacyVisitor<'a, 'tcx> {
869 /// We want to visit items in the context of their containing
870 /// module and so forth, so supply a crate for doing a deep walk.
871 fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> {
872 NestedVisitorMap::All(&self.tcx.hir())
875 fn visit_mod(&mut self, _m: &'tcx hir::Mod, _s: Span, _n: hir::HirId) {
876 // Don't visit nested modules, since we run a separate visitor walk
877 // for each module in `privacy_access_levels`
880 fn visit_nested_body(&mut self, body: hir::BodyId) {
881 let orig_tables = mem::replace(&mut self.tables, self.tcx.body_tables(body));
882 let body = self.tcx.hir().body(body);
883 self.visit_body(body);
884 self.tables = orig_tables;
887 fn visit_item(&mut self, item: &'tcx hir::Item) {
888 let orig_current_item = mem::replace(&mut self.current_item, item.hir_id);
890 mem::replace(&mut self.tables, item_tables(self.tcx, item.hir_id, self.empty_tables));
891 intravisit::walk_item(self, item);
892 self.current_item = orig_current_item;
893 self.tables = orig_tables;
896 fn visit_trait_item(&mut self, ti: &'tcx hir::TraitItem) {
898 mem::replace(&mut self.tables, item_tables(self.tcx, ti.hir_id, self.empty_tables));
899 intravisit::walk_trait_item(self, ti);
900 self.tables = orig_tables;
903 fn visit_impl_item(&mut self, ii: &'tcx hir::ImplItem) {
905 mem::replace(&mut self.tables, item_tables(self.tcx, ii.hir_id, self.empty_tables));
906 intravisit::walk_impl_item(self, ii);
907 self.tables = orig_tables;
910 fn visit_expr(&mut self, expr: &'tcx hir::Expr) {
912 hir::ExprKind::Struct(ref qpath, ref fields, ref base) => {
913 let res = self.tables.qpath_res(qpath, expr.hir_id);
914 let adt = self.tables.expr_ty(expr).ty_adt_def().unwrap();
915 let variant = adt.variant_of_res(res);
916 if let Some(ref base) = *base {
917 // If the expression uses FRU we need to make sure all the unmentioned fields
918 // are checked for privacy (RFC 736). Rather than computing the set of
919 // unmentioned fields, just check them all.
920 for (vf_index, variant_field) in variant.fields.iter().enumerate() {
921 let field = fields.iter().find(|f| {
922 self.tcx.field_index(f.hir_id, self.tables) == vf_index
924 let (use_ctxt, span) = match field {
925 Some(field) => (field.ident.span, field.span),
926 None => (base.span, base.span),
928 self.check_field(use_ctxt, span, adt, variant_field);
931 for field in fields {
932 let use_ctxt = field.ident.span;
933 let index = self.tcx.field_index(field.hir_id, self.tables);
934 self.check_field(use_ctxt, field.span, adt, &variant.fields[index]);
941 intravisit::walk_expr(self, expr);
944 fn visit_pat(&mut self, pat: &'tcx hir::Pat) {
946 PatKind::Struct(ref qpath, ref fields, _) => {
947 let res = self.tables.qpath_res(qpath, pat.hir_id);
948 let adt = self.tables.pat_ty(pat).ty_adt_def().unwrap();
949 let variant = adt.variant_of_res(res);
950 for field in fields {
951 let use_ctxt = field.node.ident.span;
952 let index = self.tcx.field_index(field.node.hir_id, self.tables);
953 self.check_field(use_ctxt, field.span, adt, &variant.fields[index]);
959 intravisit::walk_pat(self, pat);
963 ////////////////////////////////////////////////////////////////////////////////////////////
964 /// Type privacy visitor, checks types for privacy and reports violations.
965 /// Both explicitly written types and inferred types of expressions and patters are checked.
966 /// Checks are performed on "semantic" types regardless of names and their hygiene.
967 ////////////////////////////////////////////////////////////////////////////////////////////
969 struct TypePrivacyVisitor<'a, 'tcx> {
971 tables: &'a ty::TypeckTables<'tcx>,
975 empty_tables: &'a ty::TypeckTables<'tcx>,
978 impl<'a, 'tcx> TypePrivacyVisitor<'a, 'tcx> {
979 fn item_is_accessible(&self, did: DefId) -> bool {
980 def_id_visibility(self.tcx, did).0.is_accessible_from(self.current_item, self.tcx)
983 // Take node-id of an expression or pattern and check its type for privacy.
984 fn check_expr_pat_type(&mut self, id: hir::HirId, span: Span) -> bool {
986 if self.visit(self.tables.node_type(id)) || self.visit(self.tables.node_substs(id)) {
989 if let Some(adjustments) = self.tables.adjustments().get(id) {
990 for adjustment in adjustments {
991 if self.visit(adjustment.target) {
999 fn check_def_id(&mut self, def_id: DefId, kind: &str, descr: &dyn fmt::Display) -> bool {
1000 let is_error = !self.item_is_accessible(def_id);
1002 self.tcx.sess.span_err(self.span, &format!("{} `{}` is private", kind, descr));
1008 impl<'a, 'tcx> Visitor<'tcx> for TypePrivacyVisitor<'a, 'tcx> {
1009 /// We want to visit items in the context of their containing
1010 /// module and so forth, so supply a crate for doing a deep walk.
1011 fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> {
1012 NestedVisitorMap::All(&self.tcx.hir())
1015 fn visit_mod(&mut self, _m: &'tcx hir::Mod, _s: Span, _n: hir::HirId) {
1016 // Don't visit nested modules, since we run a separate visitor walk
1017 // for each module in `privacy_access_levels`
1020 fn visit_nested_body(&mut self, body: hir::BodyId) {
1021 let orig_tables = mem::replace(&mut self.tables, self.tcx.body_tables(body));
1022 let orig_in_body = mem::replace(&mut self.in_body, true);
1023 let body = self.tcx.hir().body(body);
1024 self.visit_body(body);
1025 self.tables = orig_tables;
1026 self.in_body = orig_in_body;
1029 fn visit_ty(&mut self, hir_ty: &'tcx hir::Ty) {
1030 self.span = hir_ty.span;
1033 if self.visit(self.tables.node_type(hir_ty.hir_id)) {
1037 // Types in signatures.
1038 // FIXME: This is very ineffective. Ideally each HIR type should be converted
1039 // into a semantic type only once and the result should be cached somehow.
1040 if self.visit(rustc_typeck::hir_ty_to_ty(self.tcx, hir_ty)) {
1045 intravisit::walk_ty(self, hir_ty);
1048 fn visit_trait_ref(&mut self, trait_ref: &'tcx hir::TraitRef) {
1049 self.span = trait_ref.path.span;
1051 // Avoid calling `hir_trait_to_predicates` in bodies, it will ICE.
1052 // The traits' privacy in bodies is already checked as a part of trait object types.
1053 let (principal, bounds) = rustc_typeck::hir_trait_to_predicates(self.tcx, trait_ref);
1054 if self.visit_trait(*principal.skip_binder()) {
1057 for (poly_predicate, _) in bounds.projection_bounds {
1059 if self.visit(poly_predicate.skip_binder().ty) ||
1060 self.visit_trait(poly_predicate.skip_binder().projection_ty.trait_ref(tcx)) {
1066 intravisit::walk_trait_ref(self, trait_ref);
1069 // Check types of expressions
1070 fn visit_expr(&mut self, expr: &'tcx hir::Expr) {
1071 if self.check_expr_pat_type(expr.hir_id, expr.span) {
1072 // Do not check nested expressions if the error already happened.
1076 hir::ExprKind::Assign(.., ref rhs) | hir::ExprKind::Match(ref rhs, ..) => {
1077 // Do not report duplicate errors for `x = y` and `match x { ... }`.
1078 if self.check_expr_pat_type(rhs.hir_id, rhs.span) {
1082 hir::ExprKind::MethodCall(_, span, _) => {
1083 // Method calls have to be checked specially.
1085 if let Some(def_id) = self.tables.type_dependent_def_id(expr.hir_id) {
1086 if self.visit(self.tcx.type_of(def_id)) {
1090 self.tcx.sess.delay_span_bug(expr.span,
1091 "no type-dependent def for method call");
1097 intravisit::walk_expr(self, expr);
1100 // Prohibit access to associated items with insufficient nominal visibility.
1102 // Additionally, until better reachability analysis for macros 2.0 is available,
1103 // we prohibit access to private statics from other crates, this allows to give
1104 // more code internal visibility at link time. (Access to private functions
1105 // is already prohibited by type privacy for function types.)
1106 fn visit_qpath(&mut self, qpath: &'tcx hir::QPath, id: hir::HirId, span: Span) {
1107 let def = match self.tables.qpath_res(qpath, id) {
1108 Res::Def(kind, def_id) => Some((kind, def_id)),
1111 let def = def.filter(|(kind, _)| {
1114 | DefKind::AssocConst
1116 | DefKind::AssocExistential
1117 | DefKind::Static => true,
1121 if let Some((kind, def_id)) = def {
1122 let is_local_static = if let DefKind::Static = kind {
1125 if !self.item_is_accessible(def_id) && !is_local_static {
1126 let name = match *qpath {
1127 hir::QPath::Resolved(_, ref path) => path.to_string(),
1128 hir::QPath::TypeRelative(_, ref segment) => segment.ident.to_string(),
1130 let msg = format!("{} `{}` is private", kind.descr(), name);
1131 self.tcx.sess.span_err(span, &msg);
1136 intravisit::walk_qpath(self, qpath, id, span);
1139 // Check types of patterns.
1140 fn visit_pat(&mut self, pattern: &'tcx hir::Pat) {
1141 if self.check_expr_pat_type(pattern.hir_id, pattern.span) {
1142 // Do not check nested patterns if the error already happened.
1146 intravisit::walk_pat(self, pattern);
1149 fn visit_local(&mut self, local: &'tcx hir::Local) {
1150 if let Some(ref init) = local.init {
1151 if self.check_expr_pat_type(init.hir_id, init.span) {
1152 // Do not report duplicate errors for `let x = y`.
1157 intravisit::walk_local(self, local);
1160 // Check types in item interfaces.
1161 fn visit_item(&mut self, item: &'tcx hir::Item) {
1162 let orig_current_item = mem::replace(&mut self.current_item,
1163 self.tcx.hir().local_def_id(item.hir_id));
1164 let orig_in_body = mem::replace(&mut self.in_body, false);
1166 mem::replace(&mut self.tables, item_tables(self.tcx, item.hir_id, self.empty_tables));
1167 intravisit::walk_item(self, item);
1168 self.tables = orig_tables;
1169 self.in_body = orig_in_body;
1170 self.current_item = orig_current_item;
1173 fn visit_trait_item(&mut self, ti: &'tcx hir::TraitItem) {
1175 mem::replace(&mut self.tables, item_tables(self.tcx, ti.hir_id, self.empty_tables));
1176 intravisit::walk_trait_item(self, ti);
1177 self.tables = orig_tables;
1180 fn visit_impl_item(&mut self, ii: &'tcx hir::ImplItem) {
1182 mem::replace(&mut self.tables, item_tables(self.tcx, ii.hir_id, self.empty_tables));
1183 intravisit::walk_impl_item(self, ii);
1184 self.tables = orig_tables;
1188 impl DefIdVisitor<'tcx> for TypePrivacyVisitor<'a, 'tcx> {
1189 fn tcx(&self) -> TyCtxt<'tcx> { self.tcx }
1190 fn visit_def_id(&mut self, def_id: DefId, kind: &str, descr: &dyn fmt::Display) -> bool {
1191 self.check_def_id(def_id, kind, descr)
1195 ///////////////////////////////////////////////////////////////////////////////
1196 /// Obsolete visitors for checking for private items in public interfaces.
1197 /// These visitors are supposed to be kept in frozen state and produce an
1198 /// "old error node set". For backward compatibility the new visitor reports
1199 /// warnings instead of hard errors when the erroneous node is not in this old set.
1200 ///////////////////////////////////////////////////////////////////////////////
1202 struct ObsoleteVisiblePrivateTypesVisitor<'a, 'tcx> {
1204 access_levels: &'a AccessLevels,
1206 // Set of errors produced by this obsolete visitor.
1207 old_error_set: HirIdSet,
1210 struct ObsoleteCheckTypeForPrivatenessVisitor<'a, 'b, 'tcx> {
1211 inner: &'a ObsoleteVisiblePrivateTypesVisitor<'b, 'tcx>,
1212 /// Whether the type refers to private types.
1213 contains_private: bool,
1214 /// Whether we've recurred at all (i.e., if we're pointing at the
1215 /// first type on which `visit_ty` was called).
1216 at_outer_type: bool,
1217 /// Whether that first type is a public path.
1218 outer_type_is_public_path: bool,
1221 impl<'a, 'tcx> ObsoleteVisiblePrivateTypesVisitor<'a, 'tcx> {
1222 fn path_is_private_type(&self, path: &hir::Path) -> bool {
1223 let did = match path.res {
1224 Res::PrimTy(..) | Res::SelfTy(..) | Res::Err => return false,
1225 res => res.def_id(),
1228 // A path can only be private if:
1229 // it's in this crate...
1230 if let Some(hir_id) = self.tcx.hir().as_local_hir_id(did) {
1231 // .. and it corresponds to a private type in the AST (this returns
1232 // `None` for type parameters).
1233 match self.tcx.hir().find(hir_id) {
1234 Some(Node::Item(ref item)) => !item.vis.node.is_pub(),
1235 Some(_) | None => false,
1242 fn trait_is_public(&self, trait_id: hir::HirId) -> bool {
1243 // FIXME: this would preferably be using `exported_items`, but all
1244 // traits are exported currently (see `EmbargoVisitor.exported_trait`).
1245 self.access_levels.is_public(trait_id)
1248 fn check_generic_bound(&mut self, bound: &hir::GenericBound) {
1249 if let hir::GenericBound::Trait(ref trait_ref, _) = *bound {
1250 if self.path_is_private_type(&trait_ref.trait_ref.path) {
1251 self.old_error_set.insert(trait_ref.trait_ref.hir_ref_id);
1256 fn item_is_public(&self, id: &hir::HirId, vis: &hir::Visibility) -> bool {
1257 self.access_levels.is_reachable(*id) || vis.node.is_pub()
1261 impl<'a, 'b, 'tcx, 'v> Visitor<'v> for ObsoleteCheckTypeForPrivatenessVisitor<'a, 'b, 'tcx> {
1262 fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'v> {
1263 NestedVisitorMap::None
1266 fn visit_ty(&mut self, ty: &hir::Ty) {
1267 if let hir::TyKind::Path(hir::QPath::Resolved(_, ref path)) = ty.node {
1268 if self.inner.path_is_private_type(path) {
1269 self.contains_private = true;
1270 // Found what we're looking for, so let's stop working.
1274 if let hir::TyKind::Path(_) = ty.node {
1275 if self.at_outer_type {
1276 self.outer_type_is_public_path = true;
1279 self.at_outer_type = false;
1280 intravisit::walk_ty(self, ty)
1283 // Don't want to recurse into `[, .. expr]`.
1284 fn visit_expr(&mut self, _: &hir::Expr) {}
1287 impl<'a, 'tcx> Visitor<'tcx> for ObsoleteVisiblePrivateTypesVisitor<'a, 'tcx> {
1288 /// We want to visit items in the context of their containing
1289 /// module and so forth, so supply a crate for doing a deep walk.
1290 fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> {
1291 NestedVisitorMap::All(&self.tcx.hir())
1294 fn visit_item(&mut self, item: &'tcx hir::Item) {
1296 // Contents of a private mod can be re-exported, so we need
1297 // to check internals.
1298 hir::ItemKind::Mod(_) => {}
1300 // An `extern {}` doesn't introduce a new privacy
1301 // namespace (the contents have their own privacies).
1302 hir::ItemKind::ForeignMod(_) => {}
1304 hir::ItemKind::Trait(.., ref bounds, _) => {
1305 if !self.trait_is_public(item.hir_id) {
1309 for bound in bounds.iter() {
1310 self.check_generic_bound(bound)
1314 // Impls need some special handling to try to offer useful
1315 // error messages without (too many) false positives
1316 // (i.e., we could just return here to not check them at
1317 // all, or some worse estimation of whether an impl is
1318 // publicly visible).
1319 hir::ItemKind::Impl(.., ref g, ref trait_ref, ref self_, ref impl_item_refs) => {
1320 // `impl [... for] Private` is never visible.
1321 let self_contains_private;
1322 // `impl [... for] Public<...>`, but not `impl [... for]
1323 // Vec<Public>` or `(Public,)`, etc.
1324 let self_is_public_path;
1326 // Check the properties of the `Self` type:
1328 let mut visitor = ObsoleteCheckTypeForPrivatenessVisitor {
1330 contains_private: false,
1331 at_outer_type: true,
1332 outer_type_is_public_path: false,
1334 visitor.visit_ty(&self_);
1335 self_contains_private = visitor.contains_private;
1336 self_is_public_path = visitor.outer_type_is_public_path;
1339 // Miscellaneous info about the impl:
1341 // `true` iff this is `impl Private for ...`.
1342 let not_private_trait =
1343 trait_ref.as_ref().map_or(true, // no trait counts as public trait
1345 let did = tr.path.res.def_id();
1347 if let Some(hir_id) = self.tcx.hir().as_local_hir_id(did) {
1348 self.trait_is_public(hir_id)
1350 true // external traits must be public
1354 // `true` iff this is a trait impl or at least one method is public.
1356 // `impl Public { $( fn ...() {} )* }` is not visible.
1358 // This is required over just using the methods' privacy
1359 // directly because we might have `impl<T: Foo<Private>> ...`,
1360 // and we shouldn't warn about the generics if all the methods
1361 // are private (because `T` won't be visible externally).
1362 let trait_or_some_public_method =
1363 trait_ref.is_some() ||
1364 impl_item_refs.iter()
1365 .any(|impl_item_ref| {
1366 let impl_item = self.tcx.hir().impl_item(impl_item_ref.id);
1367 match impl_item.node {
1368 hir::ImplItemKind::Const(..) |
1369 hir::ImplItemKind::Method(..) => {
1370 self.access_levels.is_reachable(
1371 impl_item_ref.id.hir_id)
1373 hir::ImplItemKind::Existential(..) |
1374 hir::ImplItemKind::Type(_) => false,
1378 if !self_contains_private &&
1379 not_private_trait &&
1380 trait_or_some_public_method {
1382 intravisit::walk_generics(self, g);
1386 for impl_item_ref in impl_item_refs {
1387 // This is where we choose whether to walk down
1388 // further into the impl to check its items. We
1389 // should only walk into public items so that we
1390 // don't erroneously report errors for private
1391 // types in private items.
1392 let impl_item = self.tcx.hir().impl_item(impl_item_ref.id);
1393 match impl_item.node {
1394 hir::ImplItemKind::Const(..) |
1395 hir::ImplItemKind::Method(..)
1396 if self.item_is_public(&impl_item.hir_id, &impl_item.vis) =>
1398 intravisit::walk_impl_item(self, impl_item)
1400 hir::ImplItemKind::Type(..) => {
1401 intravisit::walk_impl_item(self, impl_item)
1408 // Any private types in a trait impl fall into three
1410 // 1. mentioned in the trait definition
1411 // 2. mentioned in the type params/generics
1412 // 3. mentioned in the associated types of the impl
1414 // Those in 1. can only occur if the trait is in
1415 // this crate and will've been warned about on the
1416 // trait definition (there's no need to warn twice
1417 // so we don't check the methods).
1419 // Those in 2. are warned via walk_generics and this
1421 intravisit::walk_path(self, &tr.path);
1423 // Those in 3. are warned with this call.
1424 for impl_item_ref in impl_item_refs {
1425 let impl_item = self.tcx.hir().impl_item(impl_item_ref.id);
1426 if let hir::ImplItemKind::Type(ref ty) = impl_item.node {
1432 } else if trait_ref.is_none() && self_is_public_path {
1433 // `impl Public<Private> { ... }`. Any public static
1434 // methods will be visible as `Public::foo`.
1435 let mut found_pub_static = false;
1436 for impl_item_ref in impl_item_refs {
1437 if self.item_is_public(&impl_item_ref.id.hir_id, &impl_item_ref.vis) {
1438 let impl_item = self.tcx.hir().impl_item(impl_item_ref.id);
1439 match impl_item_ref.kind {
1440 AssocItemKind::Const => {
1441 found_pub_static = true;
1442 intravisit::walk_impl_item(self, impl_item);
1444 AssocItemKind::Method { has_self: false } => {
1445 found_pub_static = true;
1446 intravisit::walk_impl_item(self, impl_item);
1452 if found_pub_static {
1453 intravisit::walk_generics(self, g)
1459 // `type ... = ...;` can contain private types, because
1460 // we're introducing a new name.
1461 hir::ItemKind::Ty(..) => return,
1463 // Not at all public, so we don't care.
1464 _ if !self.item_is_public(&item.hir_id, &item.vis) => {
1471 // We've carefully constructed it so that if we're here, then
1472 // any `visit_ty`'s will be called on things that are in
1473 // public signatures, i.e., things that we're interested in for
1475 intravisit::walk_item(self, item);
1478 fn visit_generics(&mut self, generics: &'tcx hir::Generics) {
1479 for param in &generics.params {
1480 for bound in ¶m.bounds {
1481 self.check_generic_bound(bound);
1484 for predicate in &generics.where_clause.predicates {
1486 hir::WherePredicate::BoundPredicate(bound_pred) => {
1487 for bound in bound_pred.bounds.iter() {
1488 self.check_generic_bound(bound)
1491 hir::WherePredicate::RegionPredicate(_) => {}
1492 hir::WherePredicate::EqPredicate(eq_pred) => {
1493 self.visit_ty(&eq_pred.rhs_ty);
1499 fn visit_foreign_item(&mut self, item: &'tcx hir::ForeignItem) {
1500 if self.access_levels.is_reachable(item.hir_id) {
1501 intravisit::walk_foreign_item(self, item)
1505 fn visit_ty(&mut self, t: &'tcx hir::Ty) {
1506 if let hir::TyKind::Path(hir::QPath::Resolved(_, ref path)) = t.node {
1507 if self.path_is_private_type(path) {
1508 self.old_error_set.insert(t.hir_id);
1511 intravisit::walk_ty(self, t)
1514 fn visit_variant(&mut self,
1515 v: &'tcx hir::Variant,
1516 g: &'tcx hir::Generics,
1517 item_id: hir::HirId) {
1518 if self.access_levels.is_reachable(v.node.id) {
1519 self.in_variant = true;
1520 intravisit::walk_variant(self, v, g, item_id);
1521 self.in_variant = false;
1525 fn visit_struct_field(&mut self, s: &'tcx hir::StructField) {
1526 if s.vis.node.is_pub() || self.in_variant {
1527 intravisit::walk_struct_field(self, s);
1531 // We don't need to introspect into these at all: an
1532 // expression/block context can't possibly contain exported things.
1533 // (Making them no-ops stops us from traversing the whole AST without
1534 // having to be super careful about our `walk_...` calls above.)
1535 fn visit_block(&mut self, _: &'tcx hir::Block) {}
1536 fn visit_expr(&mut self, _: &'tcx hir::Expr) {}
1539 ///////////////////////////////////////////////////////////////////////////////
1540 /// SearchInterfaceForPrivateItemsVisitor traverses an item's interface and
1541 /// finds any private components in it.
1542 /// PrivateItemsInPublicInterfacesVisitor ensures there are no private types
1543 /// and traits in public interfaces.
1544 ///////////////////////////////////////////////////////////////////////////////
1546 struct SearchInterfaceForPrivateItemsVisitor<'tcx> {
1548 item_id: hir::HirId,
1551 /// The visitor checks that each component type is at least this visible.
1552 required_visibility: ty::Visibility,
1553 has_pub_restricted: bool,
1554 has_old_errors: bool,
1558 impl SearchInterfaceForPrivateItemsVisitor<'tcx> {
1559 fn generics(&mut self) -> &mut Self {
1560 for param in &self.tcx.generics_of(self.item_def_id).params {
1562 GenericParamDefKind::Lifetime => {}
1563 GenericParamDefKind::Type { has_default, .. } => {
1565 self.visit(self.tcx.type_of(param.def_id));
1568 GenericParamDefKind::Const => {
1569 self.visit(self.tcx.type_of(param.def_id));
1576 fn predicates(&mut self) -> &mut Self {
1577 // N.B., we use `explicit_predicates_of` and not `predicates_of`
1578 // because we don't want to report privacy errors due to where
1579 // clauses that the compiler inferred. We only want to
1580 // consider the ones that the user wrote. This is important
1581 // for the inferred outlives rules; see
1582 // `src/test/ui/rfc-2093-infer-outlives/privacy.rs`.
1583 self.visit_predicates(self.tcx.explicit_predicates_of(self.item_def_id));
1587 fn ty(&mut self) -> &mut Self {
1588 self.visit(self.tcx.type_of(self.item_def_id));
1592 fn check_def_id(&mut self, def_id: DefId, kind: &str, descr: &dyn fmt::Display) -> bool {
1593 if self.leaks_private_dep(def_id) {
1594 self.tcx.lint_hir(lint::builtin::EXPORTED_PRIVATE_DEPENDENCIES,
1597 &format!("{} `{}` from private dependency '{}' in public \
1598 interface", kind, descr,
1599 self.tcx.crate_name(def_id.krate)));
1603 let hir_id = match self.tcx.hir().as_local_hir_id(def_id) {
1604 Some(hir_id) => hir_id,
1605 None => return false,
1608 let (vis, vis_span, vis_descr) = def_id_visibility(self.tcx, def_id);
1609 if !vis.is_at_least(self.required_visibility, self.tcx) {
1610 let msg = format!("{} {} `{}` in public interface", vis_descr, kind, descr);
1611 if self.has_pub_restricted || self.has_old_errors || self.in_assoc_ty {
1612 let mut err = if kind == "trait" {
1613 struct_span_err!(self.tcx.sess, self.span, E0445, "{}", msg)
1615 struct_span_err!(self.tcx.sess, self.span, E0446, "{}", msg)
1617 err.span_label(self.span, format!("can't leak {} {}", vis_descr, kind));
1618 err.span_label(vis_span, format!("`{}` declared as {}", descr, vis_descr));
1621 let err_code = if kind == "trait" { "E0445" } else { "E0446" };
1622 self.tcx.lint_hir(lint::builtin::PRIVATE_IN_PUBLIC, hir_id, self.span,
1623 &format!("{} (error {})", msg, err_code));
1631 /// An item is 'leaked' from a private dependency if all
1632 /// of the following are true:
1633 /// 1. It's contained within a public type
1634 /// 2. It comes from a private crate
1635 fn leaks_private_dep(&self, item_id: DefId) -> bool {
1636 let ret = self.required_visibility == ty::Visibility::Public &&
1637 self.tcx.is_private_dep(item_id.krate);
1639 log::debug!("leaks_private_dep(item_id={:?})={}", item_id, ret);
1644 impl DefIdVisitor<'tcx> for SearchInterfaceForPrivateItemsVisitor<'tcx> {
1645 fn tcx(&self) -> TyCtxt<'tcx> { self.tcx }
1646 fn visit_def_id(&mut self, def_id: DefId, kind: &str, descr: &dyn fmt::Display) -> bool {
1647 self.check_def_id(def_id, kind, descr)
1651 struct PrivateItemsInPublicInterfacesVisitor<'a, 'tcx> {
1653 has_pub_restricted: bool,
1654 old_error_set: &'a HirIdSet,
1657 impl<'a, 'tcx> PrivateItemsInPublicInterfacesVisitor<'a, 'tcx> {
1660 item_id: hir::HirId,
1661 required_visibility: ty::Visibility,
1662 ) -> SearchInterfaceForPrivateItemsVisitor<'tcx> {
1663 let mut has_old_errors = false;
1665 // Slow path taken only if there any errors in the crate.
1666 for &id in self.old_error_set {
1667 // Walk up the nodes until we find `item_id` (or we hit a root).
1671 has_old_errors = true;
1674 let parent = self.tcx.hir().get_parent_node(id);
1686 SearchInterfaceForPrivateItemsVisitor {
1689 item_def_id: self.tcx.hir().local_def_id(item_id),
1690 span: self.tcx.hir().span(item_id),
1691 required_visibility,
1692 has_pub_restricted: self.has_pub_restricted,
1698 fn check_assoc_item(
1701 assoc_item_kind: AssocItemKind,
1702 defaultness: hir::Defaultness,
1703 vis: ty::Visibility,
1705 let mut check = self.check(hir_id, vis);
1707 let (check_ty, is_assoc_ty) = match assoc_item_kind {
1708 AssocItemKind::Const | AssocItemKind::Method { .. } => (true, false),
1709 AssocItemKind::Type => (defaultness.has_value(), true),
1710 // `ty()` for existential types is the underlying type,
1711 // it's not a part of interface, so we skip it.
1712 AssocItemKind::Existential => (false, true),
1714 check.in_assoc_ty = is_assoc_ty;
1715 check.generics().predicates();
1722 impl<'a, 'tcx> Visitor<'tcx> for PrivateItemsInPublicInterfacesVisitor<'a, 'tcx> {
1723 fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> {
1724 NestedVisitorMap::OnlyBodies(&self.tcx.hir())
1727 fn visit_item(&mut self, item: &'tcx hir::Item) {
1729 let item_visibility = ty::Visibility::from_hir(&item.vis, item.hir_id, tcx);
1732 // Crates are always public.
1733 hir::ItemKind::ExternCrate(..) => {}
1734 // All nested items are checked by `visit_item`.
1735 hir::ItemKind::Mod(..) => {}
1736 // Checked in resolve.
1737 hir::ItemKind::Use(..) => {}
1739 hir::ItemKind::GlobalAsm(..) => {}
1740 // Subitems of these items have inherited publicity.
1741 hir::ItemKind::Const(..) | hir::ItemKind::Static(..) |
1742 hir::ItemKind::Fn(..) | hir::ItemKind::Ty(..) => {
1743 self.check(item.hir_id, item_visibility).generics().predicates().ty();
1745 hir::ItemKind::Existential(..) => {
1746 // `ty()` for existential types is the underlying type,
1747 // it's not a part of interface, so we skip it.
1748 self.check(item.hir_id, item_visibility).generics().predicates();
1750 hir::ItemKind::Trait(.., ref trait_item_refs) => {
1751 self.check(item.hir_id, item_visibility).generics().predicates();
1753 for trait_item_ref in trait_item_refs {
1754 self.check_assoc_item(
1755 trait_item_ref.id.hir_id,
1756 trait_item_ref.kind,
1757 trait_item_ref.defaultness,
1762 hir::ItemKind::TraitAlias(..) => {
1763 self.check(item.hir_id, item_visibility).generics().predicates();
1765 hir::ItemKind::Enum(ref def, _) => {
1766 self.check(item.hir_id, item_visibility).generics().predicates();
1768 for variant in &def.variants {
1769 for field in variant.node.data.fields() {
1770 self.check(field.hir_id, item_visibility).ty();
1774 // Subitems of foreign modules have their own publicity.
1775 hir::ItemKind::ForeignMod(ref foreign_mod) => {
1776 for foreign_item in &foreign_mod.items {
1777 let vis = ty::Visibility::from_hir(&foreign_item.vis, item.hir_id, tcx);
1778 self.check(foreign_item.hir_id, vis).generics().predicates().ty();
1781 // Subitems of structs and unions have their own publicity.
1782 hir::ItemKind::Struct(ref struct_def, _) |
1783 hir::ItemKind::Union(ref struct_def, _) => {
1784 self.check(item.hir_id, item_visibility).generics().predicates();
1786 for field in struct_def.fields() {
1787 let field_visibility = ty::Visibility::from_hir(&field.vis, item.hir_id, tcx);
1788 self.check(field.hir_id, min(item_visibility, field_visibility, tcx)).ty();
1791 // An inherent impl is public when its type is public
1792 // Subitems of inherent impls have their own publicity.
1793 // A trait impl is public when both its type and its trait are public
1794 // Subitems of trait impls have inherited publicity.
1795 hir::ItemKind::Impl(.., ref trait_ref, _, ref impl_item_refs) => {
1796 let impl_vis = ty::Visibility::of_impl(item.hir_id, tcx, &Default::default());
1797 self.check(item.hir_id, impl_vis).generics().predicates();
1798 for impl_item_ref in impl_item_refs {
1799 let impl_item = tcx.hir().impl_item(impl_item_ref.id);
1800 let impl_item_vis = if trait_ref.is_none() {
1801 min(ty::Visibility::from_hir(&impl_item.vis, item.hir_id, tcx),
1807 self.check_assoc_item(
1808 impl_item_ref.id.hir_id,
1810 impl_item_ref.defaultness,
1819 pub fn provide(providers: &mut Providers<'_>) {
1820 *providers = Providers {
1821 privacy_access_levels,
1822 check_private_in_public,
1828 fn check_mod_privacy(tcx: TyCtxt<'_>, module_def_id: DefId) {
1829 let empty_tables = ty::TypeckTables::empty(None);
1831 // Check privacy of names not checked in previous compilation stages.
1832 let mut visitor = NamePrivacyVisitor {
1834 tables: &empty_tables,
1835 current_item: hir::DUMMY_HIR_ID,
1836 empty_tables: &empty_tables,
1838 let (module, span, hir_id) = tcx.hir().get_module(module_def_id);
1840 intravisit::walk_mod(&mut visitor, module, hir_id);
1842 // Check privacy of explicitly written types and traits as well as
1843 // inferred types of expressions and patterns.
1844 let mut visitor = TypePrivacyVisitor {
1846 tables: &empty_tables,
1847 current_item: module_def_id,
1850 empty_tables: &empty_tables,
1852 intravisit::walk_mod(&mut visitor, module, hir_id);
1855 fn privacy_access_levels(tcx: TyCtxt<'_>, krate: CrateNum) -> &AccessLevels {
1856 assert_eq!(krate, LOCAL_CRATE);
1858 // Build up a set of all exported items in the AST. This is a set of all
1859 // items which are reachable from external crates based on visibility.
1860 let mut visitor = EmbargoVisitor {
1862 access_levels: Default::default(),
1863 prev_level: Some(AccessLevel::Public),
1867 intravisit::walk_crate(&mut visitor, tcx.hir().krate());
1868 if visitor.changed {
1869 visitor.changed = false;
1874 visitor.update(hir::CRATE_HIR_ID, Some(AccessLevel::Public));
1876 tcx.arena.alloc(visitor.access_levels)
1879 fn check_private_in_public(tcx: TyCtxt<'_>, krate: CrateNum) {
1880 assert_eq!(krate, LOCAL_CRATE);
1882 let access_levels = tcx.privacy_access_levels(LOCAL_CRATE);
1884 let krate = tcx.hir().krate();
1886 let mut visitor = ObsoleteVisiblePrivateTypesVisitor {
1888 access_levels: &access_levels,
1890 old_error_set: Default::default(),
1892 intravisit::walk_crate(&mut visitor, krate);
1894 let has_pub_restricted = {
1895 let mut pub_restricted_visitor = PubRestrictedVisitor {
1897 has_pub_restricted: false
1899 intravisit::walk_crate(&mut pub_restricted_visitor, krate);
1900 pub_restricted_visitor.has_pub_restricted
1903 // Check for private types and traits in public interfaces.
1904 let mut visitor = PrivateItemsInPublicInterfacesVisitor {
1907 old_error_set: &visitor.old_error_set,
1909 krate.visit_all_item_likes(&mut DeepVisitor::new(&mut visitor));
1912 __build_diagnostic_array! { librustc_privacy, DIAGNOSTICS }