1 #![doc(html_root_url = "https://doc.rust-lang.org/nightly/")]
3 #![deny(rust_2018_idioms)]
4 #![deny(unused_lifetimes)]
6 #![feature(in_band_lifetimes)]
8 #![feature(rustc_diagnostic_macros)]
10 #![recursion_limit="256"]
12 #[macro_use] extern crate syntax;
15 use rustc::hir::{self, Node, PatKind, AssocItemKind};
16 use rustc::hir::def::{Res, DefKind};
17 use rustc::hir::def_id::{CRATE_DEF_INDEX, LOCAL_CRATE, CrateNum, DefId};
18 use rustc::hir::intravisit::{self, Visitor, NestedVisitorMap};
19 use rustc::hir::itemlikevisit::DeepVisitor;
21 use rustc::middle::privacy::{AccessLevel, AccessLevels};
22 use rustc::ty::{self, TyCtxt, Ty, TraitRef, TypeFoldable, GenericParamDefKind};
23 use rustc::ty::fold::TypeVisitor;
24 use rustc::ty::query::Providers;
25 use rustc::ty::subst::InternalSubsts;
26 use rustc::util::nodemap::HirIdSet;
27 use rustc_data_structures::fx::FxHashSet;
28 use syntax::ast::Ident;
30 use syntax::symbol::{kw, sym};
33 use std::{cmp, fmt, mem};
34 use std::marker::PhantomData;
38 ////////////////////////////////////////////////////////////////////////////////
39 /// Generic infrastructure used to implement specific visitors below.
40 ////////////////////////////////////////////////////////////////////////////////
42 /// Implemented to visit all `DefId`s in a type.
43 /// Visiting `DefId`s is useful because visibilities and reachabilities are attached to them.
44 /// The idea is to visit "all components of a type", as documented in
45 /// https://github.com/rust-lang/rfcs/blob/master/text/2145-type-privacy.md#how-to-determine-visibility-of-a-type.
46 /// The default type visitor (`TypeVisitor`) does most of the job, but it has some shortcomings.
47 /// First, it doesn't have overridable `fn visit_trait_ref`, so we have to catch trait `DefId`s
48 /// manually. Second, it doesn't visit some type components like signatures of fn types, or traits
49 /// in `impl Trait`, see individual comments in `DefIdVisitorSkeleton::visit_ty`.
50 trait DefIdVisitor<'tcx> {
51 fn tcx(&self) -> TyCtxt<'tcx>;
52 fn shallow(&self) -> bool { false }
53 fn skip_assoc_tys(&self) -> bool { false }
54 fn visit_def_id(&mut self, def_id: DefId, kind: &str, descr: &dyn fmt::Display) -> bool;
56 /// Not overridden, but used to actually visit types and traits.
57 fn skeleton(&mut self) -> DefIdVisitorSkeleton<'_, 'tcx, Self> {
58 DefIdVisitorSkeleton {
60 visited_opaque_tys: Default::default(),
61 dummy: Default::default(),
64 fn visit(&mut self, ty_fragment: impl TypeFoldable<'tcx>) -> bool {
65 ty_fragment.visit_with(&mut self.skeleton())
67 fn visit_trait(&mut self, trait_ref: TraitRef<'tcx>) -> bool {
68 self.skeleton().visit_trait(trait_ref)
70 fn visit_predicates(&mut self, predicates: &ty::GenericPredicates<'tcx>) -> bool {
71 self.skeleton().visit_predicates(predicates)
75 struct DefIdVisitorSkeleton<'v, 'tcx, V>
77 V: DefIdVisitor<'tcx> + ?Sized,
79 def_id_visitor: &'v mut V,
80 visited_opaque_tys: FxHashSet<DefId>,
81 dummy: PhantomData<TyCtxt<'tcx>>,
84 impl<'tcx, V> DefIdVisitorSkeleton<'_, 'tcx, V>
86 V: DefIdVisitor<'tcx> + ?Sized,
88 fn visit_trait(&mut self, trait_ref: TraitRef<'tcx>) -> bool {
89 let TraitRef { def_id, substs } = trait_ref;
90 self.def_id_visitor.visit_def_id(def_id, "trait", &trait_ref) ||
91 (!self.def_id_visitor.shallow() && substs.visit_with(self))
94 fn visit_predicates(&mut self, predicates: &ty::GenericPredicates<'tcx>) -> bool {
95 let ty::GenericPredicates { parent: _, predicates } = predicates;
96 for (predicate, _span) in predicates {
98 ty::Predicate::Trait(poly_predicate) => {
99 let ty::TraitPredicate { trait_ref } = *poly_predicate.skip_binder();
100 if self.visit_trait(trait_ref) {
104 ty::Predicate::Projection(poly_predicate) => {
105 let ty::ProjectionPredicate { projection_ty, ty } =
106 *poly_predicate.skip_binder();
107 if ty.visit_with(self) {
110 if self.visit_trait(projection_ty.trait_ref(self.def_id_visitor.tcx())) {
114 ty::Predicate::TypeOutlives(poly_predicate) => {
115 let ty::OutlivesPredicate(ty, _region) = *poly_predicate.skip_binder();
116 if ty.visit_with(self) {
120 ty::Predicate::RegionOutlives(..) => {},
121 _ => bug!("unexpected predicate: {:?}", predicate),
128 impl<'tcx, V> TypeVisitor<'tcx> for DefIdVisitorSkeleton<'_, 'tcx, V>
130 V: DefIdVisitor<'tcx> + ?Sized,
132 fn visit_ty(&mut self, ty: Ty<'tcx>) -> bool {
133 let tcx = self.def_id_visitor.tcx();
134 // InternalSubsts are not visited here because they are visited below in `super_visit_with`.
136 ty::Adt(&ty::AdtDef { did: def_id, .. }, ..) |
137 ty::Foreign(def_id) |
138 ty::FnDef(def_id, ..) |
139 ty::Closure(def_id, ..) |
140 ty::Generator(def_id, ..) => {
141 if self.def_id_visitor.visit_def_id(def_id, "type", &ty) {
144 if self.def_id_visitor.shallow() {
147 // Default type visitor doesn't visit signatures of fn types.
148 // Something like `fn() -> Priv {my_func}` is considered a private type even if
149 // `my_func` is public, so we need to visit signatures.
150 if let ty::FnDef(..) = ty.sty {
151 if tcx.fn_sig(def_id).visit_with(self) {
155 // Inherent static methods don't have self type in substs.
156 // Something like `fn() {my_method}` type of the method
157 // `impl Pub<Priv> { pub fn my_method() {} }` is considered a private type,
158 // so we need to visit the self type additionally.
159 if let Some(assoc_item) = tcx.opt_associated_item(def_id) {
160 if let ty::ImplContainer(impl_def_id) = assoc_item.container {
161 if tcx.type_of(impl_def_id).visit_with(self) {
167 ty::Projection(proj) | ty::UnnormalizedProjection(proj) => {
168 if self.def_id_visitor.skip_assoc_tys() {
169 // Visitors searching for minimal visibility/reachability want to
170 // conservatively approximate associated types like `<Type as Trait>::Alias`
171 // as visible/reachable even if both `Type` and `Trait` are private.
172 // Ideally, associated types should be substituted in the same way as
173 // free type aliases, but this isn't done yet.
176 // This will also visit substs if necessary, so we don't need to recurse.
177 return self.visit_trait(proj.trait_ref(tcx));
179 ty::Dynamic(predicates, ..) => {
180 // All traits in the list are considered the "primary" part of the type
181 // and are visited by shallow visitors.
182 for predicate in *predicates.skip_binder() {
183 let trait_ref = match *predicate {
184 ty::ExistentialPredicate::Trait(trait_ref) => trait_ref,
185 ty::ExistentialPredicate::Projection(proj) => proj.trait_ref(tcx),
186 ty::ExistentialPredicate::AutoTrait(def_id) =>
187 ty::ExistentialTraitRef { def_id, substs: InternalSubsts::empty() },
189 let ty::ExistentialTraitRef { def_id, substs: _ } = trait_ref;
190 if self.def_id_visitor.visit_def_id(def_id, "trait", &trait_ref) {
195 ty::Opaque(def_id, ..) => {
196 // Skip repeated `Opaque`s to avoid infinite recursion.
197 if self.visited_opaque_tys.insert(def_id) {
198 // The intent is to treat `impl Trait1 + Trait2` identically to
199 // `dyn Trait1 + Trait2`. Therefore we ignore def-id of the opaque type itself
200 // (it either has no visibility, or its visibility is insignificant, like
201 // visibilities of type aliases) and recurse into predicates instead to go
202 // through the trait list (default type visitor doesn't visit those traits).
203 // All traits in the list are considered the "primary" part of the type
204 // and are visited by shallow visitors.
205 if self.visit_predicates(tcx.predicates_of(def_id)) {
210 // These types don't have their own def-ids (but may have subcomponents
211 // with def-ids that should be visited recursively).
212 ty::Bool | ty::Char | ty::Int(..) | ty::Uint(..) |
213 ty::Float(..) | ty::Str | ty::Never |
214 ty::Array(..) | ty::Slice(..) | ty::Tuple(..) |
215 ty::RawPtr(..) | ty::Ref(..) | ty::FnPtr(..) |
216 ty::Param(..) | ty::Error | ty::GeneratorWitness(..) => {}
217 ty::Bound(..) | ty::Placeholder(..) | ty::Infer(..) =>
218 bug!("unexpected type: {:?}", ty),
221 !self.def_id_visitor.shallow() && ty.super_visit_with(self)
225 fn def_id_visibility<'tcx>(
228 ) -> (ty::Visibility, Span, &'static str) {
229 match tcx.hir().as_local_hir_id(def_id) {
231 let vis = match tcx.hir().get(hir_id) {
232 Node::Item(item) => &item.vis,
233 Node::ForeignItem(foreign_item) => &foreign_item.vis,
234 Node::TraitItem(..) | Node::Variant(..) => {
235 return def_id_visibility(tcx, tcx.hir().get_parent_did(hir_id));
237 Node::ImplItem(impl_item) => {
238 match tcx.hir().get(tcx.hir().get_parent_item(hir_id)) {
239 Node::Item(item) => match &item.node {
240 hir::ItemKind::Impl(.., None, _, _) => &impl_item.vis,
241 hir::ItemKind::Impl(.., Some(trait_ref), _, _)
242 => return def_id_visibility(tcx, trait_ref.path.res.def_id()),
243 kind => bug!("unexpected item kind: {:?}", kind),
245 node => bug!("unexpected node kind: {:?}", node),
248 Node::Ctor(vdata) => {
249 let parent_hir_id = tcx.hir().get_parent_node(hir_id);
250 match tcx.hir().get(parent_hir_id) {
251 Node::Variant(..) => {
252 let parent_did = tcx.hir().local_def_id(parent_hir_id);
253 let (mut ctor_vis, mut span, mut descr) = def_id_visibility(
257 let adt_def = tcx.adt_def(tcx.hir().get_parent_did(hir_id));
258 let ctor_did = tcx.hir().local_def_id(
259 vdata.ctor_hir_id().unwrap());
260 let variant = adt_def.variant_with_ctor_id(ctor_did);
262 if variant.is_field_list_non_exhaustive() &&
263 ctor_vis == ty::Visibility::Public
265 ctor_vis = ty::Visibility::Restricted(
266 DefId::local(CRATE_DEF_INDEX));
267 let attrs = tcx.get_attrs(variant.def_id);
268 span = attr::find_by_name(&attrs, sym::non_exhaustive)
270 descr = "crate-visible";
273 return (ctor_vis, span, descr);
276 let item = match tcx.hir().get(parent_hir_id) {
277 Node::Item(item) => item,
278 node => bug!("unexpected node kind: {:?}", node),
280 let (mut ctor_vis, mut span, mut descr) =
281 (ty::Visibility::from_hir(&item.vis, parent_hir_id, tcx),
282 item.vis.span, item.vis.node.descr());
283 for field in vdata.fields() {
284 let field_vis = ty::Visibility::from_hir(&field.vis, hir_id, tcx);
285 if ctor_vis.is_at_least(field_vis, tcx) {
286 ctor_vis = field_vis;
287 span = field.vis.span;
288 descr = field.vis.node.descr();
292 // If the structure is marked as non_exhaustive then lower the
293 // visibility to within the crate.
294 if ctor_vis == ty::Visibility::Public {
296 tcx.adt_def(tcx.hir().get_parent_did(hir_id));
297 if adt_def.non_enum_variant().is_field_list_non_exhaustive() {
299 ty::Visibility::Restricted(DefId::local(CRATE_DEF_INDEX));
300 span = attr::find_by_name(&item.attrs, sym::non_exhaustive)
302 descr = "crate-visible";
306 return (ctor_vis, span, descr);
308 node => bug!("unexpected node kind: {:?}", node),
311 Node::Expr(expr) => {
312 return (ty::Visibility::Restricted(
313 tcx.hir().get_module_parent(expr.hir_id)),
314 expr.span, "private")
316 node => bug!("unexpected node kind: {:?}", node)
318 (ty::Visibility::from_hir(vis, hir_id, tcx), vis.span, vis.node.descr())
321 let vis = tcx.visibility(def_id);
322 let descr = if vis == ty::Visibility::Public { "public" } else { "private" };
323 (vis, tcx.def_span(def_id), descr)
328 // Set the correct `TypeckTables` for the given `item_id` (or an empty table if
329 // there is no `TypeckTables` for the item).
330 fn item_tables<'a, 'tcx>(
333 empty_tables: &'a ty::TypeckTables<'tcx>,
334 ) -> &'a ty::TypeckTables<'tcx> {
335 let def_id = tcx.hir().local_def_id(hir_id);
336 if tcx.has_typeck_tables(def_id) { tcx.typeck_tables_of(def_id) } else { empty_tables }
339 fn min(vis1: ty::Visibility, vis2: ty::Visibility, tcx: TyCtxt<'_>) -> ty::Visibility {
340 if vis1.is_at_least(vis2, tcx) { vis2 } else { vis1 }
343 ////////////////////////////////////////////////////////////////////////////////
344 /// Visitor used to determine if pub(restricted) is used anywhere in the crate.
346 /// This is done so that `private_in_public` warnings can be turned into hard errors
347 /// in crates that have been updated to use pub(restricted).
348 ////////////////////////////////////////////////////////////////////////////////
349 struct PubRestrictedVisitor<'tcx> {
351 has_pub_restricted: bool,
354 impl Visitor<'tcx> for PubRestrictedVisitor<'tcx> {
355 fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> {
356 NestedVisitorMap::All(&self.tcx.hir())
358 fn visit_vis(&mut self, vis: &'tcx hir::Visibility) {
359 self.has_pub_restricted = self.has_pub_restricted || vis.node.is_pub_restricted();
363 ////////////////////////////////////////////////////////////////////////////////
364 /// Visitor used to determine impl visibility and reachability.
365 ////////////////////////////////////////////////////////////////////////////////
367 struct FindMin<'a, 'tcx, VL: VisibilityLike> {
369 access_levels: &'a AccessLevels,
373 impl<'a, 'tcx, VL: VisibilityLike> DefIdVisitor<'tcx> for FindMin<'a, 'tcx, VL> {
374 fn tcx(&self) -> TyCtxt<'tcx> { self.tcx }
375 fn shallow(&self) -> bool { VL::SHALLOW }
376 fn skip_assoc_tys(&self) -> bool { true }
377 fn visit_def_id(&mut self, def_id: DefId, _kind: &str, _descr: &dyn fmt::Display) -> bool {
378 self.min = VL::new_min(self, def_id);
383 trait VisibilityLike: Sized {
385 const SHALLOW: bool = false;
386 fn new_min(find: &FindMin<'_, '_, Self>, def_id: DefId) -> Self;
388 // Returns an over-approximation (`skip_assoc_tys` = true) of visibility due to
389 // associated types for which we can't determine visibility precisely.
393 access_levels: &AccessLevels,
395 let mut find = FindMin { tcx, access_levels, min: Self::MAX };
396 let def_id = tcx.hir().local_def_id(hir_id);
397 find.visit(tcx.type_of(def_id));
398 if let Some(trait_ref) = tcx.impl_trait_ref(def_id) {
399 find.visit_trait(trait_ref);
404 impl VisibilityLike for ty::Visibility {
405 const MAX: Self = ty::Visibility::Public;
406 fn new_min(find: &FindMin<'_, '_, Self>, def_id: DefId) -> Self {
407 min(def_id_visibility(find.tcx, def_id).0, find.min, find.tcx)
410 impl VisibilityLike for Option<AccessLevel> {
411 const MAX: Self = Some(AccessLevel::Public);
412 // Type inference is very smart sometimes.
413 // It can make an impl reachable even some components of its type or trait are unreachable.
414 // E.g. methods of `impl ReachableTrait<UnreachableTy> for ReachableTy<UnreachableTy> { ... }`
415 // can be usable from other crates (#57264). So we skip substs when calculating reachability
416 // and consider an impl reachable if its "shallow" type and trait are reachable.
418 // The assumption we make here is that type-inference won't let you use an impl without knowing
419 // both "shallow" version of its self type and "shallow" version of its trait if it exists
420 // (which require reaching the `DefId`s in them).
421 const SHALLOW: bool = true;
422 fn new_min(find: &FindMin<'_, '_, Self>, def_id: DefId) -> Self {
423 cmp::min(if let Some(hir_id) = find.tcx.hir().as_local_hir_id(def_id) {
424 find.access_levels.map.get(&hir_id).cloned()
431 ////////////////////////////////////////////////////////////////////////////////
432 /// The embargo visitor, used to determine the exports of the AST.
433 ////////////////////////////////////////////////////////////////////////////////
435 struct EmbargoVisitor<'tcx> {
438 // Accessibility levels for reachable nodes.
439 access_levels: AccessLevels,
440 // Previous accessibility level; `None` means unreachable.
441 prev_level: Option<AccessLevel>,
442 // Has something changed in the level map?
446 struct ReachEverythingInTheInterfaceVisitor<'a, 'tcx> {
447 access_level: Option<AccessLevel>,
449 ev: &'a mut EmbargoVisitor<'tcx>,
452 impl EmbargoVisitor<'tcx> {
453 fn get(&self, id: hir::HirId) -> Option<AccessLevel> {
454 self.access_levels.map.get(&id).cloned()
457 // Updates node level and returns the updated level.
458 fn update(&mut self, id: hir::HirId, level: Option<AccessLevel>) -> Option<AccessLevel> {
459 let old_level = self.get(id);
460 // Accessibility levels can only grow.
461 if level > old_level {
462 self.access_levels.map.insert(id, level.unwrap());
473 access_level: Option<AccessLevel>,
474 ) -> ReachEverythingInTheInterfaceVisitor<'_, 'tcx> {
475 ReachEverythingInTheInterfaceVisitor {
476 access_level: cmp::min(access_level, Some(AccessLevel::Reachable)),
477 item_def_id: self.tcx.hir().local_def_id(item_id),
483 /// Given the path segments of a `ItemKind::Use`, then we need
484 /// to update the visibility of the intermediate use so that it isn't linted
485 /// by `unreachable_pub`.
487 /// This isn't trivial as `path.res` has the `DefId` of the eventual target
488 /// of the use statement not of the next intermediate use statement.
490 /// To do this, consider the last two segments of the path to our intermediate
491 /// use statement. We expect the penultimate segment to be a module and the
492 /// last segment to be the name of the item we are exporting. We can then
493 /// look at the items contained in the module for the use statement with that
494 /// name and update that item's visibility.
496 /// FIXME: This solution won't work with glob imports and doesn't respect
497 /// namespaces. See <https://github.com/rust-lang/rust/pull/57922#discussion_r251234202>.
498 fn update_visibility_of_intermediate_use_statements(&mut self, segments: &[hir::PathSegment]) {
499 if let Some([module, segment]) = segments.rchunks_exact(2).next() {
500 if let Some(item) = module.res
501 .and_then(|res| res.mod_def_id())
502 .and_then(|def_id| self.tcx.hir().as_local_hir_id(def_id))
503 .map(|module_hir_id| self.tcx.hir().expect_item(module_hir_id))
505 if let hir::ItemKind::Mod(m) = &item.node {
506 for item_id in m.item_ids.as_ref() {
507 let item = self.tcx.hir().expect_item(item_id.id);
508 let def_id = self.tcx.hir().local_def_id(item_id.id);
509 if !self.tcx.hygienic_eq(segment.ident, item.ident, def_id) { continue; }
510 if let hir::ItemKind::Use(..) = item.node {
511 self.update(item.hir_id, Some(AccessLevel::Exported));
520 impl Visitor<'tcx> for EmbargoVisitor<'tcx> {
521 /// We want to visit items in the context of their containing
522 /// module and so forth, so supply a crate for doing a deep walk.
523 fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> {
524 NestedVisitorMap::All(&self.tcx.hir())
527 fn visit_item(&mut self, item: &'tcx hir::Item) {
528 let inherited_item_level = match item.node {
529 hir::ItemKind::Impl(..) =>
530 Option::<AccessLevel>::of_impl(item.hir_id, self.tcx, &self.access_levels),
531 // Foreign modules inherit level from parents.
532 hir::ItemKind::ForeignMod(..) => self.prev_level,
533 // Other `pub` items inherit levels from parents.
534 hir::ItemKind::Const(..) | hir::ItemKind::Enum(..) | hir::ItemKind::ExternCrate(..) |
535 hir::ItemKind::GlobalAsm(..) | hir::ItemKind::Fn(..) | hir::ItemKind::Mod(..) |
536 hir::ItemKind::Static(..) | hir::ItemKind::Struct(..) |
537 hir::ItemKind::Trait(..) | hir::ItemKind::TraitAlias(..) |
538 hir::ItemKind::Existential(..) |
539 hir::ItemKind::Ty(..) | hir::ItemKind::Union(..) | hir::ItemKind::Use(..) => {
540 if item.vis.node.is_pub() { self.prev_level } else { None }
544 // Update level of the item itself.
545 let item_level = self.update(item.hir_id, inherited_item_level);
547 // Update levels of nested things.
549 hir::ItemKind::Enum(ref def, _) => {
550 for variant in &def.variants {
551 let variant_level = self.update(variant.node.id, item_level);
552 if let Some(ctor_hir_id) = variant.node.data.ctor_hir_id() {
553 self.update(ctor_hir_id, item_level);
555 for field in variant.node.data.fields() {
556 self.update(field.hir_id, variant_level);
560 hir::ItemKind::Impl(.., ref trait_ref, _, ref impl_item_refs) => {
561 for impl_item_ref in impl_item_refs {
562 if trait_ref.is_some() || impl_item_ref.vis.node.is_pub() {
563 self.update(impl_item_ref.id.hir_id, item_level);
567 hir::ItemKind::Trait(.., ref trait_item_refs) => {
568 for trait_item_ref in trait_item_refs {
569 self.update(trait_item_ref.id.hir_id, item_level);
572 hir::ItemKind::Struct(ref def, _) | hir::ItemKind::Union(ref def, _) => {
573 if let Some(ctor_hir_id) = def.ctor_hir_id() {
574 self.update(ctor_hir_id, item_level);
576 for field in def.fields() {
577 if field.vis.node.is_pub() {
578 self.update(field.hir_id, item_level);
582 hir::ItemKind::ForeignMod(ref foreign_mod) => {
583 for foreign_item in &foreign_mod.items {
584 if foreign_item.vis.node.is_pub() {
585 self.update(foreign_item.hir_id, item_level);
589 hir::ItemKind::Existential(..) |
590 hir::ItemKind::Use(..) |
591 hir::ItemKind::Static(..) |
592 hir::ItemKind::Const(..) |
593 hir::ItemKind::GlobalAsm(..) |
594 hir::ItemKind::Ty(..) |
595 hir::ItemKind::Mod(..) |
596 hir::ItemKind::TraitAlias(..) |
597 hir::ItemKind::Fn(..) |
598 hir::ItemKind::ExternCrate(..) => {}
601 // Mark all items in interfaces of reachable items as reachable.
603 // The interface is empty.
604 hir::ItemKind::ExternCrate(..) => {}
605 // All nested items are checked by `visit_item`.
606 hir::ItemKind::Mod(..) => {}
607 // Re-exports are handled in `visit_mod`. However, in order to avoid looping over
608 // all of the items of a mod in `visit_mod` looking for use statements, we handle
609 // making sure that intermediate use statements have their visibilities updated here.
610 hir::ItemKind::Use(ref path, _) => {
611 if item_level.is_some() {
612 self.update_visibility_of_intermediate_use_statements(path.segments.as_ref());
615 // The interface is empty.
616 hir::ItemKind::GlobalAsm(..) => {}
617 hir::ItemKind::Existential(..) => {
618 // FIXME: This is some serious pessimization intended to workaround deficiencies
619 // in the reachability pass (`middle/reachable.rs`). Types are marked as link-time
620 // reachable if they are returned via `impl Trait`, even from private functions.
621 let exist_level = cmp::max(item_level, Some(AccessLevel::ReachableFromImplTrait));
622 self.reach(item.hir_id, exist_level).generics().predicates().ty();
625 hir::ItemKind::Const(..) | hir::ItemKind::Static(..) |
626 hir::ItemKind::Fn(..) | hir::ItemKind::Ty(..) => {
627 if item_level.is_some() {
628 self.reach(item.hir_id, item_level).generics().predicates().ty();
631 hir::ItemKind::Trait(.., ref trait_item_refs) => {
632 if item_level.is_some() {
633 self.reach(item.hir_id, item_level).generics().predicates();
635 for trait_item_ref in trait_item_refs {
636 let mut reach = self.reach(trait_item_ref.id.hir_id, item_level);
637 reach.generics().predicates();
639 if trait_item_ref.kind == AssocItemKind::Type &&
640 !trait_item_ref.defaultness.has_value() {
648 hir::ItemKind::TraitAlias(..) => {
649 if item_level.is_some() {
650 self.reach(item.hir_id, item_level).generics().predicates();
653 // Visit everything except for private impl items.
654 hir::ItemKind::Impl(.., ref impl_item_refs) => {
655 if item_level.is_some() {
656 self.reach(item.hir_id, item_level).generics().predicates().ty().trait_ref();
658 for impl_item_ref in impl_item_refs {
659 let impl_item_level = self.get(impl_item_ref.id.hir_id);
660 if impl_item_level.is_some() {
661 self.reach(impl_item_ref.id.hir_id, impl_item_level)
662 .generics().predicates().ty();
668 // Visit everything, but enum variants have their own levels.
669 hir::ItemKind::Enum(ref def, _) => {
670 if item_level.is_some() {
671 self.reach(item.hir_id, item_level).generics().predicates();
673 for variant in &def.variants {
674 let variant_level = self.get(variant.node.id);
675 if variant_level.is_some() {
676 for field in variant.node.data.fields() {
677 self.reach(field.hir_id, variant_level).ty();
679 // Corner case: if the variant is reachable, but its
680 // enum is not, make the enum reachable as well.
681 self.update(item.hir_id, variant_level);
685 // Visit everything, but foreign items have their own levels.
686 hir::ItemKind::ForeignMod(ref foreign_mod) => {
687 for foreign_item in &foreign_mod.items {
688 let foreign_item_level = self.get(foreign_item.hir_id);
689 if foreign_item_level.is_some() {
690 self.reach(foreign_item.hir_id, foreign_item_level)
691 .generics().predicates().ty();
695 // Visit everything except for private fields.
696 hir::ItemKind::Struct(ref struct_def, _) |
697 hir::ItemKind::Union(ref struct_def, _) => {
698 if item_level.is_some() {
699 self.reach(item.hir_id, item_level).generics().predicates();
700 for field in struct_def.fields() {
701 let field_level = self.get(field.hir_id);
702 if field_level.is_some() {
703 self.reach(field.hir_id, field_level).ty();
710 let orig_level = mem::replace(&mut self.prev_level, item_level);
711 intravisit::walk_item(self, item);
712 self.prev_level = orig_level;
715 fn visit_block(&mut self, b: &'tcx hir::Block) {
716 // Blocks can have public items, for example impls, but they always
717 // start as completely private regardless of publicity of a function,
718 // constant, type, field, etc., in which this block resides.
719 let orig_level = mem::replace(&mut self.prev_level, None);
720 intravisit::walk_block(self, b);
721 self.prev_level = orig_level;
724 fn visit_mod(&mut self, m: &'tcx hir::Mod, _sp: Span, id: hir::HirId) {
725 // This code is here instead of in visit_item so that the
726 // crate module gets processed as well.
727 if self.prev_level.is_some() {
728 let def_id = self.tcx.hir().local_def_id(id);
729 if let Some(exports) = self.tcx.module_exports(def_id) {
730 for export in exports.iter() {
731 if export.vis == ty::Visibility::Public {
732 if let Some(def_id) = export.res.opt_def_id() {
733 if let Some(hir_id) = self.tcx.hir().as_local_hir_id(def_id) {
734 self.update(hir_id, Some(AccessLevel::Exported));
742 intravisit::walk_mod(self, m, id);
745 fn visit_macro_def(&mut self, md: &'tcx hir::MacroDef) {
747 self.update(md.hir_id, Some(AccessLevel::Public));
751 let module_did = ty::DefIdTree::parent(
753 self.tcx.hir().local_def_id(md.hir_id)
755 let mut module_id = self.tcx.hir().as_local_hir_id(module_did).unwrap();
756 let level = if md.vis.node.is_pub() { self.get(module_id) } else { None };
757 let level = self.update(md.hir_id, level);
763 let module = if module_id == hir::CRATE_HIR_ID {
764 &self.tcx.hir().krate().module
765 } else if let hir::ItemKind::Mod(ref module) =
766 self.tcx.hir().expect_item(module_id).node {
771 for id in &module.item_ids {
772 self.update(id.id, level);
774 let def_id = self.tcx.hir().local_def_id(module_id);
775 if let Some(exports) = self.tcx.module_exports(def_id) {
776 for export in exports.iter() {
777 if let Some(hir_id) = self.tcx.hir().as_local_hir_id(export.res.def_id()) {
778 self.update(hir_id, level);
783 if module_id == hir::CRATE_HIR_ID {
786 module_id = self.tcx.hir().get_parent_node(module_id);
791 impl ReachEverythingInTheInterfaceVisitor<'_, 'tcx> {
792 fn generics(&mut self) -> &mut Self {
793 for param in &self.ev.tcx.generics_of(self.item_def_id).params {
795 GenericParamDefKind::Lifetime => {}
796 GenericParamDefKind::Type { has_default, .. } => {
798 self.visit(self.ev.tcx.type_of(param.def_id));
801 GenericParamDefKind::Const => {
802 self.visit(self.ev.tcx.type_of(param.def_id));
809 fn predicates(&mut self) -> &mut Self {
810 self.visit_predicates(self.ev.tcx.predicates_of(self.item_def_id));
814 fn ty(&mut self) -> &mut Self {
815 self.visit(self.ev.tcx.type_of(self.item_def_id));
819 fn trait_ref(&mut self) -> &mut Self {
820 if let Some(trait_ref) = self.ev.tcx.impl_trait_ref(self.item_def_id) {
821 self.visit_trait(trait_ref);
827 impl DefIdVisitor<'tcx> for ReachEverythingInTheInterfaceVisitor<'_, 'tcx> {
828 fn tcx(&self) -> TyCtxt<'tcx> { self.ev.tcx }
829 fn visit_def_id(&mut self, def_id: DefId, _kind: &str, _descr: &dyn fmt::Display) -> bool {
830 if let Some(hir_id) = self.ev.tcx.hir().as_local_hir_id(def_id) {
831 self.ev.update(hir_id, self.access_level);
837 //////////////////////////////////////////////////////////////////////////////////////
838 /// Name privacy visitor, checks privacy and reports violations.
839 /// Most of name privacy checks are performed during the main resolution phase,
840 /// or later in type checking when field accesses and associated items are resolved.
841 /// This pass performs remaining checks for fields in struct expressions and patterns.
842 //////////////////////////////////////////////////////////////////////////////////////
844 struct NamePrivacyVisitor<'a, 'tcx> {
846 tables: &'a ty::TypeckTables<'tcx>,
847 current_item: hir::HirId,
848 empty_tables: &'a ty::TypeckTables<'tcx>,
851 impl<'a, 'tcx> NamePrivacyVisitor<'a, 'tcx> {
852 // Checks that a field in a struct constructor (expression or pattern) is accessible.
853 fn check_field(&mut self,
854 use_ctxt: Span, // syntax context of the field name at the use site
855 span: Span, // span of the field pattern, e.g., `x: 0`
856 def: &'tcx ty::AdtDef, // definition of the struct or enum
857 field: &'tcx ty::FieldDef) { // definition of the field
858 let ident = Ident::new(kw::Invalid, use_ctxt);
859 let current_hir = self.current_item;
860 let def_id = self.tcx.adjust_ident_and_get_scope(ident, def.did, current_hir).1;
861 if !def.is_enum() && !field.vis.is_accessible_from(def_id, self.tcx) {
862 struct_span_err!(self.tcx.sess, span, E0451, "field `{}` of {} `{}` is private",
863 field.ident, def.variant_descr(), self.tcx.def_path_str(def.did))
864 .span_label(span, format!("field `{}` is private", field.ident))
870 impl<'a, 'tcx> Visitor<'tcx> for NamePrivacyVisitor<'a, 'tcx> {
871 /// We want to visit items in the context of their containing
872 /// module and so forth, so supply a crate for doing a deep walk.
873 fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> {
874 NestedVisitorMap::All(&self.tcx.hir())
877 fn visit_mod(&mut self, _m: &'tcx hir::Mod, _s: Span, _n: hir::HirId) {
878 // Don't visit nested modules, since we run a separate visitor walk
879 // for each module in `privacy_access_levels`
882 fn visit_nested_body(&mut self, body: hir::BodyId) {
883 let orig_tables = mem::replace(&mut self.tables, self.tcx.body_tables(body));
884 let body = self.tcx.hir().body(body);
885 self.visit_body(body);
886 self.tables = orig_tables;
889 fn visit_item(&mut self, item: &'tcx hir::Item) {
890 let orig_current_item = mem::replace(&mut self.current_item, item.hir_id);
892 mem::replace(&mut self.tables, item_tables(self.tcx, item.hir_id, self.empty_tables));
893 intravisit::walk_item(self, item);
894 self.current_item = orig_current_item;
895 self.tables = orig_tables;
898 fn visit_trait_item(&mut self, ti: &'tcx hir::TraitItem) {
900 mem::replace(&mut self.tables, item_tables(self.tcx, ti.hir_id, self.empty_tables));
901 intravisit::walk_trait_item(self, ti);
902 self.tables = orig_tables;
905 fn visit_impl_item(&mut self, ii: &'tcx hir::ImplItem) {
907 mem::replace(&mut self.tables, item_tables(self.tcx, ii.hir_id, self.empty_tables));
908 intravisit::walk_impl_item(self, ii);
909 self.tables = orig_tables;
912 fn visit_expr(&mut self, expr: &'tcx hir::Expr) {
914 hir::ExprKind::Struct(ref qpath, ref fields, ref base) => {
915 let res = self.tables.qpath_res(qpath, expr.hir_id);
916 let adt = self.tables.expr_ty(expr).ty_adt_def().unwrap();
917 let variant = adt.variant_of_res(res);
918 if let Some(ref base) = *base {
919 // If the expression uses FRU we need to make sure all the unmentioned fields
920 // are checked for privacy (RFC 736). Rather than computing the set of
921 // unmentioned fields, just check them all.
922 for (vf_index, variant_field) in variant.fields.iter().enumerate() {
923 let field = fields.iter().find(|f| {
924 self.tcx.field_index(f.hir_id, self.tables) == vf_index
926 let (use_ctxt, span) = match field {
927 Some(field) => (field.ident.span, field.span),
928 None => (base.span, base.span),
930 self.check_field(use_ctxt, span, adt, variant_field);
933 for field in fields {
934 let use_ctxt = field.ident.span;
935 let index = self.tcx.field_index(field.hir_id, self.tables);
936 self.check_field(use_ctxt, field.span, adt, &variant.fields[index]);
943 intravisit::walk_expr(self, expr);
946 fn visit_pat(&mut self, pat: &'tcx hir::Pat) {
948 PatKind::Struct(ref qpath, ref fields, _) => {
949 let res = self.tables.qpath_res(qpath, pat.hir_id);
950 let adt = self.tables.pat_ty(pat).ty_adt_def().unwrap();
951 let variant = adt.variant_of_res(res);
952 for field in fields {
953 let use_ctxt = field.node.ident.span;
954 let index = self.tcx.field_index(field.node.hir_id, self.tables);
955 self.check_field(use_ctxt, field.span, adt, &variant.fields[index]);
961 intravisit::walk_pat(self, pat);
965 ////////////////////////////////////////////////////////////////////////////////////////////
966 /// Type privacy visitor, checks types for privacy and reports violations.
967 /// Both explicitly written types and inferred types of expressions and patters are checked.
968 /// Checks are performed on "semantic" types regardless of names and their hygiene.
969 ////////////////////////////////////////////////////////////////////////////////////////////
971 struct TypePrivacyVisitor<'a, 'tcx> {
973 tables: &'a ty::TypeckTables<'tcx>,
977 empty_tables: &'a ty::TypeckTables<'tcx>,
980 impl<'a, 'tcx> TypePrivacyVisitor<'a, 'tcx> {
981 fn item_is_accessible(&self, did: DefId) -> bool {
982 def_id_visibility(self.tcx, did).0.is_accessible_from(self.current_item, self.tcx)
985 // Take node-id of an expression or pattern and check its type for privacy.
986 fn check_expr_pat_type(&mut self, id: hir::HirId, span: Span) -> bool {
988 if self.visit(self.tables.node_type(id)) || self.visit(self.tables.node_substs(id)) {
991 if let Some(adjustments) = self.tables.adjustments().get(id) {
992 for adjustment in adjustments {
993 if self.visit(adjustment.target) {
1001 fn check_def_id(&mut self, def_id: DefId, kind: &str, descr: &dyn fmt::Display) -> bool {
1002 let is_error = !self.item_is_accessible(def_id);
1004 self.tcx.sess.span_err(self.span, &format!("{} `{}` is private", kind, descr));
1010 impl<'a, 'tcx> Visitor<'tcx> for TypePrivacyVisitor<'a, 'tcx> {
1011 /// We want to visit items in the context of their containing
1012 /// module and so forth, so supply a crate for doing a deep walk.
1013 fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> {
1014 NestedVisitorMap::All(&self.tcx.hir())
1017 fn visit_mod(&mut self, _m: &'tcx hir::Mod, _s: Span, _n: hir::HirId) {
1018 // Don't visit nested modules, since we run a separate visitor walk
1019 // for each module in `privacy_access_levels`
1022 fn visit_nested_body(&mut self, body: hir::BodyId) {
1023 let orig_tables = mem::replace(&mut self.tables, self.tcx.body_tables(body));
1024 let orig_in_body = mem::replace(&mut self.in_body, true);
1025 let body = self.tcx.hir().body(body);
1026 self.visit_body(body);
1027 self.tables = orig_tables;
1028 self.in_body = orig_in_body;
1031 fn visit_ty(&mut self, hir_ty: &'tcx hir::Ty) {
1032 self.span = hir_ty.span;
1035 if self.visit(self.tables.node_type(hir_ty.hir_id)) {
1039 // Types in signatures.
1040 // FIXME: This is very ineffective. Ideally each HIR type should be converted
1041 // into a semantic type only once and the result should be cached somehow.
1042 if self.visit(rustc_typeck::hir_ty_to_ty(self.tcx, hir_ty)) {
1047 intravisit::walk_ty(self, hir_ty);
1050 fn visit_trait_ref(&mut self, trait_ref: &'tcx hir::TraitRef) {
1051 self.span = trait_ref.path.span;
1053 // Avoid calling `hir_trait_to_predicates` in bodies, it will ICE.
1054 // The traits' privacy in bodies is already checked as a part of trait object types.
1055 let (principal, bounds) = rustc_typeck::hir_trait_to_predicates(self.tcx, trait_ref);
1056 if self.visit_trait(*principal.skip_binder()) {
1059 for (poly_predicate, _) in bounds.projection_bounds {
1061 if self.visit(poly_predicate.skip_binder().ty) ||
1062 self.visit_trait(poly_predicate.skip_binder().projection_ty.trait_ref(tcx)) {
1068 intravisit::walk_trait_ref(self, trait_ref);
1071 // Check types of expressions
1072 fn visit_expr(&mut self, expr: &'tcx hir::Expr) {
1073 if self.check_expr_pat_type(expr.hir_id, expr.span) {
1074 // Do not check nested expressions if the error already happened.
1078 hir::ExprKind::Assign(.., ref rhs) | hir::ExprKind::Match(ref rhs, ..) => {
1079 // Do not report duplicate errors for `x = y` and `match x { ... }`.
1080 if self.check_expr_pat_type(rhs.hir_id, rhs.span) {
1084 hir::ExprKind::MethodCall(_, span, _) => {
1085 // Method calls have to be checked specially.
1087 if let Some(def_id) = self.tables.type_dependent_def_id(expr.hir_id) {
1088 if self.visit(self.tcx.type_of(def_id)) {
1092 self.tcx.sess.delay_span_bug(expr.span,
1093 "no type-dependent def for method call");
1099 intravisit::walk_expr(self, expr);
1102 // Prohibit access to associated items with insufficient nominal visibility.
1104 // Additionally, until better reachability analysis for macros 2.0 is available,
1105 // we prohibit access to private statics from other crates, this allows to give
1106 // more code internal visibility at link time. (Access to private functions
1107 // is already prohibited by type privacy for function types.)
1108 fn visit_qpath(&mut self, qpath: &'tcx hir::QPath, id: hir::HirId, span: Span) {
1109 let def = match self.tables.qpath_res(qpath, id) {
1110 Res::Def(kind, def_id) => Some((kind, def_id)),
1113 let def = def.filter(|(kind, _)| {
1116 | DefKind::AssocConst
1118 | DefKind::AssocExistential
1119 | DefKind::Static => true,
1123 if let Some((kind, def_id)) = def {
1124 let is_local_static = if let DefKind::Static = kind {
1127 if !self.item_is_accessible(def_id) && !is_local_static {
1128 let name = match *qpath {
1129 hir::QPath::Resolved(_, ref path) => path.to_string(),
1130 hir::QPath::TypeRelative(_, ref segment) => segment.ident.to_string(),
1132 let msg = format!("{} `{}` is private", kind.descr(), name);
1133 self.tcx.sess.span_err(span, &msg);
1138 intravisit::walk_qpath(self, qpath, id, span);
1141 // Check types of patterns.
1142 fn visit_pat(&mut self, pattern: &'tcx hir::Pat) {
1143 if self.check_expr_pat_type(pattern.hir_id, pattern.span) {
1144 // Do not check nested patterns if the error already happened.
1148 intravisit::walk_pat(self, pattern);
1151 fn visit_local(&mut self, local: &'tcx hir::Local) {
1152 if let Some(ref init) = local.init {
1153 if self.check_expr_pat_type(init.hir_id, init.span) {
1154 // Do not report duplicate errors for `let x = y`.
1159 intravisit::walk_local(self, local);
1162 // Check types in item interfaces.
1163 fn visit_item(&mut self, item: &'tcx hir::Item) {
1164 let orig_current_item = mem::replace(&mut self.current_item,
1165 self.tcx.hir().local_def_id(item.hir_id));
1166 let orig_in_body = mem::replace(&mut self.in_body, false);
1168 mem::replace(&mut self.tables, item_tables(self.tcx, item.hir_id, self.empty_tables));
1169 intravisit::walk_item(self, item);
1170 self.tables = orig_tables;
1171 self.in_body = orig_in_body;
1172 self.current_item = orig_current_item;
1175 fn visit_trait_item(&mut self, ti: &'tcx hir::TraitItem) {
1177 mem::replace(&mut self.tables, item_tables(self.tcx, ti.hir_id, self.empty_tables));
1178 intravisit::walk_trait_item(self, ti);
1179 self.tables = orig_tables;
1182 fn visit_impl_item(&mut self, ii: &'tcx hir::ImplItem) {
1184 mem::replace(&mut self.tables, item_tables(self.tcx, ii.hir_id, self.empty_tables));
1185 intravisit::walk_impl_item(self, ii);
1186 self.tables = orig_tables;
1190 impl DefIdVisitor<'tcx> for TypePrivacyVisitor<'a, 'tcx> {
1191 fn tcx(&self) -> TyCtxt<'tcx> { self.tcx }
1192 fn visit_def_id(&mut self, def_id: DefId, kind: &str, descr: &dyn fmt::Display) -> bool {
1193 self.check_def_id(def_id, kind, descr)
1197 ///////////////////////////////////////////////////////////////////////////////
1198 /// Obsolete visitors for checking for private items in public interfaces.
1199 /// These visitors are supposed to be kept in frozen state and produce an
1200 /// "old error node set". For backward compatibility the new visitor reports
1201 /// warnings instead of hard errors when the erroneous node is not in this old set.
1202 ///////////////////////////////////////////////////////////////////////////////
1204 struct ObsoleteVisiblePrivateTypesVisitor<'a, 'tcx> {
1206 access_levels: &'a AccessLevels,
1208 // Set of errors produced by this obsolete visitor.
1209 old_error_set: HirIdSet,
1212 struct ObsoleteCheckTypeForPrivatenessVisitor<'a, 'b, 'tcx> {
1213 inner: &'a ObsoleteVisiblePrivateTypesVisitor<'b, 'tcx>,
1214 /// Whether the type refers to private types.
1215 contains_private: bool,
1216 /// Whether we've recurred at all (i.e., if we're pointing at the
1217 /// first type on which `visit_ty` was called).
1218 at_outer_type: bool,
1219 /// Whether that first type is a public path.
1220 outer_type_is_public_path: bool,
1223 impl<'a, 'tcx> ObsoleteVisiblePrivateTypesVisitor<'a, 'tcx> {
1224 fn path_is_private_type(&self, path: &hir::Path) -> bool {
1225 let did = match path.res {
1226 Res::PrimTy(..) | Res::SelfTy(..) | Res::Err => return false,
1227 res => res.def_id(),
1230 // A path can only be private if:
1231 // it's in this crate...
1232 if let Some(hir_id) = self.tcx.hir().as_local_hir_id(did) {
1233 // .. and it corresponds to a private type in the AST (this returns
1234 // `None` for type parameters).
1235 match self.tcx.hir().find(hir_id) {
1236 Some(Node::Item(ref item)) => !item.vis.node.is_pub(),
1237 Some(_) | None => false,
1244 fn trait_is_public(&self, trait_id: hir::HirId) -> bool {
1245 // FIXME: this would preferably be using `exported_items`, but all
1246 // traits are exported currently (see `EmbargoVisitor.exported_trait`).
1247 self.access_levels.is_public(trait_id)
1250 fn check_generic_bound(&mut self, bound: &hir::GenericBound) {
1251 if let hir::GenericBound::Trait(ref trait_ref, _) = *bound {
1252 if self.path_is_private_type(&trait_ref.trait_ref.path) {
1253 self.old_error_set.insert(trait_ref.trait_ref.hir_ref_id);
1258 fn item_is_public(&self, id: &hir::HirId, vis: &hir::Visibility) -> bool {
1259 self.access_levels.is_reachable(*id) || vis.node.is_pub()
1263 impl<'a, 'b, 'tcx, 'v> Visitor<'v> for ObsoleteCheckTypeForPrivatenessVisitor<'a, 'b, 'tcx> {
1264 fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'v> {
1265 NestedVisitorMap::None
1268 fn visit_ty(&mut self, ty: &hir::Ty) {
1269 if let hir::TyKind::Path(hir::QPath::Resolved(_, ref path)) = ty.node {
1270 if self.inner.path_is_private_type(path) {
1271 self.contains_private = true;
1272 // Found what we're looking for, so let's stop working.
1276 if let hir::TyKind::Path(_) = ty.node {
1277 if self.at_outer_type {
1278 self.outer_type_is_public_path = true;
1281 self.at_outer_type = false;
1282 intravisit::walk_ty(self, ty)
1285 // Don't want to recurse into `[, .. expr]`.
1286 fn visit_expr(&mut self, _: &hir::Expr) {}
1289 impl<'a, 'tcx> Visitor<'tcx> for ObsoleteVisiblePrivateTypesVisitor<'a, 'tcx> {
1290 /// We want to visit items in the context of their containing
1291 /// module and so forth, so supply a crate for doing a deep walk.
1292 fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> {
1293 NestedVisitorMap::All(&self.tcx.hir())
1296 fn visit_item(&mut self, item: &'tcx hir::Item) {
1298 // Contents of a private mod can be re-exported, so we need
1299 // to check internals.
1300 hir::ItemKind::Mod(_) => {}
1302 // An `extern {}` doesn't introduce a new privacy
1303 // namespace (the contents have their own privacies).
1304 hir::ItemKind::ForeignMod(_) => {}
1306 hir::ItemKind::Trait(.., ref bounds, _) => {
1307 if !self.trait_is_public(item.hir_id) {
1311 for bound in bounds.iter() {
1312 self.check_generic_bound(bound)
1316 // Impls need some special handling to try to offer useful
1317 // error messages without (too many) false positives
1318 // (i.e., we could just return here to not check them at
1319 // all, or some worse estimation of whether an impl is
1320 // publicly visible).
1321 hir::ItemKind::Impl(.., ref g, ref trait_ref, ref self_, ref impl_item_refs) => {
1322 // `impl [... for] Private` is never visible.
1323 let self_contains_private;
1324 // `impl [... for] Public<...>`, but not `impl [... for]
1325 // Vec<Public>` or `(Public,)`, etc.
1326 let self_is_public_path;
1328 // Check the properties of the `Self` type:
1330 let mut visitor = ObsoleteCheckTypeForPrivatenessVisitor {
1332 contains_private: false,
1333 at_outer_type: true,
1334 outer_type_is_public_path: false,
1336 visitor.visit_ty(&self_);
1337 self_contains_private = visitor.contains_private;
1338 self_is_public_path = visitor.outer_type_is_public_path;
1341 // Miscellaneous info about the impl:
1343 // `true` iff this is `impl Private for ...`.
1344 let not_private_trait =
1345 trait_ref.as_ref().map_or(true, // no trait counts as public trait
1347 let did = tr.path.res.def_id();
1349 if let Some(hir_id) = self.tcx.hir().as_local_hir_id(did) {
1350 self.trait_is_public(hir_id)
1352 true // external traits must be public
1356 // `true` iff this is a trait impl or at least one method is public.
1358 // `impl Public { $( fn ...() {} )* }` is not visible.
1360 // This is required over just using the methods' privacy
1361 // directly because we might have `impl<T: Foo<Private>> ...`,
1362 // and we shouldn't warn about the generics if all the methods
1363 // are private (because `T` won't be visible externally).
1364 let trait_or_some_public_method =
1365 trait_ref.is_some() ||
1366 impl_item_refs.iter()
1367 .any(|impl_item_ref| {
1368 let impl_item = self.tcx.hir().impl_item(impl_item_ref.id);
1369 match impl_item.node {
1370 hir::ImplItemKind::Const(..) |
1371 hir::ImplItemKind::Method(..) => {
1372 self.access_levels.is_reachable(
1373 impl_item_ref.id.hir_id)
1375 hir::ImplItemKind::Existential(..) |
1376 hir::ImplItemKind::Type(_) => false,
1380 if !self_contains_private &&
1381 not_private_trait &&
1382 trait_or_some_public_method {
1384 intravisit::walk_generics(self, g);
1388 for impl_item_ref in impl_item_refs {
1389 // This is where we choose whether to walk down
1390 // further into the impl to check its items. We
1391 // should only walk into public items so that we
1392 // don't erroneously report errors for private
1393 // types in private items.
1394 let impl_item = self.tcx.hir().impl_item(impl_item_ref.id);
1395 match impl_item.node {
1396 hir::ImplItemKind::Const(..) |
1397 hir::ImplItemKind::Method(..)
1398 if self.item_is_public(&impl_item.hir_id, &impl_item.vis) =>
1400 intravisit::walk_impl_item(self, impl_item)
1402 hir::ImplItemKind::Type(..) => {
1403 intravisit::walk_impl_item(self, impl_item)
1410 // Any private types in a trait impl fall into three
1412 // 1. mentioned in the trait definition
1413 // 2. mentioned in the type params/generics
1414 // 3. mentioned in the associated types of the impl
1416 // Those in 1. can only occur if the trait is in
1417 // this crate and will've been warned about on the
1418 // trait definition (there's no need to warn twice
1419 // so we don't check the methods).
1421 // Those in 2. are warned via walk_generics and this
1423 intravisit::walk_path(self, &tr.path);
1425 // Those in 3. are warned with this call.
1426 for impl_item_ref in impl_item_refs {
1427 let impl_item = self.tcx.hir().impl_item(impl_item_ref.id);
1428 if let hir::ImplItemKind::Type(ref ty) = impl_item.node {
1434 } else if trait_ref.is_none() && self_is_public_path {
1435 // `impl Public<Private> { ... }`. Any public static
1436 // methods will be visible as `Public::foo`.
1437 let mut found_pub_static = false;
1438 for impl_item_ref in impl_item_refs {
1439 if self.item_is_public(&impl_item_ref.id.hir_id, &impl_item_ref.vis) {
1440 let impl_item = self.tcx.hir().impl_item(impl_item_ref.id);
1441 match impl_item_ref.kind {
1442 AssocItemKind::Const => {
1443 found_pub_static = true;
1444 intravisit::walk_impl_item(self, impl_item);
1446 AssocItemKind::Method { has_self: false } => {
1447 found_pub_static = true;
1448 intravisit::walk_impl_item(self, impl_item);
1454 if found_pub_static {
1455 intravisit::walk_generics(self, g)
1461 // `type ... = ...;` can contain private types, because
1462 // we're introducing a new name.
1463 hir::ItemKind::Ty(..) => return,
1465 // Not at all public, so we don't care.
1466 _ if !self.item_is_public(&item.hir_id, &item.vis) => {
1473 // We've carefully constructed it so that if we're here, then
1474 // any `visit_ty`'s will be called on things that are in
1475 // public signatures, i.e., things that we're interested in for
1477 intravisit::walk_item(self, item);
1480 fn visit_generics(&mut self, generics: &'tcx hir::Generics) {
1481 for param in &generics.params {
1482 for bound in ¶m.bounds {
1483 self.check_generic_bound(bound);
1486 for predicate in &generics.where_clause.predicates {
1488 hir::WherePredicate::BoundPredicate(bound_pred) => {
1489 for bound in bound_pred.bounds.iter() {
1490 self.check_generic_bound(bound)
1493 hir::WherePredicate::RegionPredicate(_) => {}
1494 hir::WherePredicate::EqPredicate(eq_pred) => {
1495 self.visit_ty(&eq_pred.rhs_ty);
1501 fn visit_foreign_item(&mut self, item: &'tcx hir::ForeignItem) {
1502 if self.access_levels.is_reachable(item.hir_id) {
1503 intravisit::walk_foreign_item(self, item)
1507 fn visit_ty(&mut self, t: &'tcx hir::Ty) {
1508 if let hir::TyKind::Path(hir::QPath::Resolved(_, ref path)) = t.node {
1509 if self.path_is_private_type(path) {
1510 self.old_error_set.insert(t.hir_id);
1513 intravisit::walk_ty(self, t)
1516 fn visit_variant(&mut self,
1517 v: &'tcx hir::Variant,
1518 g: &'tcx hir::Generics,
1519 item_id: hir::HirId) {
1520 if self.access_levels.is_reachable(v.node.id) {
1521 self.in_variant = true;
1522 intravisit::walk_variant(self, v, g, item_id);
1523 self.in_variant = false;
1527 fn visit_struct_field(&mut self, s: &'tcx hir::StructField) {
1528 if s.vis.node.is_pub() || self.in_variant {
1529 intravisit::walk_struct_field(self, s);
1533 // We don't need to introspect into these at all: an
1534 // expression/block context can't possibly contain exported things.
1535 // (Making them no-ops stops us from traversing the whole AST without
1536 // having to be super careful about our `walk_...` calls above.)
1537 fn visit_block(&mut self, _: &'tcx hir::Block) {}
1538 fn visit_expr(&mut self, _: &'tcx hir::Expr) {}
1541 ///////////////////////////////////////////////////////////////////////////////
1542 /// SearchInterfaceForPrivateItemsVisitor traverses an item's interface and
1543 /// finds any private components in it.
1544 /// PrivateItemsInPublicInterfacesVisitor ensures there are no private types
1545 /// and traits in public interfaces.
1546 ///////////////////////////////////////////////////////////////////////////////
1548 struct SearchInterfaceForPrivateItemsVisitor<'tcx> {
1550 item_id: hir::HirId,
1553 /// The visitor checks that each component type is at least this visible.
1554 required_visibility: ty::Visibility,
1555 has_pub_restricted: bool,
1556 has_old_errors: bool,
1560 impl SearchInterfaceForPrivateItemsVisitor<'tcx> {
1561 fn generics(&mut self) -> &mut Self {
1562 for param in &self.tcx.generics_of(self.item_def_id).params {
1564 GenericParamDefKind::Lifetime => {}
1565 GenericParamDefKind::Type { has_default, .. } => {
1567 self.visit(self.tcx.type_of(param.def_id));
1570 GenericParamDefKind::Const => {
1571 self.visit(self.tcx.type_of(param.def_id));
1578 fn predicates(&mut self) -> &mut Self {
1579 // N.B., we use `explicit_predicates_of` and not `predicates_of`
1580 // because we don't want to report privacy errors due to where
1581 // clauses that the compiler inferred. We only want to
1582 // consider the ones that the user wrote. This is important
1583 // for the inferred outlives rules; see
1584 // `src/test/ui/rfc-2093-infer-outlives/privacy.rs`.
1585 self.visit_predicates(self.tcx.explicit_predicates_of(self.item_def_id));
1589 fn ty(&mut self) -> &mut Self {
1590 self.visit(self.tcx.type_of(self.item_def_id));
1594 fn check_def_id(&mut self, def_id: DefId, kind: &str, descr: &dyn fmt::Display) -> bool {
1595 if self.leaks_private_dep(def_id) {
1596 self.tcx.lint_hir(lint::builtin::EXPORTED_PRIVATE_DEPENDENCIES,
1599 &format!("{} `{}` from private dependency '{}' in public \
1600 interface", kind, descr,
1601 self.tcx.crate_name(def_id.krate)));
1605 let hir_id = match self.tcx.hir().as_local_hir_id(def_id) {
1606 Some(hir_id) => hir_id,
1607 None => return false,
1610 let (vis, vis_span, vis_descr) = def_id_visibility(self.tcx, def_id);
1611 if !vis.is_at_least(self.required_visibility, self.tcx) {
1612 let msg = format!("{} {} `{}` in public interface", vis_descr, kind, descr);
1613 if self.has_pub_restricted || self.has_old_errors || self.in_assoc_ty {
1614 let mut err = if kind == "trait" {
1615 struct_span_err!(self.tcx.sess, self.span, E0445, "{}", msg)
1617 struct_span_err!(self.tcx.sess, self.span, E0446, "{}", msg)
1619 err.span_label(self.span, format!("can't leak {} {}", vis_descr, kind));
1620 err.span_label(vis_span, format!("`{}` declared as {}", descr, vis_descr));
1623 let err_code = if kind == "trait" { "E0445" } else { "E0446" };
1624 self.tcx.lint_hir(lint::builtin::PRIVATE_IN_PUBLIC, hir_id, self.span,
1625 &format!("{} (error {})", msg, err_code));
1633 /// An item is 'leaked' from a private dependency if all
1634 /// of the following are true:
1635 /// 1. It's contained within a public type
1636 /// 2. It comes from a private crate
1637 fn leaks_private_dep(&self, item_id: DefId) -> bool {
1638 let ret = self.required_visibility == ty::Visibility::Public &&
1639 self.tcx.is_private_dep(item_id.krate);
1641 log::debug!("leaks_private_dep(item_id={:?})={}", item_id, ret);
1646 impl DefIdVisitor<'tcx> for SearchInterfaceForPrivateItemsVisitor<'tcx> {
1647 fn tcx(&self) -> TyCtxt<'tcx> { self.tcx }
1648 fn visit_def_id(&mut self, def_id: DefId, kind: &str, descr: &dyn fmt::Display) -> bool {
1649 self.check_def_id(def_id, kind, descr)
1653 struct PrivateItemsInPublicInterfacesVisitor<'a, 'tcx> {
1655 has_pub_restricted: bool,
1656 old_error_set: &'a HirIdSet,
1659 impl<'a, 'tcx> PrivateItemsInPublicInterfacesVisitor<'a, 'tcx> {
1662 item_id: hir::HirId,
1663 required_visibility: ty::Visibility,
1664 ) -> SearchInterfaceForPrivateItemsVisitor<'tcx> {
1665 let mut has_old_errors = false;
1667 // Slow path taken only if there any errors in the crate.
1668 for &id in self.old_error_set {
1669 // Walk up the nodes until we find `item_id` (or we hit a root).
1673 has_old_errors = true;
1676 let parent = self.tcx.hir().get_parent_node(id);
1688 SearchInterfaceForPrivateItemsVisitor {
1691 item_def_id: self.tcx.hir().local_def_id(item_id),
1692 span: self.tcx.hir().span(item_id),
1693 required_visibility,
1694 has_pub_restricted: self.has_pub_restricted,
1700 fn check_assoc_item(
1703 assoc_item_kind: AssocItemKind,
1704 defaultness: hir::Defaultness,
1705 vis: ty::Visibility,
1707 let mut check = self.check(hir_id, vis);
1709 let (check_ty, is_assoc_ty) = match assoc_item_kind {
1710 AssocItemKind::Const | AssocItemKind::Method { .. } => (true, false),
1711 AssocItemKind::Type => (defaultness.has_value(), true),
1712 // `ty()` for existential types is the underlying type,
1713 // it's not a part of interface, so we skip it.
1714 AssocItemKind::Existential => (false, true),
1716 check.in_assoc_ty = is_assoc_ty;
1717 check.generics().predicates();
1724 impl<'a, 'tcx> Visitor<'tcx> for PrivateItemsInPublicInterfacesVisitor<'a, 'tcx> {
1725 fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> {
1726 NestedVisitorMap::OnlyBodies(&self.tcx.hir())
1729 fn visit_item(&mut self, item: &'tcx hir::Item) {
1731 let item_visibility = ty::Visibility::from_hir(&item.vis, item.hir_id, tcx);
1734 // Crates are always public.
1735 hir::ItemKind::ExternCrate(..) => {}
1736 // All nested items are checked by `visit_item`.
1737 hir::ItemKind::Mod(..) => {}
1738 // Checked in resolve.
1739 hir::ItemKind::Use(..) => {}
1741 hir::ItemKind::GlobalAsm(..) => {}
1742 // Subitems of these items have inherited publicity.
1743 hir::ItemKind::Const(..) | hir::ItemKind::Static(..) |
1744 hir::ItemKind::Fn(..) | hir::ItemKind::Ty(..) => {
1745 self.check(item.hir_id, item_visibility).generics().predicates().ty();
1747 hir::ItemKind::Existential(..) => {
1748 // `ty()` for existential types is the underlying type,
1749 // it's not a part of interface, so we skip it.
1750 self.check(item.hir_id, item_visibility).generics().predicates();
1752 hir::ItemKind::Trait(.., ref trait_item_refs) => {
1753 self.check(item.hir_id, item_visibility).generics().predicates();
1755 for trait_item_ref in trait_item_refs {
1756 self.check_assoc_item(
1757 trait_item_ref.id.hir_id,
1758 trait_item_ref.kind,
1759 trait_item_ref.defaultness,
1764 hir::ItemKind::TraitAlias(..) => {
1765 self.check(item.hir_id, item_visibility).generics().predicates();
1767 hir::ItemKind::Enum(ref def, _) => {
1768 self.check(item.hir_id, item_visibility).generics().predicates();
1770 for variant in &def.variants {
1771 for field in variant.node.data.fields() {
1772 self.check(field.hir_id, item_visibility).ty();
1776 // Subitems of foreign modules have their own publicity.
1777 hir::ItemKind::ForeignMod(ref foreign_mod) => {
1778 for foreign_item in &foreign_mod.items {
1779 let vis = ty::Visibility::from_hir(&foreign_item.vis, item.hir_id, tcx);
1780 self.check(foreign_item.hir_id, vis).generics().predicates().ty();
1783 // Subitems of structs and unions have their own publicity.
1784 hir::ItemKind::Struct(ref struct_def, _) |
1785 hir::ItemKind::Union(ref struct_def, _) => {
1786 self.check(item.hir_id, item_visibility).generics().predicates();
1788 for field in struct_def.fields() {
1789 let field_visibility = ty::Visibility::from_hir(&field.vis, item.hir_id, tcx);
1790 self.check(field.hir_id, min(item_visibility, field_visibility, tcx)).ty();
1793 // An inherent impl is public when its type is public
1794 // Subitems of inherent impls have their own publicity.
1795 // A trait impl is public when both its type and its trait are public
1796 // Subitems of trait impls have inherited publicity.
1797 hir::ItemKind::Impl(.., ref trait_ref, _, ref impl_item_refs) => {
1798 let impl_vis = ty::Visibility::of_impl(item.hir_id, tcx, &Default::default());
1799 self.check(item.hir_id, impl_vis).generics().predicates();
1800 for impl_item_ref in impl_item_refs {
1801 let impl_item = tcx.hir().impl_item(impl_item_ref.id);
1802 let impl_item_vis = if trait_ref.is_none() {
1803 min(ty::Visibility::from_hir(&impl_item.vis, item.hir_id, tcx),
1809 self.check_assoc_item(
1810 impl_item_ref.id.hir_id,
1812 impl_item_ref.defaultness,
1821 pub fn provide(providers: &mut Providers<'_>) {
1822 *providers = Providers {
1823 privacy_access_levels,
1824 check_private_in_public,
1830 fn check_mod_privacy(tcx: TyCtxt<'_>, module_def_id: DefId) {
1831 let empty_tables = ty::TypeckTables::empty(None);
1833 // Check privacy of names not checked in previous compilation stages.
1834 let mut visitor = NamePrivacyVisitor {
1836 tables: &empty_tables,
1837 current_item: hir::DUMMY_HIR_ID,
1838 empty_tables: &empty_tables,
1840 let (module, span, hir_id) = tcx.hir().get_module(module_def_id);
1842 intravisit::walk_mod(&mut visitor, module, hir_id);
1844 // Check privacy of explicitly written types and traits as well as
1845 // inferred types of expressions and patterns.
1846 let mut visitor = TypePrivacyVisitor {
1848 tables: &empty_tables,
1849 current_item: module_def_id,
1852 empty_tables: &empty_tables,
1854 intravisit::walk_mod(&mut visitor, module, hir_id);
1857 fn privacy_access_levels(tcx: TyCtxt<'_>, krate: CrateNum) -> &AccessLevels {
1858 assert_eq!(krate, LOCAL_CRATE);
1860 // Build up a set of all exported items in the AST. This is a set of all
1861 // items which are reachable from external crates based on visibility.
1862 let mut visitor = EmbargoVisitor {
1864 access_levels: Default::default(),
1865 prev_level: Some(AccessLevel::Public),
1869 intravisit::walk_crate(&mut visitor, tcx.hir().krate());
1870 if visitor.changed {
1871 visitor.changed = false;
1876 visitor.update(hir::CRATE_HIR_ID, Some(AccessLevel::Public));
1878 tcx.arena.alloc(visitor.access_levels)
1881 fn check_private_in_public(tcx: TyCtxt<'_>, krate: CrateNum) {
1882 assert_eq!(krate, LOCAL_CRATE);
1884 let access_levels = tcx.privacy_access_levels(LOCAL_CRATE);
1886 let krate = tcx.hir().krate();
1888 let mut visitor = ObsoleteVisiblePrivateTypesVisitor {
1890 access_levels: &access_levels,
1892 old_error_set: Default::default(),
1894 intravisit::walk_crate(&mut visitor, krate);
1896 let has_pub_restricted = {
1897 let mut pub_restricted_visitor = PubRestrictedVisitor {
1899 has_pub_restricted: false
1901 intravisit::walk_crate(&mut pub_restricted_visitor, krate);
1902 pub_restricted_visitor.has_pub_restricted
1905 // Check for private types and traits in public interfaces.
1906 let mut visitor = PrivateItemsInPublicInterfacesVisitor {
1909 old_error_set: &visitor.old_error_set,
1911 krate.visit_all_item_likes(&mut DeepVisitor::new(&mut visitor));
1914 __build_diagnostic_array! { librustc_privacy, DIAGNOSTICS }