1 #![doc(html_root_url = "https://doc.rust-lang.org/nightly/")]
3 #![deny(rust_2018_idioms)]
5 #![deny(unused_lifetimes)]
7 #![feature(in_band_lifetimes)]
9 #![feature(rustc_diagnostic_macros)]
11 #![recursion_limit="256"]
13 #[macro_use] extern crate syntax;
16 use rustc::hir::{self, Node, PatKind, AssocItemKind};
17 use rustc::hir::def::{Res, DefKind};
18 use rustc::hir::def_id::{CRATE_DEF_INDEX, LOCAL_CRATE, CrateNum, DefId};
19 use rustc::hir::intravisit::{self, Visitor, NestedVisitorMap};
20 use rustc::hir::itemlikevisit::DeepVisitor;
22 use rustc::middle::privacy::{AccessLevel, AccessLevels};
23 use rustc::ty::{self, TyCtxt, Ty, TraitRef, TypeFoldable, GenericParamDefKind};
24 use rustc::ty::fold::TypeVisitor;
25 use rustc::ty::query::Providers;
26 use rustc::ty::subst::InternalSubsts;
27 use rustc::util::nodemap::HirIdSet;
28 use rustc_data_structures::fx::FxHashSet;
29 use syntax::ast::Ident;
31 use syntax::symbol::{kw, sym};
34 use std::{cmp, fmt, mem};
35 use std::marker::PhantomData;
39 ////////////////////////////////////////////////////////////////////////////////
40 /// Generic infrastructure used to implement specific visitors below.
41 ////////////////////////////////////////////////////////////////////////////////
43 /// Implemented to visit all `DefId`s in a type.
44 /// Visiting `DefId`s is useful because visibilities and reachabilities are attached to them.
45 /// The idea is to visit "all components of a type", as documented in
46 /// https://github.com/rust-lang/rfcs/blob/master/text/2145-type-privacy.md#how-to-determine-visibility-of-a-type.
47 /// The default type visitor (`TypeVisitor`) does most of the job, but it has some shortcomings.
48 /// First, it doesn't have overridable `fn visit_trait_ref`, so we have to catch trait `DefId`s
49 /// manually. Second, it doesn't visit some type components like signatures of fn types, or traits
50 /// in `impl Trait`, see individual comments in `DefIdVisitorSkeleton::visit_ty`.
51 trait DefIdVisitor<'tcx> {
52 fn tcx(&self) -> TyCtxt<'tcx>;
53 fn shallow(&self) -> bool { false }
54 fn skip_assoc_tys(&self) -> bool { false }
55 fn visit_def_id(&mut self, def_id: DefId, kind: &str, descr: &dyn fmt::Display) -> bool;
57 /// Not overridden, but used to actually visit types and traits.
58 fn skeleton(&mut self) -> DefIdVisitorSkeleton<'_, 'tcx, Self> {
59 DefIdVisitorSkeleton {
61 visited_opaque_tys: Default::default(),
62 dummy: Default::default(),
65 fn visit(&mut self, ty_fragment: impl TypeFoldable<'tcx>) -> bool {
66 ty_fragment.visit_with(&mut self.skeleton())
68 fn visit_trait(&mut self, trait_ref: TraitRef<'tcx>) -> bool {
69 self.skeleton().visit_trait(trait_ref)
71 fn visit_predicates(&mut self, predicates: &ty::GenericPredicates<'tcx>) -> bool {
72 self.skeleton().visit_predicates(predicates)
76 struct DefIdVisitorSkeleton<'v, 'tcx, V>
78 V: DefIdVisitor<'tcx> + ?Sized,
80 def_id_visitor: &'v mut V,
81 visited_opaque_tys: FxHashSet<DefId>,
82 dummy: PhantomData<TyCtxt<'tcx>>,
85 impl<'tcx, V> DefIdVisitorSkeleton<'_, 'tcx, V>
87 V: DefIdVisitor<'tcx> + ?Sized,
89 fn visit_trait(&mut self, trait_ref: TraitRef<'tcx>) -> bool {
90 let TraitRef { def_id, substs } = trait_ref;
91 self.def_id_visitor.visit_def_id(def_id, "trait", &trait_ref) ||
92 (!self.def_id_visitor.shallow() && substs.visit_with(self))
95 fn visit_predicates(&mut self, predicates: &ty::GenericPredicates<'tcx>) -> bool {
96 let ty::GenericPredicates { parent: _, predicates } = predicates;
97 for (predicate, _span) in predicates {
99 ty::Predicate::Trait(poly_predicate) => {
100 let ty::TraitPredicate { trait_ref } = *poly_predicate.skip_binder();
101 if self.visit_trait(trait_ref) {
105 ty::Predicate::Projection(poly_predicate) => {
106 let ty::ProjectionPredicate { projection_ty, ty } =
107 *poly_predicate.skip_binder();
108 if ty.visit_with(self) {
111 if self.visit_trait(projection_ty.trait_ref(self.def_id_visitor.tcx())) {
115 ty::Predicate::TypeOutlives(poly_predicate) => {
116 let ty::OutlivesPredicate(ty, _region) = *poly_predicate.skip_binder();
117 if ty.visit_with(self) {
121 ty::Predicate::RegionOutlives(..) => {},
122 _ => bug!("unexpected predicate: {:?}", predicate),
129 impl<'tcx, V> TypeVisitor<'tcx> for DefIdVisitorSkeleton<'_, 'tcx, V>
131 V: DefIdVisitor<'tcx> + ?Sized,
133 fn visit_ty(&mut self, ty: Ty<'tcx>) -> bool {
134 let tcx = self.def_id_visitor.tcx();
135 // InternalSubsts are not visited here because they are visited below in `super_visit_with`.
137 ty::Adt(&ty::AdtDef { did: def_id, .. }, ..) |
138 ty::Foreign(def_id) |
139 ty::FnDef(def_id, ..) |
140 ty::Closure(def_id, ..) |
141 ty::Generator(def_id, ..) => {
142 if self.def_id_visitor.visit_def_id(def_id, "type", &ty) {
145 if self.def_id_visitor.shallow() {
148 // Default type visitor doesn't visit signatures of fn types.
149 // Something like `fn() -> Priv {my_func}` is considered a private type even if
150 // `my_func` is public, so we need to visit signatures.
151 if let ty::FnDef(..) = ty.sty {
152 if tcx.fn_sig(def_id).visit_with(self) {
156 // Inherent static methods don't have self type in substs.
157 // Something like `fn() {my_method}` type of the method
158 // `impl Pub<Priv> { pub fn my_method() {} }` is considered a private type,
159 // so we need to visit the self type additionally.
160 if let Some(assoc_item) = tcx.opt_associated_item(def_id) {
161 if let ty::ImplContainer(impl_def_id) = assoc_item.container {
162 if tcx.type_of(impl_def_id).visit_with(self) {
168 ty::Projection(proj) | ty::UnnormalizedProjection(proj) => {
169 if self.def_id_visitor.skip_assoc_tys() {
170 // Visitors searching for minimal visibility/reachability want to
171 // conservatively approximate associated types like `<Type as Trait>::Alias`
172 // as visible/reachable even if both `Type` and `Trait` are private.
173 // Ideally, associated types should be substituted in the same way as
174 // free type aliases, but this isn't done yet.
177 // This will also visit substs if necessary, so we don't need to recurse.
178 return self.visit_trait(proj.trait_ref(tcx));
180 ty::Dynamic(predicates, ..) => {
181 // All traits in the list are considered the "primary" part of the type
182 // and are visited by shallow visitors.
183 for predicate in *predicates.skip_binder() {
184 let trait_ref = match *predicate {
185 ty::ExistentialPredicate::Trait(trait_ref) => trait_ref,
186 ty::ExistentialPredicate::Projection(proj) => proj.trait_ref(tcx),
187 ty::ExistentialPredicate::AutoTrait(def_id) =>
188 ty::ExistentialTraitRef { def_id, substs: InternalSubsts::empty() },
190 let ty::ExistentialTraitRef { def_id, substs: _ } = trait_ref;
191 if self.def_id_visitor.visit_def_id(def_id, "trait", &trait_ref) {
196 ty::Opaque(def_id, ..) => {
197 // Skip repeated `Opaque`s to avoid infinite recursion.
198 if self.visited_opaque_tys.insert(def_id) {
199 // The intent is to treat `impl Trait1 + Trait2` identically to
200 // `dyn Trait1 + Trait2`. Therefore we ignore def-id of the opaque type itself
201 // (it either has no visibility, or its visibility is insignificant, like
202 // visibilities of type aliases) and recurse into predicates instead to go
203 // through the trait list (default type visitor doesn't visit those traits).
204 // All traits in the list are considered the "primary" part of the type
205 // and are visited by shallow visitors.
206 if self.visit_predicates(tcx.predicates_of(def_id)) {
211 // These types don't have their own def-ids (but may have subcomponents
212 // with def-ids that should be visited recursively).
213 ty::Bool | ty::Char | ty::Int(..) | ty::Uint(..) |
214 ty::Float(..) | ty::Str | ty::Never |
215 ty::Array(..) | ty::Slice(..) | ty::Tuple(..) |
216 ty::RawPtr(..) | ty::Ref(..) | ty::FnPtr(..) |
217 ty::Param(..) | ty::Error | ty::GeneratorWitness(..) => {}
218 ty::Bound(..) | ty::Placeholder(..) | ty::Infer(..) =>
219 bug!("unexpected type: {:?}", ty),
222 !self.def_id_visitor.shallow() && ty.super_visit_with(self)
226 fn def_id_visibility<'tcx>(
229 ) -> (ty::Visibility, Span, &'static str) {
230 match tcx.hir().as_local_hir_id(def_id) {
232 let vis = match tcx.hir().get(hir_id) {
233 Node::Item(item) => &item.vis,
234 Node::ForeignItem(foreign_item) => &foreign_item.vis,
235 Node::TraitItem(..) | Node::Variant(..) => {
236 return def_id_visibility(tcx, tcx.hir().get_parent_did(hir_id));
238 Node::ImplItem(impl_item) => {
239 match tcx.hir().get(tcx.hir().get_parent_item(hir_id)) {
240 Node::Item(item) => match &item.node {
241 hir::ItemKind::Impl(.., None, _, _) => &impl_item.vis,
242 hir::ItemKind::Impl(.., Some(trait_ref), _, _)
243 => return def_id_visibility(tcx, trait_ref.path.res.def_id()),
244 kind => bug!("unexpected item kind: {:?}", kind),
246 node => bug!("unexpected node kind: {:?}", node),
249 Node::Ctor(vdata) => {
250 let parent_hir_id = tcx.hir().get_parent_node(hir_id);
251 match tcx.hir().get(parent_hir_id) {
252 Node::Variant(..) => {
253 let parent_did = tcx.hir().local_def_id_from_hir_id(parent_hir_id);
254 let (mut ctor_vis, mut span, mut descr) = def_id_visibility(
258 let adt_def = tcx.adt_def(tcx.hir().get_parent_did(hir_id));
259 let ctor_did = tcx.hir().local_def_id_from_hir_id(
260 vdata.ctor_hir_id().unwrap());
261 let variant = adt_def.variant_with_ctor_id(ctor_did);
263 if variant.is_field_list_non_exhaustive() &&
264 ctor_vis == ty::Visibility::Public
266 ctor_vis = ty::Visibility::Restricted(
267 DefId::local(CRATE_DEF_INDEX));
268 let attrs = tcx.get_attrs(variant.def_id);
269 span = attr::find_by_name(&attrs, sym::non_exhaustive)
271 descr = "crate-visible";
274 return (ctor_vis, span, descr);
277 let item = match tcx.hir().get(parent_hir_id) {
278 Node::Item(item) => item,
279 node => bug!("unexpected node kind: {:?}", node),
281 let (mut ctor_vis, mut span, mut descr) =
282 (ty::Visibility::from_hir(&item.vis, parent_hir_id, tcx),
283 item.vis.span, item.vis.node.descr());
284 for field in vdata.fields() {
285 let field_vis = ty::Visibility::from_hir(&field.vis, hir_id, tcx);
286 if ctor_vis.is_at_least(field_vis, tcx) {
287 ctor_vis = field_vis;
288 span = field.vis.span;
289 descr = field.vis.node.descr();
293 // If the structure is marked as non_exhaustive then lower the
294 // visibility to within the crate.
295 if ctor_vis == ty::Visibility::Public {
297 tcx.adt_def(tcx.hir().get_parent_did(hir_id));
298 if adt_def.non_enum_variant().is_field_list_non_exhaustive() {
300 ty::Visibility::Restricted(DefId::local(CRATE_DEF_INDEX));
301 span = attr::find_by_name(&item.attrs, sym::non_exhaustive)
303 descr = "crate-visible";
307 return (ctor_vis, span, descr);
309 node => bug!("unexpected node kind: {:?}", node),
312 Node::Expr(expr) => {
313 return (ty::Visibility::Restricted(
314 tcx.hir().get_module_parent(expr.hir_id)),
315 expr.span, "private")
317 node => bug!("unexpected node kind: {:?}", node)
319 (ty::Visibility::from_hir(vis, hir_id, tcx), vis.span, vis.node.descr())
322 let vis = tcx.visibility(def_id);
323 let descr = if vis == ty::Visibility::Public { "public" } else { "private" };
324 (vis, tcx.def_span(def_id), descr)
329 // Set the correct `TypeckTables` for the given `item_id` (or an empty table if
330 // there is no `TypeckTables` for the item).
331 fn item_tables<'a, 'tcx>(
334 empty_tables: &'a ty::TypeckTables<'tcx>,
335 ) -> &'a ty::TypeckTables<'tcx> {
336 let def_id = tcx.hir().local_def_id_from_hir_id(hir_id);
337 if tcx.has_typeck_tables(def_id) { tcx.typeck_tables_of(def_id) } else { empty_tables }
340 fn min<'tcx>(vis1: ty::Visibility, vis2: ty::Visibility, tcx: TyCtxt<'tcx>) -> ty::Visibility {
341 if vis1.is_at_least(vis2, tcx) { vis2 } else { vis1 }
344 ////////////////////////////////////////////////////////////////////////////////
345 /// Visitor used to determine if pub(restricted) is used anywhere in the crate.
347 /// This is done so that `private_in_public` warnings can be turned into hard errors
348 /// in crates that have been updated to use pub(restricted).
349 ////////////////////////////////////////////////////////////////////////////////
350 struct PubRestrictedVisitor<'tcx> {
352 has_pub_restricted: bool,
355 impl Visitor<'tcx> for PubRestrictedVisitor<'tcx> {
356 fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> {
357 NestedVisitorMap::All(&self.tcx.hir())
359 fn visit_vis(&mut self, vis: &'tcx hir::Visibility) {
360 self.has_pub_restricted = self.has_pub_restricted || vis.node.is_pub_restricted();
364 ////////////////////////////////////////////////////////////////////////////////
365 /// Visitor used to determine impl visibility and reachability.
366 ////////////////////////////////////////////////////////////////////////////////
368 struct FindMin<'a, 'tcx, VL: VisibilityLike> {
370 access_levels: &'a AccessLevels,
374 impl<'a, 'tcx, VL: VisibilityLike> DefIdVisitor<'tcx> for FindMin<'a, 'tcx, VL> {
375 fn tcx(&self) -> TyCtxt<'tcx> { self.tcx }
376 fn shallow(&self) -> bool { VL::SHALLOW }
377 fn skip_assoc_tys(&self) -> bool { true }
378 fn visit_def_id(&mut self, def_id: DefId, _kind: &str, _descr: &dyn fmt::Display) -> bool {
379 self.min = VL::new_min(self, def_id);
384 trait VisibilityLike: Sized {
386 const SHALLOW: bool = false;
387 fn new_min<'a, 'tcx>(find: &FindMin<'a, 'tcx, Self>, def_id: DefId) -> Self;
389 // Returns an over-approximation (`skip_assoc_tys` = true) of visibility due to
390 // associated types for which we can't determine visibility precisely.
391 fn of_impl<'a, 'tcx>(
394 access_levels: &'a AccessLevels,
396 let mut find = FindMin { tcx, access_levels, min: Self::MAX };
397 let def_id = tcx.hir().local_def_id_from_hir_id(hir_id);
398 find.visit(tcx.type_of(def_id));
399 if let Some(trait_ref) = tcx.impl_trait_ref(def_id) {
400 find.visit_trait(trait_ref);
405 impl VisibilityLike for ty::Visibility {
406 const MAX: Self = ty::Visibility::Public;
407 fn new_min<'a, 'tcx>(find: &FindMin<'a, 'tcx, Self>, def_id: DefId) -> Self {
408 min(def_id_visibility(find.tcx, def_id).0, find.min, find.tcx)
411 impl VisibilityLike for Option<AccessLevel> {
412 const MAX: Self = Some(AccessLevel::Public);
413 // Type inference is very smart sometimes.
414 // It can make an impl reachable even some components of its type or trait are unreachable.
415 // E.g. methods of `impl ReachableTrait<UnreachableTy> for ReachableTy<UnreachableTy> { ... }`
416 // can be usable from other crates (#57264). So we skip substs when calculating reachability
417 // and consider an impl reachable if its "shallow" type and trait are reachable.
419 // The assumption we make here is that type-inference won't let you use an impl without knowing
420 // both "shallow" version of its self type and "shallow" version of its trait if it exists
421 // (which require reaching the `DefId`s in them).
422 const SHALLOW: bool = true;
423 fn new_min<'a, 'tcx>(find: &FindMin<'a, 'tcx, Self>, def_id: DefId) -> Self {
424 cmp::min(if let Some(hir_id) = find.tcx.hir().as_local_hir_id(def_id) {
425 find.access_levels.map.get(&hir_id).cloned()
432 ////////////////////////////////////////////////////////////////////////////////
433 /// The embargo visitor, used to determine the exports of the AST.
434 ////////////////////////////////////////////////////////////////////////////////
436 struct EmbargoVisitor<'tcx> {
439 // Accessibility levels for reachable nodes.
440 access_levels: AccessLevels,
441 // Previous accessibility level; `None` means unreachable.
442 prev_level: Option<AccessLevel>,
443 // Has something changed in the level map?
447 struct ReachEverythingInTheInterfaceVisitor<'a, 'tcx> {
448 access_level: Option<AccessLevel>,
450 ev: &'a mut EmbargoVisitor<'tcx>,
453 impl EmbargoVisitor<'tcx> {
454 fn get(&self, id: hir::HirId) -> Option<AccessLevel> {
455 self.access_levels.map.get(&id).cloned()
458 // Updates node level and returns the updated level.
459 fn update(&mut self, id: hir::HirId, level: Option<AccessLevel>) -> Option<AccessLevel> {
460 let old_level = self.get(id);
461 // Accessibility levels can only grow.
462 if level > old_level {
463 self.access_levels.map.insert(id, level.unwrap());
474 access_level: Option<AccessLevel>,
475 ) -> ReachEverythingInTheInterfaceVisitor<'_, 'tcx> {
476 ReachEverythingInTheInterfaceVisitor {
477 access_level: cmp::min(access_level, Some(AccessLevel::Reachable)),
478 item_def_id: self.tcx.hir().local_def_id_from_hir_id(item_id),
484 /// Given the path segments of a `ItemKind::Use`, then we need
485 /// to update the visibility of the intermediate use so that it isn't linted
486 /// by `unreachable_pub`.
488 /// This isn't trivial as `path.res` has the `DefId` of the eventual target
489 /// of the use statement not of the next intermediate use statement.
491 /// To do this, consider the last two segments of the path to our intermediate
492 /// use statement. We expect the penultimate segment to be a module and the
493 /// last segment to be the name of the item we are exporting. We can then
494 /// look at the items contained in the module for the use statement with that
495 /// name and update that item's visibility.
497 /// FIXME: This solution won't work with glob imports and doesn't respect
498 /// namespaces. See <https://github.com/rust-lang/rust/pull/57922#discussion_r251234202>.
499 fn update_visibility_of_intermediate_use_statements(&mut self, segments: &[hir::PathSegment]) {
500 if let Some([module, segment]) = segments.rchunks_exact(2).next() {
501 if let Some(item) = module.res
502 .and_then(|res| res.mod_def_id())
503 .and_then(|def_id| self.tcx.hir().as_local_hir_id(def_id))
504 .map(|module_hir_id| self.tcx.hir().expect_item(module_hir_id))
506 if let hir::ItemKind::Mod(m) = &item.node {
507 for item_id in m.item_ids.as_ref() {
508 let item = self.tcx.hir().expect_item(item_id.id);
509 let def_id = self.tcx.hir().local_def_id_from_hir_id(item_id.id);
510 if !self.tcx.hygienic_eq(segment.ident, item.ident, def_id) { continue; }
511 if let hir::ItemKind::Use(..) = item.node {
512 self.update(item.hir_id, Some(AccessLevel::Exported));
521 impl Visitor<'tcx> for EmbargoVisitor<'tcx> {
522 /// We want to visit items in the context of their containing
523 /// module and so forth, so supply a crate for doing a deep walk.
524 fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> {
525 NestedVisitorMap::All(&self.tcx.hir())
528 fn visit_item(&mut self, item: &'tcx hir::Item) {
529 let inherited_item_level = match item.node {
530 hir::ItemKind::Impl(..) =>
531 Option::<AccessLevel>::of_impl(item.hir_id, self.tcx, &self.access_levels),
532 // Foreign modules inherit level from parents.
533 hir::ItemKind::ForeignMod(..) => self.prev_level,
534 // Other `pub` items inherit levels from parents.
535 hir::ItemKind::Const(..) | hir::ItemKind::Enum(..) | hir::ItemKind::ExternCrate(..) |
536 hir::ItemKind::GlobalAsm(..) | hir::ItemKind::Fn(..) | hir::ItemKind::Mod(..) |
537 hir::ItemKind::Static(..) | hir::ItemKind::Struct(..) |
538 hir::ItemKind::Trait(..) | hir::ItemKind::TraitAlias(..) |
539 hir::ItemKind::Existential(..) |
540 hir::ItemKind::Ty(..) | hir::ItemKind::Union(..) | hir::ItemKind::Use(..) => {
541 if item.vis.node.is_pub() { self.prev_level } else { None }
545 // Update level of the item itself.
546 let item_level = self.update(item.hir_id, inherited_item_level);
548 // Update levels of nested things.
550 hir::ItemKind::Enum(ref def, _) => {
551 for variant in &def.variants {
552 let variant_level = self.update(variant.node.id, item_level);
553 if let Some(ctor_hir_id) = variant.node.data.ctor_hir_id() {
554 self.update(ctor_hir_id, item_level);
556 for field in variant.node.data.fields() {
557 self.update(field.hir_id, variant_level);
561 hir::ItemKind::Impl(.., ref trait_ref, _, ref impl_item_refs) => {
562 for impl_item_ref in impl_item_refs {
563 if trait_ref.is_some() || impl_item_ref.vis.node.is_pub() {
564 self.update(impl_item_ref.id.hir_id, item_level);
568 hir::ItemKind::Trait(.., ref trait_item_refs) => {
569 for trait_item_ref in trait_item_refs {
570 self.update(trait_item_ref.id.hir_id, item_level);
573 hir::ItemKind::Struct(ref def, _) | hir::ItemKind::Union(ref def, _) => {
574 if let Some(ctor_hir_id) = def.ctor_hir_id() {
575 self.update(ctor_hir_id, item_level);
577 for field in def.fields() {
578 if field.vis.node.is_pub() {
579 self.update(field.hir_id, item_level);
583 hir::ItemKind::ForeignMod(ref foreign_mod) => {
584 for foreign_item in &foreign_mod.items {
585 if foreign_item.vis.node.is_pub() {
586 self.update(foreign_item.hir_id, item_level);
590 hir::ItemKind::Existential(..) |
591 hir::ItemKind::Use(..) |
592 hir::ItemKind::Static(..) |
593 hir::ItemKind::Const(..) |
594 hir::ItemKind::GlobalAsm(..) |
595 hir::ItemKind::Ty(..) |
596 hir::ItemKind::Mod(..) |
597 hir::ItemKind::TraitAlias(..) |
598 hir::ItemKind::Fn(..) |
599 hir::ItemKind::ExternCrate(..) => {}
602 // Mark all items in interfaces of reachable items as reachable.
604 // The interface is empty.
605 hir::ItemKind::ExternCrate(..) => {}
606 // All nested items are checked by `visit_item`.
607 hir::ItemKind::Mod(..) => {}
608 // Re-exports are handled in `visit_mod`. However, in order to avoid looping over
609 // all of the items of a mod in `visit_mod` looking for use statements, we handle
610 // making sure that intermediate use statements have their visibilities updated here.
611 hir::ItemKind::Use(ref path, _) => {
612 if item_level.is_some() {
613 self.update_visibility_of_intermediate_use_statements(path.segments.as_ref());
616 // The interface is empty.
617 hir::ItemKind::GlobalAsm(..) => {}
618 hir::ItemKind::Existential(..) => {
619 // FIXME: This is some serious pessimization intended to workaround deficiencies
620 // in the reachability pass (`middle/reachable.rs`). Types are marked as link-time
621 // reachable if they are returned via `impl Trait`, even from private functions.
622 let exist_level = cmp::max(item_level, Some(AccessLevel::ReachableFromImplTrait));
623 self.reach(item.hir_id, exist_level).generics().predicates().ty();
626 hir::ItemKind::Const(..) | hir::ItemKind::Static(..) |
627 hir::ItemKind::Fn(..) | hir::ItemKind::Ty(..) => {
628 if item_level.is_some() {
629 self.reach(item.hir_id, item_level).generics().predicates().ty();
632 hir::ItemKind::Trait(.., ref trait_item_refs) => {
633 if item_level.is_some() {
634 self.reach(item.hir_id, item_level).generics().predicates();
636 for trait_item_ref in trait_item_refs {
637 let mut reach = self.reach(trait_item_ref.id.hir_id, item_level);
638 reach.generics().predicates();
640 if trait_item_ref.kind == AssocItemKind::Type &&
641 !trait_item_ref.defaultness.has_value() {
649 hir::ItemKind::TraitAlias(..) => {
650 if item_level.is_some() {
651 self.reach(item.hir_id, item_level).generics().predicates();
654 // Visit everything except for private impl items.
655 hir::ItemKind::Impl(.., ref impl_item_refs) => {
656 if item_level.is_some() {
657 self.reach(item.hir_id, item_level).generics().predicates().ty().trait_ref();
659 for impl_item_ref in impl_item_refs {
660 let impl_item_level = self.get(impl_item_ref.id.hir_id);
661 if impl_item_level.is_some() {
662 self.reach(impl_item_ref.id.hir_id, impl_item_level)
663 .generics().predicates().ty();
669 // Visit everything, but enum variants have their own levels.
670 hir::ItemKind::Enum(ref def, _) => {
671 if item_level.is_some() {
672 self.reach(item.hir_id, item_level).generics().predicates();
674 for variant in &def.variants {
675 let variant_level = self.get(variant.node.id);
676 if variant_level.is_some() {
677 for field in variant.node.data.fields() {
678 self.reach(field.hir_id, variant_level).ty();
680 // Corner case: if the variant is reachable, but its
681 // enum is not, make the enum reachable as well.
682 self.update(item.hir_id, variant_level);
686 // Visit everything, but foreign items have their own levels.
687 hir::ItemKind::ForeignMod(ref foreign_mod) => {
688 for foreign_item in &foreign_mod.items {
689 let foreign_item_level = self.get(foreign_item.hir_id);
690 if foreign_item_level.is_some() {
691 self.reach(foreign_item.hir_id, foreign_item_level)
692 .generics().predicates().ty();
696 // Visit everything except for private fields.
697 hir::ItemKind::Struct(ref struct_def, _) |
698 hir::ItemKind::Union(ref struct_def, _) => {
699 if item_level.is_some() {
700 self.reach(item.hir_id, item_level).generics().predicates();
701 for field in struct_def.fields() {
702 let field_level = self.get(field.hir_id);
703 if field_level.is_some() {
704 self.reach(field.hir_id, field_level).ty();
711 let orig_level = mem::replace(&mut self.prev_level, item_level);
712 intravisit::walk_item(self, item);
713 self.prev_level = orig_level;
716 fn visit_block(&mut self, b: &'tcx hir::Block) {
717 // Blocks can have public items, for example impls, but they always
718 // start as completely private regardless of publicity of a function,
719 // constant, type, field, etc., in which this block resides.
720 let orig_level = mem::replace(&mut self.prev_level, None);
721 intravisit::walk_block(self, b);
722 self.prev_level = orig_level;
725 fn visit_mod(&mut self, m: &'tcx hir::Mod, _sp: Span, id: hir::HirId) {
726 // This code is here instead of in visit_item so that the
727 // crate module gets processed as well.
728 if self.prev_level.is_some() {
729 let def_id = self.tcx.hir().local_def_id_from_hir_id(id);
730 if let Some(exports) = self.tcx.module_exports(def_id) {
731 for export in exports.iter() {
732 if export.vis == ty::Visibility::Public {
733 if let Some(def_id) = export.res.opt_def_id() {
734 if let Some(hir_id) = self.tcx.hir().as_local_hir_id(def_id) {
735 self.update(hir_id, Some(AccessLevel::Exported));
743 intravisit::walk_mod(self, m, id);
746 fn visit_macro_def(&mut self, md: &'tcx hir::MacroDef) {
748 self.update(md.hir_id, Some(AccessLevel::Public));
752 let module_did = ty::DefIdTree::parent(
754 self.tcx.hir().local_def_id_from_hir_id(md.hir_id)
756 let mut module_id = self.tcx.hir().as_local_hir_id(module_did).unwrap();
757 let level = if md.vis.node.is_pub() { self.get(module_id) } else { None };
758 let level = self.update(md.hir_id, level);
764 let module = if module_id == hir::CRATE_HIR_ID {
765 &self.tcx.hir().krate().module
766 } else if let hir::ItemKind::Mod(ref module) =
767 self.tcx.hir().expect_item(module_id).node {
772 for id in &module.item_ids {
773 self.update(id.id, level);
775 let def_id = self.tcx.hir().local_def_id_from_hir_id(module_id);
776 if let Some(exports) = self.tcx.module_exports(def_id) {
777 for export in exports.iter() {
778 if let Some(hir_id) = self.tcx.hir().as_local_hir_id(export.res.def_id()) {
779 self.update(hir_id, level);
784 if module_id == hir::CRATE_HIR_ID {
787 module_id = self.tcx.hir().get_parent_node(module_id);
792 impl ReachEverythingInTheInterfaceVisitor<'_, 'tcx> {
793 fn generics(&mut self) -> &mut Self {
794 for param in &self.ev.tcx.generics_of(self.item_def_id).params {
796 GenericParamDefKind::Lifetime => {}
797 GenericParamDefKind::Type { has_default, .. } => {
799 self.visit(self.ev.tcx.type_of(param.def_id));
802 GenericParamDefKind::Const => {
803 self.visit(self.ev.tcx.type_of(param.def_id));
810 fn predicates(&mut self) -> &mut Self {
811 self.visit_predicates(self.ev.tcx.predicates_of(self.item_def_id));
815 fn ty(&mut self) -> &mut Self {
816 self.visit(self.ev.tcx.type_of(self.item_def_id));
820 fn trait_ref(&mut self) -> &mut Self {
821 if let Some(trait_ref) = self.ev.tcx.impl_trait_ref(self.item_def_id) {
822 self.visit_trait(trait_ref);
828 impl DefIdVisitor<'tcx> for ReachEverythingInTheInterfaceVisitor<'_, 'tcx> {
829 fn tcx(&self) -> TyCtxt<'tcx> { self.ev.tcx }
830 fn visit_def_id(&mut self, def_id: DefId, _kind: &str, _descr: &dyn fmt::Display) -> bool {
831 if let Some(hir_id) = self.ev.tcx.hir().as_local_hir_id(def_id) {
832 self.ev.update(hir_id, self.access_level);
838 //////////////////////////////////////////////////////////////////////////////////////
839 /// Name privacy visitor, checks privacy and reports violations.
840 /// Most of name privacy checks are performed during the main resolution phase,
841 /// or later in type checking when field accesses and associated items are resolved.
842 /// This pass performs remaining checks for fields in struct expressions and patterns.
843 //////////////////////////////////////////////////////////////////////////////////////
845 struct NamePrivacyVisitor<'a, 'tcx> {
847 tables: &'a ty::TypeckTables<'tcx>,
848 current_item: hir::HirId,
849 empty_tables: &'a ty::TypeckTables<'tcx>,
852 impl<'a, 'tcx> NamePrivacyVisitor<'a, 'tcx> {
853 // Checks that a field in a struct constructor (expression or pattern) is accessible.
854 fn check_field(&mut self,
855 use_ctxt: Span, // syntax context of the field name at the use site
856 span: Span, // span of the field pattern, e.g., `x: 0`
857 def: &'tcx ty::AdtDef, // definition of the struct or enum
858 field: &'tcx ty::FieldDef) { // definition of the field
859 let ident = Ident::new(kw::Invalid, use_ctxt);
860 let current_hir = self.current_item;
861 let def_id = self.tcx.adjust_ident_and_get_scope(ident, def.did, current_hir).1;
862 if !def.is_enum() && !field.vis.is_accessible_from(def_id, self.tcx) {
863 struct_span_err!(self.tcx.sess, span, E0451, "field `{}` of {} `{}` is private",
864 field.ident, def.variant_descr(), self.tcx.def_path_str(def.did))
865 .span_label(span, format!("field `{}` is private", field.ident))
871 impl<'a, 'tcx> Visitor<'tcx> for NamePrivacyVisitor<'a, 'tcx> {
872 /// We want to visit items in the context of their containing
873 /// module and so forth, so supply a crate for doing a deep walk.
874 fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> {
875 NestedVisitorMap::All(&self.tcx.hir())
878 fn visit_mod(&mut self, _m: &'tcx hir::Mod, _s: Span, _n: hir::HirId) {
879 // Don't visit nested modules, since we run a separate visitor walk
880 // for each module in `privacy_access_levels`
883 fn visit_nested_body(&mut self, body: hir::BodyId) {
884 let orig_tables = mem::replace(&mut self.tables, self.tcx.body_tables(body));
885 let body = self.tcx.hir().body(body);
886 self.visit_body(body);
887 self.tables = orig_tables;
890 fn visit_item(&mut self, item: &'tcx hir::Item) {
891 let orig_current_item = mem::replace(&mut self.current_item, item.hir_id);
893 mem::replace(&mut self.tables, item_tables(self.tcx, item.hir_id, self.empty_tables));
894 intravisit::walk_item(self, item);
895 self.current_item = orig_current_item;
896 self.tables = orig_tables;
899 fn visit_trait_item(&mut self, ti: &'tcx hir::TraitItem) {
901 mem::replace(&mut self.tables, item_tables(self.tcx, ti.hir_id, self.empty_tables));
902 intravisit::walk_trait_item(self, ti);
903 self.tables = orig_tables;
906 fn visit_impl_item(&mut self, ii: &'tcx hir::ImplItem) {
908 mem::replace(&mut self.tables, item_tables(self.tcx, ii.hir_id, self.empty_tables));
909 intravisit::walk_impl_item(self, ii);
910 self.tables = orig_tables;
913 fn visit_expr(&mut self, expr: &'tcx hir::Expr) {
915 hir::ExprKind::Struct(ref qpath, ref fields, ref base) => {
916 let res = self.tables.qpath_res(qpath, expr.hir_id);
917 let adt = self.tables.expr_ty(expr).ty_adt_def().unwrap();
918 let variant = adt.variant_of_res(res);
919 if let Some(ref base) = *base {
920 // If the expression uses FRU we need to make sure all the unmentioned fields
921 // are checked for privacy (RFC 736). Rather than computing the set of
922 // unmentioned fields, just check them all.
923 for (vf_index, variant_field) in variant.fields.iter().enumerate() {
924 let field = fields.iter().find(|f| {
925 self.tcx.field_index(f.hir_id, self.tables) == vf_index
927 let (use_ctxt, span) = match field {
928 Some(field) => (field.ident.span, field.span),
929 None => (base.span, base.span),
931 self.check_field(use_ctxt, span, adt, variant_field);
934 for field in fields {
935 let use_ctxt = field.ident.span;
936 let index = self.tcx.field_index(field.hir_id, self.tables);
937 self.check_field(use_ctxt, field.span, adt, &variant.fields[index]);
944 intravisit::walk_expr(self, expr);
947 fn visit_pat(&mut self, pat: &'tcx hir::Pat) {
949 PatKind::Struct(ref qpath, ref fields, _) => {
950 let res = self.tables.qpath_res(qpath, pat.hir_id);
951 let adt = self.tables.pat_ty(pat).ty_adt_def().unwrap();
952 let variant = adt.variant_of_res(res);
953 for field in fields {
954 let use_ctxt = field.node.ident.span;
955 let index = self.tcx.field_index(field.node.hir_id, self.tables);
956 self.check_field(use_ctxt, field.span, adt, &variant.fields[index]);
962 intravisit::walk_pat(self, pat);
966 ////////////////////////////////////////////////////////////////////////////////////////////
967 /// Type privacy visitor, checks types for privacy and reports violations.
968 /// Both explicitly written types and inferred types of expressions and patters are checked.
969 /// Checks are performed on "semantic" types regardless of names and their hygiene.
970 ////////////////////////////////////////////////////////////////////////////////////////////
972 struct TypePrivacyVisitor<'a, 'tcx> {
974 tables: &'a ty::TypeckTables<'tcx>,
978 empty_tables: &'a ty::TypeckTables<'tcx>,
981 impl<'a, 'tcx> TypePrivacyVisitor<'a, 'tcx> {
982 fn item_is_accessible(&self, did: DefId) -> bool {
983 def_id_visibility(self.tcx, did).0.is_accessible_from(self.current_item, self.tcx)
986 // Take node-id of an expression or pattern and check its type for privacy.
987 fn check_expr_pat_type(&mut self, id: hir::HirId, span: Span) -> bool {
989 if self.visit(self.tables.node_type(id)) || self.visit(self.tables.node_substs(id)) {
992 if let Some(adjustments) = self.tables.adjustments().get(id) {
993 for adjustment in adjustments {
994 if self.visit(adjustment.target) {
1002 fn check_def_id(&mut self, def_id: DefId, kind: &str, descr: &dyn fmt::Display) -> bool {
1003 let is_error = !self.item_is_accessible(def_id);
1005 self.tcx.sess.span_err(self.span, &format!("{} `{}` is private", kind, descr));
1011 impl<'a, 'tcx> Visitor<'tcx> for TypePrivacyVisitor<'a, 'tcx> {
1012 /// We want to visit items in the context of their containing
1013 /// module and so forth, so supply a crate for doing a deep walk.
1014 fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> {
1015 NestedVisitorMap::All(&self.tcx.hir())
1018 fn visit_mod(&mut self, _m: &'tcx hir::Mod, _s: Span, _n: hir::HirId) {
1019 // Don't visit nested modules, since we run a separate visitor walk
1020 // for each module in `privacy_access_levels`
1023 fn visit_nested_body(&mut self, body: hir::BodyId) {
1024 let orig_tables = mem::replace(&mut self.tables, self.tcx.body_tables(body));
1025 let orig_in_body = mem::replace(&mut self.in_body, true);
1026 let body = self.tcx.hir().body(body);
1027 self.visit_body(body);
1028 self.tables = orig_tables;
1029 self.in_body = orig_in_body;
1032 fn visit_ty(&mut self, hir_ty: &'tcx hir::Ty) {
1033 self.span = hir_ty.span;
1036 if self.visit(self.tables.node_type(hir_ty.hir_id)) {
1040 // Types in signatures.
1041 // FIXME: This is very ineffective. Ideally each HIR type should be converted
1042 // into a semantic type only once and the result should be cached somehow.
1043 if self.visit(rustc_typeck::hir_ty_to_ty(self.tcx, hir_ty)) {
1048 intravisit::walk_ty(self, hir_ty);
1051 fn visit_trait_ref(&mut self, trait_ref: &'tcx hir::TraitRef) {
1052 self.span = trait_ref.path.span;
1054 // Avoid calling `hir_trait_to_predicates` in bodies, it will ICE.
1055 // The traits' privacy in bodies is already checked as a part of trait object types.
1056 let (principal, bounds) = rustc_typeck::hir_trait_to_predicates(self.tcx, trait_ref);
1057 if self.visit_trait(*principal.skip_binder()) {
1060 for (poly_predicate, _) in bounds.projection_bounds {
1062 if self.visit(poly_predicate.skip_binder().ty) ||
1063 self.visit_trait(poly_predicate.skip_binder().projection_ty.trait_ref(tcx)) {
1069 intravisit::walk_trait_ref(self, trait_ref);
1072 // Check types of expressions
1073 fn visit_expr(&mut self, expr: &'tcx hir::Expr) {
1074 if self.check_expr_pat_type(expr.hir_id, expr.span) {
1075 // Do not check nested expressions if the error already happened.
1079 hir::ExprKind::Assign(.., ref rhs) | hir::ExprKind::Match(ref rhs, ..) => {
1080 // Do not report duplicate errors for `x = y` and `match x { ... }`.
1081 if self.check_expr_pat_type(rhs.hir_id, rhs.span) {
1085 hir::ExprKind::MethodCall(_, span, _) => {
1086 // Method calls have to be checked specially.
1088 if let Some(def_id) = self.tables.type_dependent_def_id(expr.hir_id) {
1089 if self.visit(self.tcx.type_of(def_id)) {
1093 self.tcx.sess.delay_span_bug(expr.span,
1094 "no type-dependent def for method call");
1100 intravisit::walk_expr(self, expr);
1103 // Prohibit access to associated items with insufficient nominal visibility.
1105 // Additionally, until better reachability analysis for macros 2.0 is available,
1106 // we prohibit access to private statics from other crates, this allows to give
1107 // more code internal visibility at link time. (Access to private functions
1108 // is already prohibited by type privacy for function types.)
1109 fn visit_qpath(&mut self, qpath: &'tcx hir::QPath, id: hir::HirId, span: Span) {
1110 let def = match self.tables.qpath_res(qpath, id) {
1111 Res::Def(kind, def_id) => Some((kind, def_id)),
1114 let def = def.filter(|(kind, _)| {
1117 | DefKind::AssocConst
1119 | DefKind::AssocExistential
1120 | DefKind::Static => true,
1124 if let Some((kind, def_id)) = def {
1125 let is_local_static = if let DefKind::Static = kind {
1128 if !self.item_is_accessible(def_id) && !is_local_static {
1129 let name = match *qpath {
1130 hir::QPath::Resolved(_, ref path) => path.to_string(),
1131 hir::QPath::TypeRelative(_, ref segment) => segment.ident.to_string(),
1133 let msg = format!("{} `{}` is private", kind.descr(), name);
1134 self.tcx.sess.span_err(span, &msg);
1139 intravisit::walk_qpath(self, qpath, id, span);
1142 // Check types of patterns.
1143 fn visit_pat(&mut self, pattern: &'tcx hir::Pat) {
1144 if self.check_expr_pat_type(pattern.hir_id, pattern.span) {
1145 // Do not check nested patterns if the error already happened.
1149 intravisit::walk_pat(self, pattern);
1152 fn visit_local(&mut self, local: &'tcx hir::Local) {
1153 if let Some(ref init) = local.init {
1154 if self.check_expr_pat_type(init.hir_id, init.span) {
1155 // Do not report duplicate errors for `let x = y`.
1160 intravisit::walk_local(self, local);
1163 // Check types in item interfaces.
1164 fn visit_item(&mut self, item: &'tcx hir::Item) {
1165 let orig_current_item = mem::replace(&mut self.current_item,
1166 self.tcx.hir().local_def_id_from_hir_id(item.hir_id));
1167 let orig_in_body = mem::replace(&mut self.in_body, false);
1169 mem::replace(&mut self.tables, item_tables(self.tcx, item.hir_id, self.empty_tables));
1170 intravisit::walk_item(self, item);
1171 self.tables = orig_tables;
1172 self.in_body = orig_in_body;
1173 self.current_item = orig_current_item;
1176 fn visit_trait_item(&mut self, ti: &'tcx hir::TraitItem) {
1178 mem::replace(&mut self.tables, item_tables(self.tcx, ti.hir_id, self.empty_tables));
1179 intravisit::walk_trait_item(self, ti);
1180 self.tables = orig_tables;
1183 fn visit_impl_item(&mut self, ii: &'tcx hir::ImplItem) {
1185 mem::replace(&mut self.tables, item_tables(self.tcx, ii.hir_id, self.empty_tables));
1186 intravisit::walk_impl_item(self, ii);
1187 self.tables = orig_tables;
1191 impl DefIdVisitor<'tcx> for TypePrivacyVisitor<'a, 'tcx> {
1192 fn tcx(&self) -> TyCtxt<'tcx> { self.tcx }
1193 fn visit_def_id(&mut self, def_id: DefId, kind: &str, descr: &dyn fmt::Display) -> bool {
1194 self.check_def_id(def_id, kind, descr)
1198 ///////////////////////////////////////////////////////////////////////////////
1199 /// Obsolete visitors for checking for private items in public interfaces.
1200 /// These visitors are supposed to be kept in frozen state and produce an
1201 /// "old error node set". For backward compatibility the new visitor reports
1202 /// warnings instead of hard errors when the erroneous node is not in this old set.
1203 ///////////////////////////////////////////////////////////////////////////////
1205 struct ObsoleteVisiblePrivateTypesVisitor<'a, 'tcx> {
1207 access_levels: &'a AccessLevels,
1209 // Set of errors produced by this obsolete visitor.
1210 old_error_set: HirIdSet,
1213 struct ObsoleteCheckTypeForPrivatenessVisitor<'a, 'b, 'tcx> {
1214 inner: &'a ObsoleteVisiblePrivateTypesVisitor<'b, 'tcx>,
1215 /// Whether the type refers to private types.
1216 contains_private: bool,
1217 /// Whether we've recurred at all (i.e., if we're pointing at the
1218 /// first type on which `visit_ty` was called).
1219 at_outer_type: bool,
1220 /// Whether that first type is a public path.
1221 outer_type_is_public_path: bool,
1224 impl<'a, 'tcx> ObsoleteVisiblePrivateTypesVisitor<'a, 'tcx> {
1225 fn path_is_private_type(&self, path: &hir::Path) -> bool {
1226 let did = match path.res {
1227 Res::PrimTy(..) | Res::SelfTy(..) | Res::Err => return false,
1228 res => res.def_id(),
1231 // A path can only be private if:
1232 // it's in this crate...
1233 if let Some(hir_id) = self.tcx.hir().as_local_hir_id(did) {
1234 // .. and it corresponds to a private type in the AST (this returns
1235 // `None` for type parameters).
1236 match self.tcx.hir().find(hir_id) {
1237 Some(Node::Item(ref item)) => !item.vis.node.is_pub(),
1238 Some(_) | None => false,
1245 fn trait_is_public(&self, trait_id: hir::HirId) -> bool {
1246 // FIXME: this would preferably be using `exported_items`, but all
1247 // traits are exported currently (see `EmbargoVisitor.exported_trait`).
1248 self.access_levels.is_public(trait_id)
1251 fn check_generic_bound(&mut self, bound: &hir::GenericBound) {
1252 if let hir::GenericBound::Trait(ref trait_ref, _) = *bound {
1253 if self.path_is_private_type(&trait_ref.trait_ref.path) {
1254 self.old_error_set.insert(trait_ref.trait_ref.hir_ref_id);
1259 fn item_is_public(&self, id: &hir::HirId, vis: &hir::Visibility) -> bool {
1260 self.access_levels.is_reachable(*id) || vis.node.is_pub()
1264 impl<'a, 'b, 'tcx, 'v> Visitor<'v> for ObsoleteCheckTypeForPrivatenessVisitor<'a, 'b, 'tcx> {
1265 fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'v> {
1266 NestedVisitorMap::None
1269 fn visit_ty(&mut self, ty: &hir::Ty) {
1270 if let hir::TyKind::Path(hir::QPath::Resolved(_, ref path)) = ty.node {
1271 if self.inner.path_is_private_type(path) {
1272 self.contains_private = true;
1273 // Found what we're looking for, so let's stop working.
1277 if let hir::TyKind::Path(_) = ty.node {
1278 if self.at_outer_type {
1279 self.outer_type_is_public_path = true;
1282 self.at_outer_type = false;
1283 intravisit::walk_ty(self, ty)
1286 // Don't want to recurse into `[, .. expr]`.
1287 fn visit_expr(&mut self, _: &hir::Expr) {}
1290 impl<'a, 'tcx> Visitor<'tcx> for ObsoleteVisiblePrivateTypesVisitor<'a, 'tcx> {
1291 /// We want to visit items in the context of their containing
1292 /// module and so forth, so supply a crate for doing a deep walk.
1293 fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> {
1294 NestedVisitorMap::All(&self.tcx.hir())
1297 fn visit_item(&mut self, item: &'tcx hir::Item) {
1299 // Contents of a private mod can be re-exported, so we need
1300 // to check internals.
1301 hir::ItemKind::Mod(_) => {}
1303 // An `extern {}` doesn't introduce a new privacy
1304 // namespace (the contents have their own privacies).
1305 hir::ItemKind::ForeignMod(_) => {}
1307 hir::ItemKind::Trait(.., ref bounds, _) => {
1308 if !self.trait_is_public(item.hir_id) {
1312 for bound in bounds.iter() {
1313 self.check_generic_bound(bound)
1317 // Impls need some special handling to try to offer useful
1318 // error messages without (too many) false positives
1319 // (i.e., we could just return here to not check them at
1320 // all, or some worse estimation of whether an impl is
1321 // publicly visible).
1322 hir::ItemKind::Impl(.., ref g, ref trait_ref, ref self_, ref impl_item_refs) => {
1323 // `impl [... for] Private` is never visible.
1324 let self_contains_private;
1325 // `impl [... for] Public<...>`, but not `impl [... for]
1326 // Vec<Public>` or `(Public,)`, etc.
1327 let self_is_public_path;
1329 // Check the properties of the `Self` type:
1331 let mut visitor = ObsoleteCheckTypeForPrivatenessVisitor {
1333 contains_private: false,
1334 at_outer_type: true,
1335 outer_type_is_public_path: false,
1337 visitor.visit_ty(&self_);
1338 self_contains_private = visitor.contains_private;
1339 self_is_public_path = visitor.outer_type_is_public_path;
1342 // Miscellaneous info about the impl:
1344 // `true` iff this is `impl Private for ...`.
1345 let not_private_trait =
1346 trait_ref.as_ref().map_or(true, // no trait counts as public trait
1348 let did = tr.path.res.def_id();
1350 if let Some(hir_id) = self.tcx.hir().as_local_hir_id(did) {
1351 self.trait_is_public(hir_id)
1353 true // external traits must be public
1357 // `true` iff this is a trait impl or at least one method is public.
1359 // `impl Public { $( fn ...() {} )* }` is not visible.
1361 // This is required over just using the methods' privacy
1362 // directly because we might have `impl<T: Foo<Private>> ...`,
1363 // and we shouldn't warn about the generics if all the methods
1364 // are private (because `T` won't be visible externally).
1365 let trait_or_some_public_method =
1366 trait_ref.is_some() ||
1367 impl_item_refs.iter()
1368 .any(|impl_item_ref| {
1369 let impl_item = self.tcx.hir().impl_item(impl_item_ref.id);
1370 match impl_item.node {
1371 hir::ImplItemKind::Const(..) |
1372 hir::ImplItemKind::Method(..) => {
1373 self.access_levels.is_reachable(
1374 impl_item_ref.id.hir_id)
1376 hir::ImplItemKind::Existential(..) |
1377 hir::ImplItemKind::Type(_) => false,
1381 if !self_contains_private &&
1382 not_private_trait &&
1383 trait_or_some_public_method {
1385 intravisit::walk_generics(self, g);
1389 for impl_item_ref in impl_item_refs {
1390 // This is where we choose whether to walk down
1391 // further into the impl to check its items. We
1392 // should only walk into public items so that we
1393 // don't erroneously report errors for private
1394 // types in private items.
1395 let impl_item = self.tcx.hir().impl_item(impl_item_ref.id);
1396 match impl_item.node {
1397 hir::ImplItemKind::Const(..) |
1398 hir::ImplItemKind::Method(..)
1399 if self.item_is_public(&impl_item.hir_id, &impl_item.vis) =>
1401 intravisit::walk_impl_item(self, impl_item)
1403 hir::ImplItemKind::Type(..) => {
1404 intravisit::walk_impl_item(self, impl_item)
1411 // Any private types in a trait impl fall into three
1413 // 1. mentioned in the trait definition
1414 // 2. mentioned in the type params/generics
1415 // 3. mentioned in the associated types of the impl
1417 // Those in 1. can only occur if the trait is in
1418 // this crate and will've been warned about on the
1419 // trait definition (there's no need to warn twice
1420 // so we don't check the methods).
1422 // Those in 2. are warned via walk_generics and this
1424 intravisit::walk_path(self, &tr.path);
1426 // Those in 3. are warned with this call.
1427 for impl_item_ref in impl_item_refs {
1428 let impl_item = self.tcx.hir().impl_item(impl_item_ref.id);
1429 if let hir::ImplItemKind::Type(ref ty) = impl_item.node {
1435 } else if trait_ref.is_none() && self_is_public_path {
1436 // `impl Public<Private> { ... }`. Any public static
1437 // methods will be visible as `Public::foo`.
1438 let mut found_pub_static = false;
1439 for impl_item_ref in impl_item_refs {
1440 if self.item_is_public(&impl_item_ref.id.hir_id, &impl_item_ref.vis) {
1441 let impl_item = self.tcx.hir().impl_item(impl_item_ref.id);
1442 match impl_item_ref.kind {
1443 AssocItemKind::Const => {
1444 found_pub_static = true;
1445 intravisit::walk_impl_item(self, impl_item);
1447 AssocItemKind::Method { has_self: false } => {
1448 found_pub_static = true;
1449 intravisit::walk_impl_item(self, impl_item);
1455 if found_pub_static {
1456 intravisit::walk_generics(self, g)
1462 // `type ... = ...;` can contain private types, because
1463 // we're introducing a new name.
1464 hir::ItemKind::Ty(..) => return,
1466 // Not at all public, so we don't care.
1467 _ if !self.item_is_public(&item.hir_id, &item.vis) => {
1474 // We've carefully constructed it so that if we're here, then
1475 // any `visit_ty`'s will be called on things that are in
1476 // public signatures, i.e., things that we're interested in for
1478 intravisit::walk_item(self, item);
1481 fn visit_generics(&mut self, generics: &'tcx hir::Generics) {
1482 for param in &generics.params {
1483 for bound in ¶m.bounds {
1484 self.check_generic_bound(bound);
1487 for predicate in &generics.where_clause.predicates {
1489 hir::WherePredicate::BoundPredicate(bound_pred) => {
1490 for bound in bound_pred.bounds.iter() {
1491 self.check_generic_bound(bound)
1494 hir::WherePredicate::RegionPredicate(_) => {}
1495 hir::WherePredicate::EqPredicate(eq_pred) => {
1496 self.visit_ty(&eq_pred.rhs_ty);
1502 fn visit_foreign_item(&mut self, item: &'tcx hir::ForeignItem) {
1503 if self.access_levels.is_reachable(item.hir_id) {
1504 intravisit::walk_foreign_item(self, item)
1508 fn visit_ty(&mut self, t: &'tcx hir::Ty) {
1509 if let hir::TyKind::Path(hir::QPath::Resolved(_, ref path)) = t.node {
1510 if self.path_is_private_type(path) {
1511 self.old_error_set.insert(t.hir_id);
1514 intravisit::walk_ty(self, t)
1517 fn visit_variant(&mut self,
1518 v: &'tcx hir::Variant,
1519 g: &'tcx hir::Generics,
1520 item_id: hir::HirId) {
1521 if self.access_levels.is_reachable(v.node.id) {
1522 self.in_variant = true;
1523 intravisit::walk_variant(self, v, g, item_id);
1524 self.in_variant = false;
1528 fn visit_struct_field(&mut self, s: &'tcx hir::StructField) {
1529 if s.vis.node.is_pub() || self.in_variant {
1530 intravisit::walk_struct_field(self, s);
1534 // We don't need to introspect into these at all: an
1535 // expression/block context can't possibly contain exported things.
1536 // (Making them no-ops stops us from traversing the whole AST without
1537 // having to be super careful about our `walk_...` calls above.)
1538 fn visit_block(&mut self, _: &'tcx hir::Block) {}
1539 fn visit_expr(&mut self, _: &'tcx hir::Expr) {}
1542 ///////////////////////////////////////////////////////////////////////////////
1543 /// SearchInterfaceForPrivateItemsVisitor traverses an item's interface and
1544 /// finds any private components in it.
1545 /// PrivateItemsInPublicInterfacesVisitor ensures there are no private types
1546 /// and traits in public interfaces.
1547 ///////////////////////////////////////////////////////////////////////////////
1549 struct SearchInterfaceForPrivateItemsVisitor<'tcx> {
1551 item_id: hir::HirId,
1554 /// The visitor checks that each component type is at least this visible.
1555 required_visibility: ty::Visibility,
1556 has_pub_restricted: bool,
1557 has_old_errors: bool,
1561 impl SearchInterfaceForPrivateItemsVisitor<'tcx> {
1562 fn generics(&mut self) -> &mut Self {
1563 for param in &self.tcx.generics_of(self.item_def_id).params {
1565 GenericParamDefKind::Lifetime => {}
1566 GenericParamDefKind::Type { has_default, .. } => {
1568 self.visit(self.tcx.type_of(param.def_id));
1571 GenericParamDefKind::Const => {
1572 self.visit(self.tcx.type_of(param.def_id));
1579 fn predicates(&mut self) -> &mut Self {
1580 // N.B., we use `explicit_predicates_of` and not `predicates_of`
1581 // because we don't want to report privacy errors due to where
1582 // clauses that the compiler inferred. We only want to
1583 // consider the ones that the user wrote. This is important
1584 // for the inferred outlives rules; see
1585 // `src/test/ui/rfc-2093-infer-outlives/privacy.rs`.
1586 self.visit_predicates(self.tcx.explicit_predicates_of(self.item_def_id));
1590 fn ty(&mut self) -> &mut Self {
1591 self.visit(self.tcx.type_of(self.item_def_id));
1595 fn check_def_id(&mut self, def_id: DefId, kind: &str, descr: &dyn fmt::Display) -> bool {
1596 if self.leaks_private_dep(def_id) {
1597 self.tcx.lint_hir(lint::builtin::EXPORTED_PRIVATE_DEPENDENCIES,
1600 &format!("{} `{}` from private dependency '{}' in public \
1601 interface", kind, descr,
1602 self.tcx.crate_name(def_id.krate)));
1606 let hir_id = match self.tcx.hir().as_local_hir_id(def_id) {
1607 Some(hir_id) => hir_id,
1608 None => return false,
1611 let (vis, vis_span, vis_descr) = def_id_visibility(self.tcx, def_id);
1612 if !vis.is_at_least(self.required_visibility, self.tcx) {
1613 let msg = format!("{} {} `{}` in public interface", vis_descr, kind, descr);
1614 if self.has_pub_restricted || self.has_old_errors || self.in_assoc_ty {
1615 let mut err = if kind == "trait" {
1616 struct_span_err!(self.tcx.sess, self.span, E0445, "{}", msg)
1618 struct_span_err!(self.tcx.sess, self.span, E0446, "{}", msg)
1620 err.span_label(self.span, format!("can't leak {} {}", vis_descr, kind));
1621 err.span_label(vis_span, format!("`{}` declared as {}", descr, vis_descr));
1624 let err_code = if kind == "trait" { "E0445" } else { "E0446" };
1625 self.tcx.lint_hir(lint::builtin::PRIVATE_IN_PUBLIC, hir_id, self.span,
1626 &format!("{} (error {})", msg, err_code));
1634 /// An item is 'leaked' from a private dependency if all
1635 /// of the following are true:
1636 /// 1. It's contained within a public type
1637 /// 2. It comes from a private crate
1638 fn leaks_private_dep(&self, item_id: DefId) -> bool {
1639 let ret = self.required_visibility == ty::Visibility::Public &&
1640 self.tcx.is_private_dep(item_id.krate);
1642 log::debug!("leaks_private_dep(item_id={:?})={}", item_id, ret);
1647 impl DefIdVisitor<'tcx> for SearchInterfaceForPrivateItemsVisitor<'tcx> {
1648 fn tcx(&self) -> TyCtxt<'tcx> { self.tcx }
1649 fn visit_def_id(&mut self, def_id: DefId, kind: &str, descr: &dyn fmt::Display) -> bool {
1650 self.check_def_id(def_id, kind, descr)
1654 struct PrivateItemsInPublicInterfacesVisitor<'a, 'tcx> {
1656 has_pub_restricted: bool,
1657 old_error_set: &'a HirIdSet,
1660 impl<'a, 'tcx> PrivateItemsInPublicInterfacesVisitor<'a, 'tcx> {
1663 item_id: hir::HirId,
1664 required_visibility: ty::Visibility,
1665 ) -> SearchInterfaceForPrivateItemsVisitor<'tcx> {
1666 let mut has_old_errors = false;
1668 // Slow path taken only if there any errors in the crate.
1669 for &id in self.old_error_set {
1670 // Walk up the nodes until we find `item_id` (or we hit a root).
1674 has_old_errors = true;
1677 let parent = self.tcx.hir().get_parent_node(id);
1689 SearchInterfaceForPrivateItemsVisitor {
1692 item_def_id: self.tcx.hir().local_def_id_from_hir_id(item_id),
1693 span: self.tcx.hir().span(item_id),
1694 required_visibility,
1695 has_pub_restricted: self.has_pub_restricted,
1701 fn check_assoc_item(
1704 assoc_item_kind: AssocItemKind,
1705 defaultness: hir::Defaultness,
1706 vis: ty::Visibility,
1708 let mut check = self.check(hir_id, vis);
1710 let (check_ty, is_assoc_ty) = match assoc_item_kind {
1711 AssocItemKind::Const | AssocItemKind::Method { .. } => (true, false),
1712 AssocItemKind::Type => (defaultness.has_value(), true),
1713 // `ty()` for existential types is the underlying type,
1714 // it's not a part of interface, so we skip it.
1715 AssocItemKind::Existential => (false, true),
1717 check.in_assoc_ty = is_assoc_ty;
1718 check.generics().predicates();
1725 impl<'a, 'tcx> Visitor<'tcx> for PrivateItemsInPublicInterfacesVisitor<'a, 'tcx> {
1726 fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> {
1727 NestedVisitorMap::OnlyBodies(&self.tcx.hir())
1730 fn visit_item(&mut self, item: &'tcx hir::Item) {
1732 let item_visibility = ty::Visibility::from_hir(&item.vis, item.hir_id, tcx);
1735 // Crates are always public.
1736 hir::ItemKind::ExternCrate(..) => {}
1737 // All nested items are checked by `visit_item`.
1738 hir::ItemKind::Mod(..) => {}
1739 // Checked in resolve.
1740 hir::ItemKind::Use(..) => {}
1742 hir::ItemKind::GlobalAsm(..) => {}
1743 // Subitems of these items have inherited publicity.
1744 hir::ItemKind::Const(..) | hir::ItemKind::Static(..) |
1745 hir::ItemKind::Fn(..) | hir::ItemKind::Ty(..) => {
1746 self.check(item.hir_id, item_visibility).generics().predicates().ty();
1748 hir::ItemKind::Existential(..) => {
1749 // `ty()` for existential types is the underlying type,
1750 // it's not a part of interface, so we skip it.
1751 self.check(item.hir_id, item_visibility).generics().predicates();
1753 hir::ItemKind::Trait(.., ref trait_item_refs) => {
1754 self.check(item.hir_id, item_visibility).generics().predicates();
1756 for trait_item_ref in trait_item_refs {
1757 self.check_assoc_item(
1758 trait_item_ref.id.hir_id,
1759 trait_item_ref.kind,
1760 trait_item_ref.defaultness,
1765 hir::ItemKind::TraitAlias(..) => {
1766 self.check(item.hir_id, item_visibility).generics().predicates();
1768 hir::ItemKind::Enum(ref def, _) => {
1769 self.check(item.hir_id, item_visibility).generics().predicates();
1771 for variant in &def.variants {
1772 for field in variant.node.data.fields() {
1773 self.check(field.hir_id, item_visibility).ty();
1777 // Subitems of foreign modules have their own publicity.
1778 hir::ItemKind::ForeignMod(ref foreign_mod) => {
1779 for foreign_item in &foreign_mod.items {
1780 let vis = ty::Visibility::from_hir(&foreign_item.vis, item.hir_id, tcx);
1781 self.check(foreign_item.hir_id, vis).generics().predicates().ty();
1784 // Subitems of structs and unions have their own publicity.
1785 hir::ItemKind::Struct(ref struct_def, _) |
1786 hir::ItemKind::Union(ref struct_def, _) => {
1787 self.check(item.hir_id, item_visibility).generics().predicates();
1789 for field in struct_def.fields() {
1790 let field_visibility = ty::Visibility::from_hir(&field.vis, item.hir_id, tcx);
1791 self.check(field.hir_id, min(item_visibility, field_visibility, tcx)).ty();
1794 // An inherent impl is public when its type is public
1795 // Subitems of inherent impls have their own publicity.
1796 // A trait impl is public when both its type and its trait are public
1797 // Subitems of trait impls have inherited publicity.
1798 hir::ItemKind::Impl(.., ref trait_ref, _, ref impl_item_refs) => {
1799 let impl_vis = ty::Visibility::of_impl(item.hir_id, tcx, &Default::default());
1800 self.check(item.hir_id, impl_vis).generics().predicates();
1801 for impl_item_ref in impl_item_refs {
1802 let impl_item = tcx.hir().impl_item(impl_item_ref.id);
1803 let impl_item_vis = if trait_ref.is_none() {
1804 min(ty::Visibility::from_hir(&impl_item.vis, item.hir_id, tcx),
1810 self.check_assoc_item(
1811 impl_item_ref.id.hir_id,
1813 impl_item_ref.defaultness,
1822 pub fn provide(providers: &mut Providers<'_>) {
1823 *providers = Providers {
1824 privacy_access_levels,
1825 check_private_in_public,
1831 fn check_mod_privacy<'tcx>(tcx: TyCtxt<'tcx>, module_def_id: DefId) {
1832 let empty_tables = ty::TypeckTables::empty(None);
1834 // Check privacy of names not checked in previous compilation stages.
1835 let mut visitor = NamePrivacyVisitor {
1837 tables: &empty_tables,
1838 current_item: hir::DUMMY_HIR_ID,
1839 empty_tables: &empty_tables,
1841 let (module, span, hir_id) = tcx.hir().get_module(module_def_id);
1843 intravisit::walk_mod(&mut visitor, module, hir_id);
1845 // Check privacy of explicitly written types and traits as well as
1846 // inferred types of expressions and patterns.
1847 let mut visitor = TypePrivacyVisitor {
1849 tables: &empty_tables,
1850 current_item: module_def_id,
1853 empty_tables: &empty_tables,
1855 intravisit::walk_mod(&mut visitor, module, hir_id);
1858 fn privacy_access_levels<'tcx>(tcx: TyCtxt<'tcx>, krate: CrateNum) -> &'tcx AccessLevels {
1859 assert_eq!(krate, LOCAL_CRATE);
1861 // Build up a set of all exported items in the AST. This is a set of all
1862 // items which are reachable from external crates based on visibility.
1863 let mut visitor = EmbargoVisitor {
1865 access_levels: Default::default(),
1866 prev_level: Some(AccessLevel::Public),
1870 intravisit::walk_crate(&mut visitor, tcx.hir().krate());
1871 if visitor.changed {
1872 visitor.changed = false;
1877 visitor.update(hir::CRATE_HIR_ID, Some(AccessLevel::Public));
1879 tcx.arena.alloc(visitor.access_levels)
1882 fn check_private_in_public<'tcx>(tcx: TyCtxt<'tcx>, krate: CrateNum) {
1883 assert_eq!(krate, LOCAL_CRATE);
1885 let access_levels = tcx.privacy_access_levels(LOCAL_CRATE);
1887 let krate = tcx.hir().krate();
1889 let mut visitor = ObsoleteVisiblePrivateTypesVisitor {
1891 access_levels: &access_levels,
1893 old_error_set: Default::default(),
1895 intravisit::walk_crate(&mut visitor, krate);
1897 let has_pub_restricted = {
1898 let mut pub_restricted_visitor = PubRestrictedVisitor {
1900 has_pub_restricted: false
1902 intravisit::walk_crate(&mut pub_restricted_visitor, krate);
1903 pub_restricted_visitor.has_pub_restricted
1906 // Check for private types and traits in public interfaces.
1907 let mut visitor = PrivateItemsInPublicInterfacesVisitor {
1910 old_error_set: &visitor.old_error_set,
1912 krate.visit_all_item_likes(&mut DeepVisitor::new(&mut visitor));
1915 __build_diagnostic_array! { librustc_privacy, DIAGNOSTICS }