1 #![doc(html_root_url = "https://doc.rust-lang.org/nightly/")]
3 #![feature(in_band_lifetimes)]
5 #![feature(rustc_diagnostic_macros)]
7 #![recursion_limit="256"]
9 #[macro_use] extern crate syntax;
12 use rustc::hir::{self, Node, PatKind, AssocItemKind};
13 use rustc::hir::def::{Res, DefKind};
14 use rustc::hir::def_id::{CRATE_DEF_INDEX, LOCAL_CRATE, CrateNum, DefId};
15 use rustc::hir::intravisit::{self, Visitor, NestedVisitorMap};
16 use rustc::hir::itemlikevisit::DeepVisitor;
18 use rustc::middle::privacy::{AccessLevel, AccessLevels};
19 use rustc::ty::{self, TyCtxt, Ty, TraitRef, TypeFoldable, GenericParamDefKind};
20 use rustc::ty::fold::TypeVisitor;
21 use rustc::ty::query::Providers;
22 use rustc::ty::subst::InternalSubsts;
23 use rustc::util::nodemap::HirIdSet;
24 use rustc_data_structures::fx::FxHashSet;
25 use syntax::ast::Ident;
27 use syntax::symbol::{kw, sym};
28 use syntax_pos::hygiene::Transparency;
31 use std::{cmp, fmt, mem};
32 use std::marker::PhantomData;
36 ////////////////////////////////////////////////////////////////////////////////
37 /// Generic infrastructure used to implement specific visitors below.
38 ////////////////////////////////////////////////////////////////////////////////
40 /// Implemented to visit all `DefId`s in a type.
41 /// Visiting `DefId`s is useful because visibilities and reachabilities are attached to them.
42 /// The idea is to visit "all components of a type", as documented in
43 /// https://github.com/rust-lang/rfcs/blob/master/text/2145-type-privacy.md#how-to-determine-visibility-of-a-type.
44 /// The default type visitor (`TypeVisitor`) does most of the job, but it has some shortcomings.
45 /// First, it doesn't have overridable `fn visit_trait_ref`, so we have to catch trait `DefId`s
46 /// manually. Second, it doesn't visit some type components like signatures of fn types, or traits
47 /// in `impl Trait`, see individual comments in `DefIdVisitorSkeleton::visit_ty`.
48 trait DefIdVisitor<'tcx> {
49 fn tcx(&self) -> TyCtxt<'tcx>;
50 fn shallow(&self) -> bool { false }
51 fn skip_assoc_tys(&self) -> bool { false }
52 fn visit_def_id(&mut self, def_id: DefId, kind: &str, descr: &dyn fmt::Display) -> bool;
54 /// Not overridden, but used to actually visit types and traits.
55 fn skeleton(&mut self) -> DefIdVisitorSkeleton<'_, 'tcx, Self> {
56 DefIdVisitorSkeleton {
58 visited_opaque_tys: Default::default(),
59 dummy: Default::default(),
62 fn visit(&mut self, ty_fragment: impl TypeFoldable<'tcx>) -> bool {
63 ty_fragment.visit_with(&mut self.skeleton())
65 fn visit_trait(&mut self, trait_ref: TraitRef<'tcx>) -> bool {
66 self.skeleton().visit_trait(trait_ref)
68 fn visit_predicates(&mut self, predicates: &ty::GenericPredicates<'tcx>) -> bool {
69 self.skeleton().visit_predicates(predicates)
73 struct DefIdVisitorSkeleton<'v, 'tcx, V>
75 V: DefIdVisitor<'tcx> + ?Sized,
77 def_id_visitor: &'v mut V,
78 visited_opaque_tys: FxHashSet<DefId>,
79 dummy: PhantomData<TyCtxt<'tcx>>,
82 impl<'tcx, V> DefIdVisitorSkeleton<'_, 'tcx, V>
84 V: DefIdVisitor<'tcx> + ?Sized,
86 fn visit_trait(&mut self, trait_ref: TraitRef<'tcx>) -> bool {
87 let TraitRef { def_id, substs } = trait_ref;
88 self.def_id_visitor.visit_def_id(def_id, "trait", &trait_ref) ||
89 (!self.def_id_visitor.shallow() && substs.visit_with(self))
92 fn visit_predicates(&mut self, predicates: &ty::GenericPredicates<'tcx>) -> bool {
93 let ty::GenericPredicates { parent: _, predicates } = predicates;
94 for (predicate, _span) in predicates {
96 ty::Predicate::Trait(poly_predicate) => {
97 let ty::TraitPredicate { trait_ref } = *poly_predicate.skip_binder();
98 if self.visit_trait(trait_ref) {
102 ty::Predicate::Projection(poly_predicate) => {
103 let ty::ProjectionPredicate { projection_ty, ty } =
104 *poly_predicate.skip_binder();
105 if ty.visit_with(self) {
108 if self.visit_trait(projection_ty.trait_ref(self.def_id_visitor.tcx())) {
112 ty::Predicate::TypeOutlives(poly_predicate) => {
113 let ty::OutlivesPredicate(ty, _region) = *poly_predicate.skip_binder();
114 if ty.visit_with(self) {
118 ty::Predicate::RegionOutlives(..) => {},
119 _ => bug!("unexpected predicate: {:?}", predicate),
126 impl<'tcx, V> TypeVisitor<'tcx> for DefIdVisitorSkeleton<'_, 'tcx, V>
128 V: DefIdVisitor<'tcx> + ?Sized,
130 fn visit_ty(&mut self, ty: Ty<'tcx>) -> bool {
131 let tcx = self.def_id_visitor.tcx();
132 // InternalSubsts are not visited here because they are visited below in `super_visit_with`.
134 ty::Adt(&ty::AdtDef { did: def_id, .. }, ..) |
135 ty::Foreign(def_id) |
136 ty::FnDef(def_id, ..) |
137 ty::Closure(def_id, ..) |
138 ty::Generator(def_id, ..) => {
139 if self.def_id_visitor.visit_def_id(def_id, "type", &ty) {
142 if self.def_id_visitor.shallow() {
145 // Default type visitor doesn't visit signatures of fn types.
146 // Something like `fn() -> Priv {my_func}` is considered a private type even if
147 // `my_func` is public, so we need to visit signatures.
148 if let ty::FnDef(..) = ty.sty {
149 if tcx.fn_sig(def_id).visit_with(self) {
153 // Inherent static methods don't have self type in substs.
154 // Something like `fn() {my_method}` type of the method
155 // `impl Pub<Priv> { pub fn my_method() {} }` is considered a private type,
156 // so we need to visit the self type additionally.
157 if let Some(assoc_item) = tcx.opt_associated_item(def_id) {
158 if let ty::ImplContainer(impl_def_id) = assoc_item.container {
159 if tcx.type_of(impl_def_id).visit_with(self) {
165 ty::Projection(proj) | ty::UnnormalizedProjection(proj) => {
166 if self.def_id_visitor.skip_assoc_tys() {
167 // Visitors searching for minimal visibility/reachability want to
168 // conservatively approximate associated types like `<Type as Trait>::Alias`
169 // as visible/reachable even if both `Type` and `Trait` are private.
170 // Ideally, associated types should be substituted in the same way as
171 // free type aliases, but this isn't done yet.
174 // This will also visit substs if necessary, so we don't need to recurse.
175 return self.visit_trait(proj.trait_ref(tcx));
177 ty::Dynamic(predicates, ..) => {
178 // All traits in the list are considered the "primary" part of the type
179 // and are visited by shallow visitors.
180 for predicate in *predicates.skip_binder() {
181 let trait_ref = match *predicate {
182 ty::ExistentialPredicate::Trait(trait_ref) => trait_ref,
183 ty::ExistentialPredicate::Projection(proj) => proj.trait_ref(tcx),
184 ty::ExistentialPredicate::AutoTrait(def_id) =>
185 ty::ExistentialTraitRef { def_id, substs: InternalSubsts::empty() },
187 let ty::ExistentialTraitRef { def_id, substs: _ } = trait_ref;
188 if self.def_id_visitor.visit_def_id(def_id, "trait", &trait_ref) {
193 ty::Opaque(def_id, ..) => {
194 // Skip repeated `Opaque`s to avoid infinite recursion.
195 if self.visited_opaque_tys.insert(def_id) {
196 // The intent is to treat `impl Trait1 + Trait2` identically to
197 // `dyn Trait1 + Trait2`. Therefore we ignore def-id of the opaque type itself
198 // (it either has no visibility, or its visibility is insignificant, like
199 // visibilities of type aliases) and recurse into predicates instead to go
200 // through the trait list (default type visitor doesn't visit those traits).
201 // All traits in the list are considered the "primary" part of the type
202 // and are visited by shallow visitors.
203 if self.visit_predicates(tcx.predicates_of(def_id)) {
208 // These types don't have their own def-ids (but may have subcomponents
209 // with def-ids that should be visited recursively).
210 ty::Bool | ty::Char | ty::Int(..) | ty::Uint(..) |
211 ty::Float(..) | ty::Str | ty::Never |
212 ty::Array(..) | ty::Slice(..) | ty::Tuple(..) |
213 ty::RawPtr(..) | ty::Ref(..) | ty::FnPtr(..) |
214 ty::Param(..) | ty::Error | ty::GeneratorWitness(..) => {}
215 ty::Bound(..) | ty::Placeholder(..) | ty::Infer(..) =>
216 bug!("unexpected type: {:?}", ty),
219 !self.def_id_visitor.shallow() && ty.super_visit_with(self)
223 fn def_id_visibility<'tcx>(
226 ) -> (ty::Visibility, Span, &'static str) {
227 match tcx.hir().as_local_hir_id(def_id) {
229 let vis = match tcx.hir().get(hir_id) {
230 Node::Item(item) => &item.vis,
231 Node::ForeignItem(foreign_item) => &foreign_item.vis,
232 Node::MacroDef(macro_def) => {
233 if attr::contains_name(¯o_def.attrs, sym::macro_export) {
234 return (ty::Visibility::Public, macro_def.span, "public");
239 Node::TraitItem(..) | Node::Variant(..) => {
240 return def_id_visibility(tcx, tcx.hir().get_parent_did(hir_id));
242 Node::ImplItem(impl_item) => {
243 match tcx.hir().get(tcx.hir().get_parent_item(hir_id)) {
244 Node::Item(item) => match &item.node {
245 hir::ItemKind::Impl(.., None, _, _) => &impl_item.vis,
246 hir::ItemKind::Impl(.., Some(trait_ref), _, _)
247 => return def_id_visibility(tcx, trait_ref.path.res.def_id()),
248 kind => bug!("unexpected item kind: {:?}", kind),
250 node => bug!("unexpected node kind: {:?}", node),
253 Node::Ctor(vdata) => {
254 let parent_hir_id = tcx.hir().get_parent_node(hir_id);
255 match tcx.hir().get(parent_hir_id) {
256 Node::Variant(..) => {
257 let parent_did = tcx.hir().local_def_id(parent_hir_id);
258 let (mut ctor_vis, mut span, mut descr) = def_id_visibility(
262 let adt_def = tcx.adt_def(tcx.hir().get_parent_did(hir_id));
263 let ctor_did = tcx.hir().local_def_id(
264 vdata.ctor_hir_id().unwrap());
265 let variant = adt_def.variant_with_ctor_id(ctor_did);
267 if variant.is_field_list_non_exhaustive() &&
268 ctor_vis == ty::Visibility::Public
270 ctor_vis = ty::Visibility::Restricted(
271 DefId::local(CRATE_DEF_INDEX));
272 let attrs = tcx.get_attrs(variant.def_id);
273 span = attr::find_by_name(&attrs, sym::non_exhaustive)
275 descr = "crate-visible";
278 return (ctor_vis, span, descr);
281 let item = match tcx.hir().get(parent_hir_id) {
282 Node::Item(item) => item,
283 node => bug!("unexpected node kind: {:?}", node),
285 let (mut ctor_vis, mut span, mut descr) =
286 (ty::Visibility::from_hir(&item.vis, parent_hir_id, tcx),
287 item.vis.span, item.vis.node.descr());
288 for field in vdata.fields() {
289 let field_vis = ty::Visibility::from_hir(&field.vis, hir_id, tcx);
290 if ctor_vis.is_at_least(field_vis, tcx) {
291 ctor_vis = field_vis;
292 span = field.vis.span;
293 descr = field.vis.node.descr();
297 // If the structure is marked as non_exhaustive then lower the
298 // visibility to within the crate.
299 if ctor_vis == ty::Visibility::Public {
301 tcx.adt_def(tcx.hir().get_parent_did(hir_id));
302 if adt_def.non_enum_variant().is_field_list_non_exhaustive() {
304 ty::Visibility::Restricted(DefId::local(CRATE_DEF_INDEX));
305 span = attr::find_by_name(&item.attrs, sym::non_exhaustive)
307 descr = "crate-visible";
311 return (ctor_vis, span, descr);
313 node => bug!("unexpected node kind: {:?}", node),
316 Node::Expr(expr) => {
317 return (ty::Visibility::Restricted(
318 tcx.hir().get_module_parent(expr.hir_id)),
319 expr.span, "private")
321 node => bug!("unexpected node kind: {:?}", node)
323 (ty::Visibility::from_hir(vis, hir_id, tcx), vis.span, vis.node.descr())
326 let vis = tcx.visibility(def_id);
327 let descr = if vis == ty::Visibility::Public { "public" } else { "private" };
328 (vis, tcx.def_span(def_id), descr)
333 // Set the correct `TypeckTables` for the given `item_id` (or an empty table if
334 // there is no `TypeckTables` for the item).
335 fn item_tables<'a, 'tcx>(
338 empty_tables: &'a ty::TypeckTables<'tcx>,
339 ) -> &'a ty::TypeckTables<'tcx> {
340 let def_id = tcx.hir().local_def_id(hir_id);
341 if tcx.has_typeck_tables(def_id) { tcx.typeck_tables_of(def_id) } else { empty_tables }
344 fn min(vis1: ty::Visibility, vis2: ty::Visibility, tcx: TyCtxt<'_>) -> ty::Visibility {
345 if vis1.is_at_least(vis2, tcx) { vis2 } else { vis1 }
348 ////////////////////////////////////////////////////////////////////////////////
349 /// Visitor used to determine if pub(restricted) is used anywhere in the crate.
351 /// This is done so that `private_in_public` warnings can be turned into hard errors
352 /// in crates that have been updated to use pub(restricted).
353 ////////////////////////////////////////////////////////////////////////////////
354 struct PubRestrictedVisitor<'tcx> {
356 has_pub_restricted: bool,
359 impl Visitor<'tcx> for PubRestrictedVisitor<'tcx> {
360 fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> {
361 NestedVisitorMap::All(&self.tcx.hir())
363 fn visit_vis(&mut self, vis: &'tcx hir::Visibility) {
364 self.has_pub_restricted = self.has_pub_restricted || vis.node.is_pub_restricted();
368 ////////////////////////////////////////////////////////////////////////////////
369 /// Visitor used to determine impl visibility and reachability.
370 ////////////////////////////////////////////////////////////////////////////////
372 struct FindMin<'a, 'tcx, VL: VisibilityLike> {
374 access_levels: &'a AccessLevels,
378 impl<'a, 'tcx, VL: VisibilityLike> DefIdVisitor<'tcx> for FindMin<'a, 'tcx, VL> {
379 fn tcx(&self) -> TyCtxt<'tcx> { self.tcx }
380 fn shallow(&self) -> bool { VL::SHALLOW }
381 fn skip_assoc_tys(&self) -> bool { true }
382 fn visit_def_id(&mut self, def_id: DefId, _kind: &str, _descr: &dyn fmt::Display) -> bool {
383 self.min = VL::new_min(self, def_id);
388 trait VisibilityLike: Sized {
390 const SHALLOW: bool = false;
391 fn new_min(find: &FindMin<'_, '_, Self>, def_id: DefId) -> Self;
393 // Returns an over-approximation (`skip_assoc_tys` = true) of visibility due to
394 // associated types for which we can't determine visibility precisely.
398 access_levels: &AccessLevels,
400 let mut find = FindMin { tcx, access_levels, min: Self::MAX };
401 let def_id = tcx.hir().local_def_id(hir_id);
402 find.visit(tcx.type_of(def_id));
403 if let Some(trait_ref) = tcx.impl_trait_ref(def_id) {
404 find.visit_trait(trait_ref);
409 impl VisibilityLike for ty::Visibility {
410 const MAX: Self = ty::Visibility::Public;
411 fn new_min(find: &FindMin<'_, '_, Self>, def_id: DefId) -> Self {
412 min(def_id_visibility(find.tcx, def_id).0, find.min, find.tcx)
415 impl VisibilityLike for Option<AccessLevel> {
416 const MAX: Self = Some(AccessLevel::Public);
417 // Type inference is very smart sometimes.
418 // It can make an impl reachable even some components of its type or trait are unreachable.
419 // E.g. methods of `impl ReachableTrait<UnreachableTy> for ReachableTy<UnreachableTy> { ... }`
420 // can be usable from other crates (#57264). So we skip substs when calculating reachability
421 // and consider an impl reachable if its "shallow" type and trait are reachable.
423 // The assumption we make here is that type-inference won't let you use an impl without knowing
424 // both "shallow" version of its self type and "shallow" version of its trait if it exists
425 // (which require reaching the `DefId`s in them).
426 const SHALLOW: bool = true;
427 fn new_min(find: &FindMin<'_, '_, Self>, def_id: DefId) -> Self {
428 cmp::min(if let Some(hir_id) = find.tcx.hir().as_local_hir_id(def_id) {
429 find.access_levels.map.get(&hir_id).cloned()
436 ////////////////////////////////////////////////////////////////////////////////
437 /// The embargo visitor, used to determine the exports of the AST.
438 ////////////////////////////////////////////////////////////////////////////////
440 struct EmbargoVisitor<'tcx> {
443 /// Accessibility levels for reachable nodes.
444 access_levels: AccessLevels,
445 /// A set of pairs corresponding to modules, where the first module is
446 /// reachable via a macro that's defined in the second module. This cannot
447 /// be represented as reachable because it can't handle the following case:
449 /// pub mod n { // Should be `Public`
450 /// pub(crate) mod p { // Should *not* be accessible
451 /// pub fn f() -> i32 { 12 } // Must be `Reachable`
457 macro_reachable: FxHashSet<(hir::HirId, DefId)>,
458 /// Previous accessibility level; `None` means unreachable.
459 prev_level: Option<AccessLevel>,
460 /// Has something changed in the level map?
464 struct ReachEverythingInTheInterfaceVisitor<'a, 'tcx> {
465 access_level: Option<AccessLevel>,
467 ev: &'a mut EmbargoVisitor<'tcx>,
470 impl EmbargoVisitor<'tcx> {
471 fn get(&self, id: hir::HirId) -> Option<AccessLevel> {
472 self.access_levels.map.get(&id).cloned()
475 /// Updates node level and returns the updated level.
476 fn update(&mut self, id: hir::HirId, level: Option<AccessLevel>) -> Option<AccessLevel> {
477 let old_level = self.get(id);
478 // Accessibility levels can only grow.
479 if level > old_level {
480 self.access_levels.map.insert(id, level.unwrap());
491 access_level: Option<AccessLevel>,
492 ) -> ReachEverythingInTheInterfaceVisitor<'_, 'tcx> {
493 ReachEverythingInTheInterfaceVisitor {
494 access_level: cmp::min(access_level, Some(AccessLevel::Reachable)),
495 item_def_id: self.tcx.hir().local_def_id(item_id),
500 /// Updates the item as being reachable through a macro defined in the given
501 /// module. Returns `true` if the level has changed.
502 fn update_macro_reachable(&mut self, reachable_mod: hir::HirId, defining_mod: DefId) -> bool {
503 if self.macro_reachable.insert((reachable_mod, defining_mod)) {
504 self.update_macro_reachable_mod(reachable_mod, defining_mod);
511 fn update_macro_reachable_mod(
513 reachable_mod: hir::HirId,
516 let module_def_id = self.tcx.hir().local_def_id(reachable_mod);
517 let module = self.tcx.hir().get_module(module_def_id).0;
518 for item_id in &module.item_ids {
519 let hir_id = item_id.id;
520 let item_def_id = self.tcx.hir().local_def_id(hir_id);
521 if let Some(def_kind) = self.tcx.def_kind(item_def_id) {
522 let item = self.tcx.hir().expect_item(hir_id);
523 let vis = ty::Visibility::from_hir(&item.vis, hir_id, self.tcx);
524 self.update_macro_reachable_def(hir_id, def_kind, vis, defining_mod);
528 if let Some(exports) = self.tcx.module_exports(module_def_id) {
529 for export in exports {
530 if export.vis.is_accessible_from(defining_mod, self.tcx) {
531 if let Res::Def(def_kind, def_id) = export.res {
532 let vis = def_id_visibility(self.tcx, def_id).0;
533 if let Some(hir_id) = self.tcx.hir().as_local_hir_id(def_id) {
534 self.update_macro_reachable_def(
547 fn update_macro_reachable_def(
554 let level = Some(AccessLevel::Reachable);
555 if let ty::Visibility::Public = vis {
556 self.update(hir_id, level);
559 // No type privacy, so can be directly marked as reachable.
563 | DefKind::TraitAlias
564 | DefKind::TyAlias => {
565 if vis.is_accessible_from(module, self.tcx) {
566 self.update(hir_id, level);
570 // We can't use a module name as the final segment of a path, except
571 // in use statements. Since re-export checking doesn't consider
572 // hygiene these don't need to be marked reachable. The contents of
573 // the module, however may be reachable.
575 if vis.is_accessible_from(module, self.tcx) {
576 self.update_macro_reachable(hir_id, module);
580 DefKind::Struct | DefKind::Union => {
581 // While structs and unions have type privacy, their fields do
583 if let ty::Visibility::Public = vis {
584 let item = self.tcx.hir().expect_item(hir_id);
585 if let hir::ItemKind::Struct(ref struct_def, _)
586 | hir::ItemKind::Union(ref struct_def, _) = item.node
588 for field in struct_def.fields() {
589 let field_vis = ty::Visibility::from_hir(
594 if field_vis.is_accessible_from(module, self.tcx) {
595 self.reach(field.hir_id, level).ty();
599 bug!("item {:?} with DefKind {:?}", item, def_kind);
604 // These have type privacy, so are not reachable unless they're
608 | DefKind::AssocOpaqueTy
609 | DefKind::ConstParam
610 | DefKind::Ctor(_, _)
618 | DefKind::Variant => (),
622 /// Given the path segments of a `ItemKind::Use`, then we need
623 /// to update the visibility of the intermediate use so that it isn't linted
624 /// by `unreachable_pub`.
626 /// This isn't trivial as `path.res` has the `DefId` of the eventual target
627 /// of the use statement not of the next intermediate use statement.
629 /// To do this, consider the last two segments of the path to our intermediate
630 /// use statement. We expect the penultimate segment to be a module and the
631 /// last segment to be the name of the item we are exporting. We can then
632 /// look at the items contained in the module for the use statement with that
633 /// name and update that item's visibility.
635 /// FIXME: This solution won't work with glob imports and doesn't respect
636 /// namespaces. See <https://github.com/rust-lang/rust/pull/57922#discussion_r251234202>.
637 fn update_visibility_of_intermediate_use_statements(&mut self, segments: &[hir::PathSegment]) {
638 if let Some([module, segment]) = segments.rchunks_exact(2).next() {
639 if let Some(item) = module.res
640 .and_then(|res| res.mod_def_id())
641 .and_then(|def_id| self.tcx.hir().as_local_hir_id(def_id))
642 .map(|module_hir_id| self.tcx.hir().expect_item(module_hir_id))
644 if let hir::ItemKind::Mod(m) = &item.node {
645 for item_id in m.item_ids.as_ref() {
646 let item = self.tcx.hir().expect_item(item_id.id);
647 let def_id = self.tcx.hir().local_def_id(item_id.id);
648 if !self.tcx.hygienic_eq(segment.ident, item.ident, def_id) { continue; }
649 if let hir::ItemKind::Use(..) = item.node {
650 self.update(item.hir_id, Some(AccessLevel::Exported));
659 impl Visitor<'tcx> for EmbargoVisitor<'tcx> {
660 /// We want to visit items in the context of their containing
661 /// module and so forth, so supply a crate for doing a deep walk.
662 fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> {
663 NestedVisitorMap::All(&self.tcx.hir())
666 fn visit_item(&mut self, item: &'tcx hir::Item) {
667 let inherited_item_level = match item.node {
668 hir::ItemKind::Impl(..) =>
669 Option::<AccessLevel>::of_impl(item.hir_id, self.tcx, &self.access_levels),
670 // Foreign modules inherit level from parents.
671 hir::ItemKind::ForeignMod(..) => self.prev_level,
672 // Other `pub` items inherit levels from parents.
673 hir::ItemKind::Const(..) | hir::ItemKind::Enum(..) | hir::ItemKind::ExternCrate(..) |
674 hir::ItemKind::GlobalAsm(..) | hir::ItemKind::Fn(..) | hir::ItemKind::Mod(..) |
675 hir::ItemKind::Static(..) | hir::ItemKind::Struct(..) |
676 hir::ItemKind::Trait(..) | hir::ItemKind::TraitAlias(..) |
677 hir::ItemKind::OpaqueTy(..) |
678 hir::ItemKind::TyAlias(..) | hir::ItemKind::Union(..) | hir::ItemKind::Use(..) => {
679 if item.vis.node.is_pub() { self.prev_level } else { None }
683 // Update level of the item itself.
684 let item_level = self.update(item.hir_id, inherited_item_level);
686 // Update levels of nested things.
688 hir::ItemKind::Enum(ref def, _) => {
689 for variant in &def.variants {
690 let variant_level = self.update(variant.node.id, item_level);
691 if let Some(ctor_hir_id) = variant.node.data.ctor_hir_id() {
692 self.update(ctor_hir_id, item_level);
694 for field in variant.node.data.fields() {
695 self.update(field.hir_id, variant_level);
699 hir::ItemKind::Impl(.., ref trait_ref, _, ref impl_item_refs) => {
700 for impl_item_ref in impl_item_refs {
701 if trait_ref.is_some() || impl_item_ref.vis.node.is_pub() {
702 self.update(impl_item_ref.id.hir_id, item_level);
706 hir::ItemKind::Trait(.., ref trait_item_refs) => {
707 for trait_item_ref in trait_item_refs {
708 self.update(trait_item_ref.id.hir_id, item_level);
711 hir::ItemKind::Struct(ref def, _) | hir::ItemKind::Union(ref def, _) => {
712 if let Some(ctor_hir_id) = def.ctor_hir_id() {
713 self.update(ctor_hir_id, item_level);
715 for field in def.fields() {
716 if field.vis.node.is_pub() {
717 self.update(field.hir_id, item_level);
721 hir::ItemKind::ForeignMod(ref foreign_mod) => {
722 for foreign_item in &foreign_mod.items {
723 if foreign_item.vis.node.is_pub() {
724 self.update(foreign_item.hir_id, item_level);
728 hir::ItemKind::OpaqueTy(..) |
729 hir::ItemKind::Use(..) |
730 hir::ItemKind::Static(..) |
731 hir::ItemKind::Const(..) |
732 hir::ItemKind::GlobalAsm(..) |
733 hir::ItemKind::TyAlias(..) |
734 hir::ItemKind::Mod(..) |
735 hir::ItemKind::TraitAlias(..) |
736 hir::ItemKind::Fn(..) |
737 hir::ItemKind::ExternCrate(..) => {}
740 // Mark all items in interfaces of reachable items as reachable.
742 // The interface is empty.
743 hir::ItemKind::ExternCrate(..) => {}
744 // All nested items are checked by `visit_item`.
745 hir::ItemKind::Mod(..) => {}
746 // Re-exports are handled in `visit_mod`. However, in order to avoid looping over
747 // all of the items of a mod in `visit_mod` looking for use statements, we handle
748 // making sure that intermediate use statements have their visibilities updated here.
749 hir::ItemKind::Use(ref path, _) => {
750 if item_level.is_some() {
751 self.update_visibility_of_intermediate_use_statements(path.segments.as_ref());
754 // The interface is empty.
755 hir::ItemKind::GlobalAsm(..) => {}
756 hir::ItemKind::OpaqueTy(..) => {
757 // FIXME: This is some serious pessimization intended to workaround deficiencies
758 // in the reachability pass (`middle/reachable.rs`). Types are marked as link-time
759 // reachable if they are returned via `impl Trait`, even from private functions.
760 let exist_level = cmp::max(item_level, Some(AccessLevel::ReachableFromImplTrait));
761 self.reach(item.hir_id, exist_level).generics().predicates().ty();
764 hir::ItemKind::Const(..) | hir::ItemKind::Static(..) |
765 hir::ItemKind::Fn(..) | hir::ItemKind::TyAlias(..) => {
766 if item_level.is_some() {
767 self.reach(item.hir_id, item_level).generics().predicates().ty();
770 hir::ItemKind::Trait(.., ref trait_item_refs) => {
771 if item_level.is_some() {
772 self.reach(item.hir_id, item_level).generics().predicates();
774 for trait_item_ref in trait_item_refs {
775 let mut reach = self.reach(trait_item_ref.id.hir_id, item_level);
776 reach.generics().predicates();
778 if trait_item_ref.kind == AssocItemKind::Type &&
779 !trait_item_ref.defaultness.has_value() {
787 hir::ItemKind::TraitAlias(..) => {
788 if item_level.is_some() {
789 self.reach(item.hir_id, item_level).generics().predicates();
792 // Visit everything except for private impl items.
793 hir::ItemKind::Impl(.., ref impl_item_refs) => {
794 if item_level.is_some() {
795 self.reach(item.hir_id, item_level).generics().predicates().ty().trait_ref();
797 for impl_item_ref in impl_item_refs {
798 let impl_item_level = self.get(impl_item_ref.id.hir_id);
799 if impl_item_level.is_some() {
800 self.reach(impl_item_ref.id.hir_id, impl_item_level)
801 .generics().predicates().ty();
807 // Visit everything, but enum variants have their own levels.
808 hir::ItemKind::Enum(ref def, _) => {
809 if item_level.is_some() {
810 self.reach(item.hir_id, item_level).generics().predicates();
812 for variant in &def.variants {
813 let variant_level = self.get(variant.node.id);
814 if variant_level.is_some() {
815 for field in variant.node.data.fields() {
816 self.reach(field.hir_id, variant_level).ty();
818 // Corner case: if the variant is reachable, but its
819 // enum is not, make the enum reachable as well.
820 self.update(item.hir_id, variant_level);
824 // Visit everything, but foreign items have their own levels.
825 hir::ItemKind::ForeignMod(ref foreign_mod) => {
826 for foreign_item in &foreign_mod.items {
827 let foreign_item_level = self.get(foreign_item.hir_id);
828 if foreign_item_level.is_some() {
829 self.reach(foreign_item.hir_id, foreign_item_level)
830 .generics().predicates().ty();
834 // Visit everything except for private fields.
835 hir::ItemKind::Struct(ref struct_def, _) |
836 hir::ItemKind::Union(ref struct_def, _) => {
837 if item_level.is_some() {
838 self.reach(item.hir_id, item_level).generics().predicates();
839 for field in struct_def.fields() {
840 let field_level = self.get(field.hir_id);
841 if field_level.is_some() {
842 self.reach(field.hir_id, field_level).ty();
849 let orig_level = mem::replace(&mut self.prev_level, item_level);
850 intravisit::walk_item(self, item);
851 self.prev_level = orig_level;
854 fn visit_block(&mut self, b: &'tcx hir::Block) {
855 // Blocks can have public items, for example impls, but they always
856 // start as completely private regardless of publicity of a function,
857 // constant, type, field, etc., in which this block resides.
858 let orig_level = mem::replace(&mut self.prev_level, None);
859 intravisit::walk_block(self, b);
860 self.prev_level = orig_level;
863 fn visit_mod(&mut self, m: &'tcx hir::Mod, _sp: Span, id: hir::HirId) {
864 // This code is here instead of in visit_item so that the
865 // crate module gets processed as well.
866 if self.prev_level.is_some() {
867 let def_id = self.tcx.hir().local_def_id(id);
868 if let Some(exports) = self.tcx.module_exports(def_id) {
869 for export in exports.iter() {
870 if export.vis == ty::Visibility::Public {
871 if let Some(def_id) = export.res.opt_def_id() {
872 if let Some(hir_id) = self.tcx.hir().as_local_hir_id(def_id) {
873 self.update(hir_id, Some(AccessLevel::Exported));
881 intravisit::walk_mod(self, m, id);
884 fn visit_macro_def(&mut self, md: &'tcx hir::MacroDef) {
885 if attr::find_transparency(&md.attrs, md.legacy).0 != Transparency::Opaque {
886 self.update(md.hir_id, Some(AccessLevel::Public));
890 let macro_module_def_id = ty::DefIdTree::parent(
892 self.tcx.hir().local_def_id(md.hir_id)
894 let mut module_id = self.tcx.hir().as_local_hir_id(macro_module_def_id).unwrap();
895 let level = if md.vis.node.is_pub() { self.get(module_id) } else { None };
896 let new_level = self.update(md.hir_id, level);
897 if new_level.is_none() {
902 let changed_reachability = self.update_macro_reachable(module_id, macro_module_def_id);
903 if changed_reachability || module_id == hir::CRATE_HIR_ID {
906 module_id = self.tcx.hir().get_parent_node(module_id);
911 impl ReachEverythingInTheInterfaceVisitor<'_, 'tcx> {
912 fn generics(&mut self) -> &mut Self {
913 for param in &self.ev.tcx.generics_of(self.item_def_id).params {
915 GenericParamDefKind::Lifetime => {}
916 GenericParamDefKind::Type { has_default, .. } => {
918 self.visit(self.ev.tcx.type_of(param.def_id));
921 GenericParamDefKind::Const => {
922 self.visit(self.ev.tcx.type_of(param.def_id));
929 fn predicates(&mut self) -> &mut Self {
930 self.visit_predicates(self.ev.tcx.predicates_of(self.item_def_id));
934 fn ty(&mut self) -> &mut Self {
935 self.visit(self.ev.tcx.type_of(self.item_def_id));
939 fn trait_ref(&mut self) -> &mut Self {
940 if let Some(trait_ref) = self.ev.tcx.impl_trait_ref(self.item_def_id) {
941 self.visit_trait(trait_ref);
947 impl DefIdVisitor<'tcx> for ReachEverythingInTheInterfaceVisitor<'_, 'tcx> {
948 fn tcx(&self) -> TyCtxt<'tcx> { self.ev.tcx }
949 fn visit_def_id(&mut self, def_id: DefId, _kind: &str, _descr: &dyn fmt::Display) -> bool {
950 if let Some(hir_id) = self.ev.tcx.hir().as_local_hir_id(def_id) {
951 if let ((ty::Visibility::Public, ..), _)
952 | (_, Some(AccessLevel::ReachableFromImplTrait))
953 = (def_id_visibility(self.tcx(), def_id), self.access_level)
955 self.ev.update(hir_id, self.access_level);
962 //////////////////////////////////////////////////////////////////////////////////////
963 /// Name privacy visitor, checks privacy and reports violations.
964 /// Most of name privacy checks are performed during the main resolution phase,
965 /// or later in type checking when field accesses and associated items are resolved.
966 /// This pass performs remaining checks for fields in struct expressions and patterns.
967 //////////////////////////////////////////////////////////////////////////////////////
969 struct NamePrivacyVisitor<'a, 'tcx> {
971 tables: &'a ty::TypeckTables<'tcx>,
972 current_item: hir::HirId,
973 empty_tables: &'a ty::TypeckTables<'tcx>,
976 impl<'a, 'tcx> NamePrivacyVisitor<'a, 'tcx> {
977 // Checks that a field in a struct constructor (expression or pattern) is accessible.
978 fn check_field(&mut self,
979 use_ctxt: Span, // syntax context of the field name at the use site
980 span: Span, // span of the field pattern, e.g., `x: 0`
981 def: &'tcx ty::AdtDef, // definition of the struct or enum
982 field: &'tcx ty::FieldDef) { // definition of the field
983 let ident = Ident::new(kw::Invalid, use_ctxt);
984 let current_hir = self.current_item;
985 let def_id = self.tcx.adjust_ident_and_get_scope(ident, def.did, current_hir).1;
986 if !def.is_enum() && !field.vis.is_accessible_from(def_id, self.tcx) {
987 struct_span_err!(self.tcx.sess, span, E0451, "field `{}` of {} `{}` is private",
988 field.ident, def.variant_descr(), self.tcx.def_path_str(def.did))
989 .span_label(span, format!("field `{}` is private", field.ident))
995 impl<'a, 'tcx> Visitor<'tcx> for NamePrivacyVisitor<'a, 'tcx> {
996 /// We want to visit items in the context of their containing
997 /// module and so forth, so supply a crate for doing a deep walk.
998 fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> {
999 NestedVisitorMap::All(&self.tcx.hir())
1002 fn visit_mod(&mut self, _m: &'tcx hir::Mod, _s: Span, _n: hir::HirId) {
1003 // Don't visit nested modules, since we run a separate visitor walk
1004 // for each module in `privacy_access_levels`
1007 fn visit_nested_body(&mut self, body: hir::BodyId) {
1008 let orig_tables = mem::replace(&mut self.tables, self.tcx.body_tables(body));
1009 let body = self.tcx.hir().body(body);
1010 self.visit_body(body);
1011 self.tables = orig_tables;
1014 fn visit_item(&mut self, item: &'tcx hir::Item) {
1015 let orig_current_item = mem::replace(&mut self.current_item, item.hir_id);
1017 mem::replace(&mut self.tables, item_tables(self.tcx, item.hir_id, self.empty_tables));
1018 intravisit::walk_item(self, item);
1019 self.current_item = orig_current_item;
1020 self.tables = orig_tables;
1023 fn visit_trait_item(&mut self, ti: &'tcx hir::TraitItem) {
1025 mem::replace(&mut self.tables, item_tables(self.tcx, ti.hir_id, self.empty_tables));
1026 intravisit::walk_trait_item(self, ti);
1027 self.tables = orig_tables;
1030 fn visit_impl_item(&mut self, ii: &'tcx hir::ImplItem) {
1032 mem::replace(&mut self.tables, item_tables(self.tcx, ii.hir_id, self.empty_tables));
1033 intravisit::walk_impl_item(self, ii);
1034 self.tables = orig_tables;
1037 fn visit_expr(&mut self, expr: &'tcx hir::Expr) {
1039 hir::ExprKind::Struct(ref qpath, ref fields, ref base) => {
1040 let res = self.tables.qpath_res(qpath, expr.hir_id);
1041 let adt = self.tables.expr_ty(expr).ty_adt_def().unwrap();
1042 let variant = adt.variant_of_res(res);
1043 if let Some(ref base) = *base {
1044 // If the expression uses FRU we need to make sure all the unmentioned fields
1045 // are checked for privacy (RFC 736). Rather than computing the set of
1046 // unmentioned fields, just check them all.
1047 for (vf_index, variant_field) in variant.fields.iter().enumerate() {
1048 let field = fields.iter().find(|f| {
1049 self.tcx.field_index(f.hir_id, self.tables) == vf_index
1051 let (use_ctxt, span) = match field {
1052 Some(field) => (field.ident.span, field.span),
1053 None => (base.span, base.span),
1055 self.check_field(use_ctxt, span, adt, variant_field);
1058 for field in fields {
1059 let use_ctxt = field.ident.span;
1060 let index = self.tcx.field_index(field.hir_id, self.tables);
1061 self.check_field(use_ctxt, field.span, adt, &variant.fields[index]);
1068 intravisit::walk_expr(self, expr);
1071 fn visit_pat(&mut self, pat: &'tcx hir::Pat) {
1073 PatKind::Struct(ref qpath, ref fields, _) => {
1074 let res = self.tables.qpath_res(qpath, pat.hir_id);
1075 let adt = self.tables.pat_ty(pat).ty_adt_def().unwrap();
1076 let variant = adt.variant_of_res(res);
1077 for field in fields {
1078 let use_ctxt = field.node.ident.span;
1079 let index = self.tcx.field_index(field.node.hir_id, self.tables);
1080 self.check_field(use_ctxt, field.span, adt, &variant.fields[index]);
1086 intravisit::walk_pat(self, pat);
1090 ////////////////////////////////////////////////////////////////////////////////////////////
1091 /// Type privacy visitor, checks types for privacy and reports violations.
1092 /// Both explicitly written types and inferred types of expressions and patters are checked.
1093 /// Checks are performed on "semantic" types regardless of names and their hygiene.
1094 ////////////////////////////////////////////////////////////////////////////////////////////
1096 struct TypePrivacyVisitor<'a, 'tcx> {
1098 tables: &'a ty::TypeckTables<'tcx>,
1099 current_item: DefId,
1102 empty_tables: &'a ty::TypeckTables<'tcx>,
1105 impl<'a, 'tcx> TypePrivacyVisitor<'a, 'tcx> {
1106 fn item_is_accessible(&self, did: DefId) -> bool {
1107 def_id_visibility(self.tcx, did).0.is_accessible_from(self.current_item, self.tcx)
1110 // Take node-id of an expression or pattern and check its type for privacy.
1111 fn check_expr_pat_type(&mut self, id: hir::HirId, span: Span) -> bool {
1113 if self.visit(self.tables.node_type(id)) || self.visit(self.tables.node_substs(id)) {
1116 if let Some(adjustments) = self.tables.adjustments().get(id) {
1117 for adjustment in adjustments {
1118 if self.visit(adjustment.target) {
1126 fn check_def_id(&mut self, def_id: DefId, kind: &str, descr: &dyn fmt::Display) -> bool {
1127 let is_error = !self.item_is_accessible(def_id);
1129 self.tcx.sess.span_err(self.span, &format!("{} `{}` is private", kind, descr));
1135 impl<'a, 'tcx> Visitor<'tcx> for TypePrivacyVisitor<'a, 'tcx> {
1136 /// We want to visit items in the context of their containing
1137 /// module and so forth, so supply a crate for doing a deep walk.
1138 fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> {
1139 NestedVisitorMap::All(&self.tcx.hir())
1142 fn visit_mod(&mut self, _m: &'tcx hir::Mod, _s: Span, _n: hir::HirId) {
1143 // Don't visit nested modules, since we run a separate visitor walk
1144 // for each module in `privacy_access_levels`
1147 fn visit_nested_body(&mut self, body: hir::BodyId) {
1148 let orig_tables = mem::replace(&mut self.tables, self.tcx.body_tables(body));
1149 let orig_in_body = mem::replace(&mut self.in_body, true);
1150 let body = self.tcx.hir().body(body);
1151 self.visit_body(body);
1152 self.tables = orig_tables;
1153 self.in_body = orig_in_body;
1156 fn visit_ty(&mut self, hir_ty: &'tcx hir::Ty) {
1157 self.span = hir_ty.span;
1160 if self.visit(self.tables.node_type(hir_ty.hir_id)) {
1164 // Types in signatures.
1165 // FIXME: This is very ineffective. Ideally each HIR type should be converted
1166 // into a semantic type only once and the result should be cached somehow.
1167 if self.visit(rustc_typeck::hir_ty_to_ty(self.tcx, hir_ty)) {
1172 intravisit::walk_ty(self, hir_ty);
1175 fn visit_trait_ref(&mut self, trait_ref: &'tcx hir::TraitRef) {
1176 self.span = trait_ref.path.span;
1178 // Avoid calling `hir_trait_to_predicates` in bodies, it will ICE.
1179 // The traits' privacy in bodies is already checked as a part of trait object types.
1180 let bounds = rustc_typeck::hir_trait_to_predicates(self.tcx, trait_ref);
1182 for (trait_predicate, _) in bounds.trait_bounds {
1183 if self.visit_trait(*trait_predicate.skip_binder()) {
1188 for (poly_predicate, _) in bounds.projection_bounds {
1190 if self.visit(poly_predicate.skip_binder().ty)
1191 || self.visit_trait(poly_predicate.skip_binder().projection_ty.trait_ref(tcx))
1198 intravisit::walk_trait_ref(self, trait_ref);
1201 // Check types of expressions
1202 fn visit_expr(&mut self, expr: &'tcx hir::Expr) {
1203 if self.check_expr_pat_type(expr.hir_id, expr.span) {
1204 // Do not check nested expressions if the error already happened.
1208 hir::ExprKind::Assign(.., ref rhs) | hir::ExprKind::Match(ref rhs, ..) => {
1209 // Do not report duplicate errors for `x = y` and `match x { ... }`.
1210 if self.check_expr_pat_type(rhs.hir_id, rhs.span) {
1214 hir::ExprKind::MethodCall(_, span, _) => {
1215 // Method calls have to be checked specially.
1217 if let Some(def_id) = self.tables.type_dependent_def_id(expr.hir_id) {
1218 if self.visit(self.tcx.type_of(def_id)) {
1222 self.tcx.sess.delay_span_bug(expr.span,
1223 "no type-dependent def for method call");
1229 intravisit::walk_expr(self, expr);
1232 // Prohibit access to associated items with insufficient nominal visibility.
1234 // Additionally, until better reachability analysis for macros 2.0 is available,
1235 // we prohibit access to private statics from other crates, this allows to give
1236 // more code internal visibility at link time. (Access to private functions
1237 // is already prohibited by type privacy for function types.)
1238 fn visit_qpath(&mut self, qpath: &'tcx hir::QPath, id: hir::HirId, span: Span) {
1239 let def = match self.tables.qpath_res(qpath, id) {
1240 Res::Def(kind, def_id) => Some((kind, def_id)),
1243 let def = def.filter(|(kind, _)| {
1246 | DefKind::AssocConst
1248 | DefKind::AssocOpaqueTy
1249 | DefKind::Static => true,
1253 if let Some((kind, def_id)) = def {
1254 let is_local_static = if let DefKind::Static = kind {
1257 if !self.item_is_accessible(def_id) && !is_local_static {
1258 let name = match *qpath {
1259 hir::QPath::Resolved(_, ref path) => path.to_string(),
1260 hir::QPath::TypeRelative(_, ref segment) => segment.ident.to_string(),
1262 let msg = format!("{} `{}` is private", kind.descr(def_id), name);
1263 self.tcx.sess.span_err(span, &msg);
1268 intravisit::walk_qpath(self, qpath, id, span);
1271 // Check types of patterns.
1272 fn visit_pat(&mut self, pattern: &'tcx hir::Pat) {
1273 if self.check_expr_pat_type(pattern.hir_id, pattern.span) {
1274 // Do not check nested patterns if the error already happened.
1278 intravisit::walk_pat(self, pattern);
1281 fn visit_local(&mut self, local: &'tcx hir::Local) {
1282 if let Some(ref init) = local.init {
1283 if self.check_expr_pat_type(init.hir_id, init.span) {
1284 // Do not report duplicate errors for `let x = y`.
1289 intravisit::walk_local(self, local);
1292 // Check types in item interfaces.
1293 fn visit_item(&mut self, item: &'tcx hir::Item) {
1294 let orig_current_item = mem::replace(&mut self.current_item,
1295 self.tcx.hir().local_def_id(item.hir_id));
1296 let orig_in_body = mem::replace(&mut self.in_body, false);
1298 mem::replace(&mut self.tables, item_tables(self.tcx, item.hir_id, self.empty_tables));
1299 intravisit::walk_item(self, item);
1300 self.tables = orig_tables;
1301 self.in_body = orig_in_body;
1302 self.current_item = orig_current_item;
1305 fn visit_trait_item(&mut self, ti: &'tcx hir::TraitItem) {
1307 mem::replace(&mut self.tables, item_tables(self.tcx, ti.hir_id, self.empty_tables));
1308 intravisit::walk_trait_item(self, ti);
1309 self.tables = orig_tables;
1312 fn visit_impl_item(&mut self, ii: &'tcx hir::ImplItem) {
1314 mem::replace(&mut self.tables, item_tables(self.tcx, ii.hir_id, self.empty_tables));
1315 intravisit::walk_impl_item(self, ii);
1316 self.tables = orig_tables;
1320 impl DefIdVisitor<'tcx> for TypePrivacyVisitor<'a, 'tcx> {
1321 fn tcx(&self) -> TyCtxt<'tcx> { self.tcx }
1322 fn visit_def_id(&mut self, def_id: DefId, kind: &str, descr: &dyn fmt::Display) -> bool {
1323 self.check_def_id(def_id, kind, descr)
1327 ///////////////////////////////////////////////////////////////////////////////
1328 /// Obsolete visitors for checking for private items in public interfaces.
1329 /// These visitors are supposed to be kept in frozen state and produce an
1330 /// "old error node set". For backward compatibility the new visitor reports
1331 /// warnings instead of hard errors when the erroneous node is not in this old set.
1332 ///////////////////////////////////////////////////////////////////////////////
1334 struct ObsoleteVisiblePrivateTypesVisitor<'a, 'tcx> {
1336 access_levels: &'a AccessLevels,
1338 // Set of errors produced by this obsolete visitor.
1339 old_error_set: HirIdSet,
1342 struct ObsoleteCheckTypeForPrivatenessVisitor<'a, 'b, 'tcx> {
1343 inner: &'a ObsoleteVisiblePrivateTypesVisitor<'b, 'tcx>,
1344 /// Whether the type refers to private types.
1345 contains_private: bool,
1346 /// Whether we've recurred at all (i.e., if we're pointing at the
1347 /// first type on which `visit_ty` was called).
1348 at_outer_type: bool,
1349 /// Whether that first type is a public path.
1350 outer_type_is_public_path: bool,
1353 impl<'a, 'tcx> ObsoleteVisiblePrivateTypesVisitor<'a, 'tcx> {
1354 fn path_is_private_type(&self, path: &hir::Path) -> bool {
1355 let did = match path.res {
1356 Res::PrimTy(..) | Res::SelfTy(..) | Res::Err => return false,
1357 res => res.def_id(),
1360 // A path can only be private if:
1361 // it's in this crate...
1362 if let Some(hir_id) = self.tcx.hir().as_local_hir_id(did) {
1363 // .. and it corresponds to a private type in the AST (this returns
1364 // `None` for type parameters).
1365 match self.tcx.hir().find(hir_id) {
1366 Some(Node::Item(ref item)) => !item.vis.node.is_pub(),
1367 Some(_) | None => false,
1374 fn trait_is_public(&self, trait_id: hir::HirId) -> bool {
1375 // FIXME: this would preferably be using `exported_items`, but all
1376 // traits are exported currently (see `EmbargoVisitor.exported_trait`).
1377 self.access_levels.is_public(trait_id)
1380 fn check_generic_bound(&mut self, bound: &hir::GenericBound) {
1381 if let hir::GenericBound::Trait(ref trait_ref, _) = *bound {
1382 if self.path_is_private_type(&trait_ref.trait_ref.path) {
1383 self.old_error_set.insert(trait_ref.trait_ref.hir_ref_id);
1388 fn item_is_public(&self, id: &hir::HirId, vis: &hir::Visibility) -> bool {
1389 self.access_levels.is_reachable(*id) || vis.node.is_pub()
1393 impl<'a, 'b, 'tcx, 'v> Visitor<'v> for ObsoleteCheckTypeForPrivatenessVisitor<'a, 'b, 'tcx> {
1394 fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'v> {
1395 NestedVisitorMap::None
1398 fn visit_ty(&mut self, ty: &hir::Ty) {
1399 if let hir::TyKind::Path(hir::QPath::Resolved(_, ref path)) = ty.node {
1400 if self.inner.path_is_private_type(path) {
1401 self.contains_private = true;
1402 // Found what we're looking for, so let's stop working.
1406 if let hir::TyKind::Path(_) = ty.node {
1407 if self.at_outer_type {
1408 self.outer_type_is_public_path = true;
1411 self.at_outer_type = false;
1412 intravisit::walk_ty(self, ty)
1415 // Don't want to recurse into `[, .. expr]`.
1416 fn visit_expr(&mut self, _: &hir::Expr) {}
1419 impl<'a, 'tcx> Visitor<'tcx> for ObsoleteVisiblePrivateTypesVisitor<'a, 'tcx> {
1420 /// We want to visit items in the context of their containing
1421 /// module and so forth, so supply a crate for doing a deep walk.
1422 fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> {
1423 NestedVisitorMap::All(&self.tcx.hir())
1426 fn visit_item(&mut self, item: &'tcx hir::Item) {
1428 // Contents of a private mod can be re-exported, so we need
1429 // to check internals.
1430 hir::ItemKind::Mod(_) => {}
1432 // An `extern {}` doesn't introduce a new privacy
1433 // namespace (the contents have their own privacies).
1434 hir::ItemKind::ForeignMod(_) => {}
1436 hir::ItemKind::Trait(.., ref bounds, _) => {
1437 if !self.trait_is_public(item.hir_id) {
1441 for bound in bounds.iter() {
1442 self.check_generic_bound(bound)
1446 // Impls need some special handling to try to offer useful
1447 // error messages without (too many) false positives
1448 // (i.e., we could just return here to not check them at
1449 // all, or some worse estimation of whether an impl is
1450 // publicly visible).
1451 hir::ItemKind::Impl(.., ref g, ref trait_ref, ref self_, ref impl_item_refs) => {
1452 // `impl [... for] Private` is never visible.
1453 let self_contains_private;
1454 // `impl [... for] Public<...>`, but not `impl [... for]
1455 // Vec<Public>` or `(Public,)`, etc.
1456 let self_is_public_path;
1458 // Check the properties of the `Self` type:
1460 let mut visitor = ObsoleteCheckTypeForPrivatenessVisitor {
1462 contains_private: false,
1463 at_outer_type: true,
1464 outer_type_is_public_path: false,
1466 visitor.visit_ty(&self_);
1467 self_contains_private = visitor.contains_private;
1468 self_is_public_path = visitor.outer_type_is_public_path;
1471 // Miscellaneous info about the impl:
1473 // `true` iff this is `impl Private for ...`.
1474 let not_private_trait =
1475 trait_ref.as_ref().map_or(true, // no trait counts as public trait
1477 let did = tr.path.res.def_id();
1479 if let Some(hir_id) = self.tcx.hir().as_local_hir_id(did) {
1480 self.trait_is_public(hir_id)
1482 true // external traits must be public
1486 // `true` iff this is a trait impl or at least one method is public.
1488 // `impl Public { $( fn ...() {} )* }` is not visible.
1490 // This is required over just using the methods' privacy
1491 // directly because we might have `impl<T: Foo<Private>> ...`,
1492 // and we shouldn't warn about the generics if all the methods
1493 // are private (because `T` won't be visible externally).
1494 let trait_or_some_public_method =
1495 trait_ref.is_some() ||
1496 impl_item_refs.iter()
1497 .any(|impl_item_ref| {
1498 let impl_item = self.tcx.hir().impl_item(impl_item_ref.id);
1499 match impl_item.node {
1500 hir::ImplItemKind::Const(..) |
1501 hir::ImplItemKind::Method(..) => {
1502 self.access_levels.is_reachable(
1503 impl_item_ref.id.hir_id)
1505 hir::ImplItemKind::OpaqueTy(..) |
1506 hir::ImplItemKind::TyAlias(_) => false,
1510 if !self_contains_private &&
1511 not_private_trait &&
1512 trait_or_some_public_method {
1514 intravisit::walk_generics(self, g);
1518 for impl_item_ref in impl_item_refs {
1519 // This is where we choose whether to walk down
1520 // further into the impl to check its items. We
1521 // should only walk into public items so that we
1522 // don't erroneously report errors for private
1523 // types in private items.
1524 let impl_item = self.tcx.hir().impl_item(impl_item_ref.id);
1525 match impl_item.node {
1526 hir::ImplItemKind::Const(..) |
1527 hir::ImplItemKind::Method(..)
1528 if self.item_is_public(&impl_item.hir_id, &impl_item.vis) =>
1530 intravisit::walk_impl_item(self, impl_item)
1532 hir::ImplItemKind::TyAlias(..) => {
1533 intravisit::walk_impl_item(self, impl_item)
1540 // Any private types in a trait impl fall into three
1542 // 1. mentioned in the trait definition
1543 // 2. mentioned in the type params/generics
1544 // 3. mentioned in the associated types of the impl
1546 // Those in 1. can only occur if the trait is in
1547 // this crate and will've been warned about on the
1548 // trait definition (there's no need to warn twice
1549 // so we don't check the methods).
1551 // Those in 2. are warned via walk_generics and this
1553 intravisit::walk_path(self, &tr.path);
1555 // Those in 3. are warned with this call.
1556 for impl_item_ref in impl_item_refs {
1557 let impl_item = self.tcx.hir().impl_item(impl_item_ref.id);
1558 if let hir::ImplItemKind::TyAlias(ref ty) = impl_item.node {
1564 } else if trait_ref.is_none() && self_is_public_path {
1565 // `impl Public<Private> { ... }`. Any public static
1566 // methods will be visible as `Public::foo`.
1567 let mut found_pub_static = false;
1568 for impl_item_ref in impl_item_refs {
1569 if self.item_is_public(&impl_item_ref.id.hir_id, &impl_item_ref.vis) {
1570 let impl_item = self.tcx.hir().impl_item(impl_item_ref.id);
1571 match impl_item_ref.kind {
1572 AssocItemKind::Const => {
1573 found_pub_static = true;
1574 intravisit::walk_impl_item(self, impl_item);
1576 AssocItemKind::Method { has_self: false } => {
1577 found_pub_static = true;
1578 intravisit::walk_impl_item(self, impl_item);
1584 if found_pub_static {
1585 intravisit::walk_generics(self, g)
1591 // `type ... = ...;` can contain private types, because
1592 // we're introducing a new name.
1593 hir::ItemKind::TyAlias(..) => return,
1595 // Not at all public, so we don't care.
1596 _ if !self.item_is_public(&item.hir_id, &item.vis) => {
1603 // We've carefully constructed it so that if we're here, then
1604 // any `visit_ty`'s will be called on things that are in
1605 // public signatures, i.e., things that we're interested in for
1607 intravisit::walk_item(self, item);
1610 fn visit_generics(&mut self, generics: &'tcx hir::Generics) {
1611 for param in &generics.params {
1612 for bound in ¶m.bounds {
1613 self.check_generic_bound(bound);
1616 for predicate in &generics.where_clause.predicates {
1618 hir::WherePredicate::BoundPredicate(bound_pred) => {
1619 for bound in bound_pred.bounds.iter() {
1620 self.check_generic_bound(bound)
1623 hir::WherePredicate::RegionPredicate(_) => {}
1624 hir::WherePredicate::EqPredicate(eq_pred) => {
1625 self.visit_ty(&eq_pred.rhs_ty);
1631 fn visit_foreign_item(&mut self, item: &'tcx hir::ForeignItem) {
1632 if self.access_levels.is_reachable(item.hir_id) {
1633 intravisit::walk_foreign_item(self, item)
1637 fn visit_ty(&mut self, t: &'tcx hir::Ty) {
1638 if let hir::TyKind::Path(hir::QPath::Resolved(_, ref path)) = t.node {
1639 if self.path_is_private_type(path) {
1640 self.old_error_set.insert(t.hir_id);
1643 intravisit::walk_ty(self, t)
1646 fn visit_variant(&mut self,
1647 v: &'tcx hir::Variant,
1648 g: &'tcx hir::Generics,
1649 item_id: hir::HirId) {
1650 if self.access_levels.is_reachable(v.node.id) {
1651 self.in_variant = true;
1652 intravisit::walk_variant(self, v, g, item_id);
1653 self.in_variant = false;
1657 fn visit_struct_field(&mut self, s: &'tcx hir::StructField) {
1658 if s.vis.node.is_pub() || self.in_variant {
1659 intravisit::walk_struct_field(self, s);
1663 // We don't need to introspect into these at all: an
1664 // expression/block context can't possibly contain exported things.
1665 // (Making them no-ops stops us from traversing the whole AST without
1666 // having to be super careful about our `walk_...` calls above.)
1667 fn visit_block(&mut self, _: &'tcx hir::Block) {}
1668 fn visit_expr(&mut self, _: &'tcx hir::Expr) {}
1671 ///////////////////////////////////////////////////////////////////////////////
1672 /// SearchInterfaceForPrivateItemsVisitor traverses an item's interface and
1673 /// finds any private components in it.
1674 /// PrivateItemsInPublicInterfacesVisitor ensures there are no private types
1675 /// and traits in public interfaces.
1676 ///////////////////////////////////////////////////////////////////////////////
1678 struct SearchInterfaceForPrivateItemsVisitor<'tcx> {
1680 item_id: hir::HirId,
1683 /// The visitor checks that each component type is at least this visible.
1684 required_visibility: ty::Visibility,
1685 has_pub_restricted: bool,
1686 has_old_errors: bool,
1690 impl SearchInterfaceForPrivateItemsVisitor<'tcx> {
1691 fn generics(&mut self) -> &mut Self {
1692 for param in &self.tcx.generics_of(self.item_def_id).params {
1694 GenericParamDefKind::Lifetime => {}
1695 GenericParamDefKind::Type { has_default, .. } => {
1697 self.visit(self.tcx.type_of(param.def_id));
1700 GenericParamDefKind::Const => {
1701 self.visit(self.tcx.type_of(param.def_id));
1708 fn predicates(&mut self) -> &mut Self {
1709 // N.B., we use `explicit_predicates_of` and not `predicates_of`
1710 // because we don't want to report privacy errors due to where
1711 // clauses that the compiler inferred. We only want to
1712 // consider the ones that the user wrote. This is important
1713 // for the inferred outlives rules; see
1714 // `src/test/ui/rfc-2093-infer-outlives/privacy.rs`.
1715 self.visit_predicates(self.tcx.explicit_predicates_of(self.item_def_id));
1719 fn ty(&mut self) -> &mut Self {
1720 self.visit(self.tcx.type_of(self.item_def_id));
1724 fn check_def_id(&mut self, def_id: DefId, kind: &str, descr: &dyn fmt::Display) -> bool {
1725 if self.leaks_private_dep(def_id) {
1726 self.tcx.lint_hir(lint::builtin::EXPORTED_PRIVATE_DEPENDENCIES,
1729 &format!("{} `{}` from private dependency '{}' in public \
1730 interface", kind, descr,
1731 self.tcx.crate_name(def_id.krate)));
1735 let hir_id = match self.tcx.hir().as_local_hir_id(def_id) {
1736 Some(hir_id) => hir_id,
1737 None => return false,
1740 let (vis, vis_span, vis_descr) = def_id_visibility(self.tcx, def_id);
1741 if !vis.is_at_least(self.required_visibility, self.tcx) {
1742 let msg = format!("{} {} `{}` in public interface", vis_descr, kind, descr);
1743 if self.has_pub_restricted || self.has_old_errors || self.in_assoc_ty {
1744 let mut err = if kind == "trait" {
1745 struct_span_err!(self.tcx.sess, self.span, E0445, "{}", msg)
1747 struct_span_err!(self.tcx.sess, self.span, E0446, "{}", msg)
1749 err.span_label(self.span, format!("can't leak {} {}", vis_descr, kind));
1750 err.span_label(vis_span, format!("`{}` declared as {}", descr, vis_descr));
1753 let err_code = if kind == "trait" { "E0445" } else { "E0446" };
1754 self.tcx.lint_hir(lint::builtin::PRIVATE_IN_PUBLIC, hir_id, self.span,
1755 &format!("{} (error {})", msg, err_code));
1763 /// An item is 'leaked' from a private dependency if all
1764 /// of the following are true:
1765 /// 1. It's contained within a public type
1766 /// 2. It comes from a private crate
1767 fn leaks_private_dep(&self, item_id: DefId) -> bool {
1768 let ret = self.required_visibility == ty::Visibility::Public &&
1769 self.tcx.is_private_dep(item_id.krate);
1771 log::debug!("leaks_private_dep(item_id={:?})={}", item_id, ret);
1776 impl DefIdVisitor<'tcx> for SearchInterfaceForPrivateItemsVisitor<'tcx> {
1777 fn tcx(&self) -> TyCtxt<'tcx> { self.tcx }
1778 fn visit_def_id(&mut self, def_id: DefId, kind: &str, descr: &dyn fmt::Display) -> bool {
1779 self.check_def_id(def_id, kind, descr)
1783 struct PrivateItemsInPublicInterfacesVisitor<'a, 'tcx> {
1785 has_pub_restricted: bool,
1786 old_error_set: &'a HirIdSet,
1789 impl<'a, 'tcx> PrivateItemsInPublicInterfacesVisitor<'a, 'tcx> {
1792 item_id: hir::HirId,
1793 required_visibility: ty::Visibility,
1794 ) -> SearchInterfaceForPrivateItemsVisitor<'tcx> {
1795 let mut has_old_errors = false;
1797 // Slow path taken only if there any errors in the crate.
1798 for &id in self.old_error_set {
1799 // Walk up the nodes until we find `item_id` (or we hit a root).
1803 has_old_errors = true;
1806 let parent = self.tcx.hir().get_parent_node(id);
1818 SearchInterfaceForPrivateItemsVisitor {
1821 item_def_id: self.tcx.hir().local_def_id(item_id),
1822 span: self.tcx.hir().span(item_id),
1823 required_visibility,
1824 has_pub_restricted: self.has_pub_restricted,
1830 fn check_assoc_item(
1833 assoc_item_kind: AssocItemKind,
1834 defaultness: hir::Defaultness,
1835 vis: ty::Visibility,
1837 let mut check = self.check(hir_id, vis);
1839 let (check_ty, is_assoc_ty) = match assoc_item_kind {
1840 AssocItemKind::Const | AssocItemKind::Method { .. } => (true, false),
1841 AssocItemKind::Type => (defaultness.has_value(), true),
1842 // `ty()` for opaque types is the underlying type,
1843 // it's not a part of interface, so we skip it.
1844 AssocItemKind::OpaqueTy => (false, true),
1846 check.in_assoc_ty = is_assoc_ty;
1847 check.generics().predicates();
1854 impl<'a, 'tcx> Visitor<'tcx> for PrivateItemsInPublicInterfacesVisitor<'a, 'tcx> {
1855 fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> {
1856 NestedVisitorMap::OnlyBodies(&self.tcx.hir())
1859 fn visit_item(&mut self, item: &'tcx hir::Item) {
1861 let item_visibility = ty::Visibility::from_hir(&item.vis, item.hir_id, tcx);
1864 // Crates are always public.
1865 hir::ItemKind::ExternCrate(..) => {}
1866 // All nested items are checked by `visit_item`.
1867 hir::ItemKind::Mod(..) => {}
1868 // Checked in resolve.
1869 hir::ItemKind::Use(..) => {}
1871 hir::ItemKind::GlobalAsm(..) => {}
1872 // Subitems of these items have inherited publicity.
1873 hir::ItemKind::Const(..) | hir::ItemKind::Static(..) |
1874 hir::ItemKind::Fn(..) | hir::ItemKind::TyAlias(..) => {
1875 self.check(item.hir_id, item_visibility).generics().predicates().ty();
1877 hir::ItemKind::OpaqueTy(..) => {
1878 // `ty()` for opaque types is the underlying type,
1879 // it's not a part of interface, so we skip it.
1880 self.check(item.hir_id, item_visibility).generics().predicates();
1882 hir::ItemKind::Trait(.., ref trait_item_refs) => {
1883 self.check(item.hir_id, item_visibility).generics().predicates();
1885 for trait_item_ref in trait_item_refs {
1886 self.check_assoc_item(
1887 trait_item_ref.id.hir_id,
1888 trait_item_ref.kind,
1889 trait_item_ref.defaultness,
1894 hir::ItemKind::TraitAlias(..) => {
1895 self.check(item.hir_id, item_visibility).generics().predicates();
1897 hir::ItemKind::Enum(ref def, _) => {
1898 self.check(item.hir_id, item_visibility).generics().predicates();
1900 for variant in &def.variants {
1901 for field in variant.node.data.fields() {
1902 self.check(field.hir_id, item_visibility).ty();
1906 // Subitems of foreign modules have their own publicity.
1907 hir::ItemKind::ForeignMod(ref foreign_mod) => {
1908 for foreign_item in &foreign_mod.items {
1909 let vis = ty::Visibility::from_hir(&foreign_item.vis, item.hir_id, tcx);
1910 self.check(foreign_item.hir_id, vis).generics().predicates().ty();
1913 // Subitems of structs and unions have their own publicity.
1914 hir::ItemKind::Struct(ref struct_def, _) |
1915 hir::ItemKind::Union(ref struct_def, _) => {
1916 self.check(item.hir_id, item_visibility).generics().predicates();
1918 for field in struct_def.fields() {
1919 let field_visibility = ty::Visibility::from_hir(&field.vis, item.hir_id, tcx);
1920 self.check(field.hir_id, min(item_visibility, field_visibility, tcx)).ty();
1923 // An inherent impl is public when its type is public
1924 // Subitems of inherent impls have their own publicity.
1925 // A trait impl is public when both its type and its trait are public
1926 // Subitems of trait impls have inherited publicity.
1927 hir::ItemKind::Impl(.., ref trait_ref, _, ref impl_item_refs) => {
1928 let impl_vis = ty::Visibility::of_impl(item.hir_id, tcx, &Default::default());
1929 self.check(item.hir_id, impl_vis).generics().predicates();
1930 for impl_item_ref in impl_item_refs {
1931 let impl_item = tcx.hir().impl_item(impl_item_ref.id);
1932 let impl_item_vis = if trait_ref.is_none() {
1933 min(ty::Visibility::from_hir(&impl_item.vis, item.hir_id, tcx),
1939 self.check_assoc_item(
1940 impl_item_ref.id.hir_id,
1942 impl_item_ref.defaultness,
1951 pub fn provide(providers: &mut Providers<'_>) {
1952 *providers = Providers {
1953 privacy_access_levels,
1954 check_private_in_public,
1960 fn check_mod_privacy(tcx: TyCtxt<'_>, module_def_id: DefId) {
1961 let empty_tables = ty::TypeckTables::empty(None);
1963 // Check privacy of names not checked in previous compilation stages.
1964 let mut visitor = NamePrivacyVisitor {
1966 tables: &empty_tables,
1967 current_item: hir::DUMMY_HIR_ID,
1968 empty_tables: &empty_tables,
1970 let (module, span, hir_id) = tcx.hir().get_module(module_def_id);
1972 intravisit::walk_mod(&mut visitor, module, hir_id);
1974 // Check privacy of explicitly written types and traits as well as
1975 // inferred types of expressions and patterns.
1976 let mut visitor = TypePrivacyVisitor {
1978 tables: &empty_tables,
1979 current_item: module_def_id,
1982 empty_tables: &empty_tables,
1984 intravisit::walk_mod(&mut visitor, module, hir_id);
1987 fn privacy_access_levels(tcx: TyCtxt<'_>, krate: CrateNum) -> &AccessLevels {
1988 assert_eq!(krate, LOCAL_CRATE);
1990 // Build up a set of all exported items in the AST. This is a set of all
1991 // items which are reachable from external crates based on visibility.
1992 let mut visitor = EmbargoVisitor {
1994 access_levels: Default::default(),
1995 macro_reachable: Default::default(),
1996 prev_level: Some(AccessLevel::Public),
2000 intravisit::walk_crate(&mut visitor, tcx.hir().krate());
2001 if visitor.changed {
2002 visitor.changed = false;
2007 visitor.update(hir::CRATE_HIR_ID, Some(AccessLevel::Public));
2009 tcx.arena.alloc(visitor.access_levels)
2012 fn check_private_in_public(tcx: TyCtxt<'_>, krate: CrateNum) {
2013 assert_eq!(krate, LOCAL_CRATE);
2015 let access_levels = tcx.privacy_access_levels(LOCAL_CRATE);
2017 let krate = tcx.hir().krate();
2019 let mut visitor = ObsoleteVisiblePrivateTypesVisitor {
2021 access_levels: &access_levels,
2023 old_error_set: Default::default(),
2025 intravisit::walk_crate(&mut visitor, krate);
2027 let has_pub_restricted = {
2028 let mut pub_restricted_visitor = PubRestrictedVisitor {
2030 has_pub_restricted: false
2032 intravisit::walk_crate(&mut pub_restricted_visitor, krate);
2033 pub_restricted_visitor.has_pub_restricted
2036 // Check for private types and traits in public interfaces.
2037 let mut visitor = PrivateItemsInPublicInterfacesVisitor {
2040 old_error_set: &visitor.old_error_set,
2042 krate.visit_all_item_likes(&mut DeepVisitor::new(&mut visitor));
2045 __build_diagnostic_array! { librustc_privacy, DIAGNOSTICS }