1 #![doc(html_root_url = "https://doc.rust-lang.org/nightly/")]
3 #![deny(rust_2018_idioms)]
6 #![feature(rustc_diagnostic_macros)]
8 #![recursion_limit="256"]
10 #[macro_use] extern crate syntax;
13 use rustc::hir::{self, Node, PatKind, AssociatedItemKind};
14 use rustc::hir::def::Def;
15 use rustc::hir::def_id::{CRATE_DEF_INDEX, LOCAL_CRATE, CrateNum, DefId};
16 use rustc::hir::intravisit::{self, Visitor, NestedVisitorMap};
17 use rustc::hir::itemlikevisit::DeepVisitor;
19 use rustc::middle::privacy::{AccessLevel, AccessLevels};
20 use rustc::ty::{self, TyCtxt, Ty, TraitRef, TypeFoldable, GenericParamDefKind};
21 use rustc::ty::fold::TypeVisitor;
22 use rustc::ty::query::Providers;
23 use rustc::ty::subst::Substs;
24 use rustc::util::nodemap::HirIdSet;
25 use rustc_data_structures::fx::FxHashSet;
26 use rustc_data_structures::sync::Lrc;
27 use syntax::ast::{self, DUMMY_NODE_ID, Ident};
29 use syntax::symbol::keywords;
32 use std::{cmp, fmt, mem};
33 use std::marker::PhantomData;
37 ////////////////////////////////////////////////////////////////////////////////
38 /// Generic infrastructure used to implement specific visitors below.
39 ////////////////////////////////////////////////////////////////////////////////
41 /// Implemented to visit all `DefId`s in a type.
42 /// Visiting `DefId`s is useful because visibilities and reachabilities are attached to them.
43 /// The idea is to visit "all components of a type", as documented in
44 /// https://github.com/rust-lang/rfcs/blob/master/text/2145-type-privacy.md#how-to-determine-visibility-of-a-type.
45 /// The default type visitor (`TypeVisitor`) does most of the job, but it has some shortcomings.
46 /// First, it doesn't have overridable `fn visit_trait_ref`, so we have to catch trait `DefId`s
47 /// manually. Second, it doesn't visit some type components like signatures of fn types, or traits
48 /// in `impl Trait`, see individual comments in `DefIdVisitorSkeleton::visit_ty`.
49 trait DefIdVisitor<'a, 'tcx: 'a> {
50 fn tcx(&self) -> TyCtxt<'a, 'tcx, 'tcx>;
51 fn shallow(&self) -> bool { false }
52 fn skip_assoc_tys(&self) -> bool { false }
53 fn visit_def_id(&mut self, def_id: DefId, kind: &str, descr: &dyn fmt::Display) -> bool;
55 /// Not overridden, but used to actually visit types and traits.
56 fn skeleton(&mut self) -> DefIdVisitorSkeleton<'_, 'a, 'tcx, Self> {
57 DefIdVisitorSkeleton {
59 visited_opaque_tys: Default::default(),
60 dummy: Default::default(),
63 fn visit(&mut self, ty_fragment: impl TypeFoldable<'tcx>) -> bool {
64 ty_fragment.visit_with(&mut self.skeleton())
66 fn visit_trait(&mut self, trait_ref: TraitRef<'tcx>) -> bool {
67 self.skeleton().visit_trait(trait_ref)
69 fn visit_predicates(&mut self, predicates: Lrc<ty::GenericPredicates<'tcx>>) -> bool {
70 self.skeleton().visit_predicates(predicates)
74 struct DefIdVisitorSkeleton<'v, 'a, 'tcx, V>
75 where V: DefIdVisitor<'a, 'tcx> + ?Sized
77 def_id_visitor: &'v mut V,
78 visited_opaque_tys: FxHashSet<DefId>,
79 dummy: PhantomData<TyCtxt<'a, 'tcx, 'tcx>>,
82 impl<'a, 'tcx, V> DefIdVisitorSkeleton<'_, 'a, 'tcx, V>
83 where V: DefIdVisitor<'a, 'tcx> + ?Sized
85 fn visit_trait(&mut self, trait_ref: TraitRef<'tcx>) -> bool {
86 let TraitRef { def_id, substs } = trait_ref;
87 self.def_id_visitor.visit_def_id(def_id, "trait", &trait_ref) ||
88 (!self.def_id_visitor.shallow() && substs.visit_with(self))
91 fn visit_predicates(&mut self, predicates: Lrc<ty::GenericPredicates<'tcx>>) -> bool {
92 let ty::GenericPredicates { parent: _, predicates } = &*predicates;
93 for (predicate, _span) in predicates {
95 ty::Predicate::Trait(poly_predicate) => {
96 let ty::TraitPredicate { trait_ref } = *poly_predicate.skip_binder();
97 if self.visit_trait(trait_ref) {
101 ty::Predicate::Projection(poly_predicate) => {
102 let ty::ProjectionPredicate { projection_ty, ty } =
103 *poly_predicate.skip_binder();
104 if ty.visit_with(self) {
107 if self.visit_trait(projection_ty.trait_ref(self.def_id_visitor.tcx())) {
111 ty::Predicate::TypeOutlives(poly_predicate) => {
112 let ty::OutlivesPredicate(ty, _region) = *poly_predicate.skip_binder();
113 if ty.visit_with(self) {
117 ty::Predicate::RegionOutlives(..) => {},
118 _ => bug!("unexpected predicate: {:?}", predicate),
125 impl<'a, 'tcx, V> TypeVisitor<'tcx> for DefIdVisitorSkeleton<'_, 'a, 'tcx, V>
126 where V: DefIdVisitor<'a, 'tcx> + ?Sized
128 fn visit_ty(&mut self, ty: Ty<'tcx>) -> bool {
129 let tcx = self.def_id_visitor.tcx();
130 // Substs are not visited here because they are visited below in `super_visit_with`.
132 ty::Adt(&ty::AdtDef { did: def_id, .. }, ..) |
133 ty::Foreign(def_id) |
134 ty::FnDef(def_id, ..) |
135 ty::Closure(def_id, ..) |
136 ty::Generator(def_id, ..) => {
137 if self.def_id_visitor.visit_def_id(def_id, "type", ty) {
140 if self.def_id_visitor.shallow() {
143 // Default type visitor doesn't visit signatures of fn types.
144 // Something like `fn() -> Priv {my_func}` is considered a private type even if
145 // `my_func` is public, so we need to visit signatures.
146 if let ty::FnDef(..) = ty.sty {
147 if tcx.fn_sig(def_id).visit_with(self) {
151 // Inherent static methods don't have self type in substs.
152 // Something like `fn() {my_method}` type of the method
153 // `impl Pub<Priv> { pub fn my_method() {} }` is considered a private type,
154 // so we need to visit the self type additionally.
155 if let Some(assoc_item) = tcx.opt_associated_item(def_id) {
156 if let ty::ImplContainer(impl_def_id) = assoc_item.container {
157 if tcx.type_of(impl_def_id).visit_with(self) {
163 ty::Projection(proj) | ty::UnnormalizedProjection(proj) => {
164 if self.def_id_visitor.skip_assoc_tys() {
165 // Visitors searching for minimal visibility/reachability want to
166 // conservatively approximate associated types like `<Type as Trait>::Alias`
167 // as visible/reachable even if both `Type` and `Trait` are private.
168 // Ideally, associated types should be substituted in the same way as
169 // free type aliases, but this isn't done yet.
172 // This will also visit substs if necessary, so we don't need to recurse.
173 return self.visit_trait(proj.trait_ref(tcx));
175 ty::Dynamic(predicates, ..) => {
176 // All traits in the list are considered the "primary" part of the type
177 // and are visited by shallow visitors.
178 for predicate in *predicates.skip_binder() {
179 let trait_ref = match *predicate {
180 ty::ExistentialPredicate::Trait(trait_ref) => trait_ref,
181 ty::ExistentialPredicate::Projection(proj) => proj.trait_ref(tcx),
182 ty::ExistentialPredicate::AutoTrait(def_id) =>
183 ty::ExistentialTraitRef { def_id, substs: Substs::empty() },
185 let ty::ExistentialTraitRef { def_id, substs: _ } = trait_ref;
186 if self.def_id_visitor.visit_def_id(def_id, "trait", &trait_ref) {
191 ty::Opaque(def_id, ..) => {
192 // Skip repeated `Opaque`s to avoid infinite recursion.
193 if self.visited_opaque_tys.insert(def_id) {
194 // The intent is to treat `impl Trait1 + Trait2` identically to
195 // `dyn Trait1 + Trait2`. Therefore we ignore def-id of the opaque type itself
196 // (it either has no visibility, or its visibility is insignificant, like
197 // visibilities of type aliases) and recurse into predicates instead to go
198 // through the trait list (default type visitor doesn't visit those traits).
199 // All traits in the list are considered the "primary" part of the type
200 // and are visited by shallow visitors.
201 if self.visit_predicates(tcx.predicates_of(def_id)) {
206 // These types don't have their own def-ids (but may have subcomponents
207 // with def-ids that should be visited recursively).
208 ty::Bool | ty::Char | ty::Int(..) | ty::Uint(..) |
209 ty::Float(..) | ty::Str | ty::Never |
210 ty::Array(..) | ty::Slice(..) | ty::Tuple(..) |
211 ty::RawPtr(..) | ty::Ref(..) | ty::FnPtr(..) |
212 ty::Param(..) | ty::Error | ty::GeneratorWitness(..) => {}
213 ty::Bound(..) | ty::Placeholder(..) | ty::Infer(..) =>
214 bug!("unexpected type: {:?}", ty),
217 !self.def_id_visitor.shallow() && ty.super_visit_with(self)
221 fn def_id_visibility<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>, def_id: DefId)
222 -> (ty::Visibility, Span, &'static str) {
223 match tcx.hir().as_local_node_id(def_id) {
225 let vis = match tcx.hir().get(node_id) {
226 Node::Item(item) => &item.vis,
227 Node::ForeignItem(foreign_item) => &foreign_item.vis,
228 Node::TraitItem(..) | Node::Variant(..) => {
229 return def_id_visibility(tcx, tcx.hir().get_parent_did(node_id));
231 Node::ImplItem(impl_item) => {
232 match tcx.hir().get(tcx.hir().get_parent(node_id)) {
233 Node::Item(item) => match &item.node {
234 hir::ItemKind::Impl(.., None, _, _) => &impl_item.vis,
235 hir::ItemKind::Impl(.., Some(trait_ref), _, _)
236 => return def_id_visibility(tcx, trait_ref.path.def.def_id()),
237 kind => bug!("unexpected item kind: {:?}", kind),
239 node => bug!("unexpected node kind: {:?}", node),
242 Node::StructCtor(vdata) => {
243 let struct_node_id = tcx.hir().get_parent(node_id);
244 let item = match tcx.hir().get(struct_node_id) {
245 Node::Item(item) => item,
246 node => bug!("unexpected node kind: {:?}", node),
248 let (mut ctor_vis, mut span, mut descr) =
249 (ty::Visibility::from_hir(&item.vis, struct_node_id, tcx),
250 item.vis.span, item.vis.node.descr());
251 for field in vdata.fields() {
252 let field_vis = ty::Visibility::from_hir(&field.vis, node_id, tcx);
253 if ctor_vis.is_at_least(field_vis, tcx) {
254 ctor_vis = field_vis;
255 span = field.vis.span;
256 descr = field.vis.node.descr();
260 // If the structure is marked as non_exhaustive then lower the
261 // visibility to within the crate.
262 if ctor_vis == ty::Visibility::Public {
263 let adt_def = tcx.adt_def(tcx.hir().get_parent_did(node_id));
264 if adt_def.non_enum_variant().is_field_list_non_exhaustive() {
265 ctor_vis = ty::Visibility::Restricted(DefId::local(CRATE_DEF_INDEX));
266 span = attr::find_by_name(&item.attrs, "non_exhaustive").unwrap().span;
267 descr = "crate-visible";
271 return (ctor_vis, span, descr);
273 Node::Expr(expr) => {
274 return (ty::Visibility::Restricted(
275 tcx.hir().get_module_parent_by_hir_id(expr.hir_id)),
276 expr.span, "private")
278 node => bug!("unexpected node kind: {:?}", node)
280 (ty::Visibility::from_hir(vis, node_id, tcx), vis.span, vis.node.descr())
283 let vis = tcx.visibility(def_id);
284 let descr = if vis == ty::Visibility::Public { "public" } else { "private" };
285 (vis, tcx.def_span(def_id), descr)
290 // Set the correct `TypeckTables` for the given `item_id` (or an empty table if
291 // there is no `TypeckTables` for the item).
292 fn item_tables<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
293 node_id: ast::NodeId,
294 empty_tables: &'a ty::TypeckTables<'tcx>)
295 -> &'a ty::TypeckTables<'tcx> {
296 let def_id = tcx.hir().local_def_id(node_id);
297 if tcx.has_typeck_tables(def_id) { tcx.typeck_tables_of(def_id) } else { empty_tables }
300 fn min<'a, 'tcx>(vis1: ty::Visibility, vis2: ty::Visibility, tcx: TyCtxt<'a, 'tcx, 'tcx>)
302 if vis1.is_at_least(vis2, tcx) { vis2 } else { vis1 }
305 ////////////////////////////////////////////////////////////////////////////////
306 /// Visitor used to determine if pub(restricted) is used anywhere in the crate.
308 /// This is done so that `private_in_public` warnings can be turned into hard errors
309 /// in crates that have been updated to use pub(restricted).
310 ////////////////////////////////////////////////////////////////////////////////
311 struct PubRestrictedVisitor<'a, 'tcx: 'a> {
312 tcx: TyCtxt<'a, 'tcx, 'tcx>,
313 has_pub_restricted: bool,
316 impl<'a, 'tcx> Visitor<'tcx> for PubRestrictedVisitor<'a, 'tcx> {
317 fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> {
318 NestedVisitorMap::All(&self.tcx.hir())
320 fn visit_vis(&mut self, vis: &'tcx hir::Visibility) {
321 self.has_pub_restricted = self.has_pub_restricted || vis.node.is_pub_restricted();
325 ////////////////////////////////////////////////////////////////////////////////
326 /// Visitor used to determine impl visibility and reachability.
327 ////////////////////////////////////////////////////////////////////////////////
329 struct FindMin<'a, 'tcx, VL: VisibilityLike> {
330 tcx: TyCtxt<'a, 'tcx, 'tcx>,
331 access_levels: &'a AccessLevels,
335 impl<'a, 'tcx, VL: VisibilityLike> DefIdVisitor<'a, 'tcx> for FindMin<'a, 'tcx, VL> {
336 fn tcx(&self) -> TyCtxt<'a, 'tcx, 'tcx> { self.tcx }
337 fn shallow(&self) -> bool { VL::SHALLOW }
338 fn skip_assoc_tys(&self) -> bool { true }
339 fn visit_def_id(&mut self, def_id: DefId, _kind: &str, _descr: &dyn fmt::Display) -> bool {
340 self.min = VL::new_min(self, def_id);
345 trait VisibilityLike: Sized {
347 const SHALLOW: bool = false;
348 fn new_min<'a, 'tcx>(find: &FindMin<'a, 'tcx, Self>, def_id: DefId) -> Self;
350 // Returns an over-approximation (`skip_assoc_tys` = true) of visibility due to
351 // associated types for which we can't determine visibility precisely.
352 fn of_impl<'a, 'tcx>(node_id: ast::NodeId, tcx: TyCtxt<'a, 'tcx, 'tcx>,
353 access_levels: &'a AccessLevels) -> Self {
354 let mut find = FindMin { tcx, access_levels, min: Self::MAX };
355 let def_id = tcx.hir().local_def_id(node_id);
356 find.visit(tcx.type_of(def_id));
357 if let Some(trait_ref) = tcx.impl_trait_ref(def_id) {
358 find.visit_trait(trait_ref);
363 impl VisibilityLike for ty::Visibility {
364 const MAX: Self = ty::Visibility::Public;
365 fn new_min<'a, 'tcx>(find: &FindMin<'a, 'tcx, Self>, def_id: DefId) -> Self {
366 min(def_id_visibility(find.tcx, def_id).0, find.min, find.tcx)
369 impl VisibilityLike for Option<AccessLevel> {
370 const MAX: Self = Some(AccessLevel::Public);
371 // Type inference is very smart sometimes.
372 // It can make an impl reachable even some components of its type or trait are unreachable.
373 // E.g. methods of `impl ReachableTrait<UnreachableTy> for ReachableTy<UnreachableTy> { ... }`
374 // can be usable from other crates (#57264). So we skip substs when calculating reachability
375 // and consider an impl reachable if its "shallow" type and trait are reachable.
377 // The assumption we make here is that type-inference won't let you use an impl without knowing
378 // both "shallow" version of its self type and "shallow" version of its trait if it exists
379 // (which require reaching the `DefId`s in them).
380 const SHALLOW: bool = true;
381 fn new_min<'a, 'tcx>(find: &FindMin<'a, 'tcx, Self>, def_id: DefId) -> Self {
382 cmp::min(if let Some(node_id) = find.tcx.hir().as_local_node_id(def_id) {
383 find.access_levels.map.get(&node_id).cloned()
390 ////////////////////////////////////////////////////////////////////////////////
391 /// The embargo visitor, used to determine the exports of the AST.
392 ////////////////////////////////////////////////////////////////////////////////
394 struct EmbargoVisitor<'a, 'tcx: 'a> {
395 tcx: TyCtxt<'a, 'tcx, 'tcx>,
397 // Accessibility levels for reachable nodes.
398 access_levels: AccessLevels,
399 // Previous accessibility level; `None` means unreachable.
400 prev_level: Option<AccessLevel>,
401 // Has something changed in the level map?
405 struct ReachEverythingInTheInterfaceVisitor<'b, 'a: 'b, 'tcx: 'a> {
406 access_level: Option<AccessLevel>,
408 ev: &'b mut EmbargoVisitor<'a, 'tcx>,
411 impl<'a, 'tcx> EmbargoVisitor<'a, 'tcx> {
412 fn get(&self, id: ast::NodeId) -> Option<AccessLevel> {
413 self.access_levels.map.get(&id).cloned()
416 // Updates node level and returns the updated level.
417 fn update(&mut self, id: ast::NodeId, level: Option<AccessLevel>) -> Option<AccessLevel> {
418 let old_level = self.get(id);
419 // Accessibility levels can only grow.
420 if level > old_level {
421 self.access_levels.map.insert(id, level.unwrap());
429 fn reach(&mut self, item_id: ast::NodeId, access_level: Option<AccessLevel>)
430 -> ReachEverythingInTheInterfaceVisitor<'_, 'a, 'tcx> {
431 ReachEverythingInTheInterfaceVisitor {
432 access_level: cmp::min(access_level, Some(AccessLevel::Reachable)),
433 item_def_id: self.tcx.hir().local_def_id(item_id),
439 /// Given the path segments of a `ItemKind::Use`, then we need
440 /// to update the visibility of the intermediate use so that it isn't linted
441 /// by `unreachable_pub`.
443 /// This isn't trivial as `path.def` has the `DefId` of the eventual target
444 /// of the use statement not of the next intermediate use statement.
446 /// To do this, consider the last two segments of the path to our intermediate
447 /// use statement. We expect the penultimate segment to be a module and the
448 /// last segment to be the name of the item we are exporting. We can then
449 /// look at the items contained in the module for the use statement with that
450 /// name and update that item's visibility.
452 /// FIXME: This solution won't work with glob imports and doesn't respect
453 /// namespaces. See <https://github.com/rust-lang/rust/pull/57922#discussion_r251234202>.
454 fn update_visibility_of_intermediate_use_statements(&mut self, segments: &[hir::PathSegment]) {
455 if let Some([module, segment]) = segments.rchunks_exact(2).next() {
456 if let Some(item) = module.def
457 .and_then(|def| def.mod_def_id())
458 .and_then(|def_id| self.tcx.hir().as_local_hir_id(def_id))
459 .map(|module_hir_id| self.tcx.hir().expect_item_by_hir_id(module_hir_id))
461 if let hir::ItemKind::Mod(m) = &item.node {
462 for item_id in m.item_ids.as_ref() {
463 let item = self.tcx.hir().expect_item(item_id.id);
464 let def_id = self.tcx.hir().local_def_id(item_id.id);
465 if !self.tcx.hygienic_eq(segment.ident, item.ident, def_id) { continue; }
466 if let hir::ItemKind::Use(..) = item.node {
467 self.update(item.id, Some(AccessLevel::Exported));
476 impl<'a, 'tcx> Visitor<'tcx> for EmbargoVisitor<'a, 'tcx> {
477 /// We want to visit items in the context of their containing
478 /// module and so forth, so supply a crate for doing a deep walk.
479 fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> {
480 NestedVisitorMap::All(&self.tcx.hir())
483 fn visit_item(&mut self, item: &'tcx hir::Item) {
484 let inherited_item_level = match item.node {
485 hir::ItemKind::Impl(..) =>
486 Option::<AccessLevel>::of_impl(item.id, self.tcx, &self.access_levels),
487 // Foreign modules inherit level from parents.
488 hir::ItemKind::ForeignMod(..) => self.prev_level,
489 // Other `pub` items inherit levels from parents.
490 hir::ItemKind::Const(..) | hir::ItemKind::Enum(..) | hir::ItemKind::ExternCrate(..) |
491 hir::ItemKind::GlobalAsm(..) | hir::ItemKind::Fn(..) | hir::ItemKind::Mod(..) |
492 hir::ItemKind::Static(..) | hir::ItemKind::Struct(..) |
493 hir::ItemKind::Trait(..) | hir::ItemKind::TraitAlias(..) |
494 hir::ItemKind::Existential(..) |
495 hir::ItemKind::Ty(..) | hir::ItemKind::Union(..) | hir::ItemKind::Use(..) => {
496 if item.vis.node.is_pub() { self.prev_level } else { None }
500 // Update level of the item itself.
501 let item_level = self.update(item.id, inherited_item_level);
503 // Update levels of nested things.
505 hir::ItemKind::Enum(ref def, _) => {
506 for variant in &def.variants {
507 let variant_level = self.update(variant.node.data.id(), item_level);
508 for field in variant.node.data.fields() {
509 self.update(field.id, variant_level);
513 hir::ItemKind::Impl(.., ref trait_ref, _, ref impl_item_refs) => {
514 for impl_item_ref in impl_item_refs {
515 if trait_ref.is_some() || impl_item_ref.vis.node.is_pub() {
516 self.update(impl_item_ref.id.node_id, item_level);
520 hir::ItemKind::Trait(.., ref trait_item_refs) => {
521 for trait_item_ref in trait_item_refs {
522 self.update(trait_item_ref.id.node_id, item_level);
525 hir::ItemKind::Struct(ref def, _) | hir::ItemKind::Union(ref def, _) => {
526 if !def.is_struct() {
527 self.update(def.id(), item_level);
529 for field in def.fields() {
530 if field.vis.node.is_pub() {
531 self.update(field.id, item_level);
535 hir::ItemKind::ForeignMod(ref foreign_mod) => {
536 for foreign_item in &foreign_mod.items {
537 if foreign_item.vis.node.is_pub() {
538 self.update(foreign_item.id, item_level);
542 hir::ItemKind::Existential(..) |
543 hir::ItemKind::Use(..) |
544 hir::ItemKind::Static(..) |
545 hir::ItemKind::Const(..) |
546 hir::ItemKind::GlobalAsm(..) |
547 hir::ItemKind::Ty(..) |
548 hir::ItemKind::Mod(..) |
549 hir::ItemKind::TraitAlias(..) |
550 hir::ItemKind::Fn(..) |
551 hir::ItemKind::ExternCrate(..) => {}
554 // Mark all items in interfaces of reachable items as reachable.
556 // The interface is empty.
557 hir::ItemKind::ExternCrate(..) => {}
558 // All nested items are checked by `visit_item`.
559 hir::ItemKind::Mod(..) => {}
560 // Re-exports are handled in `visit_mod`. However, in order to avoid looping over
561 // all of the items of a mod in `visit_mod` looking for use statements, we handle
562 // making sure that intermediate use statements have their visibilities updated here.
563 hir::ItemKind::Use(ref path, _) => {
564 if item_level.is_some() {
565 self.update_visibility_of_intermediate_use_statements(path.segments.as_ref());
568 // The interface is empty.
569 hir::ItemKind::GlobalAsm(..) => {}
570 hir::ItemKind::Existential(..) => {
571 // FIXME: This is some serious pessimization intended to workaround deficiencies
572 // in the reachability pass (`middle/reachable.rs`). Types are marked as link-time
573 // reachable if they are returned via `impl Trait`, even from private functions.
574 let exist_level = cmp::max(item_level, Some(AccessLevel::ReachableFromImplTrait));
575 self.reach(item.id, exist_level).generics().predicates().ty();
578 hir::ItemKind::Const(..) | hir::ItemKind::Static(..) |
579 hir::ItemKind::Fn(..) | hir::ItemKind::Ty(..) => {
580 if item_level.is_some() {
581 self.reach(item.id, item_level).generics().predicates().ty();
584 hir::ItemKind::Trait(.., ref trait_item_refs) => {
585 if item_level.is_some() {
586 self.reach(item.id, item_level).generics().predicates();
588 for trait_item_ref in trait_item_refs {
589 let mut reach = self.reach(trait_item_ref.id.node_id, item_level);
590 reach.generics().predicates();
592 if trait_item_ref.kind == AssociatedItemKind::Type &&
593 !trait_item_ref.defaultness.has_value() {
601 hir::ItemKind::TraitAlias(..) => {
602 if item_level.is_some() {
603 self.reach(item.id, item_level).generics().predicates();
606 // Visit everything except for private impl items.
607 hir::ItemKind::Impl(.., ref impl_item_refs) => {
608 if item_level.is_some() {
609 self.reach(item.id, item_level).generics().predicates().ty().trait_ref();
611 for impl_item_ref in impl_item_refs {
612 let impl_item_level = self.get(impl_item_ref.id.node_id);
613 if impl_item_level.is_some() {
614 self.reach(impl_item_ref.id.node_id, impl_item_level)
615 .generics().predicates().ty();
621 // Visit everything, but enum variants have their own levels.
622 hir::ItemKind::Enum(ref def, _) => {
623 if item_level.is_some() {
624 self.reach(item.id, item_level).generics().predicates();
626 for variant in &def.variants {
627 let variant_level = self.get(variant.node.data.id());
628 if variant_level.is_some() {
629 for field in variant.node.data.fields() {
630 self.reach(field.id, variant_level).ty();
632 // Corner case: if the variant is reachable, but its
633 // enum is not, make the enum reachable as well.
634 self.update(item.id, variant_level);
638 // Visit everything, but foreign items have their own levels.
639 hir::ItemKind::ForeignMod(ref foreign_mod) => {
640 for foreign_item in &foreign_mod.items {
641 let foreign_item_level = self.get(foreign_item.id);
642 if foreign_item_level.is_some() {
643 self.reach(foreign_item.id, foreign_item_level)
644 .generics().predicates().ty();
648 // Visit everything except for private fields.
649 hir::ItemKind::Struct(ref struct_def, _) |
650 hir::ItemKind::Union(ref struct_def, _) => {
651 if item_level.is_some() {
652 self.reach(item.id, item_level).generics().predicates();
653 for field in struct_def.fields() {
654 let field_level = self.get(field.id);
655 if field_level.is_some() {
656 self.reach(field.id, field_level).ty();
663 let orig_level = mem::replace(&mut self.prev_level, item_level);
664 intravisit::walk_item(self, item);
665 self.prev_level = orig_level;
668 fn visit_block(&mut self, b: &'tcx hir::Block) {
669 // Blocks can have public items, for example impls, but they always
670 // start as completely private regardless of publicity of a function,
671 // constant, type, field, etc., in which this block resides.
672 let orig_level = mem::replace(&mut self.prev_level, None);
673 intravisit::walk_block(self, b);
674 self.prev_level = orig_level;
677 fn visit_mod(&mut self, m: &'tcx hir::Mod, _sp: Span, id: hir::HirId) {
678 // This code is here instead of in visit_item so that the
679 // crate module gets processed as well.
680 if self.prev_level.is_some() {
681 let def_id = self.tcx.hir().local_def_id_from_hir_id(id);
682 if let Some(exports) = self.tcx.module_exports(def_id) {
683 for export in exports.iter() {
684 if export.vis == ty::Visibility::Public {
685 if let Some(def_id) = export.def.opt_def_id() {
686 if let Some(node_id) = self.tcx.hir().as_local_node_id(def_id) {
687 self.update(node_id, Some(AccessLevel::Exported));
695 intravisit::walk_mod(self, m, id);
698 fn visit_macro_def(&mut self, md: &'tcx hir::MacroDef) {
699 let node_id = self.tcx.hir().hir_to_node_id(md.hir_id);
702 self.update(node_id, Some(AccessLevel::Public));
706 let module_did = ty::DefIdTree::parent(
708 self.tcx.hir().local_def_id_from_hir_id(md.hir_id)
710 let mut module_id = self.tcx.hir().as_local_node_id(module_did).unwrap();
711 let level = if md.vis.node.is_pub() { self.get(module_id) } else { None };
712 let level = self.update(node_id, level);
718 let module = if module_id == ast::CRATE_NODE_ID {
719 &self.tcx.hir().krate().module
720 } else if let hir::ItemKind::Mod(ref module) =
721 self.tcx.hir().expect_item(module_id).node {
726 for id in &module.item_ids {
727 self.update(id.id, level);
729 let def_id = self.tcx.hir().local_def_id(module_id);
730 if let Some(exports) = self.tcx.module_exports(def_id) {
731 for export in exports.iter() {
732 if let Some(node_id) = self.tcx.hir().as_local_node_id(export.def.def_id()) {
733 self.update(node_id, level);
738 if module_id == ast::CRATE_NODE_ID {
741 module_id = self.tcx.hir().get_parent_node(module_id);
746 impl<'a, 'tcx> ReachEverythingInTheInterfaceVisitor<'_, 'a, 'tcx> {
747 fn generics(&mut self) -> &mut Self {
748 for param in &self.ev.tcx.generics_of(self.item_def_id).params {
750 GenericParamDefKind::Type { has_default, .. } => {
752 self.visit(self.ev.tcx.type_of(param.def_id));
755 GenericParamDefKind::Lifetime => {}
761 fn predicates(&mut self) -> &mut Self {
762 self.visit_predicates(self.ev.tcx.predicates_of(self.item_def_id));
766 fn ty(&mut self) -> &mut Self {
767 self.visit(self.ev.tcx.type_of(self.item_def_id));
771 fn trait_ref(&mut self) -> &mut Self {
772 if let Some(trait_ref) = self.ev.tcx.impl_trait_ref(self.item_def_id) {
773 self.visit_trait(trait_ref);
779 impl<'a, 'tcx> DefIdVisitor<'a, 'tcx> for ReachEverythingInTheInterfaceVisitor<'_, 'a, 'tcx> {
780 fn tcx(&self) -> TyCtxt<'a, 'tcx, 'tcx> { self.ev.tcx }
781 fn visit_def_id(&mut self, def_id: DefId, _kind: &str, _descr: &dyn fmt::Display) -> bool {
782 if let Some(node_id) = self.ev.tcx.hir().as_local_node_id(def_id) {
783 self.ev.update(node_id, self.access_level);
789 //////////////////////////////////////////////////////////////////////////////////////
790 /// Name privacy visitor, checks privacy and reports violations.
791 /// Most of name privacy checks are performed during the main resolution phase,
792 /// or later in type checking when field accesses and associated items are resolved.
793 /// This pass performs remaining checks for fields in struct expressions and patterns.
794 //////////////////////////////////////////////////////////////////////////////////////
796 struct NamePrivacyVisitor<'a, 'tcx: 'a> {
797 tcx: TyCtxt<'a, 'tcx, 'tcx>,
798 tables: &'a ty::TypeckTables<'tcx>,
799 current_item: ast::NodeId,
800 empty_tables: &'a ty::TypeckTables<'tcx>,
803 impl<'a, 'tcx> NamePrivacyVisitor<'a, 'tcx> {
804 // Checks that a field in a struct constructor (expression or pattern) is accessible.
805 fn check_field(&mut self,
806 use_ctxt: Span, // syntax context of the field name at the use site
807 span: Span, // span of the field pattern, e.g., `x: 0`
808 def: &'tcx ty::AdtDef, // definition of the struct or enum
809 field: &'tcx ty::FieldDef) { // definition of the field
810 let ident = Ident::new(keywords::Invalid.name(), use_ctxt);
811 let current_hir = self.tcx.hir().node_to_hir_id(self.current_item);
812 let def_id = self.tcx.adjust_ident(ident, def.did, current_hir).1;
813 if !def.is_enum() && !field.vis.is_accessible_from(def_id, self.tcx) {
814 struct_span_err!(self.tcx.sess, span, E0451, "field `{}` of {} `{}` is private",
815 field.ident, def.variant_descr(), self.tcx.item_path_str(def.did))
816 .span_label(span, format!("field `{}` is private", field.ident))
822 impl<'a, 'tcx> Visitor<'tcx> for NamePrivacyVisitor<'a, 'tcx> {
823 /// We want to visit items in the context of their containing
824 /// module and so forth, so supply a crate for doing a deep walk.
825 fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> {
826 NestedVisitorMap::All(&self.tcx.hir())
829 fn visit_mod(&mut self, _m: &'tcx hir::Mod, _s: Span, _n: hir::HirId) {
830 // Don't visit nested modules, since we run a separate visitor walk
831 // for each module in `privacy_access_levels`
834 fn visit_nested_body(&mut self, body: hir::BodyId) {
835 let orig_tables = mem::replace(&mut self.tables, self.tcx.body_tables(body));
836 let body = self.tcx.hir().body(body);
837 self.visit_body(body);
838 self.tables = orig_tables;
841 fn visit_item(&mut self, item: &'tcx hir::Item) {
842 let orig_current_item = mem::replace(&mut self.current_item, item.id);
844 mem::replace(&mut self.tables, item_tables(self.tcx, item.id, self.empty_tables));
845 intravisit::walk_item(self, item);
846 self.current_item = orig_current_item;
847 self.tables = orig_tables;
850 fn visit_trait_item(&mut self, ti: &'tcx hir::TraitItem) {
852 mem::replace(&mut self.tables, item_tables(self.tcx, ti.id, self.empty_tables));
853 intravisit::walk_trait_item(self, ti);
854 self.tables = orig_tables;
857 fn visit_impl_item(&mut self, ii: &'tcx hir::ImplItem) {
859 mem::replace(&mut self.tables, item_tables(self.tcx, ii.id, self.empty_tables));
860 intravisit::walk_impl_item(self, ii);
861 self.tables = orig_tables;
864 fn visit_expr(&mut self, expr: &'tcx hir::Expr) {
866 hir::ExprKind::Struct(ref qpath, ref fields, ref base) => {
867 let def = self.tables.qpath_def(qpath, expr.hir_id);
868 let adt = self.tables.expr_ty(expr).ty_adt_def().unwrap();
869 let variant = adt.variant_of_def(def);
870 if let Some(ref base) = *base {
871 // If the expression uses FRU we need to make sure all the unmentioned fields
872 // are checked for privacy (RFC 736). Rather than computing the set of
873 // unmentioned fields, just check them all.
874 for (vf_index, variant_field) in variant.fields.iter().enumerate() {
875 let field = fields.iter().find(|f| {
876 self.tcx.field_index(f.hir_id, self.tables) == vf_index
878 let (use_ctxt, span) = match field {
879 Some(field) => (field.ident.span, field.span),
880 None => (base.span, base.span),
882 self.check_field(use_ctxt, span, adt, variant_field);
885 for field in fields {
886 let use_ctxt = field.ident.span;
887 let index = self.tcx.field_index(field.hir_id, self.tables);
888 self.check_field(use_ctxt, field.span, adt, &variant.fields[index]);
895 intravisit::walk_expr(self, expr);
898 fn visit_pat(&mut self, pat: &'tcx hir::Pat) {
900 PatKind::Struct(ref qpath, ref fields, _) => {
901 let def = self.tables.qpath_def(qpath, pat.hir_id);
902 let adt = self.tables.pat_ty(pat).ty_adt_def().unwrap();
903 let variant = adt.variant_of_def(def);
904 for field in fields {
905 let use_ctxt = field.node.ident.span;
906 let index = self.tcx.field_index(field.node.hir_id, self.tables);
907 self.check_field(use_ctxt, field.span, adt, &variant.fields[index]);
913 intravisit::walk_pat(self, pat);
917 ////////////////////////////////////////////////////////////////////////////////////////////
918 /// Type privacy visitor, checks types for privacy and reports violations.
919 /// Both explicitly written types and inferred types of expressions and patters are checked.
920 /// Checks are performed on "semantic" types regardless of names and their hygiene.
921 ////////////////////////////////////////////////////////////////////////////////////////////
923 struct TypePrivacyVisitor<'a, 'tcx: 'a> {
924 tcx: TyCtxt<'a, 'tcx, 'tcx>,
925 tables: &'a ty::TypeckTables<'tcx>,
929 empty_tables: &'a ty::TypeckTables<'tcx>,
932 impl<'a, 'tcx> TypePrivacyVisitor<'a, 'tcx> {
933 fn item_is_accessible(&self, did: DefId) -> bool {
934 def_id_visibility(self.tcx, did).0.is_accessible_from(self.current_item, self.tcx)
937 // Take node-id of an expression or pattern and check its type for privacy.
938 fn check_expr_pat_type(&mut self, id: hir::HirId, span: Span) -> bool {
940 if self.visit(self.tables.node_type(id)) || self.visit(self.tables.node_substs(id)) {
943 if let Some(adjustments) = self.tables.adjustments().get(id) {
944 for adjustment in adjustments {
945 if self.visit(adjustment.target) {
953 fn check_def_id(&mut self, def_id: DefId, kind: &str, descr: &dyn fmt::Display) -> bool {
954 let is_error = !self.item_is_accessible(def_id);
956 self.tcx.sess.span_err(self.span, &format!("{} `{}` is private", kind, descr));
962 impl<'a, 'tcx> Visitor<'tcx> for TypePrivacyVisitor<'a, 'tcx> {
963 /// We want to visit items in the context of their containing
964 /// module and so forth, so supply a crate for doing a deep walk.
965 fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> {
966 NestedVisitorMap::All(&self.tcx.hir())
969 fn visit_mod(&mut self, _m: &'tcx hir::Mod, _s: Span, _n: hir::HirId) {
970 // Don't visit nested modules, since we run a separate visitor walk
971 // for each module in `privacy_access_levels`
974 fn visit_nested_body(&mut self, body: hir::BodyId) {
975 let orig_tables = mem::replace(&mut self.tables, self.tcx.body_tables(body));
976 let orig_in_body = mem::replace(&mut self.in_body, true);
977 let body = self.tcx.hir().body(body);
978 self.visit_body(body);
979 self.tables = orig_tables;
980 self.in_body = orig_in_body;
983 fn visit_ty(&mut self, hir_ty: &'tcx hir::Ty) {
984 self.span = hir_ty.span;
987 if self.visit(self.tables.node_type(hir_ty.hir_id)) {
991 // Types in signatures.
992 // FIXME: This is very ineffective. Ideally each HIR type should be converted
993 // into a semantic type only once and the result should be cached somehow.
994 if self.visit(rustc_typeck::hir_ty_to_ty(self.tcx, hir_ty)) {
999 intravisit::walk_ty(self, hir_ty);
1002 fn visit_trait_ref(&mut self, trait_ref: &'tcx hir::TraitRef) {
1003 self.span = trait_ref.path.span;
1005 // Avoid calling `hir_trait_to_predicates` in bodies, it will ICE.
1006 // The traits' privacy in bodies is already checked as a part of trait object types.
1007 let (principal, projections) =
1008 rustc_typeck::hir_trait_to_predicates(self.tcx, trait_ref);
1009 if self.visit_trait(*principal.skip_binder()) {
1012 for (poly_predicate, _) in projections {
1014 if self.visit(poly_predicate.skip_binder().ty) ||
1015 self.visit_trait(poly_predicate.skip_binder().projection_ty.trait_ref(tcx)) {
1021 intravisit::walk_trait_ref(self, trait_ref);
1024 // Check types of expressions
1025 fn visit_expr(&mut self, expr: &'tcx hir::Expr) {
1026 if self.check_expr_pat_type(expr.hir_id, expr.span) {
1027 // Do not check nested expressions if the error already happened.
1031 hir::ExprKind::Assign(.., ref rhs) | hir::ExprKind::Match(ref rhs, ..) => {
1032 // Do not report duplicate errors for `x = y` and `match x { ... }`.
1033 if self.check_expr_pat_type(rhs.hir_id, rhs.span) {
1037 hir::ExprKind::MethodCall(_, span, _) => {
1038 // Method calls have to be checked specially.
1040 if let Some(def) = self.tables.type_dependent_defs().get(expr.hir_id) {
1041 if self.visit(self.tcx.type_of(def.def_id())) {
1045 self.tcx.sess.delay_span_bug(expr.span,
1046 "no type-dependent def for method call");
1052 intravisit::walk_expr(self, expr);
1055 // Prohibit access to associated items with insufficient nominal visibility.
1057 // Additionally, until better reachability analysis for macros 2.0 is available,
1058 // we prohibit access to private statics from other crates, this allows to give
1059 // more code internal visibility at link time. (Access to private functions
1060 // is already prohibited by type privacy for function types.)
1061 fn visit_qpath(&mut self, qpath: &'tcx hir::QPath, id: hir::HirId, span: Span) {
1062 let def = match *qpath {
1063 hir::QPath::Resolved(_, ref path) => match path.def {
1064 Def::Method(..) | Def::AssociatedConst(..) |
1065 Def::AssociatedTy(..) | Def::AssociatedExistential(..) |
1066 Def::Static(..) => Some(path.def),
1069 hir::QPath::TypeRelative(..) => {
1070 self.tables.type_dependent_defs().get(id).cloned()
1073 if let Some(def) = def {
1074 let def_id = def.def_id();
1075 let is_local_static = if let Def::Static(..) = def { def_id.is_local() } else { false };
1076 if !self.item_is_accessible(def_id) && !is_local_static {
1077 let name = match *qpath {
1078 hir::QPath::Resolved(_, ref path) => path.to_string(),
1079 hir::QPath::TypeRelative(_, ref segment) => segment.ident.to_string(),
1081 let msg = format!("{} `{}` is private", def.kind_name(), name);
1082 self.tcx.sess.span_err(span, &msg);
1087 intravisit::walk_qpath(self, qpath, id, span);
1090 // Check types of patterns.
1091 fn visit_pat(&mut self, pattern: &'tcx hir::Pat) {
1092 if self.check_expr_pat_type(pattern.hir_id, pattern.span) {
1093 // Do not check nested patterns if the error already happened.
1097 intravisit::walk_pat(self, pattern);
1100 fn visit_local(&mut self, local: &'tcx hir::Local) {
1101 if let Some(ref init) = local.init {
1102 if self.check_expr_pat_type(init.hir_id, init.span) {
1103 // Do not report duplicate errors for `let x = y`.
1108 intravisit::walk_local(self, local);
1111 // Check types in item interfaces.
1112 fn visit_item(&mut self, item: &'tcx hir::Item) {
1113 let orig_current_item =
1114 mem::replace(&mut self.current_item, self.tcx.hir().local_def_id(item.id));
1115 let orig_in_body = mem::replace(&mut self.in_body, false);
1117 mem::replace(&mut self.tables, item_tables(self.tcx, item.id, self.empty_tables));
1118 intravisit::walk_item(self, item);
1119 self.tables = orig_tables;
1120 self.in_body = orig_in_body;
1121 self.current_item = orig_current_item;
1124 fn visit_trait_item(&mut self, ti: &'tcx hir::TraitItem) {
1126 mem::replace(&mut self.tables, item_tables(self.tcx, ti.id, self.empty_tables));
1127 intravisit::walk_trait_item(self, ti);
1128 self.tables = orig_tables;
1131 fn visit_impl_item(&mut self, ii: &'tcx hir::ImplItem) {
1133 mem::replace(&mut self.tables, item_tables(self.tcx, ii.id, self.empty_tables));
1134 intravisit::walk_impl_item(self, ii);
1135 self.tables = orig_tables;
1139 impl<'a, 'tcx> DefIdVisitor<'a, 'tcx> for TypePrivacyVisitor<'a, 'tcx> {
1140 fn tcx(&self) -> TyCtxt<'a, 'tcx, 'tcx> { self.tcx }
1141 fn visit_def_id(&mut self, def_id: DefId, kind: &str, descr: &dyn fmt::Display) -> bool {
1142 self.check_def_id(def_id, kind, descr)
1146 ///////////////////////////////////////////////////////////////////////////////
1147 /// Obsolete visitors for checking for private items in public interfaces.
1148 /// These visitors are supposed to be kept in frozen state and produce an
1149 /// "old error node set". For backward compatibility the new visitor reports
1150 /// warnings instead of hard errors when the erroneous node is not in this old set.
1151 ///////////////////////////////////////////////////////////////////////////////
1153 struct ObsoleteVisiblePrivateTypesVisitor<'a, 'tcx: 'a> {
1154 tcx: TyCtxt<'a, 'tcx, 'tcx>,
1155 access_levels: &'a AccessLevels,
1157 // Set of errors produced by this obsolete visitor.
1158 old_error_set: HirIdSet,
1161 struct ObsoleteCheckTypeForPrivatenessVisitor<'a, 'b: 'a, 'tcx: 'b> {
1162 inner: &'a ObsoleteVisiblePrivateTypesVisitor<'b, 'tcx>,
1163 /// Whether the type refers to private types.
1164 contains_private: bool,
1165 /// Whether we've recurred at all (i.e., if we're pointing at the
1166 /// first type on which `visit_ty` was called).
1167 at_outer_type: bool,
1168 /// Whether that first type is a public path.
1169 outer_type_is_public_path: bool,
1172 impl<'a, 'tcx> ObsoleteVisiblePrivateTypesVisitor<'a, 'tcx> {
1173 fn path_is_private_type(&self, path: &hir::Path) -> bool {
1174 let did = match path.def {
1175 Def::PrimTy(..) | Def::SelfTy(..) | Def::Err => return false,
1176 def => def.def_id(),
1179 // A path can only be private if:
1180 // it's in this crate...
1181 if let Some(node_id) = self.tcx.hir().as_local_node_id(did) {
1182 // .. and it corresponds to a private type in the AST (this returns
1183 // `None` for type parameters).
1184 match self.tcx.hir().find(node_id) {
1185 Some(Node::Item(ref item)) => !item.vis.node.is_pub(),
1186 Some(_) | None => false,
1193 fn trait_is_public(&self, trait_id: ast::NodeId) -> bool {
1194 // FIXME: this would preferably be using `exported_items`, but all
1195 // traits are exported currently (see `EmbargoVisitor.exported_trait`).
1196 self.access_levels.is_public(trait_id)
1199 fn check_generic_bound(&mut self, bound: &hir::GenericBound) {
1200 if let hir::GenericBound::Trait(ref trait_ref, _) = *bound {
1201 if self.path_is_private_type(&trait_ref.trait_ref.path) {
1202 self.old_error_set.insert(trait_ref.trait_ref.hir_ref_id);
1207 fn item_is_public(&self, id: &ast::NodeId, vis: &hir::Visibility) -> bool {
1208 self.access_levels.is_reachable(*id) || vis.node.is_pub()
1212 impl<'a, 'b, 'tcx, 'v> Visitor<'v> for ObsoleteCheckTypeForPrivatenessVisitor<'a, 'b, 'tcx> {
1213 fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'v> {
1214 NestedVisitorMap::None
1217 fn visit_ty(&mut self, ty: &hir::Ty) {
1218 if let hir::TyKind::Path(hir::QPath::Resolved(_, ref path)) = ty.node {
1219 if self.inner.path_is_private_type(path) {
1220 self.contains_private = true;
1221 // Found what we're looking for, so let's stop working.
1225 if let hir::TyKind::Path(_) = ty.node {
1226 if self.at_outer_type {
1227 self.outer_type_is_public_path = true;
1230 self.at_outer_type = false;
1231 intravisit::walk_ty(self, ty)
1234 // Don't want to recurse into `[, .. expr]`.
1235 fn visit_expr(&mut self, _: &hir::Expr) {}
1238 impl<'a, 'tcx> Visitor<'tcx> for ObsoleteVisiblePrivateTypesVisitor<'a, 'tcx> {
1239 /// We want to visit items in the context of their containing
1240 /// module and so forth, so supply a crate for doing a deep walk.
1241 fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> {
1242 NestedVisitorMap::All(&self.tcx.hir())
1245 fn visit_item(&mut self, item: &'tcx hir::Item) {
1247 // Contents of a private mod can be re-exported, so we need
1248 // to check internals.
1249 hir::ItemKind::Mod(_) => {}
1251 // An `extern {}` doesn't introduce a new privacy
1252 // namespace (the contents have their own privacies).
1253 hir::ItemKind::ForeignMod(_) => {}
1255 hir::ItemKind::Trait(.., ref bounds, _) => {
1256 if !self.trait_is_public(item.id) {
1260 for bound in bounds.iter() {
1261 self.check_generic_bound(bound)
1265 // Impls need some special handling to try to offer useful
1266 // error messages without (too many) false positives
1267 // (i.e., we could just return here to not check them at
1268 // all, or some worse estimation of whether an impl is
1269 // publicly visible).
1270 hir::ItemKind::Impl(.., ref g, ref trait_ref, ref self_, ref impl_item_refs) => {
1271 // `impl [... for] Private` is never visible.
1272 let self_contains_private;
1273 // `impl [... for] Public<...>`, but not `impl [... for]
1274 // Vec<Public>` or `(Public,)`, etc.
1275 let self_is_public_path;
1277 // Check the properties of the `Self` type:
1279 let mut visitor = ObsoleteCheckTypeForPrivatenessVisitor {
1281 contains_private: false,
1282 at_outer_type: true,
1283 outer_type_is_public_path: false,
1285 visitor.visit_ty(&self_);
1286 self_contains_private = visitor.contains_private;
1287 self_is_public_path = visitor.outer_type_is_public_path;
1290 // Miscellaneous info about the impl:
1292 // `true` iff this is `impl Private for ...`.
1293 let not_private_trait =
1294 trait_ref.as_ref().map_or(true, // no trait counts as public trait
1296 let did = tr.path.def.def_id();
1298 if let Some(node_id) = self.tcx.hir().as_local_node_id(did) {
1299 self.trait_is_public(node_id)
1301 true // external traits must be public
1305 // `true` iff this is a trait impl or at least one method is public.
1307 // `impl Public { $( fn ...() {} )* }` is not visible.
1309 // This is required over just using the methods' privacy
1310 // directly because we might have `impl<T: Foo<Private>> ...`,
1311 // and we shouldn't warn about the generics if all the methods
1312 // are private (because `T` won't be visible externally).
1313 let trait_or_some_public_method =
1314 trait_ref.is_some() ||
1315 impl_item_refs.iter()
1316 .any(|impl_item_ref| {
1317 let impl_item = self.tcx.hir().impl_item(impl_item_ref.id);
1318 match impl_item.node {
1319 hir::ImplItemKind::Const(..) |
1320 hir::ImplItemKind::Method(..) => {
1321 self.access_levels.is_reachable(impl_item.id)
1323 hir::ImplItemKind::Existential(..) |
1324 hir::ImplItemKind::Type(_) => false,
1328 if !self_contains_private &&
1329 not_private_trait &&
1330 trait_or_some_public_method {
1332 intravisit::walk_generics(self, g);
1336 for impl_item_ref in impl_item_refs {
1337 // This is where we choose whether to walk down
1338 // further into the impl to check its items. We
1339 // should only walk into public items so that we
1340 // don't erroneously report errors for private
1341 // types in private items.
1342 let impl_item = self.tcx.hir().impl_item(impl_item_ref.id);
1343 match impl_item.node {
1344 hir::ImplItemKind::Const(..) |
1345 hir::ImplItemKind::Method(..)
1346 if self.item_is_public(&impl_item.id, &impl_item.vis) =>
1348 intravisit::walk_impl_item(self, impl_item)
1350 hir::ImplItemKind::Type(..) => {
1351 intravisit::walk_impl_item(self, impl_item)
1358 // Any private types in a trait impl fall into three
1360 // 1. mentioned in the trait definition
1361 // 2. mentioned in the type params/generics
1362 // 3. mentioned in the associated types of the impl
1364 // Those in 1. can only occur if the trait is in
1365 // this crate and will've been warned about on the
1366 // trait definition (there's no need to warn twice
1367 // so we don't check the methods).
1369 // Those in 2. are warned via walk_generics and this
1371 intravisit::walk_path(self, &tr.path);
1373 // Those in 3. are warned with this call.
1374 for impl_item_ref in impl_item_refs {
1375 let impl_item = self.tcx.hir().impl_item(impl_item_ref.id);
1376 if let hir::ImplItemKind::Type(ref ty) = impl_item.node {
1382 } else if trait_ref.is_none() && self_is_public_path {
1383 // `impl Public<Private> { ... }`. Any public static
1384 // methods will be visible as `Public::foo`.
1385 let mut found_pub_static = false;
1386 for impl_item_ref in impl_item_refs {
1387 if self.item_is_public(&impl_item_ref.id.node_id, &impl_item_ref.vis) {
1388 let impl_item = self.tcx.hir().impl_item(impl_item_ref.id);
1389 match impl_item_ref.kind {
1390 AssociatedItemKind::Const => {
1391 found_pub_static = true;
1392 intravisit::walk_impl_item(self, impl_item);
1394 AssociatedItemKind::Method { has_self: false } => {
1395 found_pub_static = true;
1396 intravisit::walk_impl_item(self, impl_item);
1402 if found_pub_static {
1403 intravisit::walk_generics(self, g)
1409 // `type ... = ...;` can contain private types, because
1410 // we're introducing a new name.
1411 hir::ItemKind::Ty(..) => return,
1413 // Not at all public, so we don't care.
1414 _ if !self.item_is_public(&item.id, &item.vis) => {
1421 // We've carefully constructed it so that if we're here, then
1422 // any `visit_ty`'s will be called on things that are in
1423 // public signatures, i.e., things that we're interested in for
1425 intravisit::walk_item(self, item);
1428 fn visit_generics(&mut self, generics: &'tcx hir::Generics) {
1429 for param in &generics.params {
1430 for bound in ¶m.bounds {
1431 self.check_generic_bound(bound);
1434 for predicate in &generics.where_clause.predicates {
1436 hir::WherePredicate::BoundPredicate(bound_pred) => {
1437 for bound in bound_pred.bounds.iter() {
1438 self.check_generic_bound(bound)
1441 hir::WherePredicate::RegionPredicate(_) => {}
1442 hir::WherePredicate::EqPredicate(eq_pred) => {
1443 self.visit_ty(&eq_pred.rhs_ty);
1449 fn visit_foreign_item(&mut self, item: &'tcx hir::ForeignItem) {
1450 if self.access_levels.is_reachable(item.id) {
1451 intravisit::walk_foreign_item(self, item)
1455 fn visit_ty(&mut self, t: &'tcx hir::Ty) {
1456 if let hir::TyKind::Path(hir::QPath::Resolved(_, ref path)) = t.node {
1457 if self.path_is_private_type(path) {
1458 self.old_error_set.insert(t.hir_id);
1461 intravisit::walk_ty(self, t)
1464 fn visit_variant(&mut self,
1465 v: &'tcx hir::Variant,
1466 g: &'tcx hir::Generics,
1467 item_id: hir::HirId) {
1468 if self.access_levels.is_reachable(v.node.data.id()) {
1469 self.in_variant = true;
1470 intravisit::walk_variant(self, v, g, item_id);
1471 self.in_variant = false;
1475 fn visit_struct_field(&mut self, s: &'tcx hir::StructField) {
1476 if s.vis.node.is_pub() || self.in_variant {
1477 intravisit::walk_struct_field(self, s);
1481 // We don't need to introspect into these at all: an
1482 // expression/block context can't possibly contain exported things.
1483 // (Making them no-ops stops us from traversing the whole AST without
1484 // having to be super careful about our `walk_...` calls above.)
1485 fn visit_block(&mut self, _: &'tcx hir::Block) {}
1486 fn visit_expr(&mut self, _: &'tcx hir::Expr) {}
1489 ///////////////////////////////////////////////////////////////////////////////
1490 /// SearchInterfaceForPrivateItemsVisitor traverses an item's interface and
1491 /// finds any private components in it.
1492 /// PrivateItemsInPublicInterfacesVisitor ensures there are no private types
1493 /// and traits in public interfaces.
1494 ///////////////////////////////////////////////////////////////////////////////
1496 struct SearchInterfaceForPrivateItemsVisitor<'a, 'tcx: 'a> {
1497 tcx: TyCtxt<'a, 'tcx, 'tcx>,
1498 item_id: ast::NodeId,
1501 /// The visitor checks that each component type is at least this visible.
1502 required_visibility: ty::Visibility,
1503 has_pub_restricted: bool,
1504 has_old_errors: bool,
1506 private_crates: FxHashSet<CrateNum>
1509 impl<'a, 'tcx: 'a> SearchInterfaceForPrivateItemsVisitor<'a, 'tcx> {
1510 fn generics(&mut self) -> &mut Self {
1511 for param in &self.tcx.generics_of(self.item_def_id).params {
1513 GenericParamDefKind::Type { has_default, .. } => {
1515 self.visit(self.tcx.type_of(param.def_id));
1518 GenericParamDefKind::Lifetime => {}
1524 fn predicates(&mut self) -> &mut Self {
1525 // N.B., we use `explicit_predicates_of` and not `predicates_of`
1526 // because we don't want to report privacy errors due to where
1527 // clauses that the compiler inferred. We only want to
1528 // consider the ones that the user wrote. This is important
1529 // for the inferred outlives rules; see
1530 // `src/test/ui/rfc-2093-infer-outlives/privacy.rs`.
1531 self.visit_predicates(self.tcx.explicit_predicates_of(self.item_def_id));
1535 fn ty(&mut self) -> &mut Self {
1536 self.visit(self.tcx.type_of(self.item_def_id));
1540 fn check_def_id(&mut self, def_id: DefId, kind: &str, descr: &dyn fmt::Display) -> bool {
1541 if self.leaks_private_dep(def_id) {
1542 self.tcx.lint_node(lint::builtin::EXPORTED_PRIVATE_DEPENDENCIES,
1545 &format!("{} `{}` from private dependency '{}' in public \
1546 interface", kind, descr,
1547 self.tcx.crate_name(def_id.krate)));
1551 let node_id = match self.tcx.hir().as_local_node_id(def_id) {
1552 Some(node_id) => node_id,
1553 None => return false,
1556 let (vis, vis_span, vis_descr) = def_id_visibility(self.tcx, def_id);
1557 if !vis.is_at_least(self.required_visibility, self.tcx) {
1558 let msg = format!("{} {} `{}` in public interface", vis_descr, kind, descr);
1559 if self.has_pub_restricted || self.has_old_errors || self.in_assoc_ty {
1560 let mut err = if kind == "trait" {
1561 struct_span_err!(self.tcx.sess, self.span, E0445, "{}", msg)
1563 struct_span_err!(self.tcx.sess, self.span, E0446, "{}", msg)
1565 err.span_label(self.span, format!("can't leak {} {}", vis_descr, kind));
1566 err.span_label(vis_span, format!("`{}` declared as {}", descr, vis_descr));
1569 let err_code = if kind == "trait" { "E0445" } else { "E0446" };
1570 self.tcx.lint_node(lint::builtin::PRIVATE_IN_PUBLIC, node_id, self.span,
1571 &format!("{} (error {})", msg, err_code));
1579 /// An item is 'leaked' from a private dependency if all
1580 /// of the following are true:
1581 /// 1. It's contained within a public type
1582 /// 2. It comes from a private crate
1583 fn leaks_private_dep(&self, item_id: DefId) -> bool {
1584 let ret = self.required_visibility == ty::Visibility::Public &&
1585 self.private_crates.contains(&item_id.krate);
1587 log::debug!("leaks_private_dep(item_id={:?})={}", item_id, ret);
1592 impl<'a, 'tcx> DefIdVisitor<'a, 'tcx> for SearchInterfaceForPrivateItemsVisitor<'a, 'tcx> {
1593 fn tcx(&self) -> TyCtxt<'a, 'tcx, 'tcx> { self.tcx }
1594 fn visit_def_id(&mut self, def_id: DefId, kind: &str, descr: &dyn fmt::Display) -> bool {
1595 self.check_def_id(def_id, kind, descr)
1599 struct PrivateItemsInPublicInterfacesVisitor<'a, 'tcx: 'a> {
1600 tcx: TyCtxt<'a, 'tcx, 'tcx>,
1601 has_pub_restricted: bool,
1602 old_error_set: &'a HirIdSet,
1603 private_crates: FxHashSet<CrateNum>
1606 impl<'a, 'tcx> PrivateItemsInPublicInterfacesVisitor<'a, 'tcx> {
1607 fn check(&self, item_id: ast::NodeId, required_visibility: ty::Visibility)
1608 -> SearchInterfaceForPrivateItemsVisitor<'a, 'tcx> {
1609 let mut has_old_errors = false;
1611 // Slow path taken only if there any errors in the crate.
1612 for &id in self.old_error_set {
1613 // Walk up the nodes until we find `item_id` (or we hit a root).
1614 let mut id = self.tcx.hir().hir_to_node_id(id);
1617 has_old_errors = true;
1620 let parent = self.tcx.hir().get_parent_node(id);
1632 SearchInterfaceForPrivateItemsVisitor {
1635 item_def_id: self.tcx.hir().local_def_id(item_id),
1636 span: self.tcx.hir().span(item_id),
1637 required_visibility,
1638 has_pub_restricted: self.has_pub_restricted,
1641 private_crates: self.private_crates.clone()
1645 fn check_trait_or_impl_item(&self, node_id: ast::NodeId, assoc_item_kind: AssociatedItemKind,
1646 defaultness: hir::Defaultness, vis: ty::Visibility) {
1647 let mut check = self.check(node_id, vis);
1649 let (check_ty, is_assoc_ty) = match assoc_item_kind {
1650 AssociatedItemKind::Const | AssociatedItemKind::Method { .. } => (true, false),
1651 AssociatedItemKind::Type => (defaultness.has_value(), true),
1652 // `ty()` for existential types is the underlying type,
1653 // it's not a part of interface, so we skip it.
1654 AssociatedItemKind::Existential => (false, true),
1656 check.in_assoc_ty = is_assoc_ty;
1657 check.generics().predicates();
1664 impl<'a, 'tcx> Visitor<'tcx> for PrivateItemsInPublicInterfacesVisitor<'a, 'tcx> {
1665 fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> {
1666 NestedVisitorMap::OnlyBodies(&self.tcx.hir())
1669 fn visit_item(&mut self, item: &'tcx hir::Item) {
1671 let item_visibility = ty::Visibility::from_hir(&item.vis, item.id, tcx);
1674 // Crates are always public.
1675 hir::ItemKind::ExternCrate(..) => {}
1676 // All nested items are checked by `visit_item`.
1677 hir::ItemKind::Mod(..) => {}
1678 // Checked in resolve.
1679 hir::ItemKind::Use(..) => {}
1681 hir::ItemKind::GlobalAsm(..) => {}
1682 // Subitems of these items have inherited publicity.
1683 hir::ItemKind::Const(..) | hir::ItemKind::Static(..) |
1684 hir::ItemKind::Fn(..) | hir::ItemKind::Ty(..) => {
1685 self.check(item.id, item_visibility).generics().predicates().ty();
1687 hir::ItemKind::Existential(..) => {
1688 // `ty()` for existential types is the underlying type,
1689 // it's not a part of interface, so we skip it.
1690 self.check(item.id, item_visibility).generics().predicates();
1692 hir::ItemKind::Trait(.., ref trait_item_refs) => {
1693 self.check(item.id, item_visibility).generics().predicates();
1695 for trait_item_ref in trait_item_refs {
1696 self.check_trait_or_impl_item(trait_item_ref.id.node_id, trait_item_ref.kind,
1697 trait_item_ref.defaultness, item_visibility);
1700 hir::ItemKind::TraitAlias(..) => {
1701 self.check(item.id, item_visibility).generics().predicates();
1703 hir::ItemKind::Enum(ref def, _) => {
1704 self.check(item.id, item_visibility).generics().predicates();
1706 for variant in &def.variants {
1707 for field in variant.node.data.fields() {
1708 self.check(field.id, item_visibility).ty();
1712 // Subitems of foreign modules have their own publicity.
1713 hir::ItemKind::ForeignMod(ref foreign_mod) => {
1714 for foreign_item in &foreign_mod.items {
1715 let vis = ty::Visibility::from_hir(&foreign_item.vis, item.id, tcx);
1716 self.check(foreign_item.id, vis).generics().predicates().ty();
1719 // Subitems of structs and unions have their own publicity.
1720 hir::ItemKind::Struct(ref struct_def, _) |
1721 hir::ItemKind::Union(ref struct_def, _) => {
1722 self.check(item.id, item_visibility).generics().predicates();
1724 for field in struct_def.fields() {
1725 let field_visibility = ty::Visibility::from_hir(&field.vis, item.id, tcx);
1726 self.check(field.id, min(item_visibility, field_visibility, tcx)).ty();
1729 // An inherent impl is public when its type is public
1730 // Subitems of inherent impls have their own publicity.
1731 // A trait impl is public when both its type and its trait are public
1732 // Subitems of trait impls have inherited publicity.
1733 hir::ItemKind::Impl(.., ref trait_ref, _, ref impl_item_refs) => {
1734 let impl_vis = ty::Visibility::of_impl(item.id, tcx, &Default::default());
1735 self.check(item.id, impl_vis).generics().predicates();
1736 for impl_item_ref in impl_item_refs {
1737 let impl_item = tcx.hir().impl_item(impl_item_ref.id);
1738 let impl_item_vis = if trait_ref.is_none() {
1739 min(ty::Visibility::from_hir(&impl_item.vis, item.id, tcx), impl_vis, tcx)
1743 self.check_trait_or_impl_item(impl_item_ref.id.node_id, impl_item_ref.kind,
1744 impl_item_ref.defaultness, impl_item_vis);
1751 pub fn provide(providers: &mut Providers<'_>) {
1752 *providers = Providers {
1753 privacy_access_levels,
1759 pub fn check_crate<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>) -> Lrc<AccessLevels> {
1760 tcx.privacy_access_levels(LOCAL_CRATE)
1763 fn check_mod_privacy<'tcx>(tcx: TyCtxt<'_, 'tcx, 'tcx>, module_def_id: DefId) {
1764 let empty_tables = ty::TypeckTables::empty(None);
1767 // Check privacy of names not checked in previous compilation stages.
1768 let mut visitor = NamePrivacyVisitor {
1770 tables: &empty_tables,
1771 current_item: DUMMY_NODE_ID,
1772 empty_tables: &empty_tables,
1774 let (module, span, node_id) = tcx.hir().get_module(module_def_id);
1775 let hir_id = tcx.hir().node_to_hir_id(node_id);
1776 intravisit::walk_mod(&mut visitor, module, hir_id);
1778 // Check privacy of explicitly written types and traits as well as
1779 // inferred types of expressions and patterns.
1780 let mut visitor = TypePrivacyVisitor {
1782 tables: &empty_tables,
1783 current_item: module_def_id,
1786 empty_tables: &empty_tables,
1788 intravisit::walk_mod(&mut visitor, module, hir_id);
1791 fn privacy_access_levels<'tcx>(
1792 tcx: TyCtxt<'_, 'tcx, 'tcx>,
1794 ) -> Lrc<AccessLevels> {
1795 assert_eq!(krate, LOCAL_CRATE);
1797 let krate = tcx.hir().krate();
1799 for &module in krate.modules.keys() {
1800 tcx.ensure().check_mod_privacy(tcx.hir().local_def_id(module));
1803 let private_crates: FxHashSet<CrateNum> = tcx.sess.opts.extern_private.iter()
1805 tcx.crates().iter().find(|&&krate| &tcx.crate_name(krate) == c).cloned()
1809 // Build up a set of all exported items in the AST. This is a set of all
1810 // items which are reachable from external crates based on visibility.
1811 let mut visitor = EmbargoVisitor {
1813 access_levels: Default::default(),
1814 prev_level: Some(AccessLevel::Public),
1818 intravisit::walk_crate(&mut visitor, krate);
1819 if visitor.changed {
1820 visitor.changed = false;
1825 visitor.update(ast::CRATE_NODE_ID, Some(AccessLevel::Public));
1828 let mut visitor = ObsoleteVisiblePrivateTypesVisitor {
1830 access_levels: &visitor.access_levels,
1832 old_error_set: Default::default(),
1834 intravisit::walk_crate(&mut visitor, krate);
1837 let has_pub_restricted = {
1838 let mut pub_restricted_visitor = PubRestrictedVisitor {
1840 has_pub_restricted: false
1842 intravisit::walk_crate(&mut pub_restricted_visitor, krate);
1843 pub_restricted_visitor.has_pub_restricted
1846 // Check for private types and traits in public interfaces.
1847 let mut visitor = PrivateItemsInPublicInterfacesVisitor {
1850 old_error_set: &visitor.old_error_set,
1853 krate.visit_all_item_likes(&mut DeepVisitor::new(&mut visitor));
1856 Lrc::new(visitor.access_levels)
1859 __build_diagnostic_array! { librustc_privacy, DIAGNOSTICS }