1 // Copyright 2012-2014 The Rust Project Developers. See the COPYRIGHT
2 // file at the top-level directory of this distribution and at
3 // http://rust-lang.org/COPYRIGHT.
5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
8 // option. This file may not be copied, modified, or distributed
9 // except according to those terms.
11 #![crate_name = "rustc_privacy"]
12 #![unstable(feature = "rustc_private", issue = "27812")]
13 #![crate_type = "dylib"]
14 #![crate_type = "rlib"]
15 #![doc(html_logo_url = "https://www.rust-lang.org/logos/rust-logo-128x128-blk-v2.png",
16 html_favicon_url = "https://doc.rust-lang.org/favicon.ico",
17 html_root_url = "https://doc.rust-lang.org/nightly/")]
20 #![feature(rustc_diagnostic_macros)]
21 #![feature(rustc_private)]
22 #![feature(staged_api)]
25 #[macro_use] extern crate syntax;
26 extern crate syntax_pos;
28 use rustc::dep_graph::DepNode;
29 use rustc::hir::{self, PatKind};
30 use rustc::hir::def::{self, Def};
31 use rustc::hir::def_id::{CRATE_DEF_INDEX, DefId};
32 use rustc::hir::intravisit::{self, Visitor, NestedVisitorMap};
33 use rustc::hir::itemlikevisit::DeepVisitor;
34 use rustc::hir::pat_util::EnumerateAndAdjustIterator;
36 use rustc::middle::privacy::{AccessLevel, AccessLevels};
37 use rustc::ty::{self, TyCtxt, Ty, TypeFoldable};
38 use rustc::ty::fold::TypeVisitor;
39 use rustc::util::nodemap::NodeSet;
44 use std::mem::replace;
48 ////////////////////////////////////////////////////////////////////////////////
49 /// The embargo visitor, used to determine the exports of the ast
50 ////////////////////////////////////////////////////////////////////////////////
52 struct EmbargoVisitor<'a, 'tcx: 'a> {
53 tcx: TyCtxt<'a, 'tcx, 'tcx>,
54 export_map: &'a def::ExportMap,
56 // Accessibility levels for reachable nodes
57 access_levels: AccessLevels,
58 // Previous accessibility level, None means unreachable
59 prev_level: Option<AccessLevel>,
60 // Have something changed in the level map?
64 struct ReachEverythingInTheInterfaceVisitor<'b, 'a: 'b, 'tcx: 'a> {
66 ev: &'b mut EmbargoVisitor<'a, 'tcx>,
69 impl<'a, 'tcx> EmbargoVisitor<'a, 'tcx> {
70 fn item_ty_level(&self, item_def_id: DefId) -> Option<AccessLevel> {
71 let ty_def_id = match self.tcx.item_type(item_def_id).sty {
72 ty::TyAdt(adt, _) => adt.did,
73 ty::TyDynamic(ref obj, ..) if obj.principal().is_some() =>
74 obj.principal().unwrap().def_id(),
75 ty::TyProjection(ref proj) => proj.trait_ref.def_id,
76 _ => return Some(AccessLevel::Public)
78 if let Some(node_id) = self.tcx.hir.as_local_node_id(ty_def_id) {
81 Some(AccessLevel::Public)
85 fn impl_trait_level(&self, impl_def_id: DefId) -> Option<AccessLevel> {
86 if let Some(trait_ref) = self.tcx.impl_trait_ref(impl_def_id) {
87 if let Some(node_id) = self.tcx.hir.as_local_node_id(trait_ref.def_id) {
88 return self.get(node_id);
91 Some(AccessLevel::Public)
94 fn get(&self, id: ast::NodeId) -> Option<AccessLevel> {
95 self.access_levels.map.get(&id).cloned()
98 // Updates node level and returns the updated level
99 fn update(&mut self, id: ast::NodeId, level: Option<AccessLevel>) -> Option<AccessLevel> {
100 let old_level = self.get(id);
101 // Accessibility levels can only grow
102 if level > old_level {
103 self.access_levels.map.insert(id, level.unwrap());
111 fn reach<'b>(&'b mut self, item_id: ast::NodeId)
112 -> ReachEverythingInTheInterfaceVisitor<'b, 'a, 'tcx> {
113 ReachEverythingInTheInterfaceVisitor {
114 item_def_id: self.tcx.hir.local_def_id(item_id),
120 impl<'a, 'tcx> Visitor<'tcx> for EmbargoVisitor<'a, 'tcx> {
121 /// We want to visit items in the context of their containing
122 /// module and so forth, so supply a crate for doing a deep walk.
123 fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> {
124 NestedVisitorMap::All(&self.tcx.hir)
127 fn visit_item(&mut self, item: &'tcx hir::Item) {
128 let inherited_item_level = match item.node {
129 // Impls inherit level from their types and traits
130 hir::ItemImpl(..) => {
131 let def_id = self.tcx.hir.local_def_id(item.id);
132 cmp::min(self.item_ty_level(def_id), self.impl_trait_level(def_id))
134 hir::ItemDefaultImpl(..) => {
135 let def_id = self.tcx.hir.local_def_id(item.id);
136 self.impl_trait_level(def_id)
138 // Foreign mods inherit level from parents
139 hir::ItemForeignMod(..) => {
142 // Other `pub` items inherit levels from parents
144 if item.vis == hir::Public { self.prev_level } else { None }
148 // Update level of the item itself
149 let item_level = self.update(item.id, inherited_item_level);
151 // Update levels of nested things
153 hir::ItemEnum(ref def, _) => {
154 for variant in &def.variants {
155 let variant_level = self.update(variant.node.data.id(), item_level);
156 for field in variant.node.data.fields() {
157 self.update(field.id, variant_level);
161 hir::ItemImpl(.., None, _, ref impl_item_refs) => {
162 for impl_item_ref in impl_item_refs {
163 if impl_item_ref.vis == hir::Public {
164 self.update(impl_item_ref.id.node_id, item_level);
168 hir::ItemImpl(.., Some(_), _, ref impl_item_refs) => {
169 for impl_item_ref in impl_item_refs {
170 self.update(impl_item_ref.id.node_id, item_level);
173 hir::ItemTrait(.., ref trait_item_refs) => {
174 for trait_item_ref in trait_item_refs {
175 self.update(trait_item_ref.id.node_id, item_level);
178 hir::ItemStruct(ref def, _) | hir::ItemUnion(ref def, _) => {
179 if !def.is_struct() {
180 self.update(def.id(), item_level);
182 for field in def.fields() {
183 if field.vis == hir::Public {
184 self.update(field.id, item_level);
188 hir::ItemForeignMod(ref foreign_mod) => {
189 for foreign_item in &foreign_mod.items {
190 if foreign_item.vis == hir::Public {
191 self.update(foreign_item.id, item_level);
198 // Mark all items in interfaces of reachable items as reachable
200 // The interface is empty
201 hir::ItemExternCrate(..) => {}
202 // All nested items are checked by visit_item
203 hir::ItemMod(..) => {}
204 // Reexports are handled in visit_mod
205 hir::ItemUse(..) => {}
206 // The interface is empty
207 hir::ItemDefaultImpl(..) => {}
209 hir::ItemConst(..) | hir::ItemStatic(..) |
210 hir::ItemFn(..) | hir::ItemTy(..) => {
211 if item_level.is_some() {
212 self.reach(item.id).generics().predicates().item_type();
215 hir::ItemTrait(.., ref trait_item_refs) => {
216 if item_level.is_some() {
217 self.reach(item.id).generics().predicates();
219 for trait_item_ref in trait_item_refs {
220 let mut reach = self.reach(trait_item_ref.id.node_id);
221 reach.generics().predicates();
223 if trait_item_ref.kind == hir::AssociatedItemKind::Type &&
224 !trait_item_ref.defaultness.has_value() {
232 // Visit everything except for private impl items
233 hir::ItemImpl(.., ref trait_ref, _, ref impl_item_refs) => {
234 if item_level.is_some() {
235 self.reach(item.id).generics().predicates().impl_trait_ref();
237 for impl_item_ref in impl_item_refs {
238 let id = impl_item_ref.id.node_id;
239 if trait_ref.is_some() || self.get(id).is_some() {
240 self.reach(id).generics().predicates().item_type();
246 // Visit everything, but enum variants have their own levels
247 hir::ItemEnum(ref def, _) => {
248 if item_level.is_some() {
249 self.reach(item.id).generics().predicates();
251 for variant in &def.variants {
252 if self.get(variant.node.data.id()).is_some() {
253 for field in variant.node.data.fields() {
254 self.reach(field.id).item_type();
256 // Corner case: if the variant is reachable, but its
257 // enum is not, make the enum reachable as well.
258 self.update(item.id, Some(AccessLevel::Reachable));
262 // Visit everything, but foreign items have their own levels
263 hir::ItemForeignMod(ref foreign_mod) => {
264 for foreign_item in &foreign_mod.items {
265 if self.get(foreign_item.id).is_some() {
266 self.reach(foreign_item.id).generics().predicates().item_type();
270 // Visit everything except for private fields
271 hir::ItemStruct(ref struct_def, _) |
272 hir::ItemUnion(ref struct_def, _) => {
273 if item_level.is_some() {
274 self.reach(item.id).generics().predicates();
275 for field in struct_def.fields() {
276 if self.get(field.id).is_some() {
277 self.reach(field.id).item_type();
284 let orig_level = self.prev_level;
285 self.prev_level = item_level;
287 intravisit::walk_item(self, item);
289 self.prev_level = orig_level;
292 fn visit_block(&mut self, b: &'tcx hir::Block) {
293 let orig_level = replace(&mut self.prev_level, None);
295 // Blocks can have public items, for example impls, but they always
296 // start as completely private regardless of publicity of a function,
297 // constant, type, field, etc. in which this block resides
298 intravisit::walk_block(self, b);
300 self.prev_level = orig_level;
303 fn visit_mod(&mut self, m: &'tcx hir::Mod, _sp: Span, id: ast::NodeId) {
304 // This code is here instead of in visit_item so that the
305 // crate module gets processed as well.
306 if self.prev_level.is_some() {
307 if let Some(exports) = self.export_map.get(&id) {
308 for export in exports {
309 if let Some(node_id) = self.tcx.hir.as_local_node_id(export.def.def_id()) {
310 self.update(node_id, Some(AccessLevel::Exported));
316 intravisit::walk_mod(self, m, id);
319 fn visit_macro_def(&mut self, md: &'tcx hir::MacroDef) {
320 self.update(md.id, Some(AccessLevel::Public));
323 fn visit_ty(&mut self, ty: &'tcx hir::Ty) {
324 if let hir::TyImplTrait(..) = ty.node {
325 if self.get(ty.id).is_some() {
326 // Reach the (potentially private) type and the API being exposed.
327 self.reach(ty.id).item_type().predicates();
331 intravisit::walk_ty(self, ty);
335 impl<'b, 'a, 'tcx> ReachEverythingInTheInterfaceVisitor<'b, 'a, 'tcx> {
336 fn generics(&mut self) -> &mut Self {
337 for def in &self.ev.tcx.item_generics(self.item_def_id).types {
339 self.ev.tcx.item_type(def.def_id).visit_with(self);
345 fn predicates(&mut self) -> &mut Self {
346 self.ev.tcx.item_predicates(self.item_def_id).visit_with(self);
350 fn item_type(&mut self) -> &mut Self {
351 self.ev.tcx.item_type(self.item_def_id).visit_with(self);
355 fn impl_trait_ref(&mut self) -> &mut Self {
356 self.ev.tcx.impl_trait_ref(self.item_def_id).visit_with(self);
361 impl<'b, 'a, 'tcx> TypeVisitor<'tcx> for ReachEverythingInTheInterfaceVisitor<'b, 'a, 'tcx> {
362 fn visit_ty(&mut self, ty: Ty<'tcx>) -> bool {
363 let ty_def_id = match ty.sty {
364 ty::TyAdt(adt, _) => Some(adt.did),
365 ty::TyDynamic(ref obj, ..) => obj.principal().map(|p| p.def_id()),
366 ty::TyProjection(ref proj) => Some(proj.trait_ref.def_id),
367 ty::TyFnDef(def_id, ..) |
368 ty::TyAnon(def_id, _) => Some(def_id),
372 if let Some(def_id) = ty_def_id {
373 if let Some(node_id) = self.ev.tcx.hir.as_local_node_id(def_id) {
374 self.ev.update(node_id, Some(AccessLevel::Reachable));
378 ty.super_visit_with(self)
381 fn visit_trait_ref(&mut self, trait_ref: ty::TraitRef<'tcx>) -> bool {
382 if let Some(node_id) = self.ev.tcx.hir.as_local_node_id(trait_ref.def_id) {
383 let item = self.ev.tcx.hir.expect_item(node_id);
384 self.ev.update(item.id, Some(AccessLevel::Reachable));
387 trait_ref.super_visit_with(self)
391 ////////////////////////////////////////////////////////////////////////////////
392 /// The privacy visitor, where privacy checks take place (violations reported)
393 ////////////////////////////////////////////////////////////////////////////////
395 struct PrivacyVisitor<'a, 'tcx: 'a> {
396 tcx: TyCtxt<'a, 'tcx, 'tcx>,
399 tables: &'a ty::TypeckTables<'tcx>,
402 impl<'a, 'tcx> PrivacyVisitor<'a, 'tcx> {
403 fn item_is_accessible(&self, did: DefId) -> bool {
404 match self.tcx.hir.as_local_node_id(did) {
406 ty::Visibility::from_hir(&self.tcx.hir.expect_item(node_id).vis, node_id, self.tcx),
407 None => self.tcx.sess.cstore.visibility(did),
408 }.is_accessible_from(self.curitem, self.tcx)
411 // Checks that a field is in scope.
412 fn check_field(&mut self, span: Span, def: &'tcx ty::AdtDef, field: &'tcx ty::FieldDef) {
413 if !def.is_enum() && !field.vis.is_accessible_from(self.curitem, self.tcx) {
414 struct_span_err!(self.tcx.sess, span, E0451, "field `{}` of {} `{}` is private",
415 field.name, def.variant_descr(), self.tcx.item_path_str(def.did))
416 .span_label(span, &format!("field `{}` is private", field.name))
421 // Checks that a method is in scope.
422 fn check_method(&mut self, span: Span, method_def_id: DefId) {
423 match self.tcx.associated_item(method_def_id).container {
424 // Trait methods are always all public. The only controlling factor
425 // is whether the trait itself is accessible or not.
426 ty::TraitContainer(trait_def_id) if !self.item_is_accessible(trait_def_id) => {
427 let msg = format!("source trait `{}` is private",
428 self.tcx.item_path_str(trait_def_id));
429 self.tcx.sess.span_err(span, &msg);
436 impl<'a, 'tcx> Visitor<'tcx> for PrivacyVisitor<'a, 'tcx> {
437 /// We want to visit items in the context of their containing
438 /// module and so forth, so supply a crate for doing a deep walk.
439 fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> {
440 NestedVisitorMap::All(&self.tcx.hir)
443 fn visit_nested_body(&mut self, body: hir::BodyId) {
444 let old_tables = self.tables;
445 self.tables = self.tcx.body_tables(body);
446 let body = self.tcx.hir.body(body);
447 self.visit_body(body);
448 self.tables = old_tables;
451 fn visit_item(&mut self, item: &'tcx hir::Item) {
452 let orig_curitem = replace(&mut self.curitem, self.tcx.hir.local_def_id(item.id));
453 intravisit::walk_item(self, item);
454 self.curitem = orig_curitem;
457 fn visit_expr(&mut self, expr: &'tcx hir::Expr) {
459 hir::ExprMethodCall(..) => {
460 let method_call = ty::MethodCall::expr(expr.id);
461 let method = self.tables.method_map[&method_call];
462 self.check_method(expr.span, method.def_id);
464 hir::ExprStruct(ref qpath, ref expr_fields, _) => {
465 let def = self.tables.qpath_def(qpath, expr.id);
466 let adt = self.tables.expr_ty(expr).ty_adt_def().unwrap();
467 let variant = adt.variant_of_def(def);
468 // RFC 736: ensure all unmentioned fields are visible.
469 // Rather than computing the set of unmentioned fields
470 // (i.e. `all_fields - fields`), just check them all,
471 // unless the ADT is a union, then unmentioned fields
474 for expr_field in expr_fields {
475 self.check_field(expr.span, adt, variant.field_named(expr_field.name.node));
478 for field in &variant.fields {
479 let expr_field = expr_fields.iter().find(|f| f.name.node == field.name);
480 let span = if let Some(f) = expr_field { f.span } else { expr.span };
481 self.check_field(span, adt, field);
488 intravisit::walk_expr(self, expr);
491 fn visit_pat(&mut self, pattern: &'tcx hir::Pat) {
492 // Foreign functions do not have their patterns mapped in the def_map,
493 // and there's nothing really relevant there anyway, so don't bother
494 // checking privacy. If you can name the type then you can pass it to an
495 // external C function anyway.
496 if self.in_foreign { return }
499 PatKind::Struct(ref qpath, ref fields, _) => {
500 let def = self.tables.qpath_def(qpath, pattern.id);
501 let adt = self.tables.pat_ty(pattern).ty_adt_def().unwrap();
502 let variant = adt.variant_of_def(def);
503 for field in fields {
504 self.check_field(field.span, adt, variant.field_named(field.node.name));
507 PatKind::TupleStruct(_, ref fields, ddpos) => {
508 match self.tables.pat_ty(pattern).sty {
509 // enum fields have no privacy at this time
510 ty::TyAdt(def, _) if !def.is_enum() => {
511 let expected_len = def.struct_variant().fields.len();
512 for (i, field) in fields.iter().enumerate_and_adjust(expected_len, ddpos) {
513 if let PatKind::Wild = field.node {
516 self.check_field(field.span, def, &def.struct_variant().fields[i]);
525 intravisit::walk_pat(self, pattern);
528 fn visit_foreign_item(&mut self, fi: &'tcx hir::ForeignItem) {
529 self.in_foreign = true;
530 intravisit::walk_foreign_item(self, fi);
531 self.in_foreign = false;
535 ///////////////////////////////////////////////////////////////////////////////
536 /// Obsolete visitors for checking for private items in public interfaces.
537 /// These visitors are supposed to be kept in frozen state and produce an
538 /// "old error node set". For backward compatibility the new visitor reports
539 /// warnings instead of hard errors when the erroneous node is not in this old set.
540 ///////////////////////////////////////////////////////////////////////////////
542 struct ObsoleteVisiblePrivateTypesVisitor<'a, 'tcx: 'a> {
543 tcx: TyCtxt<'a, 'tcx, 'tcx>,
544 access_levels: &'a AccessLevels,
546 // set of errors produced by this obsolete visitor
547 old_error_set: NodeSet,
550 struct ObsoleteCheckTypeForPrivatenessVisitor<'a, 'b: 'a, 'tcx: 'b> {
551 inner: &'a ObsoleteVisiblePrivateTypesVisitor<'b, 'tcx>,
552 /// whether the type refers to private types.
553 contains_private: bool,
554 /// whether we've recurred at all (i.e. if we're pointing at the
555 /// first type on which visit_ty was called).
557 // whether that first type is a public path.
558 outer_type_is_public_path: bool,
561 impl<'a, 'tcx> ObsoleteVisiblePrivateTypesVisitor<'a, 'tcx> {
562 fn path_is_private_type(&self, path: &hir::Path) -> bool {
563 let did = match path.def {
564 Def::PrimTy(..) | Def::SelfTy(..) => return false,
568 // A path can only be private if:
569 // it's in this crate...
570 if let Some(node_id) = self.tcx.hir.as_local_node_id(did) {
571 // .. and it corresponds to a private type in the AST (this returns
572 // None for type parameters)
573 match self.tcx.hir.find(node_id) {
574 Some(hir::map::NodeItem(ref item)) => item.vis != hir::Public,
575 Some(_) | None => false,
582 fn trait_is_public(&self, trait_id: ast::NodeId) -> bool {
583 // FIXME: this would preferably be using `exported_items`, but all
584 // traits are exported currently (see `EmbargoVisitor.exported_trait`)
585 self.access_levels.is_public(trait_id)
588 fn check_ty_param_bound(&mut self,
589 ty_param_bound: &hir::TyParamBound) {
590 if let hir::TraitTyParamBound(ref trait_ref, _) = *ty_param_bound {
591 if self.path_is_private_type(&trait_ref.trait_ref.path) {
592 self.old_error_set.insert(trait_ref.trait_ref.ref_id);
597 fn item_is_public(&self, id: &ast::NodeId, vis: &hir::Visibility) -> bool {
598 self.access_levels.is_reachable(*id) || *vis == hir::Public
602 impl<'a, 'b, 'tcx, 'v> Visitor<'v> for ObsoleteCheckTypeForPrivatenessVisitor<'a, 'b, 'tcx> {
603 fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'v> {
604 NestedVisitorMap::None
607 fn visit_ty(&mut self, ty: &hir::Ty) {
608 if let hir::TyPath(hir::QPath::Resolved(_, ref path)) = ty.node {
609 if self.inner.path_is_private_type(path) {
610 self.contains_private = true;
611 // found what we're looking for so let's stop
616 if let hir::TyPath(_) = ty.node {
617 if self.at_outer_type {
618 self.outer_type_is_public_path = true;
621 self.at_outer_type = false;
622 intravisit::walk_ty(self, ty)
625 // don't want to recurse into [, .. expr]
626 fn visit_expr(&mut self, _: &hir::Expr) {}
629 impl<'a, 'tcx> Visitor<'tcx> for ObsoleteVisiblePrivateTypesVisitor<'a, 'tcx> {
630 /// We want to visit items in the context of their containing
631 /// module and so forth, so supply a crate for doing a deep walk.
632 fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> {
633 NestedVisitorMap::All(&self.tcx.hir)
636 fn visit_item(&mut self, item: &'tcx hir::Item) {
638 // contents of a private mod can be reexported, so we need
639 // to check internals.
640 hir::ItemMod(_) => {}
642 // An `extern {}` doesn't introduce a new privacy
643 // namespace (the contents have their own privacies).
644 hir::ItemForeignMod(_) => {}
646 hir::ItemTrait(.., ref bounds, _) => {
647 if !self.trait_is_public(item.id) {
651 for bound in bounds.iter() {
652 self.check_ty_param_bound(bound)
656 // impls need some special handling to try to offer useful
657 // error messages without (too many) false positives
658 // (i.e. we could just return here to not check them at
659 // all, or some worse estimation of whether an impl is
660 // publicly visible).
661 hir::ItemImpl(.., ref g, ref trait_ref, ref self_, ref impl_item_refs) => {
662 // `impl [... for] Private` is never visible.
663 let self_contains_private;
664 // impl [... for] Public<...>, but not `impl [... for]
665 // Vec<Public>` or `(Public,)` etc.
666 let self_is_public_path;
668 // check the properties of the Self type:
670 let mut visitor = ObsoleteCheckTypeForPrivatenessVisitor {
672 contains_private: false,
674 outer_type_is_public_path: false,
676 visitor.visit_ty(&self_);
677 self_contains_private = visitor.contains_private;
678 self_is_public_path = visitor.outer_type_is_public_path;
681 // miscellaneous info about the impl
683 // `true` iff this is `impl Private for ...`.
684 let not_private_trait =
685 trait_ref.as_ref().map_or(true, // no trait counts as public trait
687 let did = tr.path.def.def_id();
689 if let Some(node_id) = self.tcx.hir.as_local_node_id(did) {
690 self.trait_is_public(node_id)
692 true // external traits must be public
696 // `true` iff this is a trait impl or at least one method is public.
698 // `impl Public { $( fn ...() {} )* }` is not visible.
700 // This is required over just using the methods' privacy
701 // directly because we might have `impl<T: Foo<Private>> ...`,
702 // and we shouldn't warn about the generics if all the methods
703 // are private (because `T` won't be visible externally).
704 let trait_or_some_public_method =
705 trait_ref.is_some() ||
706 impl_item_refs.iter()
707 .any(|impl_item_ref| {
708 let impl_item = self.tcx.hir.impl_item(impl_item_ref.id);
709 match impl_item.node {
710 hir::ImplItemKind::Const(..) |
711 hir::ImplItemKind::Method(..) => {
712 self.access_levels.is_reachable(impl_item.id)
714 hir::ImplItemKind::Type(_) => false,
718 if !self_contains_private &&
720 trait_or_some_public_method {
722 intravisit::walk_generics(self, g);
726 for impl_item_ref in impl_item_refs {
727 // This is where we choose whether to walk down
728 // further into the impl to check its items. We
729 // should only walk into public items so that we
730 // don't erroneously report errors for private
731 // types in private items.
732 let impl_item = self.tcx.hir.impl_item(impl_item_ref.id);
733 match impl_item.node {
734 hir::ImplItemKind::Const(..) |
735 hir::ImplItemKind::Method(..)
736 if self.item_is_public(&impl_item.id, &impl_item.vis) =>
738 intravisit::walk_impl_item(self, impl_item)
740 hir::ImplItemKind::Type(..) => {
741 intravisit::walk_impl_item(self, impl_item)
748 // Any private types in a trait impl fall into three
750 // 1. mentioned in the trait definition
751 // 2. mentioned in the type params/generics
752 // 3. mentioned in the associated types of the impl
754 // Those in 1. can only occur if the trait is in
755 // this crate and will've been warned about on the
756 // trait definition (there's no need to warn twice
757 // so we don't check the methods).
759 // Those in 2. are warned via walk_generics and this
761 intravisit::walk_path(self, &tr.path);
763 // Those in 3. are warned with this call.
764 for impl_item_ref in impl_item_refs {
765 let impl_item = self.tcx.hir.impl_item(impl_item_ref.id);
766 if let hir::ImplItemKind::Type(ref ty) = impl_item.node {
772 } else if trait_ref.is_none() && self_is_public_path {
773 // impl Public<Private> { ... }. Any public static
774 // methods will be visible as `Public::foo`.
775 let mut found_pub_static = false;
776 for impl_item_ref in impl_item_refs {
777 if self.item_is_public(&impl_item_ref.id.node_id, &impl_item_ref.vis) {
778 let impl_item = self.tcx.hir.impl_item(impl_item_ref.id);
779 match impl_item_ref.kind {
780 hir::AssociatedItemKind::Const => {
781 found_pub_static = true;
782 intravisit::walk_impl_item(self, impl_item);
784 hir::AssociatedItemKind::Method { has_self: false } => {
785 found_pub_static = true;
786 intravisit::walk_impl_item(self, impl_item);
792 if found_pub_static {
793 intravisit::walk_generics(self, g)
799 // `type ... = ...;` can contain private types, because
800 // we're introducing a new name.
801 hir::ItemTy(..) => return,
803 // not at all public, so we don't care
804 _ if !self.item_is_public(&item.id, &item.vis) => {
811 // We've carefully constructed it so that if we're here, then
812 // any `visit_ty`'s will be called on things that are in
813 // public signatures, i.e. things that we're interested in for
815 intravisit::walk_item(self, item);
818 fn visit_generics(&mut self, generics: &'tcx hir::Generics) {
819 for ty_param in generics.ty_params.iter() {
820 for bound in ty_param.bounds.iter() {
821 self.check_ty_param_bound(bound)
824 for predicate in &generics.where_clause.predicates {
826 &hir::WherePredicate::BoundPredicate(ref bound_pred) => {
827 for bound in bound_pred.bounds.iter() {
828 self.check_ty_param_bound(bound)
831 &hir::WherePredicate::RegionPredicate(_) => {}
832 &hir::WherePredicate::EqPredicate(ref eq_pred) => {
833 self.visit_ty(&eq_pred.rhs_ty);
839 fn visit_foreign_item(&mut self, item: &'tcx hir::ForeignItem) {
840 if self.access_levels.is_reachable(item.id) {
841 intravisit::walk_foreign_item(self, item)
845 fn visit_ty(&mut self, t: &'tcx hir::Ty) {
846 if let hir::TyPath(hir::QPath::Resolved(_, ref path)) = t.node {
847 if self.path_is_private_type(path) {
848 self.old_error_set.insert(t.id);
851 intravisit::walk_ty(self, t)
854 fn visit_variant(&mut self,
855 v: &'tcx hir::Variant,
856 g: &'tcx hir::Generics,
857 item_id: ast::NodeId) {
858 if self.access_levels.is_reachable(v.node.data.id()) {
859 self.in_variant = true;
860 intravisit::walk_variant(self, v, g, item_id);
861 self.in_variant = false;
865 fn visit_struct_field(&mut self, s: &'tcx hir::StructField) {
866 if s.vis == hir::Public || self.in_variant {
867 intravisit::walk_struct_field(self, s);
871 // we don't need to introspect into these at all: an
872 // expression/block context can't possibly contain exported things.
873 // (Making them no-ops stops us from traversing the whole AST without
874 // having to be super careful about our `walk_...` calls above.)
875 fn visit_block(&mut self, _: &'tcx hir::Block) {}
876 fn visit_expr(&mut self, _: &'tcx hir::Expr) {}
879 ///////////////////////////////////////////////////////////////////////////////
880 /// SearchInterfaceForPrivateItemsVisitor traverses an item's interface and
881 /// finds any private components in it.
882 /// PrivateItemsInPublicInterfacesVisitor ensures there are no private types
883 /// and traits in public interfaces.
884 ///////////////////////////////////////////////////////////////////////////////
886 struct SearchInterfaceForPrivateItemsVisitor<'a, 'tcx: 'a> {
887 tcx: TyCtxt<'a, 'tcx, 'tcx>,
890 /// The visitor checks that each component type is at least this visible
891 required_visibility: ty::Visibility,
892 /// The visibility of the least visible component that has been visited
893 min_visibility: ty::Visibility,
894 has_old_errors: bool,
897 impl<'a, 'tcx: 'a> SearchInterfaceForPrivateItemsVisitor<'a, 'tcx> {
898 fn generics(&mut self) -> &mut Self {
899 for def in &self.tcx.item_generics(self.item_def_id).types {
901 self.tcx.item_type(def.def_id).visit_with(self);
907 fn predicates(&mut self) -> &mut Self {
908 self.tcx.item_predicates(self.item_def_id).visit_with(self);
912 fn item_type(&mut self) -> &mut Self {
913 self.tcx.item_type(self.item_def_id).visit_with(self);
917 fn impl_trait_ref(&mut self) -> &mut Self {
918 self.tcx.impl_trait_ref(self.item_def_id).visit_with(self);
923 impl<'a, 'tcx: 'a> TypeVisitor<'tcx> for SearchInterfaceForPrivateItemsVisitor<'a, 'tcx> {
924 fn visit_ty(&mut self, ty: Ty<'tcx>) -> bool {
925 let ty_def_id = match ty.sty {
926 ty::TyAdt(adt, _) => Some(adt.did),
927 ty::TyDynamic(ref obj, ..) => obj.principal().map(|p| p.def_id()),
928 ty::TyProjection(ref proj) => {
929 if self.required_visibility == ty::Visibility::Invisible {
930 // Conservatively approximate the whole type alias as public without
931 // recursing into its components when determining impl publicity.
932 // For example, `impl <Type as Trait>::Alias {...}` may be a public impl
933 // even if both `Type` and `Trait` are private.
934 // Ideally, associated types should be substituted in the same way as
935 // free type aliases, but this isn't done yet.
939 Some(proj.trait_ref.def_id)
944 if let Some(def_id) = ty_def_id {
945 // Non-local means public (private items can't leave their crate, modulo bugs)
946 if let Some(node_id) = self.tcx.hir.as_local_node_id(def_id) {
947 let item = self.tcx.hir.expect_item(node_id);
948 let vis = ty::Visibility::from_hir(&item.vis, node_id, self.tcx);
950 if !vis.is_at_least(self.min_visibility, self.tcx) {
951 self.min_visibility = vis;
953 if !vis.is_at_least(self.required_visibility, self.tcx) {
954 if self.tcx.sess.features.borrow().pub_restricted || self.has_old_errors {
955 let mut err = struct_span_err!(self.tcx.sess, self.span, E0446,
956 "private type `{}` in public interface", ty);
957 err.span_label(self.span, &format!("can't leak private type"));
960 self.tcx.sess.add_lint(lint::builtin::PRIVATE_IN_PUBLIC,
963 format!("private type `{}` in public \
964 interface (error E0446)", ty));
970 if let ty::TyProjection(ref proj) = ty.sty {
971 // Avoid calling `visit_trait_ref` below on the trait,
972 // as we have already checked the trait itself above.
973 proj.trait_ref.super_visit_with(self)
975 ty.super_visit_with(self)
979 fn visit_trait_ref(&mut self, trait_ref: ty::TraitRef<'tcx>) -> bool {
980 // Non-local means public (private items can't leave their crate, modulo bugs)
981 if let Some(node_id) = self.tcx.hir.as_local_node_id(trait_ref.def_id) {
982 let item = self.tcx.hir.expect_item(node_id);
983 let vis = ty::Visibility::from_hir(&item.vis, node_id, self.tcx);
985 if !vis.is_at_least(self.min_visibility, self.tcx) {
986 self.min_visibility = vis;
988 if !vis.is_at_least(self.required_visibility, self.tcx) {
989 if self.tcx.sess.features.borrow().pub_restricted || self.has_old_errors {
990 struct_span_err!(self.tcx.sess, self.span, E0445,
991 "private trait `{}` in public interface", trait_ref)
992 .span_label(self.span, &format!(
993 "private trait can't be public"))
996 self.tcx.sess.add_lint(lint::builtin::PRIVATE_IN_PUBLIC,
999 format!("private trait `{}` in public \
1000 interface (error E0445)", trait_ref));
1005 trait_ref.super_visit_with(self)
1009 struct PrivateItemsInPublicInterfacesVisitor<'a, 'tcx: 'a> {
1010 tcx: TyCtxt<'a, 'tcx, 'tcx>,
1011 old_error_set: &'a NodeSet,
1012 inner_visibility: ty::Visibility,
1015 impl<'a, 'tcx> PrivateItemsInPublicInterfacesVisitor<'a, 'tcx> {
1016 fn check(&self, item_id: ast::NodeId, required_visibility: ty::Visibility)
1017 -> SearchInterfaceForPrivateItemsVisitor<'a, 'tcx> {
1018 let mut has_old_errors = false;
1020 // Slow path taken only if there any errors in the crate.
1021 for &id in self.old_error_set {
1022 // Walk up the nodes until we find `item_id` (or we hit a root).
1026 has_old_errors = true;
1029 let parent = self.tcx.hir.get_parent_node(id);
1041 SearchInterfaceForPrivateItemsVisitor {
1043 item_def_id: self.tcx.hir.local_def_id(item_id),
1044 span: self.tcx.hir.span(item_id),
1045 min_visibility: ty::Visibility::Public,
1046 required_visibility: required_visibility,
1047 has_old_errors: has_old_errors,
1052 impl<'a, 'tcx> Visitor<'tcx> for PrivateItemsInPublicInterfacesVisitor<'a, 'tcx> {
1053 fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> {
1054 NestedVisitorMap::OnlyBodies(&self.tcx.hir)
1057 fn visit_item(&mut self, item: &'tcx hir::Item) {
1059 let min = |vis1: ty::Visibility, vis2| {
1060 if vis1.is_at_least(vis2, tcx) { vis2 } else { vis1 }
1063 let item_visibility = ty::Visibility::from_hir(&item.vis, item.id, tcx);
1066 // Crates are always public
1067 hir::ItemExternCrate(..) => {}
1068 // All nested items are checked by visit_item
1069 hir::ItemMod(..) => {}
1070 // Checked in resolve
1071 hir::ItemUse(..) => {}
1072 // Subitems of these items have inherited publicity
1073 hir::ItemConst(..) | hir::ItemStatic(..) | hir::ItemFn(..) |
1074 hir::ItemTy(..) => {
1075 self.check(item.id, item_visibility).generics().predicates().item_type();
1077 // Recurse for e.g. `impl Trait` (see `visit_ty`).
1078 self.inner_visibility = item_visibility;
1079 intravisit::walk_item(self, item);
1081 hir::ItemTrait(.., ref trait_item_refs) => {
1082 self.check(item.id, item_visibility).generics().predicates();
1084 for trait_item_ref in trait_item_refs {
1085 let mut check = self.check(trait_item_ref.id.node_id, item_visibility);
1086 check.generics().predicates();
1088 if trait_item_ref.kind == hir::AssociatedItemKind::Type &&
1089 !trait_item_ref.defaultness.has_value() {
1090 // No type to visit.
1096 hir::ItemEnum(ref def, _) => {
1097 self.check(item.id, item_visibility).generics().predicates();
1099 for variant in &def.variants {
1100 for field in variant.node.data.fields() {
1101 self.check(field.id, item_visibility).item_type();
1105 // Subitems of foreign modules have their own publicity
1106 hir::ItemForeignMod(ref foreign_mod) => {
1107 for foreign_item in &foreign_mod.items {
1108 let vis = ty::Visibility::from_hir(&foreign_item.vis, item.id, tcx);
1109 self.check(foreign_item.id, vis).generics().predicates().item_type();
1112 // Subitems of structs and unions have their own publicity
1113 hir::ItemStruct(ref struct_def, _) |
1114 hir::ItemUnion(ref struct_def, _) => {
1115 self.check(item.id, item_visibility).generics().predicates();
1117 for field in struct_def.fields() {
1118 let field_visibility = ty::Visibility::from_hir(&field.vis, item.id, tcx);
1119 self.check(field.id, min(item_visibility, field_visibility)).item_type();
1122 // The interface is empty
1123 hir::ItemDefaultImpl(..) => {}
1124 // An inherent impl is public when its type is public
1125 // Subitems of inherent impls have their own publicity
1126 hir::ItemImpl(.., None, _, ref impl_item_refs) => {
1128 self.check(item.id, ty::Visibility::Invisible).item_type().min_visibility;
1129 self.check(item.id, ty_vis).generics().predicates();
1131 for impl_item_ref in impl_item_refs {
1132 let impl_item = self.tcx.hir.impl_item(impl_item_ref.id);
1134 ty::Visibility::from_hir(&impl_item.vis, item.id, tcx);
1135 self.check(impl_item.id, min(impl_item_vis, ty_vis))
1136 .generics().predicates().item_type();
1138 // Recurse for e.g. `impl Trait` (see `visit_ty`).
1139 self.inner_visibility = impl_item_vis;
1140 intravisit::walk_impl_item(self, impl_item);
1143 // A trait impl is public when both its type and its trait are public
1144 // Subitems of trait impls have inherited publicity
1145 hir::ItemImpl(.., Some(_), _, ref impl_item_refs) => {
1146 let vis = self.check(item.id, ty::Visibility::Invisible)
1147 .item_type().impl_trait_ref().min_visibility;
1148 self.check(item.id, vis).generics().predicates();
1149 for impl_item_ref in impl_item_refs {
1150 let impl_item = self.tcx.hir.impl_item(impl_item_ref.id);
1151 self.check(impl_item.id, vis).generics().predicates().item_type();
1153 // Recurse for e.g. `impl Trait` (see `visit_ty`).
1154 self.inner_visibility = vis;
1155 intravisit::walk_impl_item(self, impl_item);
1161 fn visit_impl_item(&mut self, _impl_item: &'tcx hir::ImplItem) {
1162 // handled in `visit_item` above
1165 fn visit_ty(&mut self, ty: &'tcx hir::Ty) {
1166 if let hir::TyImplTrait(..) = ty.node {
1167 // Check the traits being exposed, as they're separate,
1168 // e.g. `impl Iterator<Item=T>` has two predicates,
1169 // `X: Iterator` and `<X as Iterator>::Item == T`,
1170 // where `X` is the `impl Iterator<Item=T>` itself,
1171 // stored in `item_predicates`, not in the `Ty` itself.
1172 self.check(ty.id, self.inner_visibility).predicates();
1175 intravisit::walk_ty(self, ty);
1178 // Don't recurse into expressions in array sizes or const initializers
1179 fn visit_expr(&mut self, _: &'tcx hir::Expr) {}
1180 // Don't recurse into patterns in function arguments
1181 fn visit_pat(&mut self, _: &'tcx hir::Pat) {}
1184 pub fn check_crate<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
1185 export_map: &def::ExportMap)
1187 let _task = tcx.dep_graph.in_task(DepNode::Privacy);
1189 let krate = tcx.hir.krate();
1191 // Use the parent map to check the privacy of everything
1192 let mut visitor = PrivacyVisitor {
1193 curitem: DefId::local(CRATE_DEF_INDEX),
1196 tables: &ty::TypeckTables::empty(),
1198 intravisit::walk_crate(&mut visitor, krate);
1200 tcx.sess.abort_if_errors();
1202 // Build up a set of all exported items in the AST. This is a set of all
1203 // items which are reachable from external crates based on visibility.
1204 let mut visitor = EmbargoVisitor {
1206 export_map: export_map,
1207 access_levels: Default::default(),
1208 prev_level: Some(AccessLevel::Public),
1212 intravisit::walk_crate(&mut visitor, krate);
1213 if visitor.changed {
1214 visitor.changed = false;
1219 visitor.update(ast::CRATE_NODE_ID, Some(AccessLevel::Public));
1222 let mut visitor = ObsoleteVisiblePrivateTypesVisitor {
1224 access_levels: &visitor.access_levels,
1226 old_error_set: NodeSet(),
1228 intravisit::walk_crate(&mut visitor, krate);
1230 // Check for private types and traits in public interfaces
1231 let mut visitor = PrivateItemsInPublicInterfacesVisitor {
1233 old_error_set: &visitor.old_error_set,
1234 inner_visibility: ty::Visibility::Public,
1236 krate.visit_all_item_likes(&mut DeepVisitor::new(&mut visitor));
1239 visitor.access_levels
1242 __build_diagnostic_array! { librustc_privacy, DIAGNOSTICS }