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 // Do not remove on snapshot creation. Needed for bootstrap. (Issue #22364)
12 #![cfg_attr(stage0, feature(custom_attribute))]
13 #![crate_name = "rustc_privacy"]
14 #![unstable(feature = "rustc_private", issue = "27812")]
16 #![crate_type = "dylib"]
17 #![crate_type = "rlib"]
18 #![doc(html_logo_url = "https://www.rust-lang.org/logos/rust-logo-128x128-blk-v2.png",
19 html_favicon_url = "https://doc.rust-lang.org/favicon.ico",
20 html_root_url = "https://doc.rust-lang.org/nightly/")]
22 #![feature(rustc_diagnostic_macros)]
23 #![feature(rustc_private)]
24 #![feature(staged_api)]
26 #[macro_use] extern crate log;
27 #[macro_use] extern crate syntax;
30 extern crate rustc_front;
32 use self::PrivacyResult::*;
33 use self::FieldName::*;
35 use std::mem::replace;
38 use rustc_front::visit::{self, Visitor};
40 use rustc::middle::def;
41 use rustc::middle::def_id::DefId;
42 use rustc::middle::privacy::ImportUse::*;
43 use rustc::middle::privacy::LastPrivate::*;
44 use rustc::middle::privacy::PrivateDep::*;
45 use rustc::middle::privacy::{ExternalExports, ExportedItems, PublicItems};
46 use rustc::middle::ty::{self, Ty};
47 use rustc::util::nodemap::{NodeMap, NodeSet};
48 use rustc::front::map as ast_map;
51 use syntax::codemap::Span;
55 type Context<'a, 'tcx> = (&'a ty::MethodMap<'tcx>, &'a def::ExportMap);
57 /// Result of a checking operation - None => no errors were found. Some => an
58 /// error and contains the span and message for reporting that error and
59 /// optionally the same for a note about the error.
60 type CheckResult = Option<(Span, String, Option<(Span, String)>)>;
62 ////////////////////////////////////////////////////////////////////////////////
63 /// The parent visitor, used to determine what's the parent of what (node-wise)
64 ////////////////////////////////////////////////////////////////////////////////
66 struct ParentVisitor {
67 parents: NodeMap<ast::NodeId>,
68 curparent: ast::NodeId,
71 impl<'v> Visitor<'v> for ParentVisitor {
72 fn visit_item(&mut self, item: &hir::Item) {
73 self.parents.insert(item.id, self.curparent);
75 let prev = self.curparent;
77 hir::ItemMod(..) => { self.curparent = item.id; }
78 // Enum variants are parented to the enum definition itself because
79 // they inherit privacy
80 hir::ItemEnum(ref def, _) => {
81 for variant in &def.variants {
82 // The parent is considered the enclosing enum because the
83 // enum will dictate the privacy visibility of this variant
85 self.parents.insert(variant.node.id, item.id);
89 // Trait methods are always considered "public", but if the trait is
90 // private then we need some private item in the chain from the
91 // method to the root. In this case, if the trait is private, then
92 // parent all the methods to the trait to indicate that they're
94 hir::ItemTrait(_, _, _, ref trait_items) if item.vis != hir::Public => {
95 for trait_item in trait_items {
96 self.parents.insert(trait_item.id, item.id);
102 visit::walk_item(self, item);
103 self.curparent = prev;
106 fn visit_foreign_item(&mut self, a: &hir::ForeignItem) {
107 self.parents.insert(a.id, self.curparent);
108 visit::walk_foreign_item(self, a);
111 fn visit_fn(&mut self, a: visit::FnKind<'v>, b: &'v hir::FnDecl,
112 c: &'v hir::Block, d: Span, id: ast::NodeId) {
113 // We already took care of some trait methods above, otherwise things
114 // like impl methods and pub trait methods are parented to the
115 // containing module, not the containing trait.
116 if !self.parents.contains_key(&id) {
117 self.parents.insert(id, self.curparent);
119 visit::walk_fn(self, a, b, c, d);
122 fn visit_impl_item(&mut self, ii: &'v hir::ImplItem) {
123 // visit_fn handles methods, but associated consts have to be handled
125 if !self.parents.contains_key(&ii.id) {
126 self.parents.insert(ii.id, self.curparent);
128 visit::walk_impl_item(self, ii);
131 fn visit_struct_def(&mut self, s: &hir::StructDef, _: ast::Name,
132 _: &'v hir::Generics, n: ast::NodeId) {
133 // Struct constructors are parented to their struct definitions because
134 // they essentially are the struct definitions.
136 Some(id) => { self.parents.insert(id, n); }
140 // While we have the id of the struct definition, go ahead and parent
142 for field in &s.fields {
143 self.parents.insert(field.node.id, self.curparent);
145 visit::walk_struct_def(self, s)
149 ////////////////////////////////////////////////////////////////////////////////
150 /// The embargo visitor, used to determine the exports of the ast
151 ////////////////////////////////////////////////////////////////////////////////
153 struct EmbargoVisitor<'a, 'tcx: 'a> {
154 tcx: &'a ty::ctxt<'tcx>,
155 export_map: &'a def::ExportMap,
157 // This flag is an indicator of whether the previous item in the
158 // hierarchical chain was exported or not. This is the indicator of whether
159 // children should be exported as well. Note that this can flip from false
160 // to true if a reexported module is entered (or an action similar).
163 // This is a list of all exported items in the AST. An exported item is any
164 // function/method/item which is usable by external crates. This essentially
165 // means that the result is "public all the way down", but the "path down"
166 // may jump across private boundaries through reexport statements.
167 exported_items: ExportedItems,
169 // This sets contains all the destination nodes which are publicly
170 // re-exported. This is *not* a set of all reexported nodes, only a set of
171 // all nodes which are reexported *and* reachable from external crates. This
172 // means that the destination of the reexport is exported, and hence the
173 // destination must also be exported.
176 // These two fields are closely related to one another in that they are only
177 // used for generation of the 'PublicItems' set, not for privacy checking at
179 public_items: PublicItems,
183 impl<'a, 'tcx> EmbargoVisitor<'a, 'tcx> {
184 // There are checks inside of privacy which depend on knowing whether a
185 // trait should be exported or not. The two current consumers of this are:
187 // 1. Should default methods of a trait be exported?
188 // 2. Should the methods of an implementation of a trait be exported?
190 // The answer to both of these questions partly rely on whether the trait
191 // itself is exported or not. If the trait is somehow exported, then the
192 // answers to both questions must be yes. Right now this question involves
193 // more analysis than is currently done in rustc, so we conservatively
194 // answer "yes" so that all traits need to be exported.
195 fn exported_trait(&self, _id: ast::NodeId) -> bool {
200 impl<'a, 'tcx, 'v> Visitor<'v> for EmbargoVisitor<'a, 'tcx> {
201 fn visit_item(&mut self, item: &hir::Item) {
202 let orig_all_pub = self.prev_public;
203 self.prev_public = orig_all_pub && item.vis == hir::Public;
204 if self.prev_public {
205 self.public_items.insert(item.id);
208 let orig_all_exported = self.prev_exported;
210 // impls/extern blocks do not break the "public chain" because they
211 // cannot have visibility qualifiers on them anyway
212 hir::ItemImpl(..) | hir::ItemDefaultImpl(..) | hir::ItemForeignMod(..) => {}
214 // Traits are a little special in that even if they themselves are
215 // not public they may still be exported.
216 hir::ItemTrait(..) => {
217 self.prev_exported = self.exported_trait(item.id);
220 // Private by default, hence we only retain the "public chain" if
221 // `pub` is explicitly listed.
224 (orig_all_exported && item.vis == hir::Public) ||
225 self.reexports.contains(&item.id);
229 let public_first = self.prev_exported &&
230 self.exported_items.insert(item.id);
233 // Enum variants inherit from their parent, so if the enum is
234 // public all variants are public unless they're explicitly priv
235 hir::ItemEnum(ref def, _) if public_first => {
236 for variant in &def.variants {
237 self.exported_items.insert(variant.node.id);
238 self.public_items.insert(variant.node.id);
242 // Implementations are a little tricky to determine what's exported
243 // out of them. Here's a few cases which are currently defined:
245 // * Impls for private types do not need to export their methods
246 // (either public or private methods)
248 // * Impls for public types only have public methods exported
250 // * Public trait impls for public types must have all methods
253 // * Private trait impls for public types can be ignored
255 // * Public trait impls for private types have their methods
256 // exported. I'm not entirely certain that this is the correct
257 // thing to do, but I have seen use cases of where this will cause
258 // undefined symbols at linkage time if this case is not handled.
260 // * Private trait impls for private types can be completely ignored
261 hir::ItemImpl(_, _, _, _, ref ty, ref impl_items) => {
262 let public_ty = match ty.node {
264 match self.tcx.def_map.borrow().get(&ty.id).unwrap().full_def() {
265 def::DefPrimTy(..) => true,
267 let did = def.def_id();
269 self.exported_items.contains(&did.node)
275 let tr = self.tcx.impl_trait_ref(DefId::local(item.id));
276 let public_trait = tr.clone().map_or(false, |tr| {
277 !tr.def_id.is_local() ||
278 self.exported_items.contains(&tr.def_id.node)
281 if public_ty || public_trait {
282 for impl_item in impl_items {
283 match impl_item.node {
284 hir::ConstImplItem(..) => {
285 if (public_ty && impl_item.vis == hir::Public)
287 self.exported_items.insert(impl_item.id);
290 hir::MethodImplItem(ref sig, _) => {
291 let meth_public = match sig.explicit_self.node {
292 hir::SelfStatic => public_ty,
294 } && impl_item.vis == hir::Public;
295 if meth_public || tr.is_some() {
296 self.exported_items.insert(impl_item.id);
299 hir::TypeImplItem(_) => {}
305 // Default methods on traits are all public so long as the trait
307 hir::ItemTrait(_, _, _, ref trait_items) if public_first => {
308 for trait_item in trait_items {
309 debug!("trait item {}", trait_item.id);
310 self.exported_items.insert(trait_item.id);
314 // Struct constructors are public if the struct is all public.
315 hir::ItemStruct(ref def, _) if public_first => {
317 Some(id) => { self.exported_items.insert(id); }
320 // fields can be public or private, so lets check
321 for field in &def.fields {
322 let vis = match field.node.kind {
323 hir::NamedField(_, vis) | hir::UnnamedField(vis) => vis
325 if vis == hir::Public {
326 self.public_items.insert(field.node.id);
331 hir::ItemTy(ref ty, _) if public_first => {
332 if let hir::TyPath(..) = ty.node {
333 match self.tcx.def_map.borrow().get(&ty.id).unwrap().full_def() {
334 def::DefPrimTy(..) | def::DefTyParam(..) => {},
336 let did = def.def_id();
338 self.exported_items.insert(did.node);
348 visit::walk_item(self, item);
350 self.prev_exported = orig_all_exported;
351 self.prev_public = orig_all_pub;
354 fn visit_foreign_item(&mut self, a: &hir::ForeignItem) {
355 if (self.prev_exported && a.vis == hir::Public) || self.reexports.contains(&a.id) {
356 self.exported_items.insert(a.id);
360 fn visit_mod(&mut self, m: &hir::Mod, _sp: Span, id: ast::NodeId) {
361 // This code is here instead of in visit_item so that the
362 // crate module gets processed as well.
363 if self.prev_exported {
364 assert!(self.export_map.contains_key(&id), "wut {}", id);
365 for export in self.export_map.get(&id).unwrap() {
366 if export.def_id.is_local() {
367 self.reexports.insert(export.def_id.node);
371 visit::walk_mod(self, m)
375 ////////////////////////////////////////////////////////////////////////////////
376 /// The privacy visitor, where privacy checks take place (violations reported)
377 ////////////////////////////////////////////////////////////////////////////////
379 struct PrivacyVisitor<'a, 'tcx: 'a> {
380 tcx: &'a ty::ctxt<'tcx>,
381 curitem: ast::NodeId,
383 parents: NodeMap<ast::NodeId>,
384 external_exports: ExternalExports,
390 DisallowedBy(ast::NodeId),
394 UnnamedField(usize), // index
395 NamedField(ast::Name),
398 impl<'a, 'tcx> PrivacyVisitor<'a, 'tcx> {
399 // used when debugging
400 fn nodestr(&self, id: ast::NodeId) -> String {
401 self.tcx.map.node_to_string(id).to_string()
404 // Determines whether the given definition is public from the point of view
405 // of the current item.
406 fn def_privacy(&self, did: DefId) -> PrivacyResult {
408 if self.external_exports.contains(&did) {
409 debug!("privacy - {:?} was externally exported", did);
412 debug!("privacy - is {:?} a public method", did);
414 return match self.tcx.impl_or_trait_items.borrow().get(&did) {
415 Some(&ty::ConstTraitItem(ref ac)) => {
416 debug!("privacy - it's a const: {:?}", *ac);
418 ty::TraitContainer(id) => {
419 debug!("privacy - recursing on trait {:?}", id);
422 ty::ImplContainer(id) => {
423 match self.tcx.impl_trait_ref(id) {
425 debug!("privacy - impl of trait {:?}", id);
426 self.def_privacy(t.def_id)
429 debug!("privacy - found inherent \
430 associated constant {:?}",
432 if ac.vis == hir::Public {
442 Some(&ty::MethodTraitItem(ref meth)) => {
443 debug!("privacy - well at least it's a method: {:?}",
445 match meth.container {
446 ty::TraitContainer(id) => {
447 debug!("privacy - recursing on trait {:?}", id);
450 ty::ImplContainer(id) => {
451 match self.tcx.impl_trait_ref(id) {
453 debug!("privacy - impl of trait {:?}", id);
454 self.def_privacy(t.def_id)
457 debug!("privacy - found a method {:?}",
459 if meth.vis == hir::Public {
469 Some(&ty::TypeTraitItem(ref typedef)) => {
470 match typedef.container {
471 ty::TraitContainer(id) => {
472 debug!("privacy - recursing on trait {:?}", id);
475 ty::ImplContainer(id) => {
476 match self.tcx.impl_trait_ref(id) {
478 debug!("privacy - impl of trait {:?}", id);
479 self.def_privacy(t.def_id)
482 debug!("privacy - found a typedef {:?}",
484 if typedef.vis == hir::Public {
495 debug!("privacy - nope, not even a method");
501 debug!("privacy - local {} not public all the way down",
502 self.tcx.map.node_to_string(did.node));
503 // return quickly for things in the same module
504 if self.parents.get(&did.node) == self.parents.get(&self.curitem) {
505 debug!("privacy - same parent, we're done here");
509 // We now know that there is at least one private member between the
510 // destination and the root.
511 let mut closest_private_id = did.node;
513 debug!("privacy - examining {}", self.nodestr(closest_private_id));
514 let vis = match self.tcx.map.find(closest_private_id) {
515 // If this item is a method, then we know for sure that it's an
516 // actual method and not a static method. The reason for this is
517 // that these cases are only hit in the ExprMethodCall
518 // expression, and ExprCall will have its path checked later
519 // (the path of the trait/impl) if it's a static method.
521 // With this information, then we can completely ignore all
522 // trait methods. The privacy violation would be if the trait
523 // couldn't get imported, not if the method couldn't be used
524 // (all trait methods are public).
526 // However, if this is an impl method, then we dictate this
527 // decision solely based on the privacy of the method
529 // FIXME(#10573) is this the right behavior? Why not consider
530 // where the method was defined?
531 Some(ast_map::NodeImplItem(ii)) => {
533 hir::ConstImplItem(..) |
534 hir::MethodImplItem(..) => {
535 let imp = self.tcx.map
536 .get_parent_did(closest_private_id);
537 match self.tcx.impl_trait_ref(imp) {
538 Some(..) => return Allowable,
539 _ if ii.vis == hir::Public => {
545 hir::TypeImplItem(_) => return Allowable,
548 Some(ast_map::NodeTraitItem(_)) => {
552 // This is not a method call, extract the visibility as one
553 // would normally look at it
554 Some(ast_map::NodeItem(it)) => it.vis,
555 Some(ast_map::NodeForeignItem(_)) => {
556 self.tcx.map.get_foreign_vis(closest_private_id)
558 Some(ast_map::NodeVariant(..)) => {
559 hir::Public // need to move up a level (to the enum)
563 if vis != hir::Public { break }
564 // if we've reached the root, then everything was allowable and this
566 if closest_private_id == ast::CRATE_NODE_ID { return Allowable }
567 closest_private_id = *self.parents.get(&closest_private_id).unwrap();
569 // If we reached the top, then we were public all the way down and
570 // we can allow this access.
571 if closest_private_id == ast::DUMMY_NODE_ID { return Allowable }
573 debug!("privacy - closest priv {}", self.nodestr(closest_private_id));
574 if self.private_accessible(closest_private_id) {
577 DisallowedBy(closest_private_id)
581 /// For a local private node in the AST, this function will determine
582 /// whether the node is accessible by the current module that iteration is
584 fn private_accessible(&self, id: ast::NodeId) -> bool {
585 let parent = *self.parents.get(&id).unwrap();
586 debug!("privacy - accessible parent {}", self.nodestr(parent));
588 // After finding `did`'s closest private member, we roll ourselves back
589 // to see if this private member's parent is anywhere in our ancestry.
590 // By the privacy rules, we can access all of our ancestor's private
591 // members, so that's why we test the parent, and not the did itself.
592 let mut cur = self.curitem;
594 debug!("privacy - questioning {}, {}", self.nodestr(cur), cur);
596 // If the relevant parent is in our history, then we're allowed
597 // to look inside any of our ancestor's immediate private items,
598 // so this access is valid.
599 x if x == parent => return true,
601 // If we've reached the root, then we couldn't access this item
602 // in the first place
603 ast::DUMMY_NODE_ID => return false,
609 cur = *self.parents.get(&cur).unwrap();
613 fn report_error(&self, result: CheckResult) -> bool {
616 Some((span, msg, note)) => {
617 self.tcx.sess.span_err(span, &msg[..]);
619 Some((span, msg)) => {
620 self.tcx.sess.span_note(span, &msg[..])
629 /// Guarantee that a particular definition is public. Returns a CheckResult
630 /// which contains any errors found. These can be reported using `report_error`.
631 /// If the result is `None`, no errors were found.
632 fn ensure_public(&self, span: Span, to_check: DefId,
633 source_did: Option<DefId>, msg: &str) -> CheckResult {
634 let id = match self.def_privacy(to_check) {
635 ExternallyDenied => {
636 return Some((span, format!("{} is private", msg), None))
638 Allowable => return None,
639 DisallowedBy(id) => id,
642 // If we're disallowed by a particular id, then we attempt to give a
643 // nice error message to say why it was disallowed. It was either
644 // because the item itself is private or because its parent is private
645 // and its parent isn't in our ancestry.
646 let (err_span, err_msg) = if id == source_did.unwrap_or(to_check).node {
647 return Some((span, format!("{} is private", msg), None));
649 (span, format!("{} is inaccessible", msg))
651 let item = match self.tcx.map.find(id) {
652 Some(ast_map::NodeItem(item)) => {
654 // If an impl disallowed this item, then this is resolve's
655 // way of saying that a struct/enum's static method was
656 // invoked, and the struct/enum itself is private. Crawl
657 // back up the chains to find the relevant struct/enum that
659 hir::ItemImpl(_, _, _, _, ref ty, _) => {
661 hir::TyPath(..) => {}
662 _ => return Some((err_span, err_msg, None)),
664 let def = self.tcx.def_map.borrow().get(&ty.id).unwrap().full_def();
665 let did = def.def_id();
666 assert!(did.is_local());
667 match self.tcx.map.get(did.node) {
668 ast_map::NodeItem(item) => item,
669 _ => self.tcx.sess.span_bug(item.span,
670 "path is not an item")
676 Some(..) | None => return Some((err_span, err_msg, None)),
678 let desc = match item.node {
679 hir::ItemMod(..) => "module",
680 hir::ItemTrait(..) => "trait",
681 hir::ItemStruct(..) => "struct",
682 hir::ItemEnum(..) => "enum",
683 _ => return Some((err_span, err_msg, None))
685 let msg = format!("{} `{}` is private", desc, item.name);
686 Some((err_span, err_msg, Some((span, msg))))
689 // Checks that a field is in scope.
690 fn check_field(&mut self,
692 def: ty::AdtDef<'tcx>,
693 v: ty::VariantDef<'tcx>,
695 let field = match name {
696 NamedField(f_name) => {
697 debug!("privacy - check named field {} in struct {:?}", f_name, def);
698 v.field_named(f_name)
700 UnnamedField(idx) => &v.fields[idx]
702 if field.vis == hir::Public ||
703 (field.did.is_local() && self.private_accessible(field.did.node)) {
707 let struct_desc = match def.adt_kind() {
708 ty::AdtKind::Struct =>
709 format!("struct `{}`", self.tcx.item_path_str(def.did)),
710 // struct variant fields have inherited visibility
711 ty::AdtKind::Enum => return
713 let msg = match name {
714 NamedField(name) => format!("field `{}` of {} is private",
716 UnnamedField(idx) => format!("field #{} of {} is private",
717 idx + 1, struct_desc),
719 span_err!(self.tcx.sess, span, E0451,
723 // Given the ID of a method, checks to ensure it's in scope.
724 fn check_static_method(&mut self,
728 self.report_error(self.ensure_public(span,
731 &format!("method `{}`",
735 // Checks that a path is in scope.
736 fn check_path(&mut self, span: Span, path_id: ast::NodeId, last: ast::Name) {
737 debug!("privacy - path {}", self.nodestr(path_id));
738 let path_res = *self.tcx.def_map.borrow().get(&path_id).unwrap();
739 let ck = |tyname: &str| {
740 let ck_public = |def: DefId| {
741 debug!("privacy - ck_public {:?}", def);
742 let origdid = path_res.def_id();
743 self.ensure_public(span,
746 &format!("{} `{}`", tyname, last))
749 match path_res.last_private {
750 LastMod(AllPublic) => {},
751 LastMod(DependsOn(def)) => {
752 self.report_error(ck_public(def));
754 LastImport { value_priv,
755 value_used: check_value,
757 type_used: check_type } => {
758 // This dance with found_error is because we don't want to
759 // report a privacy error twice for the same directive.
760 let found_error = match (type_priv, check_type) {
761 (Some(DependsOn(def)), Used) => {
762 !self.report_error(ck_public(def))
767 match (value_priv, check_value) {
768 (Some(DependsOn(def)), Used) => {
769 self.report_error(ck_public(def));
774 // If an import is not used in either namespace, we still
775 // want to check that it could be legal. Therefore we check
776 // in both namespaces and only report an error if both would
777 // be illegal. We only report one error, even if it is
778 // illegal to import from both namespaces.
779 match (value_priv, check_value, type_priv, check_type) {
780 (Some(p), Unused, None, _) |
781 (None, _, Some(p), Unused) => {
784 DependsOn(def) => ck_public(def),
787 self.report_error(p);
790 (Some(v), Unused, Some(t), Unused) => {
793 DependsOn(def) => ck_public(def),
797 DependsOn(def) => ck_public(def),
799 if let (Some(_), Some(t)) = (v, t) {
800 self.report_error(Some(t));
808 // FIXME(#12334) Imports can refer to definitions in both the type and
809 // value namespaces. The privacy information is aware of this, but the
810 // def map is not. Therefore the names we work out below will not always
811 // be accurate and we can get slightly wonky error messages (but type
812 // checking is always correct).
813 match path_res.full_def() {
814 def::DefFn(..) => ck("function"),
815 def::DefStatic(..) => ck("static"),
816 def::DefConst(..) => ck("const"),
817 def::DefAssociatedConst(..) => ck("associated const"),
818 def::DefVariant(..) => ck("variant"),
819 def::DefTy(_, false) => ck("type"),
820 def::DefTy(_, true) => ck("enum"),
821 def::DefTrait(..) => ck("trait"),
822 def::DefStruct(..) => ck("struct"),
823 def::DefMethod(..) => ck("method"),
824 def::DefMod(..) => ck("module"),
829 // Checks that a method is in scope.
830 fn check_method(&mut self, span: Span, method_def_id: DefId,
832 match self.tcx.impl_or_trait_item(method_def_id).container() {
833 ty::ImplContainer(_) => {
834 self.check_static_method(span, method_def_id, name)
836 // Trait methods are always accessible if the trait is in scope.
837 ty::TraitContainer(_) => {}
842 impl<'a, 'tcx, 'v> Visitor<'v> for PrivacyVisitor<'a, 'tcx> {
843 fn visit_item(&mut self, item: &hir::Item) {
844 let orig_curitem = replace(&mut self.curitem, item.id);
845 visit::walk_item(self, item);
846 self.curitem = orig_curitem;
849 fn visit_expr(&mut self, expr: &hir::Expr) {
851 hir::ExprField(ref base, name) => {
852 if let ty::TyStruct(def, _) = self.tcx.expr_ty_adjusted(&**base).sty {
853 self.check_field(expr.span,
855 def.struct_variant(),
856 NamedField(name.node));
859 hir::ExprTupField(ref base, idx) => {
860 if let ty::TyStruct(def, _) = self.tcx.expr_ty_adjusted(&**base).sty {
861 self.check_field(expr.span,
863 def.struct_variant(),
864 UnnamedField(idx.node));
867 hir::ExprMethodCall(name, _, _) => {
868 let method_call = ty::MethodCall::expr(expr.id);
869 let method = self.tcx.tables.borrow().method_map[&method_call];
870 debug!("(privacy checking) checking impl method");
871 self.check_method(expr.span, method.def_id, name.node);
873 hir::ExprStruct(..) => {
874 let adt = self.tcx.expr_ty(expr).ty_adt_def().unwrap();
875 let variant = adt.variant_of_def(self.tcx.resolve_expr(expr));
876 // RFC 736: ensure all unmentioned fields are visible.
877 // Rather than computing the set of unmentioned fields
878 // (i.e. `all_fields - fields`), just check them all.
879 for field in &variant.fields {
880 self.check_field(expr.span, adt, variant, NamedField(field.name));
883 hir::ExprPath(..) => {
885 if let def::DefStruct(_) = self.tcx.resolve_expr(expr) {
886 let expr_ty = self.tcx.expr_ty(expr);
887 let def = match expr_ty.sty {
888 ty::TyBareFn(_, &ty::BareFnTy { sig: ty::Binder(ty::FnSig {
889 output: ty::FnConverging(ty), ..
892 }.ty_adt_def().unwrap();
893 let any_priv = def.struct_variant().fields.iter().any(|f| {
894 f.vis != hir::Public && (
896 !self.private_accessible(f.did.node))
900 span_err!(self.tcx.sess, expr.span, E0450,
901 "cannot invoke tuple struct constructor with private \
909 visit::walk_expr(self, expr);
912 fn visit_pat(&mut self, pattern: &hir::Pat) {
913 // Foreign functions do not have their patterns mapped in the def_map,
914 // and there's nothing really relevant there anyway, so don't bother
915 // checking privacy. If you can name the type then you can pass it to an
916 // external C function anyway.
917 if self.in_foreign { return }
920 hir::PatStruct(_, ref fields, _) => {
921 let adt = self.tcx.pat_ty(pattern).ty_adt_def().unwrap();
922 let def = self.tcx.def_map.borrow().get(&pattern.id).unwrap().full_def();
923 let variant = adt.variant_of_def(def);
924 for field in fields {
925 self.check_field(pattern.span, adt, variant,
926 NamedField(field.node.name));
930 // Patterns which bind no fields are allowable (the path is check
932 hir::PatEnum(_, Some(ref fields)) => {
933 match self.tcx.pat_ty(pattern).sty {
934 ty::TyStruct(def, _) => {
935 for (i, field) in fields.iter().enumerate() {
936 if let hir::PatWild(..) = field.node {
939 self.check_field(field.span,
941 def.struct_variant(),
946 // enum fields have no privacy at this time
955 visit::walk_pat(self, pattern);
958 fn visit_foreign_item(&mut self, fi: &hir::ForeignItem) {
959 self.in_foreign = true;
960 visit::walk_foreign_item(self, fi);
961 self.in_foreign = false;
964 fn visit_path(&mut self, path: &hir::Path, id: ast::NodeId) {
965 if !path.segments.is_empty() {
966 self.check_path(path.span, id, path.segments.last().unwrap().identifier.name);
967 visit::walk_path(self, path);
971 fn visit_path_list_item(&mut self, prefix: &hir::Path, item: &hir::PathListItem) {
972 let name = if let hir::PathListIdent { name, .. } = item.node {
974 } else if !prefix.segments.is_empty() {
975 prefix.segments.last().unwrap().identifier.name
977 self.tcx.sess.bug("`self` import in an import list with empty prefix");
979 self.check_path(item.span, item.node.id(), name);
980 visit::walk_path_list_item(self, prefix, item);
984 ////////////////////////////////////////////////////////////////////////////////
985 /// The privacy sanity check visitor, ensures unnecessary visibility isn't here
986 ////////////////////////////////////////////////////////////////////////////////
988 struct SanePrivacyVisitor<'a, 'tcx: 'a> {
989 tcx: &'a ty::ctxt<'tcx>,
993 impl<'a, 'tcx, 'v> Visitor<'v> for SanePrivacyVisitor<'a, 'tcx> {
994 fn visit_item(&mut self, item: &hir::Item) {
996 self.check_all_inherited(item);
998 self.check_sane_privacy(item);
1001 let in_fn = self.in_fn;
1002 let orig_in_fn = replace(&mut self.in_fn, match item.node {
1003 hir::ItemMod(..) => false, // modules turn privacy back on
1004 _ => in_fn, // otherwise we inherit
1006 visit::walk_item(self, item);
1007 self.in_fn = orig_in_fn;
1010 fn visit_fn(&mut self, fk: visit::FnKind<'v>, fd: &'v hir::FnDecl,
1011 b: &'v hir::Block, s: Span, _: ast::NodeId) {
1012 // This catches both functions and methods
1013 let orig_in_fn = replace(&mut self.in_fn, true);
1014 visit::walk_fn(self, fk, fd, b, s);
1015 self.in_fn = orig_in_fn;
1019 impl<'a, 'tcx> SanePrivacyVisitor<'a, 'tcx> {
1020 /// Validates all of the visibility qualifiers placed on the item given. This
1021 /// ensures that there are no extraneous qualifiers that don't actually do
1022 /// anything. In theory these qualifiers wouldn't parse, but that may happen
1023 /// later on down the road...
1024 fn check_sane_privacy(&self, item: &hir::Item) {
1026 let check_inherited = |sp: Span, vis: hir::Visibility, note: &str| {
1027 if vis != hir::Inherited {
1028 span_err!(tcx.sess, sp, E0449,
1029 "unnecessary visibility qualifier");
1030 if !note.is_empty() {
1031 tcx.sess.span_note(sp, note);
1036 // implementations of traits don't need visibility qualifiers because
1037 // that's controlled by having the trait in scope.
1038 hir::ItemImpl(_, _, _, Some(..), _, ref impl_items) => {
1039 check_inherited(item.span, item.vis,
1040 "visibility qualifiers have no effect on trait \
1042 for impl_item in impl_items {
1043 check_inherited(impl_item.span, impl_item.vis, "");
1047 hir::ItemImpl(..) => {
1048 check_inherited(item.span, item.vis,
1049 "place qualifiers on individual methods instead");
1051 hir::ItemForeignMod(..) => {
1052 check_inherited(item.span, item.vis,
1053 "place qualifiers on individual functions \
1058 hir::ItemTrait(..) | hir::ItemDefaultImpl(..) |
1059 hir::ItemConst(..) | hir::ItemStatic(..) | hir::ItemStruct(..) |
1060 hir::ItemFn(..) | hir::ItemMod(..) | hir::ItemTy(..) |
1061 hir::ItemExternCrate(_) | hir::ItemUse(_) => {}
1065 /// When inside of something like a function or a method, visibility has no
1066 /// control over anything so this forbids any mention of any visibility
1067 fn check_all_inherited(&self, item: &hir::Item) {
1069 fn check_inherited(tcx: &ty::ctxt, sp: Span, vis: hir::Visibility) {
1070 if vis != hir::Inherited {
1071 span_err!(tcx.sess, sp, E0447,
1072 "visibility has no effect inside functions");
1075 let check_struct = |def: &hir::StructDef| {
1076 for f in &def.fields {
1078 hir::NamedField(_, p) => check_inherited(tcx, f.span, p),
1079 hir::UnnamedField(..) => {}
1083 check_inherited(tcx, item.span, item.vis);
1085 hir::ItemImpl(_, _, _, _, _, ref impl_items) => {
1086 for impl_item in impl_items {
1087 match impl_item.node {
1088 hir::MethodImplItem(..) => {
1089 check_inherited(tcx, impl_item.span, impl_item.vis);
1095 hir::ItemForeignMod(ref fm) => {
1096 for i in &fm.items {
1097 check_inherited(tcx, i.span, i.vis);
1101 hir::ItemStruct(ref def, _) => check_struct(&**def),
1104 hir::ItemExternCrate(_) | hir::ItemUse(_) |
1105 hir::ItemTrait(..) | hir::ItemDefaultImpl(..) |
1106 hir::ItemStatic(..) | hir::ItemConst(..) |
1107 hir::ItemFn(..) | hir::ItemMod(..) | hir::ItemTy(..) => {}
1112 struct VisiblePrivateTypesVisitor<'a, 'tcx: 'a> {
1113 tcx: &'a ty::ctxt<'tcx>,
1114 exported_items: &'a ExportedItems,
1115 public_items: &'a PublicItems,
1119 struct CheckTypeForPrivatenessVisitor<'a, 'b: 'a, 'tcx: 'b> {
1120 inner: &'a VisiblePrivateTypesVisitor<'b, 'tcx>,
1121 /// whether the type refers to private types.
1122 contains_private: bool,
1123 /// whether we've recurred at all (i.e. if we're pointing at the
1124 /// first type on which visit_ty was called).
1125 at_outer_type: bool,
1126 // whether that first type is a public path.
1127 outer_type_is_public_path: bool,
1130 impl<'a, 'tcx> VisiblePrivateTypesVisitor<'a, 'tcx> {
1131 fn path_is_private_type(&self, path_id: ast::NodeId) -> bool {
1132 let did = match self.tcx.def_map.borrow().get(&path_id).map(|d| d.full_def()) {
1133 // `int` etc. (None doesn't seem to occur.)
1134 None | Some(def::DefPrimTy(..)) => return false,
1135 Some(def) => def.def_id(),
1137 // A path can only be private if:
1138 // it's in this crate...
1139 if !did.is_local() {
1143 // .. and it corresponds to a private type in the AST (this returns
1144 // None for type parameters)
1145 match self.tcx.map.find(did.node) {
1146 Some(ast_map::NodeItem(ref item)) => item.vis != hir::Public,
1147 Some(_) | None => false,
1151 fn trait_is_public(&self, trait_id: ast::NodeId) -> bool {
1152 // FIXME: this would preferably be using `exported_items`, but all
1153 // traits are exported currently (see `EmbargoVisitor.exported_trait`)
1154 self.public_items.contains(&trait_id)
1157 fn check_ty_param_bound(&self,
1158 ty_param_bound: &hir::TyParamBound) {
1159 if let hir::TraitTyParamBound(ref trait_ref, _) = *ty_param_bound {
1160 if !self.tcx.sess.features.borrow().visible_private_types &&
1161 self.path_is_private_type(trait_ref.trait_ref.ref_id) {
1162 let span = trait_ref.trait_ref.path.span;
1163 span_err!(self.tcx.sess, span, E0445,
1164 "private trait in exported type parameter bound");
1169 fn item_is_public(&self, id: &ast::NodeId, vis: hir::Visibility) -> bool {
1170 self.exported_items.contains(id) || vis == hir::Public
1174 impl<'a, 'b, 'tcx, 'v> Visitor<'v> for CheckTypeForPrivatenessVisitor<'a, 'b, 'tcx> {
1175 fn visit_ty(&mut self, ty: &hir::Ty) {
1176 if let hir::TyPath(..) = ty.node {
1177 if self.inner.path_is_private_type(ty.id) {
1178 self.contains_private = true;
1179 // found what we're looking for so let's stop
1182 } else if self.at_outer_type {
1183 self.outer_type_is_public_path = true;
1186 self.at_outer_type = false;
1187 visit::walk_ty(self, ty)
1190 // don't want to recurse into [, .. expr]
1191 fn visit_expr(&mut self, _: &hir::Expr) {}
1194 impl<'a, 'tcx, 'v> Visitor<'v> for VisiblePrivateTypesVisitor<'a, 'tcx> {
1195 fn visit_item(&mut self, item: &hir::Item) {
1197 // contents of a private mod can be reexported, so we need
1198 // to check internals.
1199 hir::ItemMod(_) => {}
1201 // An `extern {}` doesn't introduce a new privacy
1202 // namespace (the contents have their own privacies).
1203 hir::ItemForeignMod(_) => {}
1205 hir::ItemTrait(_, _, ref bounds, _) => {
1206 if !self.trait_is_public(item.id) {
1210 for bound in bounds.iter() {
1211 self.check_ty_param_bound(bound)
1215 // impls need some special handling to try to offer useful
1216 // error messages without (too many) false positives
1217 // (i.e. we could just return here to not check them at
1218 // all, or some worse estimation of whether an impl is
1219 // publicly visible).
1220 hir::ItemImpl(_, _, ref g, ref trait_ref, ref self_, ref impl_items) => {
1221 // `impl [... for] Private` is never visible.
1222 let self_contains_private;
1223 // impl [... for] Public<...>, but not `impl [... for]
1224 // Vec<Public>` or `(Public,)` etc.
1225 let self_is_public_path;
1227 // check the properties of the Self type:
1229 let mut visitor = CheckTypeForPrivatenessVisitor {
1231 contains_private: false,
1232 at_outer_type: true,
1233 outer_type_is_public_path: false,
1235 visitor.visit_ty(&**self_);
1236 self_contains_private = visitor.contains_private;
1237 self_is_public_path = visitor.outer_type_is_public_path;
1240 // miscellaneous info about the impl
1242 // `true` iff this is `impl Private for ...`.
1243 let not_private_trait =
1244 trait_ref.as_ref().map_or(true, // no trait counts as public trait
1246 let did = self.tcx.trait_ref_to_def_id(tr);
1248 !did.is_local() || self.trait_is_public(did.node)
1251 // `true` iff this is a trait impl or at least one method is public.
1253 // `impl Public { $( fn ...() {} )* }` is not visible.
1255 // This is required over just using the methods' privacy
1256 // directly because we might have `impl<T: Foo<Private>> ...`,
1257 // and we shouldn't warn about the generics if all the methods
1258 // are private (because `T` won't be visible externally).
1259 let trait_or_some_public_method =
1260 trait_ref.is_some() ||
1263 match impl_item.node {
1264 hir::ConstImplItem(..) |
1265 hir::MethodImplItem(..) => {
1266 self.exported_items.contains(&impl_item.id)
1268 hir::TypeImplItem(_) => false,
1272 if !self_contains_private &&
1273 not_private_trait &&
1274 trait_or_some_public_method {
1276 visit::walk_generics(self, g);
1280 for impl_item in impl_items {
1281 // This is where we choose whether to walk down
1282 // further into the impl to check its items. We
1283 // should only walk into public items so that we
1284 // don't erroneously report errors for private
1285 // types in private items.
1286 match impl_item.node {
1287 hir::ConstImplItem(..) |
1288 hir::MethodImplItem(..)
1289 if self.item_is_public(&impl_item.id, impl_item.vis) =>
1291 visit::walk_impl_item(self, impl_item)
1293 hir::TypeImplItem(..) => {
1294 visit::walk_impl_item(self, impl_item)
1301 // Any private types in a trait impl fall into three
1303 // 1. mentioned in the trait definition
1304 // 2. mentioned in the type params/generics
1305 // 3. mentioned in the associated types of the impl
1307 // Those in 1. can only occur if the trait is in
1308 // this crate and will've been warned about on the
1309 // trait definition (there's no need to warn twice
1310 // so we don't check the methods).
1312 // Those in 2. are warned via walk_generics and this
1314 visit::walk_path(self, &tr.path);
1316 // Those in 3. are warned with this call.
1317 for impl_item in impl_items {
1318 if let hir::TypeImplItem(ref ty) = impl_item.node {
1324 } else if trait_ref.is_none() && self_is_public_path {
1325 // impl Public<Private> { ... }. Any public static
1326 // methods will be visible as `Public::foo`.
1327 let mut found_pub_static = false;
1328 for impl_item in impl_items {
1329 match impl_item.node {
1330 hir::ConstImplItem(..) => {
1331 if self.item_is_public(&impl_item.id, impl_item.vis) {
1332 found_pub_static = true;
1333 visit::walk_impl_item(self, impl_item);
1336 hir::MethodImplItem(ref sig, _) => {
1337 if sig.explicit_self.node == hir::SelfStatic &&
1338 self.item_is_public(&impl_item.id, impl_item.vis) {
1339 found_pub_static = true;
1340 visit::walk_impl_item(self, impl_item);
1346 if found_pub_static {
1347 visit::walk_generics(self, g)
1353 // `type ... = ...;` can contain private types, because
1354 // we're introducing a new name.
1355 hir::ItemTy(..) => return,
1357 // not at all public, so we don't care
1358 _ if !self.item_is_public(&item.id, item.vis) => {
1365 // We've carefully constructed it so that if we're here, then
1366 // any `visit_ty`'s will be called on things that are in
1367 // public signatures, i.e. things that we're interested in for
1369 debug!("VisiblePrivateTypesVisitor entering item {:?}", item);
1370 visit::walk_item(self, item);
1373 fn visit_generics(&mut self, generics: &hir::Generics) {
1374 for ty_param in generics.ty_params.iter() {
1375 for bound in ty_param.bounds.iter() {
1376 self.check_ty_param_bound(bound)
1379 for predicate in &generics.where_clause.predicates {
1381 &hir::WherePredicate::BoundPredicate(ref bound_pred) => {
1382 for bound in bound_pred.bounds.iter() {
1383 self.check_ty_param_bound(bound)
1386 &hir::WherePredicate::RegionPredicate(_) => {}
1387 &hir::WherePredicate::EqPredicate(ref eq_pred) => {
1388 self.visit_ty(&*eq_pred.ty);
1394 fn visit_foreign_item(&mut self, item: &hir::ForeignItem) {
1395 if self.exported_items.contains(&item.id) {
1396 visit::walk_foreign_item(self, item)
1400 fn visit_ty(&mut self, t: &hir::Ty) {
1401 debug!("VisiblePrivateTypesVisitor checking ty {:?}", t);
1402 if let hir::TyPath(_, ref p) = t.node {
1403 if !self.tcx.sess.features.borrow().visible_private_types &&
1404 self.path_is_private_type(t.id) {
1405 span_err!(self.tcx.sess, p.span, E0446,
1406 "private type in exported type signature");
1409 visit::walk_ty(self, t)
1412 fn visit_variant(&mut self, v: &hir::Variant, g: &hir::Generics) {
1413 if self.exported_items.contains(&v.node.id) {
1414 self.in_variant = true;
1415 visit::walk_variant(self, v, g);
1416 self.in_variant = false;
1420 fn visit_struct_field(&mut self, s: &hir::StructField) {
1422 hir::NamedField(_, vis) if vis == hir::Public || self.in_variant => {
1423 visit::walk_struct_field(self, s);
1430 // we don't need to introspect into these at all: an
1431 // expression/block context can't possibly contain exported things.
1432 // (Making them no-ops stops us from traversing the whole AST without
1433 // having to be super careful about our `walk_...` calls above.)
1434 fn visit_block(&mut self, _: &hir::Block) {}
1435 fn visit_expr(&mut self, _: &hir::Expr) {}
1438 pub fn check_crate(tcx: &ty::ctxt,
1439 export_map: &def::ExportMap,
1440 external_exports: ExternalExports)
1441 -> (ExportedItems, PublicItems) {
1442 let krate = tcx.map.krate();
1444 // Figure out who everyone's parent is
1445 let mut visitor = ParentVisitor {
1447 curparent: ast::DUMMY_NODE_ID,
1449 visit::walk_crate(&mut visitor, krate);
1451 // Use the parent map to check the privacy of everything
1452 let mut visitor = PrivacyVisitor {
1453 curitem: ast::DUMMY_NODE_ID,
1456 parents: visitor.parents,
1457 external_exports: external_exports,
1459 visit::walk_crate(&mut visitor, krate);
1461 // Sanity check to make sure that all privacy usage and controls are
1463 let mut visitor = SanePrivacyVisitor {
1467 visit::walk_crate(&mut visitor, krate);
1469 tcx.sess.abort_if_errors();
1471 // Build up a set of all exported items in the AST. This is a set of all
1472 // items which are reachable from external crates based on visibility.
1473 let mut visitor = EmbargoVisitor {
1475 exported_items: NodeSet(),
1476 public_items: NodeSet(),
1477 reexports: NodeSet(),
1478 export_map: export_map,
1479 prev_exported: true,
1483 let before = visitor.exported_items.len();
1484 visit::walk_crate(&mut visitor, krate);
1485 if before == visitor.exported_items.len() {
1490 let EmbargoVisitor { exported_items, public_items, .. } = visitor;
1493 let mut visitor = VisiblePrivateTypesVisitor {
1495 exported_items: &exported_items,
1496 public_items: &public_items,
1499 visit::walk_crate(&mut visitor, krate);
1501 return (exported_items, public_items);