#![doc(html_root_url = "https://doc.rust-lang.org/nightly/nightly-rustc/")]
#![feature(associated_type_defaults)]
#![feature(rustc_private)]
#![feature(try_blocks)]
#![feature(let_chains)]
#![recursion_limit = "256"]
#![deny(rustc::untranslatable_diagnostic)]
#![deny(rustc::diagnostic_outside_of_impl)]
#[macro_use]
extern crate tracing;
mod errors;
use rustc_ast::MacroDef;
use rustc_attr as attr;
use rustc_data_structures::fx::FxHashSet;
use rustc_data_structures::intern::Interned;
use rustc_hir as hir;
use rustc_hir::def::{DefKind, Res};
use rustc_hir::def_id::{DefId, LocalDefId, LocalDefIdSet, CRATE_DEF_ID};
use rustc_hir::intravisit::{self, Visitor};
use rustc_hir::{AssocItemKind, HirIdSet, ItemId, Node, PatKind};
use rustc_middle::bug;
use rustc_middle::hir::nested_filter;
use rustc_middle::middle::privacy::{EffectiveVisibilities, Level};
use rustc_middle::span_bug;
use rustc_middle::ty::query::Providers;
use rustc_middle::ty::subst::InternalSubsts;
use rustc_middle::ty::{self, Const, DefIdTree, GenericParamDefKind};
use rustc_middle::ty::{TraitRef, Ty, TyCtxt, TypeSuperVisitable, TypeVisitable, TypeVisitor};
use rustc_session::lint;
use rustc_span::hygiene::Transparency;
use rustc_span::symbol::{kw, sym, Ident};
use rustc_span::Span;
use std::marker::PhantomData;
use std::ops::ControlFlow;
use std::{cmp, fmt, mem};
use errors::{
FieldIsPrivate, FieldIsPrivateLabel, FromPrivateDependencyInPublicInterface, InPublicInterface,
InPublicInterfaceTraits, ItemIsPrivate, PrivateInPublicLint, ReportEffectiveVisibility,
UnnamedItemIsPrivate,
};
////////////////////////////////////////////////////////////////////////////////
/// Generic infrastructure used to implement specific visitors below.
////////////////////////////////////////////////////////////////////////////////
/// Implemented to visit all `DefId`s in a type.
/// Visiting `DefId`s is useful because visibilities and reachabilities are attached to them.
/// The idea is to visit "all components of a type", as documented in
/// .
/// The default type visitor (`TypeVisitor`) does most of the job, but it has some shortcomings.
/// First, it doesn't have overridable `fn visit_trait_ref`, so we have to catch trait `DefId`s
/// manually. Second, it doesn't visit some type components like signatures of fn types, or traits
/// in `impl Trait`, see individual comments in `DefIdVisitorSkeleton::visit_ty`.
trait DefIdVisitor<'tcx> {
type BreakTy = ();
fn tcx(&self) -> TyCtxt<'tcx>;
fn shallow(&self) -> bool {
false
}
fn skip_assoc_tys(&self) -> bool {
false
}
fn visit_def_id(
&mut self,
def_id: DefId,
kind: &str,
descr: &dyn fmt::Display,
) -> ControlFlow;
/// Not overridden, but used to actually visit types and traits.
fn skeleton(&mut self) -> DefIdVisitorSkeleton<'_, 'tcx, Self> {
DefIdVisitorSkeleton {
def_id_visitor: self,
visited_opaque_tys: Default::default(),
dummy: Default::default(),
}
}
fn visit(&mut self, ty_fragment: impl TypeVisitable<'tcx>) -> ControlFlow {
ty_fragment.visit_with(&mut self.skeleton())
}
fn visit_trait(&mut self, trait_ref: TraitRef<'tcx>) -> ControlFlow {
self.skeleton().visit_trait(trait_ref)
}
fn visit_projection_ty(&mut self, projection: ty::AliasTy<'tcx>) -> ControlFlow {
self.skeleton().visit_projection_ty(projection)
}
fn visit_predicates(
&mut self,
predicates: ty::GenericPredicates<'tcx>,
) -> ControlFlow {
self.skeleton().visit_predicates(predicates)
}
}
struct DefIdVisitorSkeleton<'v, 'tcx, V: ?Sized> {
def_id_visitor: &'v mut V,
visited_opaque_tys: FxHashSet,
dummy: PhantomData>,
}
impl<'tcx, V> DefIdVisitorSkeleton<'_, 'tcx, V>
where
V: DefIdVisitor<'tcx> + ?Sized,
{
fn visit_trait(&mut self, trait_ref: TraitRef<'tcx>) -> ControlFlow {
let TraitRef { def_id, substs, .. } = trait_ref;
self.def_id_visitor.visit_def_id(def_id, "trait", &trait_ref.print_only_trait_path())?;
if self.def_id_visitor.shallow() {
ControlFlow::Continue(())
} else {
substs.visit_with(self)
}
}
fn visit_projection_ty(&mut self, projection: ty::AliasTy<'tcx>) -> ControlFlow {
let tcx = self.def_id_visitor.tcx();
let (trait_ref, assoc_substs) =
if tcx.def_kind(projection.def_id) != DefKind::ImplTraitPlaceholder {
projection.trait_ref_and_own_substs(tcx)
} else {
// HACK(RPITIT): Remove this when RPITITs are lowered to regular assoc tys
let def_id = tcx.impl_trait_in_trait_parent(projection.def_id);
let trait_generics = tcx.generics_of(def_id);
(
tcx.mk_trait_ref(def_id, projection.substs.truncate_to(tcx, trait_generics)),
&projection.substs[trait_generics.count()..],
)
};
self.visit_trait(trait_ref)?;
if self.def_id_visitor.shallow() {
ControlFlow::Continue(())
} else {
assoc_substs.iter().try_for_each(|subst| subst.visit_with(self))
}
}
fn visit_predicate(&mut self, predicate: ty::Predicate<'tcx>) -> ControlFlow {
match predicate.kind().skip_binder() {
ty::PredicateKind::Clause(ty::Clause::Trait(ty::TraitPredicate {
trait_ref,
constness: _,
polarity: _,
})) => self.visit_trait(trait_ref),
ty::PredicateKind::Clause(ty::Clause::Projection(ty::ProjectionPredicate {
projection_ty,
term,
})) => {
term.visit_with(self)?;
self.visit_projection_ty(projection_ty)
}
ty::PredicateKind::Clause(ty::Clause::TypeOutlives(ty::OutlivesPredicate(
ty,
_region,
))) => ty.visit_with(self),
ty::PredicateKind::Clause(ty::Clause::RegionOutlives(..)) => ControlFlow::Continue(()),
ty::PredicateKind::ConstEvaluatable(ct) => ct.visit_with(self),
ty::PredicateKind::WellFormed(arg) => arg.visit_with(self),
_ => bug!("unexpected predicate: {:?}", predicate),
}
}
fn visit_predicates(
&mut self,
predicates: ty::GenericPredicates<'tcx>,
) -> ControlFlow {
let ty::GenericPredicates { parent: _, predicates } = predicates;
predicates.iter().try_for_each(|&(predicate, _span)| self.visit_predicate(predicate))
}
}
impl<'tcx, V> TypeVisitor<'tcx> for DefIdVisitorSkeleton<'_, 'tcx, V>
where
V: DefIdVisitor<'tcx> + ?Sized,
{
type BreakTy = V::BreakTy;
fn visit_ty(&mut self, ty: Ty<'tcx>) -> ControlFlow {
let tcx = self.def_id_visitor.tcx();
// InternalSubsts are not visited here because they are visited below
// in `super_visit_with`.
match *ty.kind() {
ty::Adt(ty::AdtDef(Interned(&ty::AdtDefData { did: def_id, .. }, _)), ..)
| ty::Foreign(def_id)
| ty::FnDef(def_id, ..)
| ty::Closure(def_id, ..)
| ty::Generator(def_id, ..) => {
self.def_id_visitor.visit_def_id(def_id, "type", &ty)?;
if self.def_id_visitor.shallow() {
return ControlFlow::Continue(());
}
// Default type visitor doesn't visit signatures of fn types.
// Something like `fn() -> Priv {my_func}` is considered a private type even if
// `my_func` is public, so we need to visit signatures.
if let ty::FnDef(..) = ty.kind() {
tcx.fn_sig(def_id).visit_with(self)?;
}
// Inherent static methods don't have self type in substs.
// Something like `fn() {my_method}` type of the method
// `impl Pub { pub fn my_method() {} }` is considered a private type,
// so we need to visit the self type additionally.
if let Some(assoc_item) = tcx.opt_associated_item(def_id) {
if let Some(impl_def_id) = assoc_item.impl_container(tcx) {
tcx.type_of(impl_def_id).visit_with(self)?;
}
}
}
ty::Alias(ty::Projection, proj) => {
if self.def_id_visitor.skip_assoc_tys() {
// Visitors searching for minimal visibility/reachability want to
// conservatively approximate associated types like `::Alias`
// as visible/reachable even if both `Type` and `Trait` are private.
// Ideally, associated types should be substituted in the same way as
// free type aliases, but this isn't done yet.
return ControlFlow::Continue(());
}
// This will also visit substs if necessary, so we don't need to recurse.
return self.visit_projection_ty(proj);
}
ty::Dynamic(predicates, ..) => {
// All traits in the list are considered the "primary" part of the type
// and are visited by shallow visitors.
for predicate in predicates {
let trait_ref = match predicate.skip_binder() {
ty::ExistentialPredicate::Trait(trait_ref) => trait_ref,
ty::ExistentialPredicate::Projection(proj) => proj.trait_ref(tcx),
ty::ExistentialPredicate::AutoTrait(def_id) => {
ty::ExistentialTraitRef { def_id, substs: InternalSubsts::empty() }
}
};
let ty::ExistentialTraitRef { def_id, substs: _ } = trait_ref;
self.def_id_visitor.visit_def_id(def_id, "trait", &trait_ref)?;
}
}
ty::Alias(ty::Opaque, ty::AliasTy { def_id, .. }) => {
// Skip repeated `Opaque`s to avoid infinite recursion.
if self.visited_opaque_tys.insert(def_id) {
// The intent is to treat `impl Trait1 + Trait2` identically to
// `dyn Trait1 + Trait2`. Therefore we ignore def-id of the opaque type itself
// (it either has no visibility, or its visibility is insignificant, like
// visibilities of type aliases) and recurse into bounds instead to go
// through the trait list (default type visitor doesn't visit those traits).
// All traits in the list are considered the "primary" part of the type
// and are visited by shallow visitors.
self.visit_predicates(ty::GenericPredicates {
parent: None,
predicates: tcx.explicit_item_bounds(def_id),
})?;
}
}
// These types don't have their own def-ids (but may have subcomponents
// with def-ids that should be visited recursively).
ty::Bool
| ty::Char
| ty::Int(..)
| ty::Uint(..)
| ty::Float(..)
| ty::Str
| ty::Never
| ty::Array(..)
| ty::Slice(..)
| ty::Tuple(..)
| ty::RawPtr(..)
| ty::Ref(..)
| ty::FnPtr(..)
| ty::Param(..)
| ty::Error(_)
| ty::GeneratorWitness(..) => {}
ty::Bound(..) | ty::Placeholder(..) | ty::Infer(..) => {
bug!("unexpected type: {:?}", ty)
}
}
if self.def_id_visitor.shallow() {
ControlFlow::Continue(())
} else {
ty.super_visit_with(self)
}
}
fn visit_const(&mut self, c: Const<'tcx>) -> ControlFlow {
let tcx = self.def_id_visitor.tcx();
tcx.expand_abstract_consts(c).super_visit_with(self)
}
}
fn min(vis1: ty::Visibility, vis2: ty::Visibility, tcx: TyCtxt<'_>) -> ty::Visibility {
if vis1.is_at_least(vis2, tcx) { vis2 } else { vis1 }
}
////////////////////////////////////////////////////////////////////////////////
/// Visitor used to determine impl visibility and reachability.
////////////////////////////////////////////////////////////////////////////////
struct FindMin<'a, 'tcx, VL: VisibilityLike> {
tcx: TyCtxt<'tcx>,
effective_visibilities: &'a EffectiveVisibilities,
min: VL,
}
impl<'a, 'tcx, VL: VisibilityLike> DefIdVisitor<'tcx> for FindMin<'a, 'tcx, VL> {
fn tcx(&self) -> TyCtxt<'tcx> {
self.tcx
}
fn shallow(&self) -> bool {
VL::SHALLOW
}
fn skip_assoc_tys(&self) -> bool {
true
}
fn visit_def_id(
&mut self,
def_id: DefId,
_kind: &str,
_descr: &dyn fmt::Display,
) -> ControlFlow {
if let Some(def_id) = def_id.as_local() {
self.min = VL::new_min(self, def_id);
}
ControlFlow::Continue(())
}
}
trait VisibilityLike: Sized {
const MAX: Self;
const SHALLOW: bool = false;
fn new_min(find: &FindMin<'_, '_, Self>, def_id: LocalDefId) -> Self;
// Returns an over-approximation (`skip_assoc_tys` = true) of visibility due to
// associated types for which we can't determine visibility precisely.
fn of_impl(
def_id: LocalDefId,
tcx: TyCtxt<'_>,
effective_visibilities: &EffectiveVisibilities,
) -> Self {
let mut find = FindMin { tcx, effective_visibilities, min: Self::MAX };
find.visit(tcx.type_of(def_id));
if let Some(trait_ref) = tcx.impl_trait_ref(def_id) {
find.visit_trait(trait_ref.subst_identity());
}
find.min
}
}
impl VisibilityLike for ty::Visibility {
const MAX: Self = ty::Visibility::Public;
fn new_min(find: &FindMin<'_, '_, Self>, def_id: LocalDefId) -> Self {
min(find.tcx.local_visibility(def_id), find.min, find.tcx)
}
}
impl VisibilityLike for Option {
const MAX: Self = Some(Level::Direct);
// Type inference is very smart sometimes.
// It can make an impl reachable even some components of its type or trait are unreachable.
// E.g. methods of `impl ReachableTrait for ReachableTy { ... }`
// can be usable from other crates (#57264). So we skip substs when calculating reachability
// and consider an impl reachable if its "shallow" type and trait are reachable.
//
// The assumption we make here is that type-inference won't let you use an impl without knowing
// both "shallow" version of its self type and "shallow" version of its trait if it exists
// (which require reaching the `DefId`s in them).
const SHALLOW: bool = true;
fn new_min(find: &FindMin<'_, '_, Self>, def_id: LocalDefId) -> Self {
cmp::min(find.effective_visibilities.public_at_level(def_id), find.min)
}
}
////////////////////////////////////////////////////////////////////////////////
/// The embargo visitor, used to determine the exports of the AST.
////////////////////////////////////////////////////////////////////////////////
struct EmbargoVisitor<'tcx> {
tcx: TyCtxt<'tcx>,
/// Effective visibilities for reachable nodes.
effective_visibilities: EffectiveVisibilities,
/// A set of pairs corresponding to modules, where the first module is
/// reachable via a macro that's defined in the second module. This cannot
/// be represented as reachable because it can't handle the following case:
///
/// pub mod n { // Should be `Public`
/// pub(crate) mod p { // Should *not* be accessible
/// pub fn f() -> i32 { 12 } // Must be `Reachable`
/// }
/// }
/// pub macro m() {
/// n::p::f()
/// }
macro_reachable: FxHashSet<(LocalDefId, LocalDefId)>,
/// Previous visibility level; `None` means unreachable.
prev_level: Option,
/// Has something changed in the level map?
changed: bool,
}
struct ReachEverythingInTheInterfaceVisitor<'a, 'tcx> {
level: Option,
item_def_id: LocalDefId,
ev: &'a mut EmbargoVisitor<'tcx>,
}
impl<'tcx> EmbargoVisitor<'tcx> {
fn get(&self, def_id: LocalDefId) -> Option {
self.effective_visibilities.public_at_level(def_id)
}
/// Updates node level and returns the updated level.
fn update(&mut self, def_id: LocalDefId, level: Option) -> Option {
let old_level = self.get(def_id);
// Visibility levels can only grow.
if level > old_level {
self.effective_visibilities.set_public_at_level(
def_id,
|| ty::Visibility::Restricted(self.tcx.parent_module_from_def_id(def_id)),
level.unwrap(),
);
self.changed = true;
level
} else {
old_level
}
}
fn reach(
&mut self,
def_id: LocalDefId,
level: Option,
) -> ReachEverythingInTheInterfaceVisitor<'_, 'tcx> {
ReachEverythingInTheInterfaceVisitor {
level: cmp::min(level, Some(Level::Reachable)),
item_def_id: def_id,
ev: self,
}
}
// We have to make sure that the items that macros might reference
// are reachable, since they might be exported transitively.
fn update_reachability_from_macro(&mut self, local_def_id: LocalDefId, md: &MacroDef) {
// Non-opaque macros cannot make other items more accessible than they already are.
let hir_id = self.tcx.hir().local_def_id_to_hir_id(local_def_id);
let attrs = self.tcx.hir().attrs(hir_id);
if attr::find_transparency(attrs, md.macro_rules).0 != Transparency::Opaque {
return;
}
let macro_module_def_id = self.tcx.local_parent(local_def_id);
if self.tcx.opt_def_kind(macro_module_def_id) != Some(DefKind::Mod) {
// The macro's parent doesn't correspond to a `mod`, return early (#63164, #65252).
return;
}
if self.get(local_def_id).is_none() {
return;
}
// Since we are starting from an externally visible module,
// all the parents in the loop below are also guaranteed to be modules.
let mut module_def_id = macro_module_def_id;
loop {
let changed_reachability =
self.update_macro_reachable(module_def_id, macro_module_def_id);
if changed_reachability || module_def_id == CRATE_DEF_ID {
break;
}
module_def_id = self.tcx.local_parent(module_def_id);
}
}
/// Updates the item as being reachable through a macro defined in the given
/// module. Returns `true` if the level has changed.
fn update_macro_reachable(
&mut self,
module_def_id: LocalDefId,
defining_mod: LocalDefId,
) -> bool {
if self.macro_reachable.insert((module_def_id, defining_mod)) {
self.update_macro_reachable_mod(module_def_id, defining_mod);
true
} else {
false
}
}
fn update_macro_reachable_mod(&mut self, module_def_id: LocalDefId, defining_mod: LocalDefId) {
let module = self.tcx.hir().get_module(module_def_id).0;
for item_id in module.item_ids {
let def_kind = self.tcx.def_kind(item_id.owner_id);
let vis = self.tcx.local_visibility(item_id.owner_id.def_id);
self.update_macro_reachable_def(item_id.owner_id.def_id, def_kind, vis, defining_mod);
}
if let Some(exports) = self.tcx.module_reexports(module_def_id) {
for export in exports {
if export.vis.is_accessible_from(defining_mod, self.tcx) {
if let Res::Def(def_kind, def_id) = export.res {
if let Some(def_id) = def_id.as_local() {
let vis = self.tcx.local_visibility(def_id);
self.update_macro_reachable_def(def_id, def_kind, vis, defining_mod);
}
}
}
}
}
}
fn update_macro_reachable_def(
&mut self,
def_id: LocalDefId,
def_kind: DefKind,
vis: ty::Visibility,
module: LocalDefId,
) {
let level = Some(Level::Reachable);
if vis.is_public() {
self.update(def_id, level);
}
match def_kind {
// No type privacy, so can be directly marked as reachable.
DefKind::Const | DefKind::Static(_) | DefKind::TraitAlias | DefKind::TyAlias => {
if vis.is_accessible_from(module, self.tcx) {
self.update(def_id, level);
}
}
// Hygiene isn't really implemented for `macro_rules!` macros at the
// moment. Accordingly, marking them as reachable is unwise. `macro` macros
// have normal hygiene, so we can treat them like other items without type
// privacy and mark them reachable.
DefKind::Macro(_) => {
let item = self.tcx.hir().expect_item(def_id);
if let hir::ItemKind::Macro(MacroDef { macro_rules: false, .. }, _) = item.kind {
if vis.is_accessible_from(module, self.tcx) {
self.update(def_id, level);
}
}
}
// We can't use a module name as the final segment of a path, except
// in use statements. Since re-export checking doesn't consider
// hygiene these don't need to be marked reachable. The contents of
// the module, however may be reachable.
DefKind::Mod => {
if vis.is_accessible_from(module, self.tcx) {
self.update_macro_reachable(def_id, module);
}
}
DefKind::Struct | DefKind::Union => {
// While structs and unions have type privacy, their fields do not.
if vis.is_public() {
let item = self.tcx.hir().expect_item(def_id);
if let hir::ItemKind::Struct(ref struct_def, _)
| hir::ItemKind::Union(ref struct_def, _) = item.kind
{
for field in struct_def.fields() {
let field_vis = self.tcx.local_visibility(field.def_id);
if field_vis.is_accessible_from(module, self.tcx) {
self.reach(field.def_id, level).ty();
}
}
} else {
bug!("item {:?} with DefKind {:?}", item, def_kind);
}
}
}
// These have type privacy, so are not reachable unless they're
// public, or are not namespaced at all.
DefKind::AssocConst
| DefKind::AssocTy
| DefKind::ConstParam
| DefKind::Ctor(_, _)
| DefKind::Enum
| DefKind::ForeignTy
| DefKind::Fn
| DefKind::OpaqueTy
| DefKind::ImplTraitPlaceholder
| DefKind::AssocFn
| DefKind::Trait
| DefKind::TyParam
| DefKind::Variant
| DefKind::LifetimeParam
| DefKind::ExternCrate
| DefKind::Use
| DefKind::ForeignMod
| DefKind::AnonConst
| DefKind::InlineConst
| DefKind::Field
| DefKind::GlobalAsm
| DefKind::Impl
| DefKind::Closure
| DefKind::Generator => (),
}
}
}
impl<'tcx> Visitor<'tcx> for EmbargoVisitor<'tcx> {
type NestedFilter = nested_filter::All;
/// We want to visit items in the context of their containing
/// module and so forth, so supply a crate for doing a deep walk.
fn nested_visit_map(&mut self) -> Self::Map {
self.tcx.hir()
}
fn visit_item(&mut self, item: &'tcx hir::Item<'tcx>) {
let item_level = match item.kind {
hir::ItemKind::Impl { .. } => {
let impl_level = Option::::of_impl(
item.owner_id.def_id,
self.tcx,
&self.effective_visibilities,
);
self.update(item.owner_id.def_id, impl_level)
}
_ => self.get(item.owner_id.def_id),
};
// Update levels of nested things.
match item.kind {
hir::ItemKind::Enum(ref def, _) => {
for variant in def.variants {
let variant_level = self.update(variant.def_id, item_level);
if let Some(ctor_def_id) = variant.data.ctor_def_id() {
self.update(ctor_def_id, item_level);
}
for field in variant.data.fields() {
self.update(field.def_id, variant_level);
}
}
}
hir::ItemKind::Impl(ref impl_) => {
for impl_item_ref in impl_.items {
if impl_.of_trait.is_some()
|| self.tcx.visibility(impl_item_ref.id.owner_id).is_public()
{
self.update(impl_item_ref.id.owner_id.def_id, item_level);
}
}
}
hir::ItemKind::Trait(.., trait_item_refs) => {
for trait_item_ref in trait_item_refs {
self.update(trait_item_ref.id.owner_id.def_id, item_level);
}
}
hir::ItemKind::Struct(ref def, _) | hir::ItemKind::Union(ref def, _) => {
if let Some(ctor_def_id) = def.ctor_def_id() {
self.update(ctor_def_id, item_level);
}
for field in def.fields() {
let vis = self.tcx.visibility(field.def_id);
if vis.is_public() {
self.update(field.def_id, item_level);
}
}
}
hir::ItemKind::Macro(ref macro_def, _) => {
self.update_reachability_from_macro(item.owner_id.def_id, macro_def);
}
hir::ItemKind::ForeignMod { items, .. } => {
for foreign_item in items {
if self.tcx.visibility(foreign_item.id.owner_id).is_public() {
self.update(foreign_item.id.owner_id.def_id, item_level);
}
}
}
hir::ItemKind::OpaqueTy(..)
| hir::ItemKind::Use(..)
| hir::ItemKind::Static(..)
| hir::ItemKind::Const(..)
| hir::ItemKind::GlobalAsm(..)
| hir::ItemKind::TyAlias(..)
| hir::ItemKind::Mod(..)
| hir::ItemKind::TraitAlias(..)
| hir::ItemKind::Fn(..)
| hir::ItemKind::ExternCrate(..) => {}
}
// Mark all items in interfaces of reachable items as reachable.
match item.kind {
// The interface is empty.
hir::ItemKind::Macro(..) | hir::ItemKind::ExternCrate(..) => {}
// All nested items are checked by `visit_item`.
hir::ItemKind::Mod(..) => {}
// Handled in `rustc_resolve`.
hir::ItemKind::Use(..) => {}
// The interface is empty.
hir::ItemKind::GlobalAsm(..) => {}
hir::ItemKind::OpaqueTy(ref opaque) => {
// HACK(jynelson): trying to infer the type of `impl trait` breaks `async-std` (and `pub async fn` in general)
// Since rustdoc never needs to do codegen and doesn't care about link-time reachability,
// mark this as unreachable.
// See https://github.com/rust-lang/rust/issues/75100
if !opaque.in_trait && !self.tcx.sess.opts.actually_rustdoc {
// FIXME: This is some serious pessimization intended to workaround deficiencies
// in the reachability pass (`middle/reachable.rs`). Types are marked as link-time
// reachable if they are returned via `impl Trait`, even from private functions.
let exist_level = cmp::max(item_level, Some(Level::ReachableThroughImplTrait));
self.reach(item.owner_id.def_id, exist_level).generics().predicates().ty();
}
}
// Visit everything.
hir::ItemKind::Const(..)
| hir::ItemKind::Static(..)
| hir::ItemKind::Fn(..)
| hir::ItemKind::TyAlias(..) => {
if item_level.is_some() {
self.reach(item.owner_id.def_id, item_level).generics().predicates().ty();
}
}
hir::ItemKind::Trait(.., trait_item_refs) => {
if item_level.is_some() {
self.reach(item.owner_id.def_id, item_level).generics().predicates();
for trait_item_ref in trait_item_refs {
let tcx = self.tcx;
let mut reach = self.reach(trait_item_ref.id.owner_id.def_id, item_level);
reach.generics().predicates();
if trait_item_ref.kind == AssocItemKind::Type
&& !tcx.impl_defaultness(trait_item_ref.id.owner_id).has_value()
{
// No type to visit.
} else {
reach.ty();
}
}
}
}
hir::ItemKind::TraitAlias(..) => {
if item_level.is_some() {
self.reach(item.owner_id.def_id, item_level).generics().predicates();
}
}
// Visit everything except for private impl items.
hir::ItemKind::Impl(ref impl_) => {
if item_level.is_some() {
self.reach(item.owner_id.def_id, item_level)
.generics()
.predicates()
.ty()
.trait_ref();
for impl_item_ref in impl_.items {
let impl_item_level = self.get(impl_item_ref.id.owner_id.def_id);
if impl_item_level.is_some() {
self.reach(impl_item_ref.id.owner_id.def_id, impl_item_level)
.generics()
.predicates()
.ty();
}
}
}
}
// Visit everything, but enum variants have their own levels.
hir::ItemKind::Enum(ref def, _) => {
if item_level.is_some() {
self.reach(item.owner_id.def_id, item_level).generics().predicates();
}
for variant in def.variants {
let variant_level = self.get(variant.def_id);
if variant_level.is_some() {
for field in variant.data.fields() {
self.reach(field.def_id, variant_level).ty();
}
// Corner case: if the variant is reachable, but its
// enum is not, make the enum reachable as well.
self.reach(item.owner_id.def_id, variant_level).ty();
}
if let Some(ctor_def_id) = variant.data.ctor_def_id() {
let ctor_level = self.get(ctor_def_id);
if ctor_level.is_some() {
self.reach(item.owner_id.def_id, ctor_level).ty();
}
}
}
}
// Visit everything, but foreign items have their own levels.
hir::ItemKind::ForeignMod { items, .. } => {
for foreign_item in items {
let foreign_item_level = self.get(foreign_item.id.owner_id.def_id);
if foreign_item_level.is_some() {
self.reach(foreign_item.id.owner_id.def_id, foreign_item_level)
.generics()
.predicates()
.ty();
}
}
}
// Visit everything except for private fields.
hir::ItemKind::Struct(ref struct_def, _) | hir::ItemKind::Union(ref struct_def, _) => {
if item_level.is_some() {
self.reach(item.owner_id.def_id, item_level).generics().predicates();
for field in struct_def.fields() {
let field_level = self.get(field.def_id);
if field_level.is_some() {
self.reach(field.def_id, field_level).ty();
}
}
}
if let Some(ctor_def_id) = struct_def.ctor_def_id() {
let ctor_level = self.get(ctor_def_id);
if ctor_level.is_some() {
self.reach(item.owner_id.def_id, ctor_level).ty();
}
}
}
}
let orig_level = mem::replace(&mut self.prev_level, item_level);
intravisit::walk_item(self, item);
self.prev_level = orig_level;
}
fn visit_block(&mut self, b: &'tcx hir::Block<'tcx>) {
// Blocks can have public items, for example impls, but they always
// start as completely private regardless of publicity of a function,
// constant, type, field, etc., in which this block resides.
let orig_level = mem::replace(&mut self.prev_level, None);
intravisit::walk_block(self, b);
self.prev_level = orig_level;
}
}
impl ReachEverythingInTheInterfaceVisitor<'_, '_> {
fn generics(&mut self) -> &mut Self {
for param in &self.ev.tcx.generics_of(self.item_def_id).params {
match param.kind {
GenericParamDefKind::Lifetime => {}
GenericParamDefKind::Type { has_default, .. } => {
if has_default {
self.visit(self.ev.tcx.type_of(param.def_id));
}
}
GenericParamDefKind::Const { has_default } => {
self.visit(self.ev.tcx.type_of(param.def_id));
if has_default {
self.visit(self.ev.tcx.const_param_default(param.def_id).subst_identity());
}
}
}
}
self
}
fn predicates(&mut self) -> &mut Self {
self.visit_predicates(self.ev.tcx.predicates_of(self.item_def_id));
self
}
fn ty(&mut self) -> &mut Self {
self.visit(self.ev.tcx.type_of(self.item_def_id));
self
}
fn trait_ref(&mut self) -> &mut Self {
if let Some(trait_ref) = self.ev.tcx.impl_trait_ref(self.item_def_id) {
self.visit_trait(trait_ref.subst_identity());
}
self
}
}
impl<'tcx> DefIdVisitor<'tcx> for ReachEverythingInTheInterfaceVisitor<'_, 'tcx> {
fn tcx(&self) -> TyCtxt<'tcx> {
self.ev.tcx
}
fn visit_def_id(
&mut self,
def_id: DefId,
_kind: &str,
_descr: &dyn fmt::Display,
) -> ControlFlow {
if let Some(def_id) = def_id.as_local() {
if let (ty::Visibility::Public, _) | (_, Some(Level::ReachableThroughImplTrait)) =
(self.tcx().visibility(def_id.to_def_id()), self.level)
{
self.ev.update(def_id, self.level);
}
}
ControlFlow::Continue(())
}
}
////////////////////////////////////////////////////////////////////////////////
/// Visitor, used for EffectiveVisibilities table checking
////////////////////////////////////////////////////////////////////////////////
pub struct TestReachabilityVisitor<'tcx, 'a> {
tcx: TyCtxt<'tcx>,
effective_visibilities: &'a EffectiveVisibilities,
}
impl<'tcx, 'a> TestReachabilityVisitor<'tcx, 'a> {
fn effective_visibility_diagnostic(&mut self, def_id: LocalDefId) {
if self.tcx.has_attr(def_id.to_def_id(), sym::rustc_effective_visibility) {
let mut error_msg = String::new();
let span = self.tcx.def_span(def_id.to_def_id());
if let Some(effective_vis) = self.effective_visibilities.effective_vis(def_id) {
for level in Level::all_levels() {
let vis_str = match effective_vis.at_level(level) {
ty::Visibility::Restricted(restricted_id) => {
if restricted_id.is_top_level_module() {
"pub(crate)".to_string()
} else if *restricted_id == self.tcx.parent_module_from_def_id(def_id) {
"pub(self)".to_string()
} else {
format!("pub({})", self.tcx.item_name(restricted_id.to_def_id()))
}
}
ty::Visibility::Public => "pub".to_string(),
};
if level != Level::Direct {
error_msg.push_str(", ");
}
error_msg.push_str(&format!("{level:?}: {vis_str}"));
}
} else {
error_msg.push_str("not in the table");
}
self.tcx.sess.emit_err(ReportEffectiveVisibility { span, descr: error_msg });
}
}
}
impl<'tcx, 'a> Visitor<'tcx> for TestReachabilityVisitor<'tcx, 'a> {
fn visit_item(&mut self, item: &'tcx hir::Item<'tcx>) {
self.effective_visibility_diagnostic(item.owner_id.def_id);
match item.kind {
hir::ItemKind::Enum(ref def, _) => {
for variant in def.variants.iter() {
self.effective_visibility_diagnostic(variant.def_id);
if let Some(ctor_def_id) = variant.data.ctor_def_id() {
self.effective_visibility_diagnostic(ctor_def_id);
}
for field in variant.data.fields() {
self.effective_visibility_diagnostic(field.def_id);
}
}
}
hir::ItemKind::Struct(ref def, _) | hir::ItemKind::Union(ref def, _) => {
if let Some(ctor_def_id) = def.ctor_def_id() {
self.effective_visibility_diagnostic(ctor_def_id);
}
for field in def.fields() {
self.effective_visibility_diagnostic(field.def_id);
}
}
_ => {}
}
}
fn visit_trait_item(&mut self, item: &'tcx hir::TraitItem<'tcx>) {
self.effective_visibility_diagnostic(item.owner_id.def_id);
}
fn visit_impl_item(&mut self, item: &'tcx hir::ImplItem<'tcx>) {
self.effective_visibility_diagnostic(item.owner_id.def_id);
}
fn visit_foreign_item(&mut self, item: &'tcx hir::ForeignItem<'tcx>) {
self.effective_visibility_diagnostic(item.owner_id.def_id);
}
}
//////////////////////////////////////////////////////////////////////////////////////
/// Name privacy visitor, checks privacy and reports violations.
/// Most of name privacy checks are performed during the main resolution phase,
/// or later in type checking when field accesses and associated items are resolved.
/// This pass performs remaining checks for fields in struct expressions and patterns.
//////////////////////////////////////////////////////////////////////////////////////
struct NamePrivacyVisitor<'tcx> {
tcx: TyCtxt<'tcx>,
maybe_typeck_results: Option<&'tcx ty::TypeckResults<'tcx>>,
current_item: LocalDefId,
}
impl<'tcx> NamePrivacyVisitor<'tcx> {
/// Gets the type-checking results for the current body.
/// As this will ICE if called outside bodies, only call when working with
/// `Expr` or `Pat` nodes (they are guaranteed to be found only in bodies).
#[track_caller]
fn typeck_results(&self) -> &'tcx ty::TypeckResults<'tcx> {
self.maybe_typeck_results
.expect("`NamePrivacyVisitor::typeck_results` called outside of body")
}
// Checks that a field in a struct constructor (expression or pattern) is accessible.
fn check_field(
&mut self,
use_ctxt: Span, // syntax context of the field name at the use site
span: Span, // span of the field pattern, e.g., `x: 0`
def: ty::AdtDef<'tcx>, // definition of the struct or enum
field: &'tcx ty::FieldDef,
in_update_syntax: bool,
) {
if def.is_enum() {
return;
}
// definition of the field
let ident = Ident::new(kw::Empty, use_ctxt);
let hir_id = self.tcx.hir().local_def_id_to_hir_id(self.current_item);
let def_id = self.tcx.adjust_ident_and_get_scope(ident, def.did(), hir_id).1;
if !field.vis.is_accessible_from(def_id, self.tcx) {
self.tcx.sess.emit_err(FieldIsPrivate {
span,
field_name: field.name,
variant_descr: def.variant_descr(),
def_path_str: self.tcx.def_path_str(def.did()),
label: if in_update_syntax {
FieldIsPrivateLabel::IsUpdateSyntax { span, field_name: field.name }
} else {
FieldIsPrivateLabel::Other { span }
},
});
}
}
}
impl<'tcx> Visitor<'tcx> for NamePrivacyVisitor<'tcx> {
type NestedFilter = nested_filter::All;
/// We want to visit items in the context of their containing
/// module and so forth, so supply a crate for doing a deep walk.
fn nested_visit_map(&mut self) -> Self::Map {
self.tcx.hir()
}
fn visit_mod(&mut self, _m: &'tcx hir::Mod<'tcx>, _s: Span, _n: hir::HirId) {
// Don't visit nested modules, since we run a separate visitor walk
// for each module in `effective_visibilities`
}
fn visit_nested_body(&mut self, body: hir::BodyId) {
let old_maybe_typeck_results =
self.maybe_typeck_results.replace(self.tcx.typeck_body(body));
let body = self.tcx.hir().body(body);
self.visit_body(body);
self.maybe_typeck_results = old_maybe_typeck_results;
}
fn visit_item(&mut self, item: &'tcx hir::Item<'tcx>) {
let orig_current_item = mem::replace(&mut self.current_item, item.owner_id.def_id);
intravisit::walk_item(self, item);
self.current_item = orig_current_item;
}
fn visit_expr(&mut self, expr: &'tcx hir::Expr<'tcx>) {
if let hir::ExprKind::Struct(qpath, fields, ref base) = expr.kind {
let res = self.typeck_results().qpath_res(qpath, expr.hir_id);
let adt = self.typeck_results().expr_ty(expr).ty_adt_def().unwrap();
let variant = adt.variant_of_res(res);
if let Some(base) = *base {
// If the expression uses FRU we need to make sure all the unmentioned fields
// are checked for privacy (RFC 736). Rather than computing the set of
// unmentioned fields, just check them all.
for (vf_index, variant_field) in variant.fields.iter().enumerate() {
let field = fields
.iter()
.find(|f| self.typeck_results().field_index(f.hir_id) == vf_index);
let (use_ctxt, span) = match field {
Some(field) => (field.ident.span, field.span),
None => (base.span, base.span),
};
self.check_field(use_ctxt, span, adt, variant_field, true);
}
} else {
for field in fields {
let use_ctxt = field.ident.span;
let index = self.typeck_results().field_index(field.hir_id);
self.check_field(use_ctxt, field.span, adt, &variant.fields[index], false);
}
}
}
intravisit::walk_expr(self, expr);
}
fn visit_pat(&mut self, pat: &'tcx hir::Pat<'tcx>) {
if let PatKind::Struct(ref qpath, fields, _) = pat.kind {
let res = self.typeck_results().qpath_res(qpath, pat.hir_id);
let adt = self.typeck_results().pat_ty(pat).ty_adt_def().unwrap();
let variant = adt.variant_of_res(res);
for field in fields {
let use_ctxt = field.ident.span;
let index = self.typeck_results().field_index(field.hir_id);
self.check_field(use_ctxt, field.span, adt, &variant.fields[index], false);
}
}
intravisit::walk_pat(self, pat);
}
}
////////////////////////////////////////////////////////////////////////////////////////////
/// Type privacy visitor, checks types for privacy and reports violations.
/// Both explicitly written types and inferred types of expressions and patterns are checked.
/// Checks are performed on "semantic" types regardless of names and their hygiene.
////////////////////////////////////////////////////////////////////////////////////////////
struct TypePrivacyVisitor<'tcx> {
tcx: TyCtxt<'tcx>,
maybe_typeck_results: Option<&'tcx ty::TypeckResults<'tcx>>,
current_item: LocalDefId,
span: Span,
}
impl<'tcx> TypePrivacyVisitor<'tcx> {
/// Gets the type-checking results for the current body.
/// As this will ICE if called outside bodies, only call when working with
/// `Expr` or `Pat` nodes (they are guaranteed to be found only in bodies).
#[track_caller]
fn typeck_results(&self) -> &'tcx ty::TypeckResults<'tcx> {
self.maybe_typeck_results
.expect("`TypePrivacyVisitor::typeck_results` called outside of body")
}
fn item_is_accessible(&self, did: DefId) -> bool {
self.tcx.visibility(did).is_accessible_from(self.current_item, self.tcx)
}
// Take node-id of an expression or pattern and check its type for privacy.
fn check_expr_pat_type(&mut self, id: hir::HirId, span: Span) -> bool {
self.span = span;
let typeck_results = self.typeck_results();
let result: ControlFlow<()> = try {
self.visit(typeck_results.node_type(id))?;
self.visit(typeck_results.node_substs(id))?;
if let Some(adjustments) = typeck_results.adjustments().get(id) {
adjustments.iter().try_for_each(|adjustment| self.visit(adjustment.target))?;
}
};
result.is_break()
}
fn check_def_id(&mut self, def_id: DefId, kind: &str, descr: &dyn fmt::Display) -> bool {
let is_error = !self.item_is_accessible(def_id);
if is_error {
self.tcx.sess.emit_err(ItemIsPrivate { span: self.span, kind, descr: descr.into() });
}
is_error
}
}
impl<'tcx> Visitor<'tcx> for TypePrivacyVisitor<'tcx> {
type NestedFilter = nested_filter::All;
/// We want to visit items in the context of their containing
/// module and so forth, so supply a crate for doing a deep walk.
fn nested_visit_map(&mut self) -> Self::Map {
self.tcx.hir()
}
fn visit_mod(&mut self, _m: &'tcx hir::Mod<'tcx>, _s: Span, _n: hir::HirId) {
// Don't visit nested modules, since we run a separate visitor walk
// for each module in `effective_visibilities`
}
fn visit_nested_body(&mut self, body: hir::BodyId) {
let old_maybe_typeck_results =
self.maybe_typeck_results.replace(self.tcx.typeck_body(body));
let body = self.tcx.hir().body(body);
self.visit_body(body);
self.maybe_typeck_results = old_maybe_typeck_results;
}
fn visit_generic_arg(&mut self, generic_arg: &'tcx hir::GenericArg<'tcx>) {
match generic_arg {
hir::GenericArg::Type(t) => self.visit_ty(t),
hir::GenericArg::Infer(inf) => self.visit_infer(inf),
hir::GenericArg::Lifetime(_) | hir::GenericArg::Const(_) => {}
}
}
fn visit_ty(&mut self, hir_ty: &'tcx hir::Ty<'tcx>) {
self.span = hir_ty.span;
if let Some(typeck_results) = self.maybe_typeck_results {
// Types in bodies.
if self.visit(typeck_results.node_type(hir_ty.hir_id)).is_break() {
return;
}
} else {
// Types in signatures.
// FIXME: This is very ineffective. Ideally each HIR type should be converted
// into a semantic type only once and the result should be cached somehow.
if self.visit(rustc_hir_analysis::hir_ty_to_ty(self.tcx, hir_ty)).is_break() {
return;
}
}
intravisit::walk_ty(self, hir_ty);
}
fn visit_infer(&mut self, inf: &'tcx hir::InferArg) {
self.span = inf.span;
if let Some(typeck_results) = self.maybe_typeck_results {
if let Some(ty) = typeck_results.node_type_opt(inf.hir_id) {
if self.visit(ty).is_break() {
return;
}
} else {
// We don't do anything for const infers here.
}
} else {
bug!("visit_infer without typeck_results");
}
intravisit::walk_inf(self, inf);
}
fn visit_trait_ref(&mut self, trait_ref: &'tcx hir::TraitRef<'tcx>) {
self.span = trait_ref.path.span;
if self.maybe_typeck_results.is_none() {
// Avoid calling `hir_trait_to_predicates` in bodies, it will ICE.
// The traits' privacy in bodies is already checked as a part of trait object types.
let bounds = rustc_hir_analysis::hir_trait_to_predicates(
self.tcx,
trait_ref,
// NOTE: This isn't really right, but the actual type doesn't matter here. It's
// just required by `ty::TraitRef`.
self.tcx.types.never,
);
for (pred, _) in bounds.predicates() {
match pred.kind().skip_binder() {
ty::PredicateKind::Clause(ty::Clause::Trait(trait_predicate)) => {
if self.visit_trait(trait_predicate.trait_ref).is_break() {
return;
}
}
ty::PredicateKind::Clause(ty::Clause::Projection(proj_predicate)) => {
let term = self.visit(proj_predicate.term);
if term.is_break()
|| self.visit_projection_ty(proj_predicate.projection_ty).is_break()
{
return;
}
}
_ => {}
}
}
}
intravisit::walk_trait_ref(self, trait_ref);
}
// Check types of expressions
fn visit_expr(&mut self, expr: &'tcx hir::Expr<'tcx>) {
if self.check_expr_pat_type(expr.hir_id, expr.span) {
// Do not check nested expressions if the error already happened.
return;
}
match expr.kind {
hir::ExprKind::Assign(_, rhs, _) | hir::ExprKind::Match(rhs, ..) => {
// Do not report duplicate errors for `x = y` and `match x { ... }`.
if self.check_expr_pat_type(rhs.hir_id, rhs.span) {
return;
}
}
hir::ExprKind::MethodCall(segment, ..) => {
// Method calls have to be checked specially.
self.span = segment.ident.span;
if let Some(def_id) = self.typeck_results().type_dependent_def_id(expr.hir_id) {
if self.visit(self.tcx.type_of(def_id)).is_break() {
return;
}
} else {
self.tcx
.sess
.delay_span_bug(expr.span, "no type-dependent def for method call");
}
}
_ => {}
}
intravisit::walk_expr(self, expr);
}
// Prohibit access to associated items with insufficient nominal visibility.
//
// Additionally, until better reachability analysis for macros 2.0 is available,
// we prohibit access to private statics from other crates, this allows to give
// more code internal visibility at link time. (Access to private functions
// is already prohibited by type privacy for function types.)
fn visit_qpath(&mut self, qpath: &'tcx hir::QPath<'tcx>, id: hir::HirId, span: Span) {
let def = match qpath {
hir::QPath::Resolved(_, path) => match path.res {
Res::Def(kind, def_id) => Some((kind, def_id)),
_ => None,
},
hir::QPath::TypeRelative(..) | hir::QPath::LangItem(..) => self
.maybe_typeck_results
.and_then(|typeck_results| typeck_results.type_dependent_def(id)),
};
let def = def.filter(|(kind, _)| {
matches!(
kind,
DefKind::AssocFn | DefKind::AssocConst | DefKind::AssocTy | DefKind::Static(_)
)
});
if let Some((kind, def_id)) = def {
let is_local_static =
if let DefKind::Static(_) = kind { def_id.is_local() } else { false };
if !self.item_is_accessible(def_id) && !is_local_static {
let name = match *qpath {
hir::QPath::LangItem(it, ..) => {
self.tcx.lang_items().get(it).map(|did| self.tcx.def_path_str(did))
}
hir::QPath::Resolved(_, path) => Some(self.tcx.def_path_str(path.res.def_id())),
hir::QPath::TypeRelative(_, segment) => Some(segment.ident.to_string()),
};
let kind = kind.descr(def_id);
let sess = self.tcx.sess;
let _ = match name {
Some(name) => {
sess.emit_err(ItemIsPrivate { span, kind, descr: (&name).into() })
}
None => sess.emit_err(UnnamedItemIsPrivate { span, kind }),
};
return;
}
}
intravisit::walk_qpath(self, qpath, id);
}
// Check types of patterns.
fn visit_pat(&mut self, pattern: &'tcx hir::Pat<'tcx>) {
if self.check_expr_pat_type(pattern.hir_id, pattern.span) {
// Do not check nested patterns if the error already happened.
return;
}
intravisit::walk_pat(self, pattern);
}
fn visit_local(&mut self, local: &'tcx hir::Local<'tcx>) {
if let Some(init) = local.init {
if self.check_expr_pat_type(init.hir_id, init.span) {
// Do not report duplicate errors for `let x = y`.
return;
}
}
intravisit::walk_local(self, local);
}
// Check types in item interfaces.
fn visit_item(&mut self, item: &'tcx hir::Item<'tcx>) {
let orig_current_item = mem::replace(&mut self.current_item, item.owner_id.def_id);
let old_maybe_typeck_results = self.maybe_typeck_results.take();
intravisit::walk_item(self, item);
self.maybe_typeck_results = old_maybe_typeck_results;
self.current_item = orig_current_item;
}
}
impl<'tcx> DefIdVisitor<'tcx> for TypePrivacyVisitor<'tcx> {
fn tcx(&self) -> TyCtxt<'tcx> {
self.tcx
}
fn visit_def_id(
&mut self,
def_id: DefId,
kind: &str,
descr: &dyn fmt::Display,
) -> ControlFlow {
if self.check_def_id(def_id, kind, descr) {
ControlFlow::Break(())
} else {
ControlFlow::Continue(())
}
}
}
///////////////////////////////////////////////////////////////////////////////
/// Obsolete visitors for checking for private items in public interfaces.
/// These visitors are supposed to be kept in frozen state and produce an
/// "old error node set". For backward compatibility the new visitor reports
/// warnings instead of hard errors when the erroneous node is not in this old set.
///////////////////////////////////////////////////////////////////////////////
struct ObsoleteVisiblePrivateTypesVisitor<'a, 'tcx> {
tcx: TyCtxt<'tcx>,
effective_visibilities: &'a EffectiveVisibilities,
in_variant: bool,
// Set of errors produced by this obsolete visitor.
old_error_set: HirIdSet,
}
struct ObsoleteCheckTypeForPrivatenessVisitor<'a, 'b, 'tcx> {
inner: &'a ObsoleteVisiblePrivateTypesVisitor<'b, 'tcx>,
/// Whether the type refers to private types.
contains_private: bool,
/// Whether we've recurred at all (i.e., if we're pointing at the
/// first type on which `visit_ty` was called).
at_outer_type: bool,
/// Whether that first type is a public path.
outer_type_is_public_path: bool,
}
impl<'a, 'tcx> ObsoleteVisiblePrivateTypesVisitor<'a, 'tcx> {
fn path_is_private_type(&self, path: &hir::Path<'_>) -> bool {
let did = match path.res {
Res::PrimTy(..) | Res::SelfTyParam { .. } | Res::SelfTyAlias { .. } | Res::Err => {
return false;
}
res => res.def_id(),
};
// A path can only be private if:
// it's in this crate...
if let Some(did) = did.as_local() {
// .. and it corresponds to a private type in the AST (this returns
// `None` for type parameters).
match self.tcx.hir().find(self.tcx.hir().local_def_id_to_hir_id(did)) {
Some(Node::Item(_)) => !self.tcx.visibility(did).is_public(),
Some(_) | None => false,
}
} else {
false
}
}
fn trait_is_public(&self, trait_id: LocalDefId) -> bool {
// FIXME: this would preferably be using `exported_items`, but all
// traits are exported currently (see `EmbargoVisitor.exported_trait`).
self.effective_visibilities.is_directly_public(trait_id)
}
fn check_generic_bound(&mut self, bound: &hir::GenericBound<'_>) {
if let hir::GenericBound::Trait(ref trait_ref, _) = *bound {
if self.path_is_private_type(trait_ref.trait_ref.path) {
self.old_error_set.insert(trait_ref.trait_ref.hir_ref_id);
}
}
}
fn item_is_public(&self, def_id: LocalDefId) -> bool {
self.effective_visibilities.is_reachable(def_id) || self.tcx.visibility(def_id).is_public()
}
}
impl<'a, 'b, 'tcx, 'v> Visitor<'v> for ObsoleteCheckTypeForPrivatenessVisitor<'a, 'b, 'tcx> {
fn visit_generic_arg(&mut self, generic_arg: &'v hir::GenericArg<'v>) {
match generic_arg {
hir::GenericArg::Type(t) => self.visit_ty(t),
hir::GenericArg::Infer(inf) => self.visit_ty(&inf.to_ty()),
hir::GenericArg::Lifetime(_) | hir::GenericArg::Const(_) => {}
}
}
fn visit_ty(&mut self, ty: &hir::Ty<'_>) {
if let hir::TyKind::Path(hir::QPath::Resolved(_, path)) = ty.kind {
if self.inner.path_is_private_type(path) {
self.contains_private = true;
// Found what we're looking for, so let's stop working.
return;
}
}
if let hir::TyKind::Path(_) = ty.kind {
if self.at_outer_type {
self.outer_type_is_public_path = true;
}
}
self.at_outer_type = false;
intravisit::walk_ty(self, ty)
}
// Don't want to recurse into `[, .. expr]`.
fn visit_expr(&mut self, _: &hir::Expr<'_>) {}
}
impl<'a, 'tcx> Visitor<'tcx> for ObsoleteVisiblePrivateTypesVisitor<'a, 'tcx> {
type NestedFilter = nested_filter::All;
/// We want to visit items in the context of their containing
/// module and so forth, so supply a crate for doing a deep walk.
fn nested_visit_map(&mut self) -> Self::Map {
self.tcx.hir()
}
fn visit_item(&mut self, item: &'tcx hir::Item<'tcx>) {
match item.kind {
// Contents of a private mod can be re-exported, so we need
// to check internals.
hir::ItemKind::Mod(_) => {}
// An `extern {}` doesn't introduce a new privacy
// namespace (the contents have their own privacies).
hir::ItemKind::ForeignMod { .. } => {}
hir::ItemKind::Trait(.., bounds, _) => {
if !self.trait_is_public(item.owner_id.def_id) {
return;
}
for bound in bounds.iter() {
self.check_generic_bound(bound)
}
}
// Impls need some special handling to try to offer useful
// error messages without (too many) false positives
// (i.e., we could just return here to not check them at
// all, or some worse estimation of whether an impl is
// publicly visible).
hir::ItemKind::Impl(ref impl_) => {
// `impl [... for] Private` is never visible.
let self_contains_private;
// `impl [... for] Public<...>`, but not `impl [... for]
// Vec` or `(Public,)`, etc.
let self_is_public_path;
// Check the properties of the `Self` type:
{
let mut visitor = ObsoleteCheckTypeForPrivatenessVisitor {
inner: self,
contains_private: false,
at_outer_type: true,
outer_type_is_public_path: false,
};
visitor.visit_ty(impl_.self_ty);
self_contains_private = visitor.contains_private;
self_is_public_path = visitor.outer_type_is_public_path;
}
// Miscellaneous info about the impl:
// `true` iff this is `impl Private for ...`.
let not_private_trait = impl_.of_trait.as_ref().map_or(
true, // no trait counts as public trait
|tr| {
if let Some(def_id) = tr.path.res.def_id().as_local() {
self.trait_is_public(def_id)
} else {
true // external traits must be public
}
},
);
// `true` iff this is a trait impl or at least one method is public.
//
// `impl Public { $( fn ...() {} )* }` is not visible.
//
// This is required over just using the methods' privacy
// directly because we might have `impl> ...`,
// and we shouldn't warn about the generics if all the methods
// are private (because `T` won't be visible externally).
let trait_or_some_public_method = impl_.of_trait.is_some()
|| impl_.items.iter().any(|impl_item_ref| {
let impl_item = self.tcx.hir().impl_item(impl_item_ref.id);
match impl_item.kind {
hir::ImplItemKind::Const(..) | hir::ImplItemKind::Fn(..) => self
.effective_visibilities
.is_reachable(impl_item_ref.id.owner_id.def_id),
hir::ImplItemKind::Type(_) => false,
}
});
if !self_contains_private && not_private_trait && trait_or_some_public_method {
intravisit::walk_generics(self, &impl_.generics);
match impl_.of_trait {
None => {
for impl_item_ref in impl_.items {
// This is where we choose whether to walk down
// further into the impl to check its items. We
// should only walk into public items so that we
// don't erroneously report errors for private
// types in private items.
let impl_item = self.tcx.hir().impl_item(impl_item_ref.id);
match impl_item.kind {
hir::ImplItemKind::Const(..) | hir::ImplItemKind::Fn(..)
if self.item_is_public(impl_item.owner_id.def_id) =>
{
intravisit::walk_impl_item(self, impl_item)
}
hir::ImplItemKind::Type(..) => {
intravisit::walk_impl_item(self, impl_item)
}
_ => {}
}
}
}
Some(ref tr) => {
// Any private types in a trait impl fall into three
// categories.
// 1. mentioned in the trait definition
// 2. mentioned in the type params/generics
// 3. mentioned in the associated types of the impl
//
// Those in 1. can only occur if the trait is in
// this crate and will have been warned about on the
// trait definition (there's no need to warn twice
// so we don't check the methods).
//
// Those in 2. are warned via walk_generics and this
// call here.
intravisit::walk_path(self, tr.path);
// Those in 3. are warned with this call.
for impl_item_ref in impl_.items {
let impl_item = self.tcx.hir().impl_item(impl_item_ref.id);
if let hir::ImplItemKind::Type(ty) = impl_item.kind {
self.visit_ty(ty);
}
}
}
}
} else if impl_.of_trait.is_none() && self_is_public_path {
// `impl Public { ... }`. Any public static
// methods will be visible as `Public::foo`.
let mut found_pub_static = false;
for impl_item_ref in impl_.items {
if self
.effective_visibilities
.is_reachable(impl_item_ref.id.owner_id.def_id)
|| self.tcx.visibility(impl_item_ref.id.owner_id).is_public()
{
let impl_item = self.tcx.hir().impl_item(impl_item_ref.id);
match impl_item_ref.kind {
AssocItemKind::Const => {
found_pub_static = true;
intravisit::walk_impl_item(self, impl_item);
}
AssocItemKind::Fn { has_self: false } => {
found_pub_static = true;
intravisit::walk_impl_item(self, impl_item);
}
_ => {}
}
}
}
if found_pub_static {
intravisit::walk_generics(self, &impl_.generics)
}
}
return;
}
// `type ... = ...;` can contain private types, because
// we're introducing a new name.
hir::ItemKind::TyAlias(..) => return,
// Not at all public, so we don't care.
_ if !self.item_is_public(item.owner_id.def_id) => {
return;
}
_ => {}
}
// We've carefully constructed it so that if we're here, then
// any `visit_ty`'s will be called on things that are in
// public signatures, i.e., things that we're interested in for
// this visitor.
intravisit::walk_item(self, item);
}
fn visit_generics(&mut self, generics: &'tcx hir::Generics<'tcx>) {
for predicate in generics.predicates {
match predicate {
hir::WherePredicate::BoundPredicate(bound_pred) => {
for bound in bound_pred.bounds.iter() {
self.check_generic_bound(bound)
}
}
hir::WherePredicate::RegionPredicate(_) => {}
hir::WherePredicate::EqPredicate(eq_pred) => {
self.visit_ty(eq_pred.rhs_ty);
}
}
}
}
fn visit_foreign_item(&mut self, item: &'tcx hir::ForeignItem<'tcx>) {
if self.effective_visibilities.is_reachable(item.owner_id.def_id) {
intravisit::walk_foreign_item(self, item)
}
}
fn visit_ty(&mut self, t: &'tcx hir::Ty<'tcx>) {
if let hir::TyKind::Path(hir::QPath::Resolved(_, path)) = t.kind {
if self.path_is_private_type(path) {
self.old_error_set.insert(t.hir_id);
}
}
intravisit::walk_ty(self, t)
}
fn visit_variant(&mut self, v: &'tcx hir::Variant<'tcx>) {
if self.effective_visibilities.is_reachable(v.def_id) {
self.in_variant = true;
intravisit::walk_variant(self, v);
self.in_variant = false;
}
}
fn visit_field_def(&mut self, s: &'tcx hir::FieldDef<'tcx>) {
let vis = self.tcx.visibility(s.def_id);
if vis.is_public() || self.in_variant {
intravisit::walk_field_def(self, s);
}
}
// We don't need to introspect into these at all: an
// expression/block context can't possibly contain exported things.
// (Making them no-ops stops us from traversing the whole AST without
// having to be super careful about our `walk_...` calls above.)
fn visit_block(&mut self, _: &'tcx hir::Block<'tcx>) {}
fn visit_expr(&mut self, _: &'tcx hir::Expr<'tcx>) {}
}
///////////////////////////////////////////////////////////////////////////////
/// SearchInterfaceForPrivateItemsVisitor traverses an item's interface and
/// finds any private components in it.
/// PrivateItemsInPublicInterfacesVisitor ensures there are no private types
/// and traits in public interfaces.
///////////////////////////////////////////////////////////////////////////////
struct SearchInterfaceForPrivateItemsVisitor<'tcx> {
tcx: TyCtxt<'tcx>,
item_def_id: LocalDefId,
/// The visitor checks that each component type is at least this visible.
required_visibility: ty::Visibility,
has_old_errors: bool,
in_assoc_ty: bool,
}
impl SearchInterfaceForPrivateItemsVisitor<'_> {
fn generics(&mut self) -> &mut Self {
for param in &self.tcx.generics_of(self.item_def_id).params {
match param.kind {
GenericParamDefKind::Lifetime => {}
GenericParamDefKind::Type { has_default, .. } => {
if has_default {
self.visit(self.tcx.type_of(param.def_id));
}
}
// FIXME(generic_const_exprs): May want to look inside const here
GenericParamDefKind::Const { .. } => {
self.visit(self.tcx.type_of(param.def_id));
}
}
}
self
}
fn predicates(&mut self) -> &mut Self {
// N.B., we use `explicit_predicates_of` and not `predicates_of`
// because we don't want to report privacy errors due to where
// clauses that the compiler inferred. We only want to
// consider the ones that the user wrote. This is important
// for the inferred outlives rules; see
// `tests/ui/rfc-2093-infer-outlives/privacy.rs`.
self.visit_predicates(self.tcx.explicit_predicates_of(self.item_def_id));
self
}
fn bounds(&mut self) -> &mut Self {
self.visit_predicates(ty::GenericPredicates {
parent: None,
predicates: self.tcx.explicit_item_bounds(self.item_def_id),
});
self
}
fn ty(&mut self) -> &mut Self {
self.visit(self.tcx.type_of(self.item_def_id));
self
}
fn check_def_id(&mut self, def_id: DefId, kind: &str, descr: &dyn fmt::Display) -> bool {
if self.leaks_private_dep(def_id) {
self.tcx.emit_spanned_lint(
lint::builtin::EXPORTED_PRIVATE_DEPENDENCIES,
self.tcx.hir().local_def_id_to_hir_id(self.item_def_id),
self.tcx.def_span(self.item_def_id.to_def_id()),
FromPrivateDependencyInPublicInterface {
kind,
descr: descr.into(),
krate: self.tcx.crate_name(def_id.krate),
},
);
}
let Some(local_def_id) = def_id.as_local() else {
return false;
};
let vis = self.tcx.local_visibility(local_def_id);
if !vis.is_at_least(self.required_visibility, self.tcx) {
let hir_id = self.tcx.hir().local_def_id_to_hir_id(local_def_id);
let vis_descr = match vis {
ty::Visibility::Public => "public",
ty::Visibility::Restricted(vis_def_id) => {
if vis_def_id == self.tcx.parent_module(hir_id) {
"private"
} else if vis_def_id.is_top_level_module() {
"crate-private"
} else {
"restricted"
}
}
};
let span = self.tcx.def_span(self.item_def_id.to_def_id());
if self.has_old_errors
|| self.in_assoc_ty
|| self.tcx.resolutions(()).has_pub_restricted
{
let vis_span = self.tcx.def_span(def_id);
if kind == "trait" {
self.tcx.sess.emit_err(InPublicInterfaceTraits {
span,
vis_descr,
kind,
descr: descr.into(),
vis_span,
});
} else {
self.tcx.sess.emit_err(InPublicInterface {
span,
vis_descr,
kind,
descr: descr.into(),
vis_span,
});
}
} else {
self.tcx.emit_spanned_lint(
lint::builtin::PRIVATE_IN_PUBLIC,
hir_id,
span,
PrivateInPublicLint { vis_descr, kind, descr: descr.into() },
);
}
}
false
}
/// An item is 'leaked' from a private dependency if all
/// of the following are true:
/// 1. It's contained within a public type
/// 2. It comes from a private crate
fn leaks_private_dep(&self, item_id: DefId) -> bool {
let ret = self.required_visibility.is_public() && self.tcx.is_private_dep(item_id.krate);
debug!("leaks_private_dep(item_id={:?})={}", item_id, ret);
ret
}
}
impl<'tcx> DefIdVisitor<'tcx> for SearchInterfaceForPrivateItemsVisitor<'tcx> {
fn tcx(&self) -> TyCtxt<'tcx> {
self.tcx
}
fn visit_def_id(
&mut self,
def_id: DefId,
kind: &str,
descr: &dyn fmt::Display,
) -> ControlFlow {
if self.check_def_id(def_id, kind, descr) {
ControlFlow::Break(())
} else {
ControlFlow::Continue(())
}
}
}
struct PrivateItemsInPublicInterfacesChecker<'tcx> {
tcx: TyCtxt<'tcx>,
old_error_set_ancestry: LocalDefIdSet,
}
impl<'tcx> PrivateItemsInPublicInterfacesChecker<'tcx> {
fn check(
&self,
def_id: LocalDefId,
required_visibility: ty::Visibility,
) -> SearchInterfaceForPrivateItemsVisitor<'tcx> {
SearchInterfaceForPrivateItemsVisitor {
tcx: self.tcx,
item_def_id: def_id,
required_visibility,
has_old_errors: self.old_error_set_ancestry.contains(&def_id),
in_assoc_ty: false,
}
}
fn check_assoc_item(
&self,
def_id: LocalDefId,
assoc_item_kind: AssocItemKind,
vis: ty::Visibility,
) {
let mut check = self.check(def_id, vis);
let (check_ty, is_assoc_ty) = match assoc_item_kind {
AssocItemKind::Const | AssocItemKind::Fn { .. } => (true, false),
AssocItemKind::Type => (self.tcx.impl_defaultness(def_id).has_value(), true),
};
check.in_assoc_ty = is_assoc_ty;
check.generics().predicates();
if check_ty {
check.ty();
}
}
pub fn check_item(&mut self, id: ItemId) {
let tcx = self.tcx;
let def_id = id.owner_id.def_id;
let item_visibility = tcx.local_visibility(def_id);
let def_kind = tcx.def_kind(def_id);
match def_kind {
DefKind::Const | DefKind::Static(_) | DefKind::Fn | DefKind::TyAlias => {
self.check(def_id, item_visibility).generics().predicates().ty();
}
DefKind::OpaqueTy => {
// `ty()` for opaque types is the underlying type,
// it's not a part of interface, so we skip it.
self.check(def_id, item_visibility).generics().bounds();
}
DefKind::Trait => {
let item = tcx.hir().item(id);
if let hir::ItemKind::Trait(.., trait_item_refs) = item.kind {
self.check(item.owner_id.def_id, item_visibility).generics().predicates();
for trait_item_ref in trait_item_refs {
self.check_assoc_item(
trait_item_ref.id.owner_id.def_id,
trait_item_ref.kind,
item_visibility,
);
if let AssocItemKind::Type = trait_item_ref.kind {
self.check(trait_item_ref.id.owner_id.def_id, item_visibility).bounds();
}
}
}
}
DefKind::TraitAlias => {
self.check(def_id, item_visibility).generics().predicates();
}
DefKind::Enum => {
let item = tcx.hir().item(id);
if let hir::ItemKind::Enum(ref def, _) = item.kind {
self.check(item.owner_id.def_id, item_visibility).generics().predicates();
for variant in def.variants {
for field in variant.data.fields() {
self.check(field.def_id, item_visibility).ty();
}
}
}
}
// Subitems of foreign modules have their own publicity.
DefKind::ForeignMod => {
let item = tcx.hir().item(id);
if let hir::ItemKind::ForeignMod { items, .. } = item.kind {
for foreign_item in items {
let vis = tcx.local_visibility(foreign_item.id.owner_id.def_id);
self.check(foreign_item.id.owner_id.def_id, vis)
.generics()
.predicates()
.ty();
}
}
}
// Subitems of structs and unions have their own publicity.
DefKind::Struct | DefKind::Union => {
let item = tcx.hir().item(id);
if let hir::ItemKind::Struct(ref struct_def, _)
| hir::ItemKind::Union(ref struct_def, _) = item.kind
{
self.check(item.owner_id.def_id, item_visibility).generics().predicates();
for field in struct_def.fields() {
let field_visibility = tcx.local_visibility(field.def_id);
self.check(field.def_id, min(item_visibility, field_visibility, tcx)).ty();
}
}
}
// An inherent impl is public when its type is public
// Subitems of inherent impls have their own publicity.
// A trait impl is public when both its type and its trait are public
// Subitems of trait impls have inherited publicity.
DefKind::Impl => {
let item = tcx.hir().item(id);
if let hir::ItemKind::Impl(ref impl_) = item.kind {
let impl_vis =
ty::Visibility::of_impl(item.owner_id.def_id, tcx, &Default::default());
// check that private components do not appear in the generics or predicates of inherent impls
// this check is intentionally NOT performed for impls of traits, per #90586
if impl_.of_trait.is_none() {
self.check(item.owner_id.def_id, impl_vis).generics().predicates();
}
for impl_item_ref in impl_.items {
let impl_item_vis = if impl_.of_trait.is_none() {
min(
tcx.local_visibility(impl_item_ref.id.owner_id.def_id),
impl_vis,
tcx,
)
} else {
impl_vis
};
self.check_assoc_item(
impl_item_ref.id.owner_id.def_id,
impl_item_ref.kind,
impl_item_vis,
);
}
}
}
_ => {}
}
}
}
pub fn provide(providers: &mut Providers) {
*providers = Providers {
visibility,
effective_visibilities,
check_private_in_public,
check_mod_privacy,
..*providers
};
}
fn visibility(tcx: TyCtxt<'_>, def_id: DefId) -> ty::Visibility {
local_visibility(tcx, def_id.expect_local()).to_def_id()
}
fn local_visibility(tcx: TyCtxt<'_>, def_id: LocalDefId) -> ty::Visibility {
match tcx.resolutions(()).visibilities.get(&def_id) {
Some(vis) => *vis,
None => {
let hir_id = tcx.hir().local_def_id_to_hir_id(def_id);
match tcx.hir().get(hir_id) {
// Unique types created for closures participate in type privacy checking.
// They have visibilities inherited from the module they are defined in.
Node::Expr(hir::Expr { kind: hir::ExprKind::Closure{..}, .. })
// - AST lowering creates dummy `use` items which don't
// get their entries in the resolver's visibility table.
// - AST lowering also creates opaque type items with inherited visibilities.
// Visibility on them should have no effect, but to avoid the visibility
// query failing on some items, we provide it for opaque types as well.
| Node::Item(hir::Item {
kind: hir::ItemKind::Use(_, hir::UseKind::ListStem)
| hir::ItemKind::OpaqueTy(..),
..
}) => ty::Visibility::Restricted(tcx.parent_module(hir_id)),
// Visibilities of trait impl items are inherited from their traits
// and are not filled in resolve.
Node::ImplItem(impl_item) => {
match tcx.hir().get_by_def_id(tcx.hir().get_parent_item(hir_id).def_id) {
Node::Item(hir::Item {
kind: hir::ItemKind::Impl(hir::Impl { of_trait: Some(tr), .. }),
..
}) => tr.path.res.opt_def_id().map_or_else(
|| {
tcx.sess.delay_span_bug(tr.path.span, "trait without a def-id");
ty::Visibility::Public
},
|def_id| tcx.visibility(def_id).expect_local(),
),
_ => span_bug!(impl_item.span, "the parent is not a trait impl"),
}
}
_ => span_bug!(
tcx.def_span(def_id),
"visibility table unexpectedly missing a def-id: {:?}",
def_id,
),
}
}
}
}
fn check_mod_privacy(tcx: TyCtxt<'_>, module_def_id: LocalDefId) {
// Check privacy of names not checked in previous compilation stages.
let mut visitor =
NamePrivacyVisitor { tcx, maybe_typeck_results: None, current_item: module_def_id };
let (module, span, hir_id) = tcx.hir().get_module(module_def_id);
intravisit::walk_mod(&mut visitor, module, hir_id);
// Check privacy of explicitly written types and traits as well as
// inferred types of expressions and patterns.
let mut visitor =
TypePrivacyVisitor { tcx, maybe_typeck_results: None, current_item: module_def_id, span };
intravisit::walk_mod(&mut visitor, module, hir_id);
}
fn effective_visibilities(tcx: TyCtxt<'_>, (): ()) -> &EffectiveVisibilities {
// Build up a set of all exported items in the AST. This is a set of all
// items which are reachable from external crates based on visibility.
let mut visitor = EmbargoVisitor {
tcx,
effective_visibilities: tcx.resolutions(()).effective_visibilities.clone(),
macro_reachable: Default::default(),
prev_level: Some(Level::Direct),
changed: false,
};
visitor.effective_visibilities.check_invariants(tcx, true);
loop {
tcx.hir().walk_toplevel_module(&mut visitor);
if visitor.changed {
visitor.changed = false;
} else {
break;
}
}
visitor.effective_visibilities.check_invariants(tcx, false);
let mut check_visitor =
TestReachabilityVisitor { tcx, effective_visibilities: &visitor.effective_visibilities };
tcx.hir().visit_all_item_likes_in_crate(&mut check_visitor);
tcx.arena.alloc(visitor.effective_visibilities)
}
fn check_private_in_public(tcx: TyCtxt<'_>, (): ()) {
let effective_visibilities = tcx.effective_visibilities(());
let mut visitor = ObsoleteVisiblePrivateTypesVisitor {
tcx,
effective_visibilities,
in_variant: false,
old_error_set: Default::default(),
};
tcx.hir().walk_toplevel_module(&mut visitor);
let mut old_error_set_ancestry = HirIdSet::default();
for mut id in visitor.old_error_set.iter().copied() {
loop {
if !old_error_set_ancestry.insert(id) {
break;
}
let parent = tcx.hir().parent_id(id);
if parent == id {
break;
}
id = parent;
}
}
// Check for private types and traits in public interfaces.
let mut checker = PrivateItemsInPublicInterfacesChecker {
tcx,
// Only definition IDs are ever searched in `old_error_set_ancestry`,
// so we can filter away all non-definition IDs at this point.
old_error_set_ancestry: old_error_set_ancestry
.into_iter()
.filter_map(|hir_id| tcx.hir().opt_local_def_id(hir_id))
.collect(),
};
for id in tcx.hir().items() {
checker.check_item(id);
}
}