1
Fork 0

Rollup merge of #107880 - jieyouxu:issue-107563, r=petrochenkov

Lint ambiguous glob re-exports

Attempts to fix #107563.

We currently already emit errors for ambiguous re-exports when two names are re-exported *specifically*, i.e. not from glob exports. This PR attempts to emit deny-by-default lints for ambiguous glob re-exports.
This commit is contained in:
Matthias Krüger 2023-03-23 19:55:43 +01:00 committed by GitHub
commit bacf059f57
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
11 changed files with 228 additions and 26 deletions

View file

@ -4,6 +4,7 @@ use rustc_ast::visit;
use rustc_ast::visit::Visitor;
use rustc_ast::Crate;
use rustc_ast::EnumDef;
use rustc_data_structures::fx::FxHashSet;
use rustc_data_structures::intern::Interned;
use rustc_hir::def_id::LocalDefId;
use rustc_hir::def_id::CRATE_DEF_ID;
@ -70,11 +71,11 @@ impl Resolver<'_, '_> {
impl<'r, 'a, 'tcx> EffectiveVisibilitiesVisitor<'r, 'a, 'tcx> {
/// Fills the `Resolver::effective_visibilities` table with public & exported items
/// For now, this doesn't resolve macros (FIXME) and cannot resolve Impl, as we
/// need access to a TyCtxt for that.
/// need access to a TyCtxt for that. Returns the set of ambiguous re-exports.
pub(crate) fn compute_effective_visibilities<'c>(
r: &'r mut Resolver<'a, 'tcx>,
krate: &'c Crate,
) {
) -> FxHashSet<Interned<'a, NameBinding<'a>>> {
let mut visitor = EffectiveVisibilitiesVisitor {
r,
def_effective_visibilities: Default::default(),
@ -93,18 +94,26 @@ impl<'r, 'a, 'tcx> EffectiveVisibilitiesVisitor<'r, 'a, 'tcx> {
}
visitor.r.effective_visibilities = visitor.def_effective_visibilities;
let mut exported_ambiguities = FxHashSet::default();
// Update visibilities for import def ids. These are not used during the
// `EffectiveVisibilitiesVisitor` pass, because we have more detailed binding-based
// information, but are used by later passes. Effective visibility of an import def id
// is the maximum value among visibilities of bindings corresponding to that def id.
for (binding, eff_vis) in visitor.import_effective_visibilities.iter() {
let NameBindingKind::Import { import, .. } = binding.kind else { unreachable!() };
if let Some(node_id) = import.id() {
r.effective_visibilities.update_eff_vis(r.local_def_id(node_id), eff_vis, r.tcx)
if !binding.is_ambiguity() {
if let Some(node_id) = import.id() {
r.effective_visibilities.update_eff_vis(r.local_def_id(node_id), eff_vis, r.tcx)
}
} else if binding.ambiguity.is_some() && eff_vis.is_public_at_level(Level::Reexported) {
exported_ambiguities.insert(*binding);
}
}
info!("resolve::effective_visibilities: {:#?}", r.effective_visibilities);
exported_ambiguities
}
/// Update effective visibilities of bindings in the given module,
@ -115,21 +124,44 @@ impl<'r, 'a, 'tcx> EffectiveVisibilitiesVisitor<'r, 'a, 'tcx> {
let resolutions = self.r.resolutions(module);
for (_, name_resolution) in resolutions.borrow().iter() {
if let Some(mut binding) = name_resolution.borrow().binding() && !binding.is_ambiguity() {
// Set the given effective visibility level to `Level::Direct` and
// sets the rest of the `use` chain to `Level::Reexported` until
// we hit the actual exported item.
let mut parent_id = ParentId::Def(module_id);
while let NameBindingKind::Import { binding: nested_binding, .. } = binding.kind {
let binding_id = ImportId::new_unchecked(binding);
self.update_import(binding_id, parent_id);
if let Some(mut binding) = name_resolution.borrow().binding() {
if !binding.is_ambiguity() {
// Set the given effective visibility level to `Level::Direct` and
// sets the rest of the `use` chain to `Level::Reexported` until
// we hit the actual exported item.
let mut parent_id = ParentId::Def(module_id);
while let NameBindingKind::Import { binding: nested_binding, .. } = binding.kind
{
let binding_id = ImportId::new_unchecked(binding);
self.update_import(binding_id, parent_id);
parent_id = ParentId::Import(binding_id);
binding = nested_binding;
}
parent_id = ParentId::Import(binding_id);
binding = nested_binding;
}
if let Some(def_id) = binding.res().opt_def_id().and_then(|id| id.as_local()) {
self.update_def(def_id, binding.vis.expect_local(), parent_id);
if let Some(def_id) = binding.res().opt_def_id().and_then(|id| id.as_local()) {
self.update_def(def_id, binding.vis.expect_local(), parent_id);
}
} else {
// Put the root ambiguity binding and all reexports leading to it into the
// table. They are used by the `ambiguous_glob_reexports` lint. For all
// bindings added to the table here `is_ambiguity` returns true.
let mut parent_id = ParentId::Def(module_id);
while let NameBindingKind::Import { binding: nested_binding, .. } = binding.kind
{
let binding_id = ImportId::new_unchecked(binding);
self.update_import(binding_id, parent_id);
if binding.ambiguity.is_some() {
// Stop at the root ambiguity, further bindings in the chain should not
// be reexported because the root ambiguity blocks any access to them.
// (Those further bindings are most likely not ambiguities themselves.)
break;
}
parent_id = ParentId::Import(binding_id);
binding = nested_binding;
}
}
}
}

View file

@ -19,7 +19,9 @@ use rustc_hir::def::{self, DefKind, PartialRes};
use rustc_middle::metadata::ModChild;
use rustc_middle::span_bug;
use rustc_middle::ty;
use rustc_session::lint::builtin::{PUB_USE_OF_PRIVATE_EXTERN_CRATE, UNUSED_IMPORTS};
use rustc_session::lint::builtin::{
AMBIGUOUS_GLOB_REEXPORTS, PUB_USE_OF_PRIVATE_EXTERN_CRATE, UNUSED_IMPORTS,
};
use rustc_session::lint::BuiltinLintDiagnostics;
use rustc_span::edit_distance::find_best_match_for_name;
use rustc_span::hygiene::LocalExpnId;
@ -510,6 +512,34 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
}
}
pub(crate) fn check_reexport_ambiguities(
&mut self,
exported_ambiguities: FxHashSet<Interned<'a, NameBinding<'a>>>,
) {
for module in self.arenas.local_modules().iter() {
module.for_each_child(self, |this, ident, ns, binding| {
if let NameBindingKind::Import { import, .. } = binding.kind
&& let Some((amb_binding, _)) = binding.ambiguity
&& binding.res() != Res::Err
&& exported_ambiguities.contains(&Interned::new_unchecked(binding))
{
this.lint_buffer.buffer_lint_with_diagnostic(
AMBIGUOUS_GLOB_REEXPORTS,
import.root_id,
import.root_span,
"ambiguous glob re-exports",
BuiltinLintDiagnostics::AmbiguousGlobReexports {
name: ident.to_string(),
namespace: ns.descr().to_string(),
first_reexport_span: import.root_span,
duplicate_reexport_span: amb_binding.span,
},
);
}
});
}
}
fn throw_unresolved_import_error(&self, errors: Vec<(&Import<'_>, UnresolvedImportError)>) {
if errors.is_empty() {
return;

View file

@ -1475,9 +1475,12 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
pub fn resolve_crate(&mut self, krate: &Crate) {
self.tcx.sess.time("resolve_crate", || {
self.tcx.sess.time("finalize_imports", || self.finalize_imports());
self.tcx.sess.time("compute_effective_visibilities", || {
let exported_ambiguities = self.tcx.sess.time("compute_effective_visibilities", || {
EffectiveVisibilitiesVisitor::compute_effective_visibilities(self, krate)
});
self.tcx.sess.time("check_reexport_ambiguities", || {
self.check_reexport_ambiguities(exported_ambiguities)
});
self.tcx.sess.time("finalize_macro_resolutions", || self.finalize_macro_resolutions());
self.tcx.sess.time("late_resolve_crate", || self.late_resolve_crate(krate));
self.tcx.sess.time("resolve_main", || self.resolve_main());