add subst_identity_iter and subst_identity_iter_copied methods on EarlyBinder; use this to simplify some EarlyBinder noise around explicit_item_bounds calls

This commit is contained in:
Kyle Matsuda
2023-04-17 17:19:08 -06:00
parent f3b279fcc5
commit e54854f6a9
12 changed files with 43 additions and 50 deletions

View File

@@ -254,29 +254,23 @@ impl<'tcx> LateLintPass<'tcx> for UnusedResults {
}
ty::Adt(def, _) => is_def_must_use(cx, def.did(), span),
ty::Alias(ty::Opaque, ty::AliasTy { def_id: def, .. }) => {
elaborate(
cx.tcx,
cx.tcx
.explicit_item_bounds(def)
.transpose_iter()
.map(|bound| bound.map_bound(|b| *b).subst_identity()),
)
// We only care about self bounds for the impl-trait
.filter_only_self()
.find_map(|(pred, _span)| {
// We only look at the `DefId`, so it is safe to skip the binder here.
if let ty::PredicateKind::Clause(ty::Clause::Trait(
ref poly_trait_predicate,
)) = pred.kind().skip_binder()
{
let def_id = poly_trait_predicate.trait_ref.def_id;
elaborate(cx.tcx, cx.tcx.explicit_item_bounds(def).subst_identity_iter_copied())
// We only care about self bounds for the impl-trait
.filter_only_self()
.find_map(|(pred, _span)| {
// We only look at the `DefId`, so it is safe to skip the binder here.
if let ty::PredicateKind::Clause(ty::Clause::Trait(
ref poly_trait_predicate,
)) = pred.kind().skip_binder()
{
let def_id = poly_trait_predicate.trait_ref.def_id;
is_def_must_use(cx, def_id, span)
} else {
None
}
})
.map(|inner| MustUsePath::Opaque(Box::new(inner)))
is_def_must_use(cx, def_id, span)
} else {
None
}
})
.map(|inner| MustUsePath::Opaque(Box::new(inner)))
}
ty::Dynamic(binders, _, _) => binders.iter().find_map(|predicate| {
if let ty::ExistentialPredicate::Trait(ref trait_ref) = predicate.skip_binder()