Add rustc_deny_explicit_impl

This commit is contained in:
Michael Goulet 2022-11-12 23:37:52 +00:00
parent 742d3f02c2
commit b5b6467810
6 changed files with 28 additions and 50 deletions

View file

@ -5,10 +5,11 @@
// done by the orphan and overlap modules. Then we build up various
// mappings. That mapping code resides here.
use rustc_errors::struct_span_err;
use rustc_errors::{error_code, struct_span_err};
use rustc_hir::def_id::{DefId, LocalDefId};
use rustc_middle::ty::query::Providers;
use rustc_middle::ty::{self, TyCtxt, TypeVisitable};
use rustc_span::sym;
use rustc_trait_selection::traits;
mod builtin;
@ -39,61 +40,26 @@ fn enforce_trait_manually_implementable(
impl_def_id: LocalDefId,
trait_def_id: DefId,
) {
let did = Some(trait_def_id);
let li = tcx.lang_items();
let impl_header_span = tcx.def_span(impl_def_id);
// Disallow *all* explicit impls of `Pointee`, `DiscriminantKind`, `Sized` and `Unsize` for now.
if did == li.pointee_trait() {
struct_span_err!(
// Disallow *all* explicit impls of traits marked `#[rustc_deny_explicit_impl]`
if tcx.has_attr(trait_def_id, sym::rustc_deny_explicit_impl) {
let trait_name = tcx.item_name(trait_def_id);
let mut err = struct_span_err!(
tcx.sess,
impl_header_span,
E0322,
"explicit impls for the `Pointee` trait are not permitted"
)
.span_label(impl_header_span, "impl of `Pointee` not allowed")
.emit();
return;
}
"explicit impls for the `{trait_name}` trait are not permitted"
);
err.span_label(impl_header_span, format!("impl of `{trait_name}` not allowed"));
if did == li.discriminant_kind_trait() {
struct_span_err!(
tcx.sess,
impl_header_span,
E0322,
"explicit impls for the `DiscriminantKind` trait are not permitted"
)
.span_label(impl_header_span, "impl of `DiscriminantKind` not allowed")
.emit();
return;
}
// Maintain explicit error code for `Unsize`, since it has a useful
// explanation about using `CoerceUnsized` instead.
if Some(trait_def_id) == tcx.lang_items().unsize_trait() {
err.code(error_code!(E0328));
}
if did == li.sized_trait() {
struct_span_err!(
tcx.sess,
impl_header_span,
E0322,
"explicit impls for the `Sized` trait are not permitted"
)
.span_label(impl_header_span, "impl of `Sized` not allowed")
.emit();
return;
}
if did == li.unsize_trait() {
struct_span_err!(
tcx.sess,
impl_header_span,
E0328,
"explicit impls for the `Unsize` trait are not permitted"
)
.span_label(impl_header_span, "impl of `Unsize` not allowed")
.emit();
return;
}
if tcx.features().unboxed_closures {
// the feature gate allows all Fn traits
err.emit();
return;
}