diff options
Diffstat (limited to 'compiler/rustc_lint/src/opaque_hidden_inferred_bound.rs')
| -rw-r--r-- | compiler/rustc_lint/src/opaque_hidden_inferred_bound.rs | 21 |
1 files changed, 18 insertions, 3 deletions
diff --git a/compiler/rustc_lint/src/opaque_hidden_inferred_bound.rs b/compiler/rustc_lint/src/opaque_hidden_inferred_bound.rs index 883a56cb3..f9d43fe22 100644 --- a/compiler/rustc_lint/src/opaque_hidden_inferred_bound.rs +++ b/compiler/rustc_lint/src/opaque_hidden_inferred_bound.rs @@ -27,6 +27,8 @@ declare_lint! { /// ### Example /// /// ```rust + /// #![feature(type_alias_impl_trait)] + /// /// trait Duh {} /// /// impl Duh for i32 {} @@ -41,7 +43,9 @@ declare_lint! { /// type Assoc = F; /// } /// - /// fn test() -> impl Trait<Assoc = impl Sized> { + /// type Tait = impl Sized; + /// + /// fn test() -> impl Trait<Assoc = Tait> { /// 42 /// } /// ``` @@ -54,7 +58,7 @@ declare_lint! { /// /// Although the hidden type, `i32` does satisfy this bound, we do not /// consider the return type to be well-formed with this lint. It can be - /// fixed by changing `impl Sized` into `impl Sized + Send`. + /// fixed by changing `Tait = impl Sized` into `Tait = impl Sized + Send`. pub OPAQUE_HIDDEN_INFERRED_BOUND, Warn, "detects the use of nested `impl Trait` types in associated type bounds that are not general enough" @@ -64,7 +68,7 @@ declare_lint_pass!(OpaqueHiddenInferredBound => [OPAQUE_HIDDEN_INFERRED_BOUND]); impl<'tcx> LateLintPass<'tcx> for OpaqueHiddenInferredBound { fn check_item(&mut self, cx: &LateContext<'tcx>, item: &'tcx hir::Item<'tcx>) { - let hir::ItemKind::OpaqueTy(_) = &item.kind else { return; }; + let hir::ItemKind::OpaqueTy(opaque) = &item.kind else { return; }; let def_id = item.owner_id.def_id.to_def_id(); let infcx = &cx.tcx.infer_ctxt().build(); // For every projection predicate in the opaque type's explicit bounds, @@ -81,6 +85,17 @@ impl<'tcx> LateLintPass<'tcx> for OpaqueHiddenInferredBound { // have opaques in them anyways. let Some(proj_term) = proj.term.ty() else { continue }; + // HACK: `impl Trait<Assoc = impl Trait2>` from an RPIT is "ok"... + if let ty::Alias(ty::Opaque, opaque_ty) = *proj_term.kind() + && cx.tcx.parent(opaque_ty.def_id) == def_id + && matches!( + opaque.origin, + hir::OpaqueTyOrigin::FnReturn(_) | hir::OpaqueTyOrigin::AsyncFn(_) + ) + { + continue; + } + let proj_ty = cx.tcx.mk_projection(proj.projection_ty.def_id, proj.projection_ty.substs); // For every instance of the projection type in the bounds, |