From ed7bdbb17b9c03fe3530e5e3f21b7c6c7879dbca Mon Sep 17 00:00:00 2001 From: Michael Goulet Date: Fri, 9 Aug 2024 22:02:20 -0400 Subject: [PATCH 1/2] Store do_not_recommend-ness in impl header --- compiler/rustc_hir_analysis/src/collect.rs | 2 ++ compiler/rustc_middle/src/ty/context.rs | 6 ++++++ compiler/rustc_middle/src/ty/mod.rs | 1 + .../traits/fulfillment_errors.rs | 18 +++--------------- .../rustc_trait_selection/src/solve/fulfill.rs | 6 +----- 5 files changed, 13 insertions(+), 20 deletions(-) diff --git a/compiler/rustc_hir_analysis/src/collect.rs b/compiler/rustc_hir_analysis/src/collect.rs index 47ff748547a90..07bf5d90b55fa 100644 --- a/compiler/rustc_hir_analysis/src/collect.rs +++ b/compiler/rustc_hir_analysis/src/collect.rs @@ -1699,6 +1699,8 @@ fn impl_trait_header(tcx: TyCtxt<'_>, def_id: LocalDefId) -> Option TyCtxt<'tcx> { pub fn impl_polarity(self, def_id: impl IntoQueryParam) -> ty::ImplPolarity { self.impl_trait_header(def_id).map_or(ty::ImplPolarity::Positive, |h| h.polarity) } + + /// Whether this is a trait implementation that has `#[diagnostic::do_not_recommend]` + pub fn do_not_recommend_impl(self, def_id: DefId) -> bool { + matches!(self.def_kind(def_id), DefKind::Impl { of_trait: true }) + && self.impl_trait_header(def_id).is_some_and(|header| header.do_not_recommend) + } } /// Parameter attributes that can only be determined by examining the body of a function instead diff --git a/compiler/rustc_middle/src/ty/mod.rs b/compiler/rustc_middle/src/ty/mod.rs index 9736428e6f7c7..69b194045ad08 100644 --- a/compiler/rustc_middle/src/ty/mod.rs +++ b/compiler/rustc_middle/src/ty/mod.rs @@ -262,6 +262,7 @@ pub struct ImplTraitHeader<'tcx> { pub trait_ref: ty::EarlyBinder<'tcx, ty::TraitRef<'tcx>>, pub polarity: ImplPolarity, pub safety: hir::Safety, + pub do_not_recommend: bool, } #[derive(Copy, Clone, PartialEq, Eq, Debug, TypeFoldable, TypeVisitable)] diff --git a/compiler/rustc_trait_selection/src/error_reporting/traits/fulfillment_errors.rs b/compiler/rustc_trait_selection/src/error_reporting/traits/fulfillment_errors.rs index 1cee82f04ea0e..7f7de4a963b68 100644 --- a/compiler/rustc_trait_selection/src/error_reporting/traits/fulfillment_errors.rs +++ b/compiler/rustc_trait_selection/src/error_reporting/traits/fulfillment_errors.rs @@ -687,10 +687,7 @@ impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> { let mut applied_do_not_recommend = false; loop { if let ObligationCauseCode::ImplDerived(ref c) = base_cause { - if self.tcx.has_attrs_with_path( - c.impl_or_alias_def_id, - &[sym::diagnostic, sym::do_not_recommend], - ) { + if self.tcx.do_not_recommend_impl(c.impl_or_alias_def_id) { let code = (*c.derived.parent_code).clone(); obligation.cause.map_code(|_| code); obligation.predicate = c.derived.parent_trait_pred.upcast(self.tcx); @@ -1630,11 +1627,7 @@ impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> { .tcx .all_impls(def_id) // ignore `do_not_recommend` items - .filter(|def_id| { - !self - .tcx - .has_attrs_with_path(*def_id, &[sym::diagnostic, sym::do_not_recommend]) - }) + .filter(|def_id| !self.tcx.do_not_recommend_impl(*def_id)) // Ignore automatically derived impls and `!Trait` impls. .filter_map(|def_id| self.tcx.impl_trait_header(def_id)) .filter_map(|header| { @@ -1904,12 +1897,7 @@ impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> { let impl_candidates = impl_candidates .into_iter() .cloned() - .filter(|cand| { - !self.tcx.has_attrs_with_path( - cand.impl_def_id, - &[sym::diagnostic, sym::do_not_recommend], - ) - }) + .filter(|cand| !self.tcx.do_not_recommend_impl(cand.impl_def_id)) .collect::>(); let def_id = trait_ref.def_id(); diff --git a/compiler/rustc_trait_selection/src/solve/fulfill.rs b/compiler/rustc_trait_selection/src/solve/fulfill.rs index 49fa775a0a191..de8951ef72046 100644 --- a/compiler/rustc_trait_selection/src/solve/fulfill.rs +++ b/compiler/rustc_trait_selection/src/solve/fulfill.rs @@ -13,7 +13,6 @@ use rustc_middle::bug; use rustc_middle::ty::error::{ExpectedFound, TypeError}; use rustc_middle::ty::{self, TyCtxt}; use rustc_next_trait_solver::solve::{GenerateProofTree, SolverDelegateEvalExt as _}; -use rustc_span::symbol::sym; use super::delegate::SolverDelegate; use super::inspect::{self, ProofTreeInferCtxtExt, ProofTreeVisitor}; @@ -440,10 +439,7 @@ impl<'tcx> ProofTreeVisitor<'tcx> for BestObligation<'tcx> { source: CandidateSource::Impl(impl_def_id), result: _, } = candidate.kind() - && goal - .infcx() - .tcx - .has_attrs_with_path(impl_def_id, &[sym::diagnostic, sym::do_not_recommend]) + && goal.infcx().tcx.do_not_recommend_impl(impl_def_id) { return ControlFlow::Break(self.obligation.clone()); } From 20a16bb3c54ea7523ebd0c933fe5674aea50942e Mon Sep 17 00:00:00 2001 From: Michael Goulet Date: Fri, 9 Aug 2024 21:14:07 -0400 Subject: [PATCH 2/2] Add test Co-authored-by: Georg Semmler --- ...ot_apply_attribute_without_feature_flag.rs | 21 +++++++++++++++++++ ...pply_attribute_without_feature_flag.stderr | 21 +++++++++++++++++++ 2 files changed, 42 insertions(+) create mode 100644 tests/ui/diagnostic_namespace/do_not_recommend/do_not_apply_attribute_without_feature_flag.rs create mode 100644 tests/ui/diagnostic_namespace/do_not_recommend/do_not_apply_attribute_without_feature_flag.stderr diff --git a/tests/ui/diagnostic_namespace/do_not_recommend/do_not_apply_attribute_without_feature_flag.rs b/tests/ui/diagnostic_namespace/do_not_recommend/do_not_apply_attribute_without_feature_flag.rs new file mode 100644 index 0000000000000..5548fa2f52e17 --- /dev/null +++ b/tests/ui/diagnostic_namespace/do_not_recommend/do_not_apply_attribute_without_feature_flag.rs @@ -0,0 +1,21 @@ +#![allow(unknown_or_malformed_diagnostic_attributes)] + +trait Foo {} + +#[diagnostic::do_not_recommend] +impl Foo for (A,) {} + +#[diagnostic::do_not_recommend] +impl Foo for (A, B) {} + +#[diagnostic::do_not_recommend] +impl Foo for (A, B, C) {} + +impl Foo for i32 {} + +fn check(a: impl Foo) {} + +fn main() { + check(()); + //~^ ERROR the trait bound `(): Foo` is not satisfied +} diff --git a/tests/ui/diagnostic_namespace/do_not_recommend/do_not_apply_attribute_without_feature_flag.stderr b/tests/ui/diagnostic_namespace/do_not_recommend/do_not_apply_attribute_without_feature_flag.stderr new file mode 100644 index 0000000000000..e56af28f3fb5d --- /dev/null +++ b/tests/ui/diagnostic_namespace/do_not_recommend/do_not_apply_attribute_without_feature_flag.stderr @@ -0,0 +1,21 @@ +error[E0277]: the trait bound `(): Foo` is not satisfied + --> $DIR/do_not_apply_attribute_without_feature_flag.rs:19:11 + | +LL | check(()); + | ----- ^^ the trait `Foo` is not implemented for `()` + | | + | required by a bound introduced by this call + | + = help: the following other types implement trait `Foo`: + (A, B) + (A, B, C) + (A,) +note: required by a bound in `check` + --> $DIR/do_not_apply_attribute_without_feature_flag.rs:16:18 + | +LL | fn check(a: impl Foo) {} + | ^^^ required by this bound in `check` + +error: aborting due to 1 previous error + +For more information about this error, try `rustc --explain E0277`.