diff options
Diffstat (limited to 'src/librustdoc/clean/blanket_impl.rs')
| -rw-r--r-- | src/librustdoc/clean/blanket_impl.rs | 209 |
1 files changed, 105 insertions, 104 deletions
diff --git a/src/librustdoc/clean/blanket_impl.rs b/src/librustdoc/clean/blanket_impl.rs index cc734389e..8b63c3db3 100644 --- a/src/librustdoc/clean/blanket_impl.rs +++ b/src/librustdoc/clean/blanket_impl.rs @@ -2,7 +2,6 @@ use crate::rustc_trait_selection::traits::query::evaluate_obligation::InferCtxtE use rustc_hir as hir; use rustc_infer::infer::{InferOk, TyCtxtInferExt}; use rustc_infer::traits; -use rustc_middle::ty::subst::Subst; use rustc_middle::ty::ToPredicate; use rustc_span::DUMMY_SP; @@ -14,122 +13,124 @@ pub(crate) struct BlanketImplFinder<'a, 'tcx> { impl<'a, 'tcx> BlanketImplFinder<'a, 'tcx> { pub(crate) fn get_blanket_impls(&mut self, item_def_id: DefId) -> Vec<Item> { - let param_env = self.cx.tcx.param_env(item_def_id); - let ty = self.cx.tcx.bound_type_of(item_def_id); + let cx = &mut self.cx; + let param_env = cx.tcx.param_env(item_def_id); + let ty = cx.tcx.bound_type_of(item_def_id); trace!("get_blanket_impls({:?})", ty); let mut impls = Vec::new(); - self.cx.with_all_traits(|cx, all_traits| { - for &trait_def_id in all_traits { - if !cx.cache.access_levels.is_public(trait_def_id) - || cx.generated_synthetics.get(&(ty.0, trait_def_id)).is_some() - { + for trait_def_id in cx.tcx.all_traits() { + if !cx.cache.effective_visibilities.is_directly_public(trait_def_id) + || cx.generated_synthetics.get(&(ty.0, trait_def_id)).is_some() + { + continue; + } + // NOTE: doesn't use `for_each_relevant_impl` to avoid looking at anything besides blanket impls + let trait_impls = cx.tcx.trait_impls_of(trait_def_id); + 'blanket_impls: for &impl_def_id in trait_impls.blanket_impls() { + trace!( + "get_blanket_impls: Considering impl for trait '{:?}' {:?}", + trait_def_id, + impl_def_id + ); + let trait_ref = cx.tcx.bound_impl_trait_ref(impl_def_id).unwrap(); + if !matches!(trait_ref.0.self_ty().kind(), ty::Param(_)) { continue; } - // NOTE: doesn't use `for_each_relevant_impl` to avoid looking at anything besides blanket impls - let trait_impls = cx.tcx.trait_impls_of(trait_def_id); - for &impl_def_id in trait_impls.blanket_impls() { - trace!( - "get_blanket_impls: Considering impl for trait '{:?}' {:?}", - trait_def_id, - impl_def_id - ); - let trait_ref = cx.tcx.bound_impl_trait_ref(impl_def_id).unwrap(); - let is_param = matches!(trait_ref.0.self_ty().kind(), ty::Param(_)); - let may_apply = is_param && cx.tcx.infer_ctxt().enter(|infcx| { - let substs = infcx.fresh_substs_for_item(DUMMY_SP, item_def_id); - let ty = ty.subst(infcx.tcx, substs); - let param_env = EarlyBinder(param_env).subst(infcx.tcx, substs); + let infcx = cx.tcx.infer_ctxt().build(); + let substs = infcx.fresh_substs_for_item(DUMMY_SP, item_def_id); + let impl_ty = ty.subst(infcx.tcx, substs); + let param_env = EarlyBinder(param_env).subst(infcx.tcx, substs); - let impl_substs = infcx.fresh_substs_for_item(DUMMY_SP, impl_def_id); - let trait_ref = trait_ref.subst(infcx.tcx, impl_substs); + let impl_substs = infcx.fresh_substs_for_item(DUMMY_SP, impl_def_id); + let impl_trait_ref = trait_ref.subst(infcx.tcx, impl_substs); - // Require the type the impl is implemented on to match - // our type, and ignore the impl if there was a mismatch. - let cause = traits::ObligationCause::dummy(); - let eq_result = infcx.at(&cause, param_env).eq(trait_ref.self_ty(), ty); - if let Ok(InferOk { value: (), obligations }) = eq_result { - // FIXME(eddyb) ignoring `obligations` might cause false positives. - drop(obligations); + // Require the type the impl is implemented on to match + // our type, and ignore the impl if there was a mismatch. + let cause = traits::ObligationCause::dummy(); + let Ok(eq_result) = infcx.at(&cause, param_env).eq(impl_trait_ref.self_ty(), impl_ty) else { + continue + }; + let InferOk { value: (), obligations } = eq_result; + // FIXME(eddyb) ignoring `obligations` might cause false positives. + drop(obligations); - trace!( - "invoking predicate_may_hold: param_env={:?}, trait_ref={:?}, ty={:?}", - param_env, - trait_ref, - ty - ); - let predicates = cx - .tcx - .predicates_of(impl_def_id) - .instantiate(cx.tcx, impl_substs) - .predicates - .into_iter() - .chain(Some( - ty::Binder::dummy(trait_ref) - .to_poly_trait_predicate() - .map_bound(ty::PredicateKind::Trait) - .to_predicate(infcx.tcx), - )); - for predicate in predicates { - debug!("testing predicate {:?}", predicate); - let obligation = traits::Obligation::new( - traits::ObligationCause::dummy(), - param_env, - predicate, - ); - match infcx.evaluate_obligation(&obligation) { - Ok(eval_result) if eval_result.may_apply() => {} - Err(traits::OverflowError::Canonical) => {} - Err(traits::OverflowError::ErrorReporting) => {} - _ => { - return false; - } - } - } - true - } else { - false - } - }); - debug!( - "get_blanket_impls: found applicable impl: {} for trait_ref={:?}, ty={:?}", - may_apply, trait_ref, ty + trace!( + "invoking predicate_may_hold: param_env={:?}, impl_trait_ref={:?}, impl_ty={:?}", + param_env, + impl_trait_ref, + impl_ty + ); + let predicates = cx + .tcx + .predicates_of(impl_def_id) + .instantiate(cx.tcx, impl_substs) + .predicates + .into_iter() + .chain(Some( + ty::Binder::dummy(impl_trait_ref) + .to_poly_trait_predicate() + .map_bound(ty::PredicateKind::Trait) + .to_predicate(infcx.tcx), + )); + for predicate in predicates { + debug!("testing predicate {:?}", predicate); + let obligation = traits::Obligation::new( + traits::ObligationCause::dummy(), + param_env, + predicate, ); - if !may_apply { - continue; + match infcx.evaluate_obligation(&obligation) { + Ok(eval_result) if eval_result.may_apply() => {} + Err(traits::OverflowError::Canonical) => {} + Err(traits::OverflowError::ErrorReporting) => {} + _ => continue 'blanket_impls, } + } + debug!( + "get_blanket_impls: found applicable impl for trait_ref={:?}, ty={:?}", + trait_ref, ty + ); - cx.generated_synthetics.insert((ty.0, trait_def_id)); + cx.generated_synthetics.insert((ty.0, trait_def_id)); - impls.push(Item { - name: None, - attrs: Default::default(), - visibility: Inherited, - item_id: ItemId::Blanket { impl_id: impl_def_id, for_: item_def_id }, - kind: Box::new(ImplItem(Box::new(Impl { - unsafety: hir::Unsafety::Normal, - generics: clean_ty_generics( - cx, - cx.tcx.generics_of(impl_def_id), - cx.tcx.explicit_predicates_of(impl_def_id), - ), - // FIXME(eddyb) compute both `trait_` and `for_` from - // the post-inference `trait_ref`, as it's more accurate. - trait_: Some(clean_trait_ref_with_bindings(cx, trait_ref.0, ThinVec::new())), - for_: clean_middle_ty(ty.0, cx, None), - items: cx.tcx - .associated_items(impl_def_id) - .in_definition_order() - .map(|x| clean_middle_assoc_item(x, cx)) - .collect::<Vec<_>>(), - polarity: ty::ImplPolarity::Positive, - kind: ImplKind::Blanket(Box::new(clean_middle_ty(trait_ref.0.self_ty(), cx, None))), - }))), - cfg: None, - }); - } + impls.push(Item { + name: None, + attrs: Default::default(), + visibility: Inherited, + item_id: ItemId::Blanket { impl_id: impl_def_id, for_: item_def_id }, + kind: Box::new(ImplItem(Box::new(Impl { + unsafety: hir::Unsafety::Normal, + generics: clean_ty_generics( + cx, + cx.tcx.generics_of(impl_def_id), + cx.tcx.explicit_predicates_of(impl_def_id), + ), + // FIXME(eddyb) compute both `trait_` and `for_` from + // the post-inference `trait_ref`, as it's more accurate. + trait_: Some(clean_trait_ref_with_bindings( + cx, + trait_ref.0, + ThinVec::new(), + )), + for_: clean_middle_ty(ty.0, cx, None), + items: cx + .tcx + .associated_items(impl_def_id) + .in_definition_order() + .map(|x| clean_middle_assoc_item(x, cx)) + .collect::<Vec<_>>(), + polarity: ty::ImplPolarity::Positive, + kind: ImplKind::Blanket(Box::new(clean_middle_ty( + trait_ref.0.self_ty(), + cx, + None, + ))), + }))), + cfg: None, + }); } - }); + } impls } |