use rustc_hir::def_id::{DefId, LocalDefId};
use rustc_hir::intravisit::{walk_generics, Visitor as _};
use rustc_hir::{GenericArg, GenericArgs, OpaqueTyOrigin};
-use rustc_infer::infer::TyCtxtInferExt;
+use rustc_infer::infer::{InferCtxt, TyCtxtInferExt};
use rustc_middle::middle::stability::AllowUnstable;
use rustc_middle::ty::subst::{self, GenericArgKind, InternalSubsts, SubstsRef};
use rustc_middle::ty::GenericParamDefKind;
use rustc_span::edition::Edition;
use rustc_span::lev_distance::find_best_match_for_name;
use rustc_span::symbol::{kw, Ident, Symbol};
-use rustc_span::{sym, Span};
+use rustc_span::{sym, Span, DUMMY_SP};
use rustc_target::spec::abi;
use rustc_trait_selection::traits;
use rustc_trait_selection::traits::astconv_object_safety_violations;
pub struct PathSeg(pub DefId, pub usize);
pub trait AstConv<'tcx> {
- fn tcx<'a>(&'a self) -> TyCtxt<'tcx>;
+ fn tcx(&self) -> TyCtxt<'tcx>;
fn item_def_id(&self) -> DefId;
{
self
}
+
+ fn infcx(&self) -> Option<&InferCtxt<'tcx>>;
}
#[derive(Debug)]
)
.emit() // Already reported in an earlier stage.
} else {
- // Find all the `impl`s that `qself_ty` has for any trait that has the
- // associated type, so that we suggest the right one.
- let infcx = tcx.infer_ctxt().build();
- // We create a fresh `ty::ParamEnv` instead of the one for `self.item_def_id()`
- // to avoid a cycle error in `src/test/ui/resolve/issue-102946.rs`.
- let param_env = ty::ParamEnv::empty();
- let traits: Vec<_> = self
- .tcx()
- .all_traits()
- .filter(|trait_def_id| {
- // Consider only traits with the associated type
- tcx.associated_items(*trait_def_id)
- .in_definition_order()
- .any(|i| {
- i.kind.namespace() == Namespace::TypeNS
- && i.ident(tcx).normalize_to_macros_2_0() == assoc_ident
- && matches!(i.kind, ty::AssocKind::Type)
- })
- // Consider only accessible traits
- && tcx.visibility(*trait_def_id)
- .is_accessible_from(self.item_def_id(), tcx)
- && tcx.all_impls(*trait_def_id)
- .any(|impl_def_id| {
- let trait_ref = tcx.impl_trait_ref(impl_def_id);
- trait_ref.map_or(false, |trait_ref| {
- let impl_ = trait_ref.subst(
- tcx,
- infcx.fresh_substs_for_item(span, impl_def_id),
- );
- infcx
- .can_eq(
- param_env,
- tcx.erase_regions(impl_.self_ty()),
- tcx.erase_regions(qself_ty),
- )
- .is_ok()
- })
- && tcx.impl_polarity(impl_def_id) != ty::ImplPolarity::Negative
- })
- })
- .map(|trait_def_id| tcx.def_path_str(trait_def_id))
- .collect();
+ let traits: Vec<_> =
+ self.probe_traits_that_match_assoc_ty(qself_ty, assoc_ident);
// Don't print `TyErr` to the user.
self.report_ambiguous_associated_type(
Ok((ty, DefKind::AssocTy, assoc_ty_did))
}
+ fn probe_traits_that_match_assoc_ty(
+ &self,
+ qself_ty: Ty<'tcx>,
+ assoc_ident: Ident,
+ ) -> Vec<String> {
+ let tcx = self.tcx();
+
+ // In contexts that have no inference context, just make a new one.
+ // We do need a local variable to store it, though.
+ let infcx_;
+ let infcx = if let Some(infcx) = self.infcx() {
+ infcx
+ } else {
+ assert!(!qself_ty.needs_infer());
+ infcx_ = tcx.infer_ctxt().build();
+ &infcx_
+ };
+
+ tcx.all_traits()
+ .filter(|trait_def_id| {
+ // Consider only traits with the associated type
+ tcx.associated_items(*trait_def_id)
+ .in_definition_order()
+ .any(|i| {
+ i.kind.namespace() == Namespace::TypeNS
+ && i.ident(tcx).normalize_to_macros_2_0() == assoc_ident
+ && matches!(i.kind, ty::AssocKind::Type)
+ })
+ // Consider only accessible traits
+ && tcx.visibility(*trait_def_id)
+ .is_accessible_from(self.item_def_id(), tcx)
+ && tcx.all_impls(*trait_def_id)
+ .any(|impl_def_id| {
+ let trait_ref = tcx.impl_trait_ref(impl_def_id);
+ trait_ref.map_or(false, |trait_ref| {
+ let impl_ = trait_ref.subst(
+ tcx,
+ infcx.fresh_substs_for_item(DUMMY_SP, impl_def_id),
+ );
+ infcx
+ .can_eq(
+ ty::ParamEnv::empty(),
+ tcx.erase_regions(impl_.self_ty()),
+ tcx.erase_regions(qself_ty),
+ )
+ .is_ok()
+ })
+ && tcx.impl_polarity(impl_def_id) != ty::ImplPolarity::Negative
+ })
+ })
+ .map(|trait_def_id| tcx.def_path_str(trait_def_id))
+ .collect()
+ }
+
fn lookup_assoc_ty(
&self,
ident: Ident,
let hir::Node::ImplItem(hir::ImplItem { kind: hir::ImplItemKind::Fn(..), ident, .. }) =
hir.get(fn_hir_id) else { return None };
- let hir::Node::Item(hir::Item { kind: hir::ItemKind::Impl(i), .. }) =
- hir.get_parent(fn_hir_id) else { bug!("ImplItem should have Impl parent") };
+ let i = hir.get_parent(fn_hir_id).expect_item().expect_impl();
let trait_ref = self.instantiate_mono_trait_ref(
i.of_trait.as_ref()?,
trait_ref.def_id,
)?;
- let fn_sig = tcx.bound_fn_sig(assoc.def_id).subst(
+ let fn_sig = tcx.fn_sig(assoc.def_id).subst(
tcx,
trait_ref.substs.extend_to(tcx, assoc.def_id, |param, _| tcx.mk_param_from_def(param)),
);