-use rustc_hir as hir;
use rustc_infer::infer::canonical::{Canonical, QueryResponse};
-use rustc_infer::infer::{DefiningAnchor, TyCtxtInferExt};
-use rustc_infer::traits::ObligationCauseCode;
-use rustc_middle::ty::query::Providers;
-use rustc_middle::ty::{self, FnSig, Lift, PolyFnSig, Ty, TyCtxt, TypeFoldable};
+use rustc_infer::infer::TyCtxtInferExt;
+use rustc_middle::query::Providers;
+use rustc_middle::traits::query::NoSolution;
+use rustc_middle::traits::DefiningAnchor;
+use rustc_middle::ty::{FnSig, Lift, PolyFnSig, Ty, TyCtxt, TypeFoldable};
use rustc_middle::ty::{ParamEnvAnd, Predicate};
-use rustc_middle::ty::{UserSelfTy, UserSubsts, UserType};
-use rustc_span::def_id::CRATE_DEF_ID;
-use rustc_span::{Span, DUMMY_SP};
use rustc_trait_selection::infer::InferCtxtBuilderExt;
use rustc_trait_selection::traits::query::normalize::QueryNormalizeExt;
-use rustc_trait_selection::traits::query::type_op::ascribe_user_type::AscribeUserType;
+use rustc_trait_selection::traits::query::type_op::ascribe_user_type::{
+ type_op_ascribe_user_type_with_span, AscribeUserType,
+};
use rustc_trait_selection::traits::query::type_op::eq::Eq;
use rustc_trait_selection::traits::query::type_op::normalize::Normalize;
use rustc_trait_selection::traits::query::type_op::prove_predicate::ProvePredicate;
use rustc_trait_selection::traits::query::type_op::subtype::Subtype;
-use rustc_trait_selection::traits::query::{Fallible, NoSolution};
use rustc_trait_selection::traits::{Normalized, Obligation, ObligationCause, ObligationCtxt};
use std::fmt;
})
}
-/// The core of the `type_op_ascribe_user_type` query: for diagnostics purposes in NLL HRTB errors,
-/// this query can be re-run to better track the span of the obligation cause, and improve the error
-/// message. Do not call directly unless you're in that very specific context.
-pub fn type_op_ascribe_user_type_with_span<'tcx>(
- ocx: &ObligationCtxt<'_, 'tcx>,
- key: ParamEnvAnd<'tcx, AscribeUserType<'tcx>>,
- span: Option<Span>,
-) -> Result<(), NoSolution> {
- let (param_env, AscribeUserType { mir_ty, user_ty }) = key.into_parts();
- debug!("type_op_ascribe_user_type: mir_ty={:?} user_ty={:?}", mir_ty, user_ty);
- let span = span.unwrap_or(DUMMY_SP);
- match user_ty {
- UserType::Ty(user_ty) => relate_mir_and_user_ty(ocx, param_env, span, mir_ty, user_ty)?,
- UserType::TypeOf(def_id, user_substs) => {
- relate_mir_and_user_substs(ocx, param_env, span, mir_ty, def_id, user_substs)?
- }
- };
- Ok(())
-}
-
-#[instrument(level = "debug", skip(ocx, param_env, span))]
-fn relate_mir_and_user_ty<'tcx>(
- ocx: &ObligationCtxt<'_, 'tcx>,
- param_env: ty::ParamEnv<'tcx>,
- span: Span,
- mir_ty: Ty<'tcx>,
- user_ty: Ty<'tcx>,
-) -> Result<(), NoSolution> {
- let cause = ObligationCause::dummy_with_span(span);
- let user_ty = ocx.normalize(&cause, param_env, user_ty);
- ocx.eq(&cause, param_env, mir_ty, user_ty)?;
-
- // FIXME(#104764): We should check well-formedness before normalization.
- let predicate = ty::Binder::dummy(ty::PredicateKind::WellFormed(user_ty.into()));
- ocx.register_obligation(Obligation::new(ocx.infcx.tcx, cause, param_env, predicate));
- Ok(())
-}
-
-#[instrument(level = "debug", skip(ocx, param_env, span))]
-fn relate_mir_and_user_substs<'tcx>(
- ocx: &ObligationCtxt<'_, 'tcx>,
- param_env: ty::ParamEnv<'tcx>,
- span: Span,
- mir_ty: Ty<'tcx>,
- def_id: hir::def_id::DefId,
- user_substs: UserSubsts<'tcx>,
-) -> Result<(), NoSolution> {
- let UserSubsts { user_self_ty, substs } = user_substs;
- let tcx = ocx.infcx.tcx;
- let cause = ObligationCause::dummy_with_span(span);
-
- let ty = tcx.type_of(def_id).subst(tcx, substs);
- let ty = ocx.normalize(&cause, param_env, ty);
- debug!("relate_type_and_user_type: ty of def-id is {:?}", ty);
-
- ocx.eq(&cause, param_env, mir_ty, ty)?;
-
- // Prove the predicates coming along with `def_id`.
- //
- // Also, normalize the `instantiated_predicates`
- // because otherwise we wind up with duplicate "type
- // outlives" error messages.
- let instantiated_predicates = tcx.predicates_of(def_id).instantiate(tcx, substs);
-
- debug!(?instantiated_predicates);
- for (instantiated_predicate, predicate_span) in instantiated_predicates {
- let span = if span == DUMMY_SP { predicate_span } else { span };
- let cause = ObligationCause::new(
- span,
- CRATE_DEF_ID,
- ObligationCauseCode::AscribeUserTypeProvePredicate(predicate_span),
- );
- let instantiated_predicate =
- ocx.normalize(&cause.clone(), param_env, instantiated_predicate);
-
- ocx.register_obligation(Obligation::new(tcx, cause, param_env, instantiated_predicate));
- }
-
- if let Some(UserSelfTy { impl_def_id, self_ty }) = user_self_ty {
- let self_ty = ocx.normalize(&cause, param_env, self_ty);
- let impl_self_ty = tcx.type_of(impl_def_id).subst(tcx, substs);
- let impl_self_ty = ocx.normalize(&cause, param_env, impl_self_ty);
-
- ocx.eq(&cause, param_env, self_ty, impl_self_ty)?;
- let predicate = ty::Binder::dummy(ty::PredicateKind::WellFormed(impl_self_ty.into()));
- ocx.register_obligation(Obligation::new(tcx, cause.clone(), param_env, predicate));
- }
-
- // In addition to proving the predicates, we have to
- // prove that `ty` is well-formed -- this is because
- // the WF of `ty` is predicated on the substs being
- // well-formed, and we haven't proven *that*. We don't
- // want to prove the WF of types from `substs` directly because they
- // haven't been normalized.
- //
- // FIXME(nmatsakis): Well, perhaps we should normalize
- // them? This would only be relevant if some input
- // type were ill-formed but did not appear in `ty`,
- // which...could happen with normalization...
- let predicate = ty::Binder::dummy(ty::PredicateKind::WellFormed(ty.into()));
- ocx.register_obligation(Obligation::new(tcx, cause, param_env, predicate));
- Ok(())
-}
-
fn type_op_eq<'tcx>(
tcx: TyCtxt<'tcx>,
canonicalized: Canonical<'tcx, ParamEnvAnd<'tcx, Eq<'tcx>>>,
fn type_op_normalize<'tcx, T>(
ocx: &ObligationCtxt<'_, 'tcx>,
key: ParamEnvAnd<'tcx, Normalize<T>>,
-) -> Fallible<T>
+) -> Result<T, NoSolution>
where
T: fmt::Debug + TypeFoldable<TyCtxt<'tcx>> + Lift<'tcx>,
{
projects / rustc.git / blobdiff