use rustc_middle::traits::solve::{Certainty, Goal, QueryResult};
use rustc_middle::ty;
use super::EvalCtxt;
impl<'tcx> EvalCtxt<'_, 'tcx> {
pub(super) fn normalize_inherent_associated_type(
&mut self,
goal: Goal<'tcx, ty::ProjectionPredicate<'tcx>>,
) -> QueryResult<'tcx> {
let tcx = self.tcx();
let inherent = goal.predicate.projection_ty;
let expected = goal.predicate.term.ty().expect("inherent consts are treated separately");
let impl_def_id = tcx.parent(inherent.def_id);
let impl_substs = self.fresh_args_for_item(impl_def_id);
self.eq(
goal.param_env,
inherent.self_ty(),
tcx.type_of(impl_def_id).instantiate(tcx, impl_substs),
)?;
let inherent_substs = inherent.rebase_inherent_args_onto_impl(impl_substs, tcx);
self.eq(
goal.param_env,
expected,
tcx.type_of(inherent.def_id).instantiate(tcx, inherent_substs),
)
.expect("expected goal term to be fully unconstrained");
self.add_goals(
tcx.predicates_of(inherent.def_id)
.instantiate(tcx, inherent_substs)
.into_iter()
.map(|(pred, _)| goal.with(tcx, pred)),
);
self.evaluate_added_goals_and_make_canonical_response(Certainty::Yes)
}
}