use rustc_hir::LangItem;
use rustc_infer::traits::Obligation;
pub use rustc_middle::traits::query::type_op::ProvePredicate;
use rustc_middle::traits::query::NoSolution;
use rustc_middle::traits::ObligationCause;
use rustc_middle::ty::{self, ParamEnvAnd, TyCtxt};
use crate::infer::canonical::{Canonical, CanonicalQueryResponse};
use crate::traits::ObligationCtxt;
impl<'tcx> super::QueryTypeOp<'tcx> for ProvePredicate<'tcx> {
type QueryResponse = ();
fn try_fast_path(
tcx: TyCtxt<'tcx>,
key: &ParamEnvAnd<'tcx, Self>,
) -> Option<Self::QueryResponse> {
if let ty::PredicateKind::Clause(ty::ClauseKind::Trait(trait_ref)) =
key.value.predicate.kind().skip_binder()
&& tcx.is_lang_item(trait_ref.def_id(), LangItem::Sized)
&& trait_ref.self_ty().is_trivially_sized(tcx)
{
return Some(());
}
if let ty::PredicateKind::Clause(ty::ClauseKind::WellFormed(arg)) =
key.value.predicate.kind().skip_binder()
{
match arg.as_type()?.kind() {
ty::Param(_)
| ty::Bool
| ty::Char
| ty::Int(_)
| ty::Float(_)
| ty::Str
| ty::Uint(_) => {
return Some(());
}
_ => {}
}
}
None
}
fn perform_query(
tcx: TyCtxt<'tcx>,
canonicalized: Canonical<'tcx, ParamEnvAnd<'tcx, Self>>,
) -> Result<CanonicalQueryResponse<'tcx, ()>, NoSolution> {
tcx.type_op_prove_predicate(canonicalized)
}
fn perform_locally_with_next_solver(
ocx: &ObligationCtxt<'_, 'tcx>,
key: ParamEnvAnd<'tcx, Self>,
) -> Result<Self::QueryResponse, NoSolution> {
ocx.register_obligation(Obligation::new(
ocx.infcx.tcx,
ObligationCause::dummy(),
key.param_env,
key.value.predicate,
));
Ok(())
}
}