use rustc_hir::LangItem;
use rustc_middle::ty::{self, ToPredicate, Ty, TyCtxt};
use rustc_span::Span;
#[derive(Default, PartialEq, Eq, Clone, Debug)]
pub struct Bounds<'tcx> {
pub clauses: Vec<(ty::Clause<'tcx>, Span)>,
}
impl<'tcx> Bounds<'tcx> {
pub fn push_region_bound(
&mut self,
tcx: TyCtxt<'tcx>,
region: ty::PolyTypeOutlivesPredicate<'tcx>,
span: Span,
) {
self.clauses
.push((region.map_bound(|p| ty::ClauseKind::TypeOutlives(p)).to_predicate(tcx), span));
}
pub fn push_trait_bound(
&mut self,
tcx: TyCtxt<'tcx>,
trait_ref: ty::PolyTraitRef<'tcx>,
span: Span,
polarity: ty::ImplPolarity,
) {
self.clauses.push((
trait_ref
.map_bound(|trait_ref| {
ty::ClauseKind::Trait(ty::TraitPredicate { trait_ref, polarity })
})
.to_predicate(tcx),
span,
));
}
pub fn push_projection_bound(
&mut self,
tcx: TyCtxt<'tcx>,
projection: ty::PolyProjectionPredicate<'tcx>,
span: Span,
) {
self.clauses.push((
projection.map_bound(|proj| ty::ClauseKind::Projection(proj)).to_predicate(tcx),
span,
));
}
pub fn push_sized(&mut self, tcx: TyCtxt<'tcx>, ty: Ty<'tcx>, span: Span) {
let sized_def_id = tcx.require_lang_item(LangItem::Sized, Some(span));
let trait_ref = ty::TraitRef::new(tcx, sized_def_id, [ty]);
self.clauses.insert(0, (trait_ref.to_predicate(tcx), span));
}
pub fn clauses(&self) -> impl Iterator<Item = (ty::Clause<'tcx>, Span)> + '_ {
self.clauses.iter().cloned()
}
}