Pack Term in the same way as GenericArg.

This shrinks the `PredicateS` type, which is instanted frequently.

Author: nnethercote

clippy_lints/src/dereference.rs

@@ -1174,7 +1174,7 @@ fn replace_types<'tcx>(
         if replaced.insert(param_ty.index) {
             for projection_predicate in projection_predicates {
                 if projection_predicate.projection_ty.self_ty() == param_ty.to_ty(cx.tcx)
-                    && let ty::Term::Ty(term_ty) = projection_predicate.term
+                    && let Some(term_ty) = projection_predicate.term.ty()
                     && let ty::Param(term_param_ty) = term_ty.kind()
                 {
                     let item_def_id = projection_predicate.projection_ty.item_def_id;

clippy_lints/src/methods/mod.rs

@@ -3302,9 +3302,9 @@ impl<'tcx> LateLintPass<'tcx> for Methods {
                 // one of the associated types must be Self
                 for &(predicate, _span) in cx.tcx.explicit_item_bounds(def_id) {
                     if let ty::PredicateKind::Projection(projection_predicate) = predicate.kind().skip_binder() {
-                        let assoc_ty = match projection_predicate.term {
-                            ty::Term::Ty(ty) => ty,
-                            ty::Term::Const(_c) => continue,
+                        let assoc_ty = match projection_predicate.term.unpack() {
+                            ty::TermKind::Ty(ty) => ty,
+                            ty::TermKind::Const(_c) => continue,
                         };
                         // walk the associated type and check for Self
                         if let Some(self_adt) = self_ty.ty_adt_def() {

clippy_lints/src/methods/unnecessary_to_owned.rs

@@ -268,7 +268,7 @@ fn check_other_call_arg<'tcx>(
                         .subst_and_normalize_erasing_regions(call_substs, cx.param_env, projection_predicate.term);
                 implements_trait(cx, receiver_ty, deref_trait_id, &[])
                     && get_associated_type(cx, receiver_ty, deref_trait_id, "Target")
-                        .map_or(false, |ty| ty::Term::Ty(ty) == normalized_ty)
+                        .map_or(false, |ty| ty::TermKind::Ty(ty) == normalized_ty.unpack())
             } else {
                 false
             }