{"ast_node_type":"impl","tokens":[{"end":52,"kind":"keyword","start":0,"text":"//"}]}
                // Check for desugared `impl Trait`.
            Res::Def(DefKind::OpaqueTy, did) => {
                assert_matches!(tcx.opaque_ty_origin(did), hir::OpaqueTyOrigin::TyAlias { .. });