rustc_ty_utils/
common_traits.rs

1//! Queries for checking whether a type implements one of a few common traits.
2
3use rustc_hir::lang_items::LangItem;
4use rustc_infer::infer::TyCtxtInferExt;
5use rustc_middle::query::Providers;
6use rustc_middle::ty::{self, Ty, TyCtxt};
7use rustc_trait_selection::traits;
8
9fn is_copy_raw<'tcx>(tcx: TyCtxt<'tcx>, query: ty::PseudoCanonicalInput<'tcx, Ty<'tcx>>) -> bool {
10    is_item_raw(tcx, query, LangItem::Copy)
11}
12
13fn is_use_cloned_raw<'tcx>(
14    tcx: TyCtxt<'tcx>,
15    query: ty::PseudoCanonicalInput<'tcx, Ty<'tcx>>,
16) -> bool {
17    is_item_raw(tcx, query, LangItem::UseCloned)
18}
19
20fn is_sized_raw<'tcx>(tcx: TyCtxt<'tcx>, query: ty::PseudoCanonicalInput<'tcx, Ty<'tcx>>) -> bool {
21    is_item_raw(tcx, query, LangItem::Sized)
22}
23
24fn is_freeze_raw<'tcx>(tcx: TyCtxt<'tcx>, query: ty::PseudoCanonicalInput<'tcx, Ty<'tcx>>) -> bool {
25    is_item_raw(tcx, query, LangItem::Freeze)
26}
27
28fn is_unpin_raw<'tcx>(tcx: TyCtxt<'tcx>, query: ty::PseudoCanonicalInput<'tcx, Ty<'tcx>>) -> bool {
29    is_item_raw(tcx, query, LangItem::Unpin)
30}
31
32fn is_async_drop_raw<'tcx>(
33    tcx: TyCtxt<'tcx>,
34    query: ty::PseudoCanonicalInput<'tcx, Ty<'tcx>>,
35) -> bool {
36    is_item_raw(tcx, query, LangItem::AsyncDrop)
37}
38
39fn is_item_raw<'tcx>(
40    tcx: TyCtxt<'tcx>,
41    query: ty::PseudoCanonicalInput<'tcx, Ty<'tcx>>,
42    item: LangItem,
43) -> bool {
44    let (infcx, param_env) = tcx.infer_ctxt().build_with_typing_env(query.typing_env);
45    let trait_def_id = tcx.require_lang_item(item, None);
46    traits::type_known_to_meet_bound_modulo_regions(&infcx, param_env, query.value, trait_def_id)
47}
48
49pub(crate) fn provide(providers: &mut Providers) {
50    *providers = Providers {
51        is_copy_raw,
52        is_use_cloned_raw,
53        is_sized_raw,
54        is_freeze_raw,
55        is_unpin_raw,
56        is_async_drop_raw,
57        ..*providers
58    };
59}