compiler/rustc_ty_utils/src/implied_bounds.rs

   1 use crate::rustc_middle::ty::DefIdTree;
   2 use rustc_hir::{def::DefKind, def_id::DefId};
   3 use rustc_middle::ty::{self, Ty, TyCtxt};
   4
   5 pub fn provide(providers: &mut ty::query::Providers) {
   6     *providers = ty::query::Providers { assumed_wf_types, ..*providers };
   7 }
   8
   9 fn assumed_wf_types(tcx: TyCtxt<'_>, def_id: DefId) -> &ty::List<Ty<'_>> {
  10     match tcx.def_kind(def_id) {
  11         DefKind::Fn => {
  12             let sig = tcx.fn_sig(def_id);
  13             let liberated_sig = tcx.liberate_late_bound_regions(def_id, sig);
  14             liberated_sig.inputs_and_output
  15         }
  16         DefKind::AssocFn => {
  17             let sig = tcx.fn_sig(def_id);
  18             let liberated_sig = tcx.liberate_late_bound_regions(def_id, sig);
  19             let mut assumed_wf_types: Vec<_> =
  20                 tcx.assumed_wf_types(tcx.parent(def_id)).as_slice().into();
  21             assumed_wf_types.extend(liberated_sig.inputs_and_output);
  22             tcx.intern_type_list(&assumed_wf_types)
  23         }
  24         DefKind::Impl => {
  25             match tcx.impl_trait_ref(def_id) {
  26                 Some(trait_ref) => {
  27                     let types: Vec<_> = trait_ref.skip_binder().substs.types().collect();
  28                     tcx.intern_type_list(&types)
  29                 }
  30                 // Only the impl self type
  31                 None => tcx.intern_type_list(&[tcx.type_of(def_id)]),
  32             }
  33         }
  34         DefKind::AssocConst | DefKind::AssocTy => tcx.assumed_wf_types(tcx.parent(def_id)),
  35         DefKind::Mod
  36         | DefKind::Struct
  37         | DefKind::Union
  38         | DefKind::Enum
  39         | DefKind::Variant
  40         | DefKind::Trait
  41         | DefKind::TyAlias
  42         | DefKind::ForeignTy
  43         | DefKind::TraitAlias
  44         | DefKind::TyParam
  45         | DefKind::Const
  46         | DefKind::ConstParam
  47         | DefKind::Static(_)
  48         | DefKind::Ctor(_, _)
  49         | DefKind::Macro(_)
  50         | DefKind::ExternCrate
  51         | DefKind::Use
  52         | DefKind::ForeignMod
  53         | DefKind::AnonConst
  54         | DefKind::InlineConst
  55         | DefKind::OpaqueTy
  56         | DefKind::ImplTraitPlaceholder
  57         | DefKind::Field
  58         | DefKind::LifetimeParam
  59         | DefKind::GlobalAsm
  60         | DefKind::Closure
  61         | DefKind::Generator => ty::List::empty(),
  62     }
  63 }