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Move has_structural_eq_impls provider to rustc_ty_utils

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This commit is contained in:
Michael Goulet 2022-12-08 04:02:50 +00:00
parent 01fbc5ae78
commit 48270044b0
4 changed files with 46 additions and 49 deletions
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1
compiler/rustc_trait_selection/src/traits/mod.rs
View file

@ -922,7 +922,6 @@ pub fn vtable_trait_upcasting_coercion_new_vptr_slot<'tcx>(
pub fn provide(providers: &mut ty::query::Providers) {
object_safety::provide(providers);
structural_match::provide(providers);
*providers = ty::query::Providers {
specialization_graph_of: specialize::specialization_graph_provider,
specializes: specialize::specializes,

48
compiler/rustc_trait_selection/src/traits/structural_match.rs
View file

@ -1,10 +1,5 @@
use crate::infer::{InferCtxt, TyCtxtInferExt};
use crate::traits::{ObligationCause, ObligationCtxt};
use rustc_data_structures::fx::FxHashSet;
use rustc_hir as hir;
use rustc_hir::lang_items::LangItem;
use rustc_middle::ty::query::Providers;
use rustc_middle::ty::{self, Ty, TyCtxt, TypeSuperVisitable, TypeVisitable, TypeVisitor};
use rustc_span::Span;
use std::ops::ControlFlow;
@ -59,41 +54,6 @@ pub fn search_for_adt_const_param_violation<'tcx>(
.break_value()
}
/// This method returns true if and only if `adt_ty` itself has been marked as
/// eligible for structural-match: namely, if it implements both
/// `StructuralPartialEq` and `StructuralEq` (which are respectively injected by
/// `#[derive(PartialEq)]` and `#[derive(Eq)]`).
///
/// Note that this does *not* recursively check if the substructure of `adt_ty`
/// implements the traits.
fn type_marked_structural<'tcx>(
infcx: &InferCtxt<'tcx>,
adt_ty: Ty<'tcx>,
cause: ObligationCause<'tcx>,
) -> bool {
let ocx = ObligationCtxt::new(infcx);
// require `#[derive(PartialEq)]`
let structural_peq_def_id =
infcx.tcx.require_lang_item(LangItem::StructuralPeq, Some(cause.span));
ocx.register_bound(cause.clone(), ty::ParamEnv::empty(), adt_ty, structural_peq_def_id);
// for now, require `#[derive(Eq)]`. (Doing so is a hack to work around
// the type `for<'a> fn(&'a ())` failing to implement `Eq` itself.)
let structural_teq_def_id =
infcx.tcx.require_lang_item(LangItem::StructuralTeq, Some(cause.span));
ocx.register_bound(cause, ty::ParamEnv::empty(), adt_ty, structural_teq_def_id);
// We deliberately skip *reporting* fulfillment errors (via
// `report_fulfillment_errors`), for two reasons:
//
// 1. The error messages would mention `std::marker::StructuralPartialEq`
// (a trait which is solely meant as an implementation detail
// for now), and
//
// 2. We are sometimes doing future-incompatibility lints for
// now, so we do not want unconditional errors here.
ocx.select_all_or_error().is_empty()
}
/// This implements the traversal over the structure of a given type to try to
/// find instances of ADTs (specifically structs or enums) that do not implement
/// the structural-match traits (`StructuralPartialEq` and `StructuralEq`).
@ -249,11 +209,3 @@ impl<'tcx> TypeVisitor<'tcx> for Search<'tcx> {
})
}
}
pub fn provide(providers: &mut Providers) {
providers.has_structural_eq_impls = |tcx, ty| {
let infcx = tcx.infer_ctxt().build();
let cause = ObligationCause::dummy();
type_marked_structural(&infcx, ty, cause)
};
}