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Simplify instantiate_poly_trait_ref

This commit is contained in:
Michael Goulet 2023-11-23 05:34:29 +00:00
parent fc010de26b
commit 653ca5ad3b

View file

@ -675,36 +675,57 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
)
}
fn instantiate_poly_trait_ref_inner(
/// Given a trait bound like `Debug`, applies that trait bound the given self-type to construct
/// a full trait reference. The resulting trait reference is returned. This may also generate
/// auxiliary bounds, which are added to `bounds`.
///
/// Example:
///
/// ```ignore (illustrative)
/// poly_trait_ref = Iterator<Item = u32>
/// self_ty = Foo
/// ```
///
/// this would return `Foo: Iterator` and add `<Foo as Iterator>::Item = u32` into `bounds`.
///
/// **A note on binders:** against our usual convention, there is an implied binder around
/// the `self_ty` and `poly_trait_ref` parameters here. So they may reference bound regions.
/// If for example you had `for<'a> Foo<'a>: Bar<'a>`, then the `self_ty` would be `Foo<'a>`
/// where `'a` is a bound region at depth 0. Similarly, the `poly_trait_ref` would be
/// `Bar<'a>`. The returned poly-trait-ref will have this binder instantiated explicitly,
/// however.
#[instrument(level = "debug", skip(self, span, constness, bounds, speculative))]
pub(crate) fn instantiate_poly_trait_ref(
&self,
hir_id: hir::HirId,
trait_ref: &hir::TraitRef<'_>,
span: Span,
binding_span: Option<Span>,
constness: ty::BoundConstness,
polarity: ty::ImplPolarity,
self_ty: Ty<'tcx>,
bounds: &mut Bounds<'tcx>,
speculative: bool,
trait_ref_span: Span,
trait_def_id: DefId,
trait_segment: &hir::PathSegment<'_>,
args: &GenericArgs<'_>,
infer_args: bool,
self_ty: Ty<'tcx>,
only_self_bounds: OnlySelfBounds,
) -> GenericArgCountResult {
let trait_def_id = trait_ref.trait_def_id().unwrap_or_else(|| FatalError.raise());
let trait_segment = trait_ref.path.segments.last().unwrap();
let args = trait_segment.args();
self.prohibit_generics(trait_ref.path.segments.split_last().unwrap().1.iter(), |_| {});
self.complain_about_internal_fn_trait(span, trait_def_id, trait_segment, false);
let (generic_args, arg_count) = self.create_args_for_ast_path(
trait_ref_span,
trait_ref.path.span,
trait_def_id,
&[],
trait_segment,
args,
infer_args,
trait_segment.infer_args,
Some(self_ty),
constness,
);
let tcx = self.tcx();
let bound_vars = tcx.late_bound_vars(hir_id);
let bound_vars = tcx.late_bound_vars(trait_ref.hir_ref_id);
debug!(?bound_vars);
let assoc_bindings = self.create_assoc_bindings_for_generic_args(args);
@ -732,13 +753,13 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
// Specify type to assert that error was already reported in `Err` case.
let _: Result<_, ErrorGuaranteed> = self.add_predicates_for_ast_type_binding(
hir_id,
trait_ref.hir_ref_id,
poly_trait_ref,
binding,
bounds,
speculative,
&mut dup_bindings,
binding_span.unwrap_or(binding.span),
binding.span,
constness,
only_self_bounds,
polarity,
@ -749,67 +770,6 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
arg_count
}
/// Given a trait bound like `Debug`, applies that trait bound the given self-type to construct
/// a full trait reference. The resulting trait reference is returned. This may also generate
/// auxiliary bounds, which are added to `bounds`.
///
/// Example:
///
/// ```ignore (illustrative)
/// poly_trait_ref = Iterator<Item = u32>
/// self_ty = Foo
/// ```
///
/// this would return `Foo: Iterator` and add `<Foo as Iterator>::Item = u32` into `bounds`.
///
/// **A note on binders:** against our usual convention, there is an implied bounder around
/// the `self_ty` and `poly_trait_ref` parameters here. So they may reference bound regions.
/// If for example you had `for<'a> Foo<'a>: Bar<'a>`, then the `self_ty` would be `Foo<'a>`
/// where `'a` is a bound region at depth 0. Similarly, the `poly_trait_ref` would be
/// `Bar<'a>`. The returned poly-trait-ref will have this binder instantiated explicitly,
/// however.
#[instrument(level = "debug", skip(self, span, constness, bounds, speculative))]
pub(crate) fn instantiate_poly_trait_ref(
&self,
trait_ref: &hir::TraitRef<'_>,
span: Span,
constness: ty::BoundConstness,
polarity: ty::ImplPolarity,
self_ty: Ty<'tcx>,
bounds: &mut Bounds<'tcx>,
speculative: bool,
only_self_bounds: OnlySelfBounds,
) -> GenericArgCountResult {
let hir_id = trait_ref.hir_ref_id;
let binding_span = None;
let trait_ref_span = trait_ref.path.span;
let trait_def_id = trait_ref.trait_def_id().unwrap_or_else(|| FatalError.raise());
let trait_segment = trait_ref.path.segments.last().unwrap();
let args = trait_segment.args();
let infer_args = trait_segment.infer_args;
self.prohibit_generics(trait_ref.path.segments.split_last().unwrap().1.iter(), |_| {});
self.complain_about_internal_fn_trait(span, trait_def_id, trait_segment, false);
// TODO: inline
self.instantiate_poly_trait_ref_inner(
hir_id,
span,
binding_span,
constness,
polarity,
bounds,
speculative,
trait_ref_span,
trait_def_id,
trait_segment,
args,
infer_args,
self_ty,
only_self_bounds,
)
}
fn ast_path_to_mono_trait_ref(
&self,
span: Span,