Make TypeBoundPredicate a subclass of the SubstitutionRef

This will allow us to reuse our generic substitions code to manage generic
traits and their substitions better. It will unify the handling in one
path so we get the same error handling.

7 files changed, 75 insertions, 19 deletions

diff --git a/gcc/rust/typecheck/rust-hir-trait-ref.h b/gcc/rust/typecheck/rust-hir-trait-ref.h
index 4ad0d7b..585fb6c 100644
--- a/gcc/rust/typecheck/rust-hir-trait-ref.h
+++ b/gcc/rust/typecheck/rust-hir-trait-ref.h
@@ -407,7 +407,7 @@ public:
 
   bool trait_has_generics () const { return !trait_substs.empty (); }
 
-  const std::vector<TyTy::SubstitutionParamMapping> &get_trait_substs () const
+  std::vector<TyTy::SubstitutionParamMapping> get_trait_substs () const
   {
     return trait_substs;
   }
diff --git a/gcc/rust/typecheck/rust-hir-trait-resolve.h b/gcc/rust/typecheck/rust-hir-trait-resolve.h
index 7af353a..806a46f 100644
--- a/gcc/rust/typecheck/rust-hir-trait-resolve.h
+++ b/gcc/rust/typecheck/rust-hir-trait-resolve.h
@@ -150,8 +150,13 @@ private:
 
     // They also inherit themselves as a bound this enables a trait item to
     // reference other Self::trait_items
+    std::vector<TyTy::SubstitutionParamMapping> self_subst_copy;
+    for (auto &sub : substitutions)
+      self_subst_copy.push_back (sub.clone ());
+
     specified_bounds.push_back (
       TyTy::TypeBoundPredicate (trait_reference->get_mappings ().get_defid (),
+				std::move (self_subst_copy),
 				trait_reference->get_locus ()));
 
     std::vector<const TraitReference *> super_traits;
@@ -168,8 +173,8 @@ private:
 		// FIXME this might be recursive we need a check for that
 
 		TraitReference *trait = resolve_trait_path (b->get_path ());
-		TyTy::TypeBoundPredicate predicate (
-		  trait->get_mappings ().get_defid (), bound->get_locus ());
+		TyTy::TypeBoundPredicate predicate (*trait,
+						    bound->get_locus ());
 
 		specified_bounds.push_back (std::move (predicate));
 		super_traits.push_back (predicate.get ());
diff --git a/gcc/rust/typecheck/rust-hir-type-check-item.h b/gcc/rust/typecheck/rust-hir-type-check-item.h
index f86e967..8a41548 100644
--- a/gcc/rust/typecheck/rust-hir-type-check-item.h
+++ b/gcc/rust/typecheck/rust-hir-type-check-item.h
@@ -79,8 +79,8 @@ public:
 	rust_assert (!trait_reference->is_error ());
 
 	// setup the bound
-	TyTy::TypeBoundPredicate predicate (
-	  trait_reference->get_mappings ().get_defid (), ref->get_locus ());
+	TyTy::TypeBoundPredicate predicate (*trait_reference,
+					    ref->get_locus ());
 	auto &final_seg = ref->get_final_segment ();
 	if (final_seg->is_generic_segment ())
 	  {
diff --git a/gcc/rust/typecheck/rust-hir-type-check-type.cc b/gcc/rust/typecheck/rust-hir-type-check-type.cc
index 6c6546b..ee77128 100644
--- a/gcc/rust/typecheck/rust-hir-type-check-type.cc
+++ b/gcc/rust/typecheck/rust-hir-type-check-type.cc
@@ -550,8 +550,7 @@ TypeCheckType::visit (HIR::TraitObjectType &type)
 
       auto &type_path = trait_bound.get_path ();
       TraitReference *trait = resolve_trait_path (type_path);
-      TyTy::TypeBoundPredicate predicate (trait->get_mappings ().get_defid (),
-					  trait_bound.get_locus ());
+      TyTy::TypeBoundPredicate predicate (*trait, trait_bound.get_locus ());
       auto &final_seg = type_path.get_final_segment ();
       if (final_seg->is_generic_segment ())
 	{
diff --git a/gcc/rust/typecheck/rust-hir-type-check-type.h b/gcc/rust/typecheck/rust-hir-type-check-type.h
index e037562..373287e 100644
--- a/gcc/rust/typecheck/rust-hir-type-check-type.h
+++ b/gcc/rust/typecheck/rust-hir-type-check-type.h
@@ -247,8 +247,7 @@ public:
 
 		  auto &type_path = b->get_path ();
 		  TraitReference *trait = resolve_trait_path (type_path);
-		  TyTy::TypeBoundPredicate predicate (
-		    trait->get_mappings ().get_defid (), b->get_locus ());
+		  TyTy::TypeBoundPredicate predicate (*trait, b->get_locus ());
 
 		  auto &final_seg = type_path.get_final_segment ();
 		  if (final_seg->is_generic_segment ())
@@ -318,8 +317,7 @@ public:
 
 	      auto &type_path = b->get_path ();
 	      TraitReference *trait = resolve_trait_path (type_path);
-	      TyTy::TypeBoundPredicate predicate (
-		trait->get_mappings ().get_defid (), b->get_locus ());
+	      TyTy::TypeBoundPredicate predicate (*trait, b->get_locus ());
 
 	      auto &final_seg = type_path.get_final_segment ();
 	      if (final_seg->is_generic_segment ())
diff --git a/gcc/rust/typecheck/rust-tyty-bounds.cc b/gcc/rust/typecheck/rust-tyty-bounds.cc
index bc1e76e..25d4966 100644
--- a/gcc/rust/typecheck/rust-tyty-bounds.cc
+++ b/gcc/rust/typecheck/rust-tyty-bounds.cc
@@ -67,17 +67,38 @@ TypeCheckBase::resolve_trait_path (HIR::TypePath &path)
 
 namespace TyTy {
 
-TypeBoundPredicate::TypeBoundPredicate (DefId reference, Location locus)
-  : reference (reference), locus (locus), args (nullptr)
+TypeBoundPredicate::TypeBoundPredicate (
+  const Resolver::TraitReference &trait_reference, Location locus)
+  : SubstitutionRef (trait_reference.get_trait_substs (),
+		     SubstitutionArgumentMappings::error ()),
+    reference (trait_reference.get_mappings ().get_defid ()), locus (locus),
+    args (nullptr), error_flag (false)
 {}
 
+TypeBoundPredicate::TypeBoundPredicate (
+  DefId reference, std::vector<SubstitutionParamMapping> substitutions,
+  Location locus)
+  : SubstitutionRef (std::move (substitutions),
+		     SubstitutionArgumentMappings::error ()),
+    reference (reference), locus (locus), args (nullptr), error_flag (false)
+{}
+
+TypeBoundPredicate::TypeBoundPredicate (const TypeBoundPredicate &other)
+  : SubstitutionRef ({}, other.used_arguments), reference (other.reference),
+    locus (other.locus), args (other.args), error_flag (other.error_flag)
+{
+  substitutions.clear ();
+  if (!other.is_error ())
+    {
+      for (const auto &p : other.get_substs ())
+	substitutions.push_back (p.clone ());
+    }
+}
+
 std::string
 TypeBoundPredicate::as_string () const
 {
-  return get ()->as_string ()
-	 + (has_generic_args ()
-	      ? std::string ("<") + args->as_string () + std::string (">")
-	      : "");
+  return get ()->as_string () + subst_as_string ();
 }
 
 const Resolver::TraitReference *
@@ -183,6 +204,25 @@ TypeBoundPredicateItem::get_tyty_for_receiver (
 
   return resolved;
 }
+bool
+TypeBoundPredicate::is_error () const
+{
+  auto context = Resolver::TypeCheckContext::get ();
+
+  Resolver::TraitReference *ref = nullptr;
+  bool ok = context->lookup_trait_reference (reference, &ref);
+
+  return !ok || error_flag;
+}
+
+BaseType *
+TypeBoundPredicate::handle_substitions (SubstitutionArgumentMappings mappings)
+{
+  gcc_unreachable ();
+  return nullptr;
+}
+
+// trait item reference
 
 const Resolver::TraitItemReference *
 TypeBoundPredicateItem::get_raw_item () const
diff --git a/gcc/rust/typecheck/rust-tyty.h b/gcc/rust/typecheck/rust-tyty.h
index d1c2170..44eb81f 100644
--- a/gcc/rust/typecheck/rust-tyty.h
+++ b/gcc/rust/typecheck/rust-tyty.h
@@ -939,10 +939,17 @@ protected:
   SubstitutionArgumentMappings used_arguments;
 };
 
-class TypeBoundPredicate
+class TypeBoundPredicate : public SubstitutionRef
 {
 public:
-  TypeBoundPredicate (DefId reference, Location locus);
+  TypeBoundPredicate (const Resolver::TraitReference &trait_reference,
+		      Location locus);
+
+  TypeBoundPredicate (DefId reference,
+		      std::vector<SubstitutionParamMapping> substitutions,
+		      Location locus);
+
+  TypeBoundPredicate (const TypeBoundPredicate &other);
 
   std::string as_string () const;
 
@@ -975,10 +982,17 @@ public:
     return args->has_generic_args ();
   }
 
+  // WARNING THIS WILL ALWAYS RETURN NULLPTR
+  BaseType *
+  handle_substitions (SubstitutionArgumentMappings mappings) override final;
+
+  bool is_error () const;
+
 private:
   DefId reference;
   Location locus;
   HIR::GenericArgs *args;
+  bool error_flag;
 };
 
 // https://doc.rust-lang.org/nightly/nightly-rustc/rustc_middle/ty/struct.VariantDef.html