add trait aliases to typeck

Author: durka

src/librustc/ty/mod.rs

@@ -2577,6 +2577,7 @@ fn associated_item_def_ids<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
  .map(|id| tcx.hir.local_def_id(id.node_id))
  .collect()
  }
+ hir::ItemTraitAlias(..) => vec![],
  _ => span_bug!(item.span, "associated_item_def_ids: not impl or trait")
  };
  Rc::new(vec)

src/librustc_typeck/astconv.rs

@@ -336,6 +336,7 @@ impl<'o, 'gcx: 'tcx, 'tcx> AstConv<'gcx, 'tcx>+'o {
  let path = &trait_ref.path;
  match path.def {
  Def::Trait(trait_def_id) => trait_def_id,
+ Def::TraitAlias(alias_def_id) => alias_def_id,
  Def::Err => {
  self.tcx().sess.fatal("cannot continue compilation due to previous error");
  }

src/librustc_typeck/collect.rs

@@ -441,6 +441,11 @@ fn convert_item<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>, item_id: ast::NodeId) {
  tcx.at(it.span).super_predicates_of(def_id);
  tcx.predicates_of(def_id);
  },
+ hir::ItemTraitAlias(..) => {
+ tcx.generics_of(def_id);
+ tcx.trait_def(def_id);
+ tcx.predicates_of(def_id);
+ },
  hir::ItemStruct(ref struct_def, _) |
  hir::ItemUnion(ref struct_def, _) => {
  tcx.generics_of(def_id);
@@ -672,6 +677,7 @@ fn super_predicates_of<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
 
  let (generics, bounds) = match item.node {
  hir::ItemTrait(.., ref generics, ref supertraits, _) => (generics, supertraits),
+ hir::ItemTraitAlias(ref generics, ref supertraits) => (generics, supertraits),
  _ => span_bug!(item.span,
  "super_predicates invoked on non-trait"),
  };
@@ -715,6 +721,7 @@ fn trait_def<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
 
  let unsafety = match item.node {
  hir::ItemTrait(_, unsafety, ..) => unsafety,
+ hir::ItemTraitAlias(..) => hir::Unsafety::Normal,
  _ => span_bug!(item.span, "trait_def_of_item invoked on non-trait"),
  };
 
@@ -902,7 +909,7 @@ fn generics_of<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
  (generics, None)
  }
 
- ItemTrait(_, _, ref generics, ..) => {
+ ItemTrait(_, _, ref generics, ..) | ItemTraitAlias(ref generics, ..) => {
  // Add in the self type parameter.
  //
  // Something of a hack: use the node id for the trait, also as
@@ -1132,7 +1139,7 @@ fn type_of<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
  tcx.mk_adt(def, substs)
  }
  ItemAutoImpl(..) |
- ItemTrait(..) |
+ ItemTrait(..) | ItemTraitAlias(..) |
  ItemMod(..) |
  ItemForeignMod(..) |
  ItemGlobalAsm(..) |