Fix: broken binding generation when unexposed enum in struct field

Fixes crystal-lang#66

spec/parser_spec.cr

@@ -89,6 +89,15 @@ describe Parser do
     fields.first.type.should eq(PointerType.new(UnexposedType.new("foo")))
   end
 
+  it "parses struct with unexposed enum" do
+    nodes = parse("struct point { enum { x, y } foo;  };")
+    type = nodes.last.as(StructOrUnion)
+    fields = type.fields
+    node_ref = fields.first.type.as(NodeRef)
+    enum_def = node_ref.node.as(CrystalLib::Enum)
+    enum_def.values.size.should eq(2)
+  end
+
   it "parses recursive struct" do
     nodes = parse("struct point { struct point* x; };")
     type = nodes.last.as(StructOrUnion)

src/crystal_lib/parser.cr

@@ -267,6 +267,8 @@ class CrystalLib::Parser
           NodeRef.new(visit_struct_or_union_declaration(definition, :struct))
         when .union_decl?
           NodeRef.new(visit_struct_or_union_declaration(definition, :union))
+        when .enum_decl?
+          NodeRef.new(visit_enum_declaration(definition))
         else
           UnexposedType.new(type.cursor.spelling)
         end