:as option doesn't play well with SearchObject

lib/search_object/plugin/graphql.rb

@@ -76,7 +76,6 @@ def build_argument(name, options)
           argument.type = options.fetch(:type) { raise MissingTypeDefinitionError, name }
           argument.default_value = options[:default] if options.key? :default
           argument.description = options[:description] if options.key? :description
-          argument.as = options[:as] if options.key? :as
           argument
         end
       end

spec/search_object/plugin/graphql_spec.rb

@@ -222,8 +222,26 @@ def define_search_class(&block)
       expect { define_search_class { option :name } }.to raise_error described_class::MissingTypeDefinitionError
     end
 
-    it 'accepts default type'
-    it 'accepts as'
+    it 'accepts default type' do
+      search_object = define_search_class do
+        scope { [] }
+
+        option(:id, type: types.String, default: 'default') do |_scope, value|
+          [Post.new(value)]
+        end
+      end
+
+      result = execute_query_on_schema('{ posts { id } }') do
+        field :posts, types[PostType], function: search_object
+      end
+
+      expect(result).to eq(
+        'data' => {
+          'posts' => [Post.new('default').to_json]
+        }
+      )
+    end
+
     it 'accepts description'
   end
 end