class Xcodeproj::Project::Object::AbstractObject

def attributes
  unless @full_attributes
    attributes = @attributes || []
    super_attributes = superclass.respond_to?(:attributes) ? superclass.attributes : []
    # The uniqueness of the attributes is very important because the
    # initialization from plist deletes the values from the dictionary.
    @full_attributes = attributes.concat(super_attributes).uniq
  end
  @full_attributes
end