require 'spec_helper' describe Virtus::Attribute, '#defined?' do subject { object.defined?(instance) } let(:object) { described_class.build(String, :name => name) } let(:model) { Class.new { attr_accessor :test } } let(:name) { :test } let(:instance) { model.new } context 'when the attribute value has not been defined' do it { is_expected.to be(false) } end context 'when the attribute value has been defined' do before { instance.test = nil } it { is_expected.to be(true) } end end