RSpec.describe Mutant::Integration do let(:class_under_test) do Class.new(described_class) end let(:object) { class_under_test.new } describe '#setup' do subject { object.setup } it_should_behave_like 'a command method' end end RSpec.describe Mutant::Integration::Null do let(:object) { described_class.new } describe '#setup' do subject { object.all_tests } it { should eql([]) } it_should_behave_like 'an idempotent method' end end