@Override
    public boolean isEmpty() {
        return size() == 0;
    }
@Test
    public void shouldReturnFalseSomePartIsNotEmpty() {
        PipelineConfigs group = new MergePipelineConfigs(
                new BasicPipelineConfigs(PipelineConfigMother.pipelineConfig("pipeline1")),
                new BasicPipelineConfigs());
        assertThat(group.isEmpty(), is(false));
    }