def test_overlay_array_bad_type():
    plot = SigPlot()
    assert plot.inputs == []

    data = 3
    with pytest.raises(TypeError):
        plot.overlay_array(data)
def test_overlay_array_non_empty():
    plot = SigPlot()
    assert plot.inputs == []

    data = [1, 2, 3]
    plot.overlay_array(data)
    assert plot.inputs == [data]