def test_plot_corner(results_to_test):
    """
    Tests plot_corner() with plotting simulated posterior samples
    for all 8 parameters and for just four selected parameters
    """
    Figure1 = results_to_test.plot_corner()
    assert Figure1 is not None
    Figure2 = results_to_test.plot_corner(param_list=['sma1', 'ecc1', 'inc1', 'mtot'])
    assert Figure2 is not None
    return Figure1, Figure2