def METHOD_NAME():
    """
    Test assertion that are not tested directly with plots.
    """
    data = pf.Signal([1, 0, 0], 44100)
    kwargs = {"shading": "flat"}
    # assertion for data type
    with raises(TypeError, match="Input data has to be of type"):
        plot._utils._prepare_2d_plot(
            data, (pf.FrequencyData, ), 1, [0], 'pcolormesh', plt.gca(), False)
    # assertion for shading
    with raises(ValueError, match="shading is 'flat' but must be 'nearest'"):
        plot._utils._prepare_2d_plot(
            data, (pf.Signal, ), 1, [0], 'pcolormesh', plt.gca(), False,
            **kwargs)
    # assertion for indices
    with raises(ValueError, match="length of indices must match"):
        plot._utils._prepare_2d_plot(
            data, (pf.Signal, ), 1, [0, 1], 'pcolormesh', plt.gca(), False)
    # assertion for method
    with raises(ValueError, match="method must be"):
        plot._utils._prepare_2d_plot(
            data, (pf.Signal, ), 1, [0], 'pcontourmesh', plt.gca(), False)