def test_filtfilt():
    x = np.r_[1, np.zeros(100)]
    # Filter with an impulse
    y = mne_filtfilt([1, 0], [1, 0], x, padlen=0)
    assert_array_equal(x, y)
Test IIR filtfilt replacement
dataset/ETHPy150Open mne-tools/mne-python/mne/tests/test_fixes.py/test_filtfilt