@pytest.mark.parametrize("label_propagation_class",
                         [label_propagation.LabelSpreading,
                          label_propagation.LabelPropagation])
def test_label_propagation_non_zero_normalizer(label_propagation_class):
    # check that we don't divide by zero in case of null normalizer
    # non-regression test for
    # https://github.com/scikit-learn/scikit-learn/pull/15946
    # https://github.com/scikit-learn/scikit-learn/pull/19271
    X = np.array([[100., 100.], [100., 100.], [0., 0.], [0., 0.]])
    y = np.array([0, 1, -1, -1])
    mdl = label_propagation_class(kernel='knn',
                                  max_iter=100,
                                  n_neighbors=1)
    assert_no_warnings(mdl.fit, X, y)