def METHOD_NAME(df):
    """
    Test case_when for scenarios where `default` is an index.
    """
    default = range(len(df))
    result = df.case_when(
        "numbers > 1",
        lambda df: df.numbers + 10,
        default=pd.Index(default),
        column_name="bleh",
    )
    expected = np.where(df.numbers > 1, df.numbers + 10, default)
    expected = df.assign(bleh=expected)
    assert_frame_equal(result, expected)