@pytest.mark.parametrize('n', [-1, 0, 1])
def test_shift_arithmetic(sql, n):
    t = symbol('t', discover(sql))
    expr = t.B - t.B.shift(n)
    result = compute(expr, sql, return_type=pd.Series)
    df = odo(sql, pd.DataFrame)
    expected = df.B - df.B.shift(n)
    tm.assert_series_equal(result, expected)
dataset/ETHPy150Open blaze/blaze/blaze/compute/tests/test_postgresql_compute.py/test_shift_arithmetic/original