def test_arithmetic_on_small_array_from_file(file):
    s = symbol('s', discover(file))

    assert eq(compute(s.x + 1, file),
              x + 1)
Want to make sure that we call pre_compute on Dataset
dataset/ETHPy150Open blaze/blaze/blaze/compute/tests/test_h5py.py/test_arithmetic_on_small_array_from_file