'Test the formatting of EngFormatter with some inputs, against
instances with and without units. Cases focus on when no SI
prefix is present, for values in [1, 1000).'

@pytest.mark.parametrize(u'unit,    input,    expected', format_data)
def test_formatting(self, unit, input, expected):

    fmt = mticker.EngFormatter(unit)
    assert (fmt(input) == expected)
