def test_display_set():
mock = HcsMock()
hcs = HcsCom(port=mock)
volt = 12
hcs.set_voltage(volt)
assert mock.display_values[0] == volt
curr = 5
hcs.set_current(curr)
assert mock.display_values[1] == curr
def test_display_set_format_four_digits():
mock = HcsMock()
mock.set_format(FORMAT_FOUR_DIGITS)
hcs = HcsCom(port=mock)
assert hcs.value_format == FORMAT_FOUR_DIGITS
volt = 12
hcs.set_voltage(volt)
assert mock.display_values[0] == volt
curr = 5
hcs.set_current(curr)
assert mock.display_values[1] == curr