def test_modifierbuttons_empty():
# Tests the initial state of a ModifierButtons object.
btns = ModifierButtons()
assert btns == ModifierButtons(btns)
assert btns != ModifierButtons()
assert btns.matches(ModifierButtons())
assert not btns.is_down("alt")
assert not btns.is_any_down()
assert not btns.has_button("alt")
assert btns.get_prefix() == ""
assert btns.get_num_buttons() == 0
assert len(btns.buttons) == 0
def test_modifierbuttons_state():
btns = ModifierButtons()
btns.add_button("alt")
btns.add_button("shift")
btns.add_button("control")
assert not btns.is_any_down()
# Not tracked
btns.button_down("enter")
assert not btns.is_any_down()
# Tracked
btns.button_down("shift")
assert btns.is_any_down()
assert not btns.is_down(0)
assert btns.is_down(1)
assert not btns.is_down(2)
btns.button_up("shift")
assert not btns.is_any_down()
assert not btns.is_down(0)
assert not btns.is_down(1)
assert not btns.is_down(2)
btns.button_down("alt")
btns.button_down("shift")
assert btns.is_any_down()
assert btns.is_down(0)
assert btns.is_down(1)
assert not btns.is_down(2)
btns.all_buttons_up()
assert not btns.is_any_down()
assert not btns.is_down(0)
assert not btns.is_down(1)
assert not btns.is_down(2)
