transition_table = {
# Current state of the modifier, per `modifier_states`.
# |
# | Type of event that triggered this modifier update.
# | |
# | | Type of key that triggered this modiier update.
# | | |
# | | | Should we send a fake key press?
# | | | |
# | | | => | Accept the event?
# | | | | |
# | | | | | Next state.
# v v v v v v
('free', KEY_UP, 'modifier'): (False, True, 'free'),
('free', KEY_DOWN, 'modifier'): (False, False, 'pending'),
('pending', KEY_UP, 'modifier'): (True, True, 'free'),
('pending', KEY_DOWN, 'modifier'): (False, True, 'allowed'),
('suppressed', KEY_UP, 'modifier'): (False, False, 'free'),
('suppressed', KEY_DOWN, 'modifier'): (False, False, 'suppressed'),
('allowed', KEY_UP, 'modifier'): (False, True, 'free'),
('allowed', KEY_DOWN, 'modifier'): (False, True, 'allowed'),
('free', KEY_UP, 'hotkey'): (False, None, 'free'),
('free', KEY_DOWN, 'hotkey'): (False, None, 'free'),
('pending', KEY_UP, 'hotkey'): (False, None, 'suppressed'),
('pending', KEY_DOWN, 'hotkey'): (False, None, 'suppressed'),
('suppressed', KEY_UP, 'hotkey'): (False, None, 'suppressed'),
('suppressed', KEY_DOWN, 'hotkey'): (False, None, 'suppressed'),
('allowed', KEY_UP, 'hotkey'): (False, None, 'allowed'),
('allowed', KEY_DOWN, 'hotkey'): (False, None, 'allowed'),
('free', KEY_UP, 'other'): (False, True, 'free'),
('free', KEY_DOWN, 'other'): (False, True, 'free'),
('pending', KEY_UP, 'other'): (True, True, 'allowed'),
('pending', KEY_DOWN, 'other'): (True, True, 'allowed'),
# Necessary when hotkeys are removed after beign triggered, such as
# TestKeyboard.test_add_hotkey_multistep_suppress_modifier.
('suppressed', KEY_UP, 'other'): (False, False, 'allowed'),
('suppressed', KEY_DOWN, 'other'): (True, True, 'allowed'),
('allowed', KEY_UP, 'other'): (False, True, 'allowed'),
('allowed', KEY_DOWN, 'other'): (False, True, 'allowed'),
}