# validated: 2024-01-19 DS aaea85ff1656 ParallelRaceGroup.java
from __future__ import annotations
from typing import Set
from .command import Command, InterruptionBehavior
from .commandscheduler import CommandScheduler
from .exceptions import IllegalCommandUse
from .util import flatten_args_commands
[docs]
class ParallelRaceGroup(Command):
"""
A composition that runs a set of commands in parallel, ending when any one of the commands ends
and interrupting all the others.
The rules for command compositions apply: command instances that are passed to it cannot be
added to any other composition or scheduled individually, and the composition requires all
subsystems its components require.
"""
def __init__(self, *commands: Command):
"""
Creates a new ParallelCommandRace. The given commands will be executed simultaneously, and will
"race to the finish" - the first command to finish ends the entire command, with all other
commands being interrupted.
:param commands: the commands to include in this composition.
"""
super().__init__()
self._commands: Set[Command] = set()
self._runs_when_disabled = True
self._finished = True
self._interrupt_behavior = InterruptionBehavior.CANCEL_INCOMING
self.add_commands(*commands)
[docs]
def add_commands(self, *commands: Command):
"""
Adds the given commands to the group.
:param commands: Commands to add to the group.
"""
commands = flatten_args_commands(commands)
if not self._finished:
raise IllegalCommandUse(
"Commands cannot be added to a composition while it is running"
)
CommandScheduler.get_instance().register_composed_commands(commands)
for command in commands:
in_common = command.get_requirements().intersection(self.requirements)
if in_common:
raise IllegalCommandUse(
"Multiple commands in a parallel composition cannot require the same subsystems.",
common=in_common,
)
self._commands.add(command)
self.requirements.update(command.get_requirements())
self._runs_when_disabled = (
self._runs_when_disabled and command.runs_when_disabled()
)
if command.get_interruption_behavior() == InterruptionBehavior.CANCEL_SELF:
self._interrupt_behavior = InterruptionBehavior.CANCEL_SELF
[docs]
def initialize(self):
self._finished = False
for command in self._commands:
command.initialize()
[docs]
def execute(self):
for command in self._commands:
command.execute()
if command.is_finished():
self._finished = True
[docs]
def end(self, interrupted: bool):
for command in self._commands:
command.end(not command.is_finished())
[docs]
def is_finished(self) -> bool:
return self._finished
[docs]
def runs_when_disabled(self) -> bool:
return self._runs_when_disabled
[docs]
def get_interruption_behavior(self) -> InterruptionBehavior:
return self._interrupt_behavior