TransitionEvent example

foreach ($places as $place) {
            $marking->unmark($place);
        }
    }

    private function transition(object $subject, Transition $transition, Marking $marking, array $context): array
    {
        if (!$this->shouldDispatchEvent(WorkflowEvents::TRANSITION, $context)) {
            return $context;
        }

        $event = new TransitionEvent($subject, $marking, $transition, $this, $context);

        $this->dispatcher->dispatch($event, WorkflowEvents::TRANSITION);
        $this->dispatcher->dispatch($event, sprintf('workflow.%s.transition', $this->name));
        $this->dispatcher->dispatch($event, sprintf('workflow.%s.transition.%s', $this->name, $transition->getName()));

        return $event->getContext();
    }

    private function enter(object $subject, Transition $transition, Marking $marking, array $context): void
    {
        $places = $transition->getTos();