function it_reverses_the_automata(State $state, Transition $transition, Symbol $symbol)
{
$state->isFinal()->willReturn(true);
$state->getTransitions()->willReturn($transition);
$transition->getSymbol()->willReturn($symbol);
$transition->getState()->willReturn($state);
$this->reverse()->shouldBeAnInstanceOf(NFA::class);
}
/**
* @return NFA
*/
public function reverse()
{
$nfa = new NFA();
$map = [spl_object_hash($this->state) => ['original' => $this->state, 'reversed' => new NFAState(true), 'starting' => $this->state->isFinal()]];
for ($i = 0; $i < count($map); $i++) {
$key = array_keys($map)[$i];
if ($map[$key]['starting']) {
$nfa->addStartingState($map[$key]['reversed']);
}
foreach ($map[$key]['original']->getTransitions() as $transition) {
$state = $transition->getState();
$hash = spl_object_hash($state);
if (!array_key_exists($hash, $map)) {
$map[$hash] = ['original' => $state, 'reversed' => new NFAState(false), 'starting' => $state->isFinal()];
}
$map[$hash]['reversed']->on($transition->getSymbol())->visit($map[$key]['reversed']);
}
}
return $nfa;
}