You're not showing any code so we can work with, but if current matchers doesn't work for you, you can create new ones:
function it_should_return_array_or_false()
{
$this->getOptions()->shouldBeArrayOrFalse();
}
public function getMatchers()
{
return [
'beArrayOrFalse' => function($subject, $value) {
return is_array($value) || $value === false;
},
];
}