function it_can_tell_the_previous_period_even_if_it_is_in_the_previous_year()
{
$this->beConstructedWith(Month::fromName('January'), Year::fromNumber(2014));
$next = $this->previous();
$next->getMonth()->shouldBeLike(Month::fromNumber(12));
$next->getYear()->shouldBeLike(Year::fromNumber(2013));
}
public function previous()
{
if (1 === $this->month->toNumber()) {
$month = Month::fromNumber(12);
$year = $this->year->previous();
} else {
$month = $this->month->previous();
$year = $this->year;
}
return new self($month, $year);
}
function it_can_not_be_constructed_with_incorrect_date()
{
$this->shouldThrow('InvalidArgumentException')->during('__construct', [32, new Period(Month::fromNumber(4), Year::fromNumber(2013))]);
}
