public function testGetId() { $period = new Day(Date::today()); $this->assertNotEquals(0, $period->getId()); $period = new Week(Date::today()); $this->assertNotEquals(0, $period->getId()); $period = new Month(Date::today()); $this->assertNotEquals(0, $period->getId()); $period = new Year(Date::today()); $this->assertNotEquals(0, $period->getId()); }