public function it_should_be_able_to_get_total_wrapping_paper_area_from_contained_boxes(BoxInterface $box1, BoxInterface $box2)
 {
     $box1Area = rand(1, 500);
     $box2Area = rand(1, 500);
     $box1->getWrappingPaperArea()->willReturn($box1Area);
     $box2->getWrappingPaperArea()->willReturn($box2Area);
     $this->addBox($box1);
     $this->addBox($box2);
     $this->getTotalWrappingPaperArea()->shouldBe($box1Area + $box2Area);
 }
 function it_can_get_total_wrapping_area(BoxInterface $box1, BoxInterface $box2)
 {
     $boxArea1 = 78;
     $boxArea2 = 15;
     $box1->getWrappingPaperArea()->willReturn($boxArea1);
     $box2->getWrappingPaperArea()->willReturn($boxArea2);
     $this->addBox($box1);
     $this->addBox($box2);
     $this->getTotalWrappingArea()->shouldBe($boxArea1 + $boxArea2);
 }