/** @test **/
public function it_allows_adding_one_weight_to_another()
{
$weight_1 = new Weight(500, 'g');
$weight_2 = new Weight(2, 'kg');
$weight_1->add($weight_2);
$this->assertEquals(2500, $weight_1->value());
}
/**
* Get the total weight for a package of items.
*
* @param Unit|string $unit The unit the weight should be in
*
* @return Weight
*/
public function weight($unit = 'kg')
{
$total_weight = new Weight(0, $unit);
foreach ($this->items as $item) {
$total_weight->add($item->weight());
}
return $total_weight;
}
