/**
* Tests sumOf with no parameters
*
* @return void
*/
public function testSumOfWithIdentity()
{
$collection = new Collection([1, 2, 3]);
$this->assertEquals(6, $collection->sumOf());
$collection = new Collection(['a' => 1, 'b' => 4, 'c' => 6]);
$this->assertEquals(11, $collection->sumOf());
}
