public function testSearchReturnsFalseWhenItemIsNotFound()
 {
     $c = new Collection([1, 2, 3, 4, 5, 'foo' => 'bar']);
     $this->assertFalse($c->search(6));
     $this->assertFalse($c->search('foo'));
     $this->assertFalse($c->search(function ($value) {
         return $value < 1 && is_numeric($value);
     }));
     $this->assertFalse($c->search(function ($value) {
         return $value == 'nope';
     }));
 }