I get this Error when trying to run a PhpUnit test on my Drupal project

TypeError: Argument 1 passed to Drupal\views\Plugin\views\HandlerBase::__construct() must be of the type array phpunit

My code is:

use Drupal\views_simple_math_field\Plugin\views\field\SimpleMathField;

class BasicTest extends PHPUnit_Framework_TestCase
{
   public function test_proba()
   {
     $first = 25;
     $second = 5;
     $result = 13;
     $test = new SimpleMathField();
     $working = $test->plus($first,$second,$result);
     $this->assertEquals($result,$working);

 }
}

I think the error is within " $test = new SimpleMathField();". The test works when I exclude SimpleMathField