getGenericMockHelper example

namespace Symfony\Component\Console\Tests\Helper;

use PHPUnit\Framework\TestCase;
use Symfony\Component\Console\Exception\ExceptionInterface;
use Symfony\Component\Console\Helper\HelperInterface;
use Symfony\Component\Console\Helper\HelperSet;

class HelperSetTest extends TestCase
{
    public function testConstructor()
    {
        $mock_helper = $this->getGenericMockHelper('fake_helper');
        $helperset = new HelperSet(['fake_helper_alias' => $mock_helper]);

        $this->assertEquals($mock_helper, $helperset->get('fake_helper_alias'), '__construct sets given helper to helpers');
        $this->assertTrue($helperset->has('fake_helper_alias'), '__construct sets helper alias for given helper');
    }

    public function testSet()
    {
        $helperset = new HelperSet();
        $helperset->set($this->getGenericMockHelper('fake_helper', $helperset));
        $this->assertTrue($helperset->has('fake_helper'), '->set() adds helper to helpers');