/**
  * @test
  */
 public function isGeneratingSomeString()
 {
     $string = AstronautaDeMarmore::randomize();
     $this->assertNotNull($string);
     $this->assertInternalType('string', $string);
     $this->assertNotEquals(0, strlen($string));
 }
<?php

//require 'vendor/autoload.php'; altere para o seu caminho completo
use Andrebian\Astronauta\AstronautaDeMarmore;
echo AstronautaDeMarmore::randomize();