Thread::join PHP Méthode

    public function join()
    {
    }

 /**
  * @expectedException RuntimeException
  */
 public function testThreadAlreadyJoined()
 {
     $thread = new Thread();
     $this->assertEquals($thread->start(), true);
     $this->assertEquals($thread->join(), true);
     $this->assertEquals($thread->join(), false);
 }