public function testReadNextWhenIsNotDone()
 {
     if (defined('HHVM_VERSION')) {
         $this->markTestSkipped('HHVM Fail to invoke readNext( WTF !!).');
     }
     $message = new RpbListKeysResp();
     $this->iterator->expects($this->once())->method('current')->willReturn($message);
     $this->instance->expects($this->once())->method('extract')->willReturn('value')->with($this->equalTo($message));
     $this->assertEquals('value', $this->invokeMethod($this->instance, 'readNext'));
 }