public function convert($input)
 {
     if (!$input) {
         return;
     }
     if (is_numeric($input) && $input < 100000) {
         //Date may be 42338 (=> 30.11.2015
         $date = \PHPExcel_Shared_Date::ExcelToPHPObject($input);
         return $this->formatOutput($date);
     }
     return parent::convert($input);
 }
 /**
  * @dataProvider getConvertData
  */
 public function testConvert($inputData, $expectedResult)
 {
     $this->assertEquals($expectedResult, $this->sut->convert($inputData));
 }