Uncaught Error: Call to a member function getPages() on null

A lot of PDFs (not all...) gives an Error (PHP 7, PHP 7.2 + 7.3)

Uncaught Error: Call to a member function getPages() on null

1. Download this test PDF: http://www.orimi.com/pdf-test.pdf
2. save to disk

3 run:

$parser = new \Smalot\PdfParser\Parser();  

try {        

    $pdf = $parser->parseFile($file);

} catch(Exception $e) {

}  
  // echo '<pre>';
  // print_r($pdf);
  // exit;
   
// Retrieve all pages from the pdf file.
**$pages  = $pdf->getPages();**   >>> ERROR
$pageNr = 1;

Reproduce the report with the linked pdf-test.pdf and the shown Parser::parseFile() followed by getPages() call. Start by tracing the returned value from parseFile() into getPages(); the issue does not identify a target behavior or acceptance criteria, so the expected handling must be clarified before implementation.