Wikimedia Bugzilla is closed!

I am using ApiMain class in my own MediaWiki extension. 

I want to parse content of  some wiki pages from my site and I use ApiMain like following:

$innerRequest = new ApiMain(new FauxRequest(array(
  "action" => "parse",
  "pageid" => 223,
  "prop" => "wikitext",
  "format" => "php"
)));

$innerRequest->execute();
$data = $innerRequest->getResultData();

And if I activate my extension in any page like: {{#my_own_extension:}} caller page will change content (header, category) to parsed paged. Its behavior very strange. 

I've found following code in ApiParse.php (method getParsedSectionOrText):

323 $pout = $articleObj->getParserOutput();
324       if ( $getWikitext ) {
325         $rev = Revision::newFromTitle( $titleObj );
326         if ( $rev ) {
327           $this->text = $rev->getText();
328         }
329       }
330       return $pout;

See line 323: method getParserOutput() uses global $wgParser and it changes content of caller page. 

It seems to me that It should use clone of global parser (or instance) - not original. Content of caller page shouldn't change.