Browsing a file in Diffusion (eg https://my.phorge.site/source/myrepo/browse/master/myfile) fails under PHP 8.1 with strlen(null) error.
Stack trace:
AH01071: Got error 'PHP message: [2023-07-04 16:15:20] EXCEPTION: (RuntimeException) strlen(): Passing null to parameter #1 ($string) of type string is deprecated at [<arcanist>/src/error/PhutilErrorHandler.php:261]PHP message: arcanist(head=master, ref.master=8130241a11ac, custom=4), phorge(head=master, ref.master=7c1487e4dcfa)PHP message: #0 <#2> PhutilErrorHandler::handleError(integer, string, string, integer) called at [<phorge>/src/applications/diffusion/document/DiffusionDocumentRenderingEngine.php:90]PHP message: #1 <#2> DiffusionDocumentRenderingEngine::willRenderRef(PhabricatorDocumentRef) called at [<phorge>/src/applications/files/document/render/PhabricatorDocumentRenderingEngine.php:116]PHP message: #2 <#2> PhabricatorDocumentRenderingEngine::newDocumentView(PhabricatorDocumentRef) called at [<phorge>/src/applications/diffusion/controller/DiffusionBrowseController.php:193]PHP message: #3 <#2> DiffusionBrowseController::browseFile() called at [<phorge>/src/applications/diffusion/controller/DiffusionBrowseController.php:46]PHP message: #4 <#2> DiffusionBrowseController::handleRequest(AphrontRequest) called at [<phorge>/src/aphront/configuration/AphrontApplicationConfiguration.php:284]PHP message: #5 phlog(RuntimeException) called at [<phorge>/src/aphront/handler/PhabricatorDefaultRequestExceptionHandler.php:41]PHP message: #6 PhabricatorDefaultRequestExceptionHandler::handleRequestThrowable(AphrontRequest, RuntimeException) called at [<phorge>/src/aphront/configuration/AphrontApplicationConfiguration.php:751]PHP message: #7 AphrontApplicationConfiguration::handleThrowable(RuntimeException) called at [<phorge>/src/aphront/configuration/AphrontApplicationConfiguration.php:296]PHP message: #8 AphrontApplicationConfiguration::processRequest(AphrontRequest, PhutilDeferredLog, AphrontPHPHTTPSink, MultimeterControl) called at [<phorge>/src/aphront/configuration/AphrontApplicationConfiguration.php:204]PHP message: #9 AphrontApplicationConfiguration::runHTTPRequest(AphrontPHPHTTPSink) called at [<phorge>/webroot/index.php:35]'