code: protected function hasItemHrefIndexFile(QtiRunnerServiceContext $context, $itemIdentifier)
      {
          // In case the context is adaptive, it means that the delivery was compiled in a version
          // we are 100% sure it produced Item Href Index Files.
          if ($context->isAdaptive()) {
              return true;
          } else {
              $indexFile = $this->getItemHrefIndexFile($context, $itemIdentifier);
              return $indexFile->exists();
          }
      }
docs: Checks if the AssessmentItemRef Identifier is in the index.
  
  @param QtiRunnerServiceContext $context
  @param string $itemIdentifier
  @return boolean