protected function processFileSpecification($artifact, $fileSpecification) {
        $this->files[] = fphp\File\StoredFile::fromSpecification($fileSpecification);
        $this->tracingLinks[] = new fphp\Artifact\TracingLink(
            "file", $artifact, $fileSpecification->getSourcePlace(), $fileSpecification->getTargetPlace());
        $this->logFile->log($artifact, "added file \"{$fileSpecification->getTarget()}\"");
    }