private function getOrCreateImportSpecification($data, $context = null)
{
if ($this->specificationOrCallback instanceof ImportSpecification) {
return $this->specificationOrCallback;
}
if (($specification = call_user_func($this->specificationOrCallback, $data, $context)) instanceof ImportSpecification) {
return $specification;
}
throw new InvalidCallbackResultException('Callback failed to create an instance of ImportSpecification.');
}