code: protected function validateSupportedAlgorithm($algorithm)
      {
          if (!in_array($algorithm, $this->supported_algorithms, true)) {
              throw new InvalidArgumentException(
                  sprintf(
                      'Algorithm "%s" not supported',
                      $algorithm
                  )
              );
          }
  
          return $algorithm;
      }
docs: Validates that a given algorithm is supported.
  
  @param string $algorithm The {@link HasherAlgorithm} to validate.
  @return string The validated algorithm.
  @throws InvalidArgumentException If the algorithm isn't supported.