code: function normalizeInput(input) {
      var ret;
      if (input instanceof Uint8Array) {
          ret = input;
      }
      else if (input instanceof Buffer) {
          ret = new Uint8Array(input);
      }
      else if (typeof (input) === 'string') {
          ret = new Uint8Array(Buffer.from(input, 'utf8'));
      }
      else {
          throw new Error(ERROR_MSG_INPUT);
      }
      return ret;
  }
docs: For convenience, let people hash a string, not just a Uint8Array