Function getProperError

packages/next/src/lib/is-error.ts:44–68

(err: unknown)

}

export function getProperError(err: unknown): Error {
  if (isError(err)) {
    return err
  }

  if (process.env.NODE_ENV === 'development') {
    // provide better error for case where `throw undefined`
    // is called in development
    if (typeof err === 'undefined') {
      return new Error(
        'An undefined error was thrown, ' +
          'see here for more info: https://nextjs.org/docs/messages/threw-undefined'
      )
    }

    if (err === null) {
      return new Error(
        'A null error was thrown, ' +
          'see here for more info: https://nextjs.org/docs/messages/threw-undefined'
      )
    }
  }

  return new Error(isPlainObject(err) ? safeStringifyLite(err) : err + '')
}