interface Promise<T> {
  /**
   * Attaches callbacks for the resolution and/or rejection of the Promise.
   * @param onfulfilled The callback to execute when the Promise is resolved.
   * @param onrejected The callback to execute when the Promise is rejected.
   * @returns A Promise for the completion of which ever callback is executed.
   */
  then<TResult1 = T, TResult2 = never>(
    onfulfilled?:
      | ((value: T) => TResult1 | PromiseLike<TResult1>)
      | undefined
      | null,
    onrejected?:
      | ((reason: unknown) => TResult2 | PromiseLike<TResult2>)
      | undefined
      | null,
  ): Promise<TResult1 | TResult2>;

  /**
   * Attaches a callback for only the rejection of the Promise.
   * @param onrejected The callback to execute when the Promise is rejected.
   * @returns A Promise for the completion of the callback.
   */
  catch<TResult = never>(
    onrejected?:
      | ((reason: unknown) => TResult | PromiseLike<TResult>)
      | undefined
      | null,
  ): Promise<T | TResult>;
}