Method _adjustIndex

packages/forms/src/model/form_array.ts:510–512

* Adjusts a negative index by summing it with the length of the array. For very negative * indices, the result may remain negative. * @internal

(index: number)

   * @internal
   */
  private _adjustIndex(index: number): number {
    return index < 0 ? index + this.length : index;
  }

  /** @internal */
  override _syncPendingControls(): boolean {