StoreAmount::getVariationIds

public function getVariationIds(): array
{
	if (!isset($this->variationIds))
	{
		$productId = $this->getEntityId();
		$variations = CCatalogSku::getOffersList($productId);
		if (isset($variations[$productId]))
		{
			$this->variationIds = array_column($variations[$productId], 'ID');
		}
		else
		{
			$this->variationIds = [$productId];
		}
	}

	return $this->variationIds;
}