BasketBuilder::setBasketItemFields

public function setBasketItemFields(BitrixSaleBasketItem &$item, array $fields = array())
{
	$result = $item->setFields($fields);

	if(!$result->isSuccess())
	{
		foreach($result->getErrors() as $error)
		{
			$containerErrors = $this->getErrorsContainer()->getErrors();

			//avoid duplication
			if(is_array($containerErrors) && !empty($containerErrors))
			{
				foreach($this->getErrorsContainer()->getErrors() as $existError)
				{
					if($error->getMessage() !== $existError->getMessage())
					{
						$this->getErrorsContainer()->addError($error);
					}
				}
			}
			else
			{
				$this->getErrorsContainer()->addError($error);
			}
		}

		throw new BuildingException();
	}
}