Sylius\Behat\Page\Shop\Cart\SummaryPageInterface::getGrandTotal PHP Method

    public function getGrandTotal();

 /**
  * @Then the grand total value should be :total
  * @Then my cart total should be :total
  */
 public function myCartTotalShouldBe($total)
 {
     $this->summaryPage->open();
     Assert::same($this->summaryPage->getGrandTotal(), $total, 'Grand total should be %2$s, but it is %s.');
 }