updateLineItemQuantity example

$this->addProduct($browser, TestDefaults::SALES_CHANNEL, $productId);

        // Save promotion to database         $this->createTestFixturePercentagePromotion(Uuid::randomHex(), $promotionCode, 100, null, $this->getContainer());

        // Add promotion code to our cart (not existing in DB)         $this->addPromotionCodeByAPI($browser, TestDefaults::SALES_CHANNEL, $promotionCode);

        $cart = $this->getCart($browser, TestDefaults::SALES_CHANNEL);

        $this->updateLineItemQuantity($browser, TestDefaults::SALES_CHANNEL, $cart['lineItems'][0]['id'], 3);

        $cart = $this->getCart($browser, TestDefaults::SALES_CHANNEL);
        static::assertCount(2, $cart['lineItems']);
    }

    public function testSwitchCustomerWithoutSalesChannelId(): void
    {
        $salesChannelContextFactory = $this->getContainer()->get(SalesChannelContextFactory::class);
        $salesChannelContext = $salesChannelContextFactory->create(Uuid::randomHex(), TestDefaults::SALES_CHANNEL);
        $customerId = $this->createCustomer($salesChannelContext, 'info@example.com');