public void Purchase_Test(RealTimeInventory inventory, uint toPurchase)
{
IInventoryServiceCompletedMessage response;
using (var testHelper = CreateInventoryServiceServer(inventory))
{
response = testHelper.PurchaseAsync(inventory, (int)toPurchase).WaitAndGetOperationResult();
}
InventoryServiceSpecificationHelper.AssertPurchase(inventory, toPurchase, response);
}