let ``tick method`` () = true

Feature: Refunded or replaced items should be returned to stock

Scenario 1: Refunded items should be returned to stock
    Given a customer buys a black jumper
    And I have 3 black jumpers left in stock 
    When he returns the jumper for a refund 
    Then I should have 4 black jumpers in stock 

let mutable stockItem = { Count = 0 }

let [<Given>] ``a customer buys a black jumper`` () = ()
      
let [<Given>] ``I have (.*) black jumpers left in stock`` (n:int) =  
    stockItem <- { stockItem with Count = n }
      
let [<When>] ``he returns the jumper for a refund`` () =  
    stockItem <- { stockItem with Count = stockItem.Count + 1 }
      
let [<Then>] ``I should have (.*) black jumpers in stock`` (n:int) =     
    let passed = (stockItem.Count = n)
    Debug.Assert(passed)

public class StockStepDefinitions
{
   private StockItem _stockItem;

   [Given(@"a customer buys a black jumper")]
   public void GivenACustomerBuysABlackJumper()
   {
   }

   [Given(@"I have (.*) black jumpers left in stock")]
   public void GivenIHaveNBlackJumpersLeftInStock(int n)
   {
      _stockItem = new StockItem() { Count = n };  
   }

   [When(@"he returns the jumper for a refund")]
   public void WhenHeReturnsTheJumperForARefund()
   {
      _stockItem.Count += 1;
   }

   [Then(@"I should have (.*) black jumpers in stock")]
   public void ThenIShouldHaveNBlackJumpersInStock(int n)
   {
      Debug.Assert(_stockItem.Count == n);
   }
}