How to test add method in Kotlin object Singleton class

Question

I'm trying to do some testing in my object kotlin class, but I can getting an error in my thenReturn method when I try to pass the object. I get a Require: Unit! Found checkout. Someone can point me how is possible to test it??

If I remove thenReturn method I get this error:

Hints:
 1. missing thenReturn()
 2. you are trying to stub a final method, which is not supported
 3: you are stubbing the behaviour of another mock inside before 'thenReturn' instruction if completed

I refer this link but I can't get it.

object CheckoutRepository: CheckoutContract.Model {

    var checkout: MutableList<Checkout> = mutableListOf<Checkout>()

    override fun addProductToShoppingCart(checkoutProduct: Checkout){
        checkout.add(checkoutProduct)
    }

    override fun getProductsInShoppinCart() : List<Checkout>?{
        return checkout
    }

    override fun cleanCheckout(){
        checkout.clear()
    }
}



@Test
    fun test_with_mock() {
        val mock = mock<CheckoutContract.Model>()

        var checkout = Checkout("VOUCHER", "voucher", 35.0, 5)
        mock.addProductToShoppingCart(checkout)

        val answer = mock.getProductsInShoppinCart()
        `when`(mock.addProductToShoppingCart(checkout)).thenReturn(checkout)

        assertNotNull(checkout)
        assertEquals(checkout, answer)
    }

In your function addProductToShoppingCart don't have any return type — sasikumar, Sep 03 '19 at 12:41
Yes, I don't need the return type in function. Then, how can I test the addProductToShoppingCart method is working? — S.P., Sep 03 '19 at 12:50

sasikumar · Answer 1 · 2019-09-03T12:58:42.237

0

In your function addProductToShoppingCart don't have any return type.

if you want check Checkout class make the change in the functions then test case will pass

override fun addProductToShoppingCart(checkoutProduct: Checkout):Checkout{
    checkout.add(checkoutProduct)
return checkout
}

edited Sep 03 '19 at 12:58

answered Sep 03 '19 at 12:43

sasikumar

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Yes, I don't need the return type. If I remove the thenReturn I get the error: missing thenReturn() Check my question. That I want to do is test the addProductToShoppingCart is working – S.P. Sep 03 '19 at 12:54

How to test add method in Kotlin object Singleton class

1 Answers1