@Test
public void onAddToCartButtonClicked_addItemToCurrentOrder() {

    int itemQuantity = 32;
    ProductDto productToAdd = new ProductDto.Builder().build();
    given(currentProduct.get()).willReturn(productToAdd);
    presenter.onAddToCartButtonClicked(itemQuantity);
    ArgumentCaptor<ShoppingCartItem> captor = ArgumentCaptor.forClass(ShoppingCartItem.class);
    verify(currentOrder).addItem(captor.capture());
    ShoppingCartItem addedItem = captor.getValue();
    assertThat(addedItem.getProductDto()).isEqualTo(productToAdd);
    assertThat(addedItem.getQuantity()).isEqualTo(itemQuantity);
}