I have a C# method with an out parameter:
public bool TryGetNext(out Bestellung? bestellung);
When setting up a mock for this method using Moq, how do I:
Correctly handle the out parameter in the Setup?
Make the mock return different values and assign different values to the out parameter on subsequent calls?
Cause i already needed this information twice and hat troubles researching it every time, i post this here.
Lets pretend we have this methode,
public bool TryGetNext(out Bestellung? bestellung);
what makes it special, it does have a Out Parameter usually if you dont care
It.isAny<Bestellung>()
would be right do declare that this setup is acting on any input as long it is of Type Bestellung
In Case of a Out you need to use It.Ref<Bestellung>.IsAny.
How are we get the setup to give us different results every time we call it?
In my case is the Original Methode a DeQueue so i rebuild this.
.Returns((out Bestellung? bestellung) => {}
here we get the variable bestellung we just assign and with the return as usually assign the return value of the method itself.
Queue<Bestellung> bestellungenQueue = new Queue<Bestellung>(
[
new BestellungBuilder().WithAuftragsNr(123456).Build(),
new BestellungBuilder().WithAuftragsNr(789456).Build()
]);
Mock<IBestellungRepository> mockRepository = new Mock<IBestellungRepository>();
mockRepository.Setup(m => m.TryGetNext(out It.Ref<Bestellung>.IsAny!))
.Returns((out Bestellung? bestellung) =>
{
if (bestellungenQueue.Count > 0)
{
bestellung = bestellungenQueue.Dequeue();
return bestellung != null; // Return true if not null
}
bestellung = null;
return false; // No more items
});
