Moq: How to get to a parameter passed to a method of a mocked service
Imagine this class
public class Foo {
private Handler _h;
public Foo(Handler h)
{
_h = h;
}
public void Bar(int i)
{
_h.AsyncHandle(CalcOn(i));
}
private SomeResponse CalcOn(int i)
{
...;
}
}
Mo(q)cking Handler in a test of Foo, how would I be able to check what Bar()
has passed to _h.AsyncHandle
?
You can use the Mock.Callback-method:
var mock = new Mock<Handler>();
SomeResponse result = null;
mock.Setup(h => h.AsyncHandle(It.IsAny<SomeResponse>()))
.Callback<SomeResponse>(r => result = r);
// do your test
new Foo(mock.Object).Bar(22);
Assert.NotNull(result);
If you only want to check something simple on the passed in argument, you also can do it directly:
mock.Setup(h => h.AsyncHandle(It.Is<SomeResponse>(response => response != null)));
An alternative is to use Capture.In
, which is an out-of-the-box feature in Moq that lets you capture arguments into a collection:
//Arrange
var args = new List<SomeResponse>();
mock.Setup(h => h.AsyncHandle(Capture.In(args)));
//Act
new Foo(mock.Object).Bar(22);
//Assert
//... assert args.Single() or args.First()