How to raise an event in a test that uses Moq? - unit-testing

Question

Here is part of code implementation in parent class:
handler.FooUpdateDelegate += FooUpdate(OnFooUpdate);
protected abstract void OnFooUpdate(ref IBoo boo, string s);
I have in test method mocked handler:
Mock<IHandler> mHandler = mockFactory.Create<IHandler>();
This...
mHandler.Raise(x => x.FooUpdateDelegate += null, boo, s);
...is not working. It says:
System.ArgumentException : Could not locate event for attach or detach method Void set_FooUpdateDelegate(FooUpdate).
I want to raise OnFooUpdate so it triggers the code to be tested in child class.
Question: How can I raise delegate (not common event handler) with Moq?
If I missed the point completely, please enligten me.

Answer 1

It looks like you are trying to raise a delegate rather than an event. Is this so?
Is your code along the lines of this?
public delegate void FooUpdateDelegate(ref int first, string second);
public class MyClass {
public FooUpdateDelegate FooUpdateDelegate { get; set; }
}
public class MyWrapperClass {
public MyWrapperClass(MyClass myclass) {
myclass.FooUpdateDelegate += HandleFooUpdate;
}
public string Output { get; private set; }
private void HandleFooUpdate(ref int i, string s) {
Output = s;
}
}
If so, then you can directly invoke the myClass FooUpdateDelegate like so
[TestMethod]
public void MockingNonStandardDelegate() {
var mockMyClass = new Mock<MyClass>();
var wrapper = new MyWrapperClass(mockMyClass.Object);
int z = 19;
mockMyClass.Object.FooUpdateDelegate(ref z, "ABC");
Assert.AreEqual("ABC", wrapper.Output);
}
EDIT: Adding version using interface
public interface IMyClass
{
FooUpdateDelegate FooUpdateDelegate { get; set; }
}
public class MyClass : IMyClass {
public FooUpdateDelegate FooUpdateDelegate { get; set; }
}
public class MyWrapperClass {
public MyWrapperClass(IMyClass myclass) {
myclass.FooUpdateDelegate += HandleFooUpdate;
}
public string Output { get; private set; }
private void HandleFooUpdate(ref int i, string s) {
Output = s;
}
}
[TestMethod]
public void MockingNonStandardDelegate()
{
var mockMyClass = new Mock<IMyClass>();
// Test fails with a Null Reference exception if we do not set up
// the delegate property.
// Can also use
// mockMyClass.SetupProperty(m => m.FooUpdateDelegate);
mockMyClass.SetupAllProperties();
var wrapper = new MyWrapperClass(mockMyClass.Object);
int z = 19;
mockMyClass.Object.FooUpdateDelegate(ref z, "ABC");
Assert.AreEqual("ABC", wrapper.Output);
}