public void Transform_ThrowsArgumentException_IfThereIsNoFieldOrPropertyWithName()
{
// instance.RemoveNonExistentEvent(handler);
Expression instance = Expression.Parameter(typeof(Fixture), "instance");
Expression handler = Expression.Parameter(typeof(EventHandler), "handler");
Expression input = Expression.Call(instance, FixtureRemoveNonExistentEvent, handler);
// Validating that EventRemoveAttribute fails on non-existent event
EventRemoveAttribute attribute = new EventRemoveAttribute("NonExistentEvent");
Assert.ThrowsException <ArgumentException>(() => attribute.Transform(input));
}
public void Transform_ReplacesMethodCallExpressionWithAddAssignExpression_ForFieldEvents()
{
// Creating the expression "instance.RemoveEvent(handler)"
ParameterExpression instance = Expression.Parameter(typeof(Fixture), "instance");
ParameterExpression handler = Expression.Parameter(typeof(EventHandler), "handler");
Expression input = Expression.Call(instance, FixtureRemoveEvent, handler);
// Validating that EventRemoveAttribute creates expression unsubscribing to Event
Expression output = new EventRemoveAttribute("Event").Transform(input);
Action <Fixture, EventHandler> removeEvent = Expression.Lambda <Action <Fixture, EventHandler> >(output, new[] { instance, handler }).Compile();
bool eventEmitted = false;
Fixture fixture = new Fixture();
EventHandler eventHandler = (sender, e) => eventEmitted = true;
fixture.Event += eventHandler;
removeEvent(fixture, eventHandler);
fixture.TriggerEvent();
Assert.IsFalse(eventEmitted);
}
