example.cs

// Option 1
var subject = new EventRaisingClass();
using (var scope = subject.Monitor())
{
    subject.ShouldRaise("NonExistingEvent");
}
  
// Option 2
var subject = new EventRaisingClass();
using (Monitor<EventRaisingClass> monitoredSubject = subject.Monitor()
{
    monitoredSubject.Should().Raise("NonExistingEvent");
}

// Alternative names for Monitor extension method: TrackEvents, MonitorForEvents
 

Option 2