Duration for overnight events

[markoj3s]

I don't know if it is for a specific purpose or simply a bug, but just in case of let me share what I am curious about:

Inside the Occurence class, duration method is defined as follows:

def duration
      end_time - start_time
end

 However, in the case of an overnight event, this would return a negative value.

Since it is a common case, I was thinking that this was maybe for a specific purpose I am not aware of ?

[andremiotto]

start_time and end_time must be 'datetime' format on the database