I wonder why
> moment(undefined).isBefore()
true
but
> moment(null).isBefore()
false
Is there any rational explanation for this behavior?
moment(undefined) is equivalent to moment(), which assumes the initial state to be the current date/time.
moment(null), on the other hand, is not a thing. It is not valid (at least not in the version I'm playing with), and has undocumented results.
Of course, you can read the source code, and find that isBefore doesn't check for undefined either. In other words, momentjs is not expecting itself to be used this way, twice.
