Observationally, how can we tell the difference between a white$-$dwarf supernova and a massive$-$star supernova?

A massive$-$star supernova is brighter than a white$-$dwarf supernova.

We cannot yet tell the difference between a massive$-$star supernova and a white$-$dwarf supernova

A massive$-$star supernova happens only once, while a white$-$dwarf supernova can repeat periodically.

The light of a white$-$dwarf supernova fades steadily, while the light of a massive$-$star supernova brightens for many weeks.

The white dwarf supernova fades quickly at first and then more gradually a few weeks after the peak, while the massive star supernova fades in a more complicated pattern.