If this was new construction and an inspector saw this, he's make you pull new wire. Since it's existing, splice some extra wire onto the short piece so you have room to work with the switch. Never, ever cut wire in a junction box. you never know when you might need it.

If this was new construction and an inspector saw this, he's make you pull new wire. Since it's existing, wire nut some extra wire onto the short piece so you have room to work with the switch. Never, ever cut wire in a junction box. you never know when you might need it.