Swift Quiver takes a bonus action to cast, then it lets you use a bonus action to make two attacks. So the turn you cast it, you use your bonus action just to cast it, then you need another bonus action to use it's ability to make two attacks, right?
The description of the Swift Quiver spell says (PHB, p. 279):
You transmute your quiver so it produces an endless supply of nonmagical ammunition, which seems to leap into your hand when you reach for it.
On each of your turns until the spell ends, you can use a bonus action to make two attacks with a weapon that uses ammunition from the quiver. Each time you make such a ranged attack, your quiver magically replaces the piece of ammunition you used with a similar piece of nonmagical ammunition. [...]
Does Swift Quiver let you make 2 extra attacks with a bonus action on the same turn you cast it?