shouldPanic("SetCap", func() { vs.SetCap(10) })
	shouldPanic("SetLen", func() { vs.SetLen(-1) })
	shouldPanic("SetCap", func() { vs.SetCap(-1) })
	shouldPanic("SetCap", func() { vs.SetCap(6) }) // smaller than len
	vs.SetLen(5)
	if len(xs) != 5 || cap(xs) != 8 {
		t.Errorf("after SetLen(5), len, cap = %d, %d, want 5, 8", len(xs), cap(xs))
	}
	vs.SetCap(6)
	if len(xs) != 5 || cap(xs) != 6 {

	}
	s.Len = n
}

// SetCap sets v's capacity to n.
// It panics if v's Kind is not [Slice] or if n is smaller than the length or
// greater than the capacity of the slice.
func (v Value) SetCap(n int) {
	v.mustBeAssignable()
	v.mustBe(Slice)
	s := (*unsafeheader.Slice)(v.ptr)
	if n < s.Len || n > s.Cap {
		panic("reflect: slice capacity out of range in SetCap")
	}
	s.Cap = n
}