PeerStore Ring Move? Possible Bug?

[qwtsc]

When I looked at the code of peerContactsSet, this function seems to be wrong.

func (p *peerContactsSet) next() []string {
	count := kNodes
	if count > len(p.set) {
		count = len(p.set)
	}
	x := make([]string, 0, count)
	xx := make(map[string]bool) //maps are easier to dedupe
	for range p.set {
		nid := p.ring.Move(1).Value.(string)  <----this line will always return the first next item since p.ring never change its pos.
		if _, ok := xx[nid]; p.set[nid] && !ok {
			xx[nid] = true
		}
		if len(xx) >= count {
			break
		}
	}
...

The move function will return a new pointer rather than change the original pointer as demonstrated in this playground.

func (r *Ring) Move(n int) *Ring {
	if r.next == nil {
		return r.init()
	}
	switch {
	case n < 0:
		for ; n < 0; n++ {
			r = r.prev
		}
	case n > 0:
		for ; n > 0; n-- {
			r = r.next
		}
	}
	return r
}

Need a PR to fix it?

[nictuku]

It's been a while since I've written this, but if you could write a unit test demonstrating the fix, a PR would be great, yes.