cluster: Make peersFromMultiaddrs remove any duplicates.

Use it to find out the number of peers in the config and prevent
peerAdd test failures.

License: MIT
Signed-off-by: Hector Sanjuan <code@hector.link>

peer_manager_test.go

@@ -91,7 +91,7 @@ func TestClustersPeerAdd(t *testing.T) {
 		// check that they are part of the configuration
 		// This only works because each peer only has one multiaddress
 		// (localhost)
-		if len(c.config.Peers) != nClusters-1 {
+		if len(peersFromMultiaddrs(c.config.Peers)) != nClusters-1 {
 			t.Error(c.config.Peers)
 			t.Errorf("%s: expected different cluster peers in the configuration", c.id)
 		}

util.go

@@ -81,14 +81,22 @@ func multiaddrJoin(addr ma.Multiaddr, p peer.ID) ma.Multiaddr {
 	return addr.Encapsulate(pidAddr)
 }
 
+// returns all the different peers in the given addresses.
+// each peer only will appear once in the result, even if several
+// multiaddresses for it are provided.
 func peersFromMultiaddrs(addrs []ma.Multiaddr) []peer.ID {
 	var pids []peer.ID
+	pm := make(map[peer.ID]struct{})
 	for _, addr := range addrs {
 		pid, _, err := multiaddrSplit(addr)
 		if err != nil {
 			continue
 		}
-		pids = append(pids, pid)
+		_, ok := pm[pid]
+		if !ok {
+			pm[pid] = struct{}{}
+			pids = append(pids, pid)
+		}
 	}
 	return pids
 }