Extend unit test to cover mixed-case hostnames and daisy-chained gossip;

reduce mock gossip timer to 2 seconds to trigger more often during tests.

nameserver/nameserver_test.go

@@ -83,6 +83,10 @@ func testNameservers(t *testing.T) {
 	lookupTimeout := 10 // ms
 	nameservers, grouter := makeNetwork(50)
 	defer stopNetwork(nameservers, grouter)
+	// This subset will sometimes lose touch with some of the others
+	badNameservers := nameservers[45:]
+	// This subset will remain well-connected, and we will deal mainly with them
+	nameservers = nameservers[:45]
 	nameserversByName := map[router.PeerName]*Nameserver{}
 	for _, n := range nameservers {
 		nameserversByName[n.ourName] = n
@@ -106,7 +110,13 @@ func testNameservers(t *testing.T) {
 	addMapping := func() {
 		nameserver := nameservers[rand.Intn(len(nameservers))]
 		addr := address.Address(rand.Int31())
-		hostname := fmt.Sprintf("hostname%d", rand.Int63())
+		// Create a hostname which has some upper and lowercase letters,
+		// and a unique number so we don't have to check if we allocated it already
+		randomBits := rand.Int63()
+		firstLetter := 'H' + (randomBits&1)*32
+		secondLetter := 'O' + (randomBits&2)*16
+		randomBits = randomBits >> 2
+		hostname := fmt.Sprintf("%c%cstname%d", firstLetter, secondLetter, randomBits)
 		mapping := mapping{hostname, []pair{{nameserver.ourName, addr}}}
 		mappings = append(mappings, mapping)
 
@@ -129,6 +139,12 @@ func testNameservers(t *testing.T) {
 		check(nameserver, mapping)
 	}
 
+	loseConnection := func() {
+		nameserver1 := badNameservers[rand.Intn(len(badNameservers))]
+		nameserver2 := nameservers[rand.Intn(len(nameservers))]
+		nameserver1.PeerGone(&router.Peer{Name: nameserver2.ourName})
+	}
+
 	deleteMapping := func() {
 		if len(mappings) <= 0 {
 			return
@@ -191,7 +207,10 @@ func testNameservers(t *testing.T) {
 		case 0.2 <= r && r < 0.3:
 			deleteMapping()
 
-		case 0.3 <= r && r < 0.9:
+		case 0.3 <= r && r < 0.35:
+			loseConnection()
+
+		case 0.35 <= r && r < 0.9:
 			doLookup()
 
 		case 0.9 <= r:

testing/gossip/mocks.go

@@ -97,7 +97,7 @@ type TestRouterClient struct {
 }
 
 func (grouter *TestRouter) run(sender router.PeerName, gossiper router.Gossiper, gossipChan chan interface{}) {
-	gossipTimer := time.Tick(10 * time.Second)
+	gossipTimer := time.Tick(2 * time.Second)
 	for {
 		select {
 		case gossip := <-gossipChan: