prefer tickers to time.Sleep (Refs #790)

p2p/pex_reactor_test.go

@@ -1,6 +1,7 @@
 package p2p
 
 import (
+	"fmt"
 	"io/ioutil"
 	"math/rand"
 	"os"
@@ -98,15 +99,7 @@ func TestPEXReactorRunning(t *testing.T) {
 		require.Nil(err)
 	}
 
-	time.Sleep(1 * time.Second)
-
-	// check peers are connected after some time
-	for _, s := range switches {
-		outbound, inbound, _ := s.NumPeers()
-		if outbound+inbound == 0 {
-			t.Errorf("%v expected to be connected to at least one peer", s.NodeInfo().ListenAddr)
-		}
-	}
+	assertSomePeersWithTimeout(t, switches, 10*time.Millisecond, 10*time.Second)
 
 	// stop them
 	for _, s := range switches {
@@ -114,6 +107,31 @@ func TestPEXReactorRunning(t *testing.T) {
 	}
 }
 
+func assertSomePeersWithTimeout(t *testing.T, switches []*Switch, checkPeriod, timeout time.Duration) {
+	ticker := time.NewTicker(checkPeriod)
+	select {
+	case <-ticker.C:
+		// check peers are connected
+		allGood := true
+		for _, s := range switches {
+			outbound, inbound, _ := s.NumPeers()
+			if outbound+inbound == 0 {
+				allGood = false
+			}
+		}
+		if allGood {
+			return
+		}
+	case <-time.After(timeout):
+		numPeersStr := ""
+		for i, s := range switches {
+			outbound, inbound, _ := s.NumPeers()
+			numPeersStr += fmt.Sprintf("%d => {outbound: %d, inbound: %d}, ", i, outbound, inbound)
+		}
+		t.Errorf("expected all switches to be connected to at least one peer (switches: %s)", numPeersStr)
+	}
+}
+
 func TestPEXReactorReceive(t *testing.T) {
 	assert, require := assert.New(t), require.New(t)