whisper: fix loop in expire() (#17532)

whisper/whisperv5/whisper.go

@@ -717,7 +717,7 @@ func (w *Whisper) expire() {
 				w.stats.messagesCleared++
 				w.stats.memoryCleared += sz
 				w.stats.memoryUsed -= sz
-				return true
+				return false
 			})
 			w.expirations[expiry].Clear()
 			delete(w.expirations, expiry)

whisper/whisperv5/whisper_test.go

@@ -487,8 +487,14 @@ func TestExpiry(t *testing.T) {
 	if err != nil {
 		t.Fatalf("failed generateMessageParams with seed %d: %s.", seed, err)
 	}
-
 	params.TTL = 1
+
+	messagesCount := 5
+
+	// Send a few messages one after another. Due to low PoW and expiration buckets
+	// with one second resolution, it covers a case when there are multiple items
+	// in a single expiration bucket.
+	for i := 0; i < messagesCount; i++ {
 		msg, err := NewSentMessage(params)
 		if err != nil {
 			t.Fatalf("failed to create new message with seed %d: %s.", seed, err)
@@ -502,12 +508,13 @@ func TestExpiry(t *testing.T) {
 		if err != nil {
 			t.Fatalf("failed to send envelope with seed %d: %s.", seed, err)
 		}
+	}
 
 	// wait till received or timeout
 	var received, expired bool
 	for j := 0; j < 20; j++ {
 		time.Sleep(100 * time.Millisecond)
-		if len(w.Envelopes()) > 0 {
+		if len(w.Envelopes()) == messagesCount {
 			received = true
 			break
 		}

whisper/whisperv6/whisper.go

@@ -900,7 +900,7 @@ func (whisper *Whisper) expire() {
 				whisper.stats.messagesCleared++
 				whisper.stats.memoryCleared += sz
 				whisper.stats.memoryUsed -= sz
-				return true
+				return false
 			})
 			whisper.expirations[expiry].Clear()
 			delete(whisper.expirations, expiry)

whisper/whisperv6/whisper_test.go

@@ -465,8 +465,14 @@ func TestExpiry(t *testing.T) {
 	if err != nil {
 		t.Fatalf("failed generateMessageParams with seed %d: %s.", seed, err)
 	}
-
 	params.TTL = 1
+
+	messagesCount := 5
+
+	// Send a few messages one after another. Due to low PoW and expiration buckets
+	// with one second resolution, it covers a case when there are multiple items
+	// in a single expiration bucket.
+	for i := 0; i < messagesCount; i++ {
 		msg, err := NewSentMessage(params)
 		if err != nil {
 			t.Fatalf("failed to create new message with seed %d: %s.", seed, err)
@@ -480,12 +486,13 @@ func TestExpiry(t *testing.T) {
 		if err != nil {
 			t.Fatalf("failed to send envelope with seed %d: %s.", seed, err)
 		}
+	}
 
 	// wait till received or timeout
 	var received, expired bool
 	for j := 0; j < 20; j++ {
 		time.Sleep(100 * time.Millisecond)
-		if len(w.Envelopes()) > 0 {
+		if len(w.Envelopes()) == messagesCount {
 			received = true
 			break
 		}