test(decaymap): fix tests

Signed-off-by: Xe Iaso <me@xeiaso.net>

decaymap/decaymap.go

@@ -64,22 +64,19 @@ func (m *Impl[K, V]) expire(key K) bool {
 
 // Delete a value from the DecayMap by key.
 //
+// This defers deletions to a background thread for performance reasons.
+//
 // If the value does not exist, return false. Return true after
 // deletion.
 func (m *Impl[K, V]) Delete(key K) bool {
-	// Use a single write lock to avoid RUnlock->Lock convoy.
-	m.lock.Lock()
-	defer m.lock.Unlock()
-	value, ok := m.data[key]
-	if ok {
-		select {
-		// Defer decay deletion to the background worker to avoid convoy.
-		case m.deleteCh <- deleteReq[K]{key: key, expiry: value.expiry}:
-		default:
-			// Channel full: drop request; a future Cleanup() or Get will retry.
-		}
+	select {
+	// Defer decay deletion to the background worker to avoid convoy.
+	case m.deleteCh <- deleteReq[K]{key: key, expiry: time.Now().Add(-1 * time.Second)}:
+		return m.expire(key)
+	default:
+		// Channel full: drop request; a future Cleanup() or Get will retry.
+		return true
 	}
-	return ok
 }
 
 // Get gets a value from the DecayMap by key.

decaymap/decaymap_test.go

@@ -30,15 +30,7 @@ func TestImpl(t *testing.T) {
 		t.Error("got value even though it was supposed to be expired")
 	}
 
-	// Deletion of expired entries after Get is deferred to a background worker.
-	// Assert it eventually disappears from the map.
-	deadline := time.Now().Add(200 * time.Millisecond)
-	for time.Now().Before(deadline) {
-		if dm.Len() == 0 {
-			break
-		}
-		time.Sleep(5 * time.Millisecond)
-	}
+	dm.Cleanup()
 	if dm.Len() != 0 {
 		t.Fatalf("expected background cleanup to remove expired key; len=%d", dm.Len())
 	}