generation-aware playback statuses

internal/playback/session_controller_test.go

@@ -88,10 +88,11 @@ func TestNewSessionControllerStoresSyncPredicate(t *testing.T) {
 }
 
 type controllerEvent struct {
-	unit   Unit
-	action string
-	feed   FeedConfig
-	pair   SyncPairConfig
+	unit       Unit
+	action     string
+	generation uint64
+	feed       FeedConfig
+	pair       SyncPairConfig
 }
 
 type recordingVideoSlot struct{ events chan<- controllerEvent }
@@ -101,7 +102,10 @@ func (s recordingVideoSlot) Run(
 	initial FeedConfig,
 	commands <-chan FeedConfig,
 ) error {
-	s.events <- controllerEvent{unit: UnitVideo, action: "start", feed: initial}
+	s.events <- controllerEvent{
+		unit: UnitVideo, action: "start",
+		generation: generationFromContext(ctx), feed: initial,
+	}
 	for {
 		select {
 		case config := <-commands:
@@ -120,7 +124,10 @@ func (s recordingAudioSlot) Run(
 	initial FeedConfig,
 	commands <-chan FeedConfig,
 ) error {
-	s.events <- controllerEvent{unit: UnitAudio, action: "start", feed: initial}
+	s.events <- controllerEvent{
+		unit: UnitAudio, action: "start",
+		generation: generationFromContext(ctx), feed: initial,
+	}
 	for {
 		select {
 		case config := <-commands:
@@ -139,7 +146,10 @@ func (s recordingSyncSlot) Run(
 	initial SyncPairConfig,
 	commands <-chan SyncPairConfig,
 ) error {
-	s.events <- controllerEvent{unit: UnitSync, action: "start", pair: initial}
+	s.events <- controllerEvent{
+		unit: UnitSync, action: "start",
+		generation: generationFromContext(ctx), pair: initial,
+	}
 	for {
 		select {
 		case config := <-commands:
@@ -291,6 +301,9 @@ func TestSessionControllerStopsIndependentSlotsBeforeStartingSync(t *testing.T)
 			if !stopped[UnitVideo] || !stopped[UnitAudio] {
 				t.Fatalf("sync started before both independent slots stopped: %v", stopped)
 			}
+			if event.generation != 2 {
+				t.Fatalf("sync runtime generation = %d, want 2", event.generation)
+			}
 			break
 		}
 		if event.action != "stop" || (event.unit != UnitVideo && event.unit != UnitAudio) {