Fix Thunderbird deselection and review test synchronization

internal/review/worker_test.go

@@ -197,30 +197,47 @@ func TestWorkerUsesNewestFocusAfterConcurrentCapture(t *testing.T) {
 }
 
 func TestWorkerRecapturesAndRepairsStaleCursor(t *testing.T) {
-	capturer := &fakeCapturer{calls: make(chan captureCall, 2)}
-	worker, cancel := startWorker(t, capturer, time.Second)
-	defer cancel()
-
+	capturer := &fakeCapturer{calls: make(chan captureCall, 1)}
+	worker, err := NewWorker(capturer, time.Second)
+	if err != nil {
+		t.Fatal(err)
+	}
 	firstTree := threeNodeTree(t)
-	worker.SyncFocus(objectID("/first"))
-	if err := worker.Move(NextSibling); err != nil {
+	cursor, err := NewCursor(firstTree)
+	if err != nil {
 		t.Fatal(err)
 	}
-	firstCall := <-capturer.calls
-	firstCall.result <- captureResult{tree: firstTree}
-	if result := waitResult(t, worker); result.Err != nil || result.Position.Current.Name != "Second" {
-		t.Fatalf("initial result = %#v", result)
+	focus := objectID("/first")
+	worker.SyncFocus(focus)
+	if _, err := cursor.SyncFocus(focus); err != nil {
+		t.Fatal(err)
 	}
+	if position, moved, err := cursor.Move(NextSibling); err != nil || !moved || position.Current.Name != "Second" {
+		t.Fatalf("initial move = %#v, %v, %v", position, moved, err)
+	}
+	// Establish stale state before starting the move. A pending wakeFocus in
+	// a running worker can otherwise repair this cursor during invalidation,
+	// so the queued move legitimately needs no capture and the test hangs.
 	firstTree.Invalidate(objectID("/second"))
-
-	if err := worker.Move(NextSibling); err != nil {
-		t.Fatal(err)
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+	results := make(chan moveResult, 1)
+	go func() { results <- worker.move(ctx, cursor, NextSibling) }()
+	select {
+	case call := <-capturer.calls:
+		call.result <- captureResult{tree: threeNodeTree(t)}
+	case result := <-results:
+		t.Fatalf("stale cursor did not recapture: %#v", result)
+	case <-time.After(time.Second):
+		t.Fatal("timed out waiting for stale cursor capture")
 	}
-	secondCall := <-capturer.calls
-	secondCall.result <- captureResult{tree: threeNodeTree(t)}
-	result := waitResult(t, worker)
-	if result.Err != nil || !result.Moved || result.Position.Current.Name != "Second" {
-		t.Fatalf("recovered result = %#v, want Second", result)
+	select {
+	case result := <-results:
+		if result.Err != nil || !result.Moved || result.Position.Current.Name != "Second" {
+			t.Fatalf("recovered result = %#v, want Second", result)
+		}
+	case <-time.After(time.Second):
+		t.Fatal("timed out waiting for recovered move")
 	}
 }