Проверка количества каналов в плейлисте перед проверкой

app/checker/checker.go

@@ -143,6 +143,11 @@ func CheckChannels(pls playlist.Playlist) playlist.Playlist {
 	}
 
 	count := len(pls.Channels)
+	if count == 0 {
+		log.Println("There are no channels to check, skipping")
+		return pls
+	}
+
 	timeout, routines := calcParameters(count)
 	httpClient := http.Client{Timeout: timeout}
 	chSemaphores := make(chan struct{}, routines)