Show a notification if checking for updates via button and there are none available

osu.Desktop/Updater/SquirrelUpdateManager.cs

@@ -37,9 +37,9 @@ namespace osu.Desktop.Updater
             Splat.Locator.CurrentMutable.Register(() => new SquirrelLogger(), typeof(Splat.ILogger));
         }
 
-        protected override async Task PerformUpdateCheck() => await checkForUpdateAsync();
+        protected override async Task<bool> PerformUpdateCheck() => await checkForUpdateAsync();
 
-        private async Task checkForUpdateAsync(bool useDeltaPatching = true, UpdateProgressNotification notification = null)
+        private async Task<bool> checkForUpdateAsync(bool useDeltaPatching = true, UpdateProgressNotification notification = null)
         {
             // should we schedule a retry on completion of this check?
             bool scheduleRecheck = true;
@@ -51,7 +51,7 @@ namespace osu.Desktop.Updater
                 var info = await updateManager.CheckForUpdate(!useDeltaPatching);
                 if (info.ReleasesToApply.Count == 0)
                     // no updates available. bail and retry later.
-                    return;
+                    return false;
 
                 if (notification == null)
                 {
@@ -103,6 +103,8 @@ namespace osu.Desktop.Updater
                     Scheduler.AddDelayed(async () => await checkForUpdateAsync(), 60000 * 30);
                 }
             }
+
+            return true;
         }
 
         protected override void Dispose(bool isDisposing)

osu.Game/Overlays/Settings/Sections/General/UpdateSettings.cs

@@ -4,9 +4,11 @@
 using System.Threading.Tasks;
 using osu.Framework;
 using osu.Framework.Allocation;
+using osu.Framework.Graphics.Sprites;
 using osu.Framework.Platform;
 using osu.Framework.Screens;
 using osu.Game.Configuration;
+using osu.Game.Overlays.Notifications;
 using osu.Game.Overlays.Settings.Sections.Maintenance;
 using osu.Game.Updater;
 
@@ -21,6 +23,9 @@ namespace osu.Game.Overlays.Settings.Sections.General
 
         private SettingsButton checkForUpdatesButton;
 
+        [Resolved]
+        private NotificationOverlay notifications { get; set; }
+
         [BackgroundDependencyLoader(true)]
         private void load(Storage storage, OsuConfigManager config, OsuGame game)
         {
@@ -30,7 +35,7 @@ namespace osu.Game.Overlays.Settings.Sections.General
                 Bindable = config.GetBindable<ReleaseStream>(OsuSetting.ReleaseStream),
             });
 
-            if (updateManager?.CanCheckForUpdate == true)
+            //if (updateManager?.CanCheckForUpdate == true)
             {
                 Add(checkForUpdatesButton = new SettingsButton
                 {
@@ -38,7 +43,19 @@ namespace osu.Game.Overlays.Settings.Sections.General
                     Action = () =>
                     {
                         checkForUpdatesButton.Enabled.Value = false;
-                        Task.Run(updateManager.CheckForUpdateAsync).ContinueWith(t => Schedule(() => checkForUpdatesButton.Enabled.Value = true));
+                        Task.Run(updateManager.CheckForUpdateAsync).ContinueWith(t => Schedule(() =>
+                        {
+                            if (!t.Result)
+                            {
+                                notifications.Post(new SimpleNotification
+                                {
+                                    Text = $"You are running the latest release ({game.Version})",
+                                    Icon = FontAwesome.Solid.CheckCircle,
+                                });
+                            }
+
+                            checkForUpdatesButton.Enabled.Value = true;
+                        }));
                     }
                 });
             }

osu.Game/Updater/SimpleUpdateManager.cs

@@ -30,7 +30,7 @@ namespace osu.Game.Updater
             version = game.Version;
         }
 
-        protected override async Task PerformUpdateCheck()
+        protected override async Task<bool> PerformUpdateCheck()
         {
             try
             {
@@ -53,12 +53,17 @@ namespace osu.Game.Updater
                             return true;
                         }
                     });
+
+                    return true;
                 }
             }
             catch
             {
                 // we shouldn't crash on a web failure. or any failure for the matter.
+                return true;
             }
+
+            return false;
         }
 
         private string getBestUrl(GitHubRelease release)

osu.Game/Updater/UpdateManager.cs

@@ -57,25 +57,28 @@ namespace osu.Game.Updater
 
         private readonly object updateTaskLock = new object();
 
-        private Task updateCheckTask;
+        private Task<bool> updateCheckTask;
 
-        public async Task CheckForUpdateAsync()
+        public async Task<bool> CheckForUpdateAsync()
         {
-            if (!CanCheckForUpdate)
-                return;
-
-            Task waitTask;
+            Task<bool> waitTask;
 
             lock (updateTaskLock)
                 waitTask = (updateCheckTask ??= PerformUpdateCheck());
 
-            await waitTask;
+            bool hasUpdates = await waitTask;
 
             lock (updateTaskLock)
                 updateCheckTask = null;
+
+            return hasUpdates;
         }
 
-        protected virtual Task PerformUpdateCheck() => Task.CompletedTask;
+        /// <summary>
+        /// Performs an asynchronous check for application updates.
+        /// </summary>
+        /// <returns>Whether any update is waiting. May return true if an error occured (there is potentially an update available).</returns>
+        protected virtual Task<bool> PerformUpdateCheck() => Task.FromResult(false);
 
         private class UpdateCompleteNotification : SimpleNotification
         {