From 04ac414249a30de3ea34a734a2c0e08183a27af7 Mon Sep 17 00:00:00 2001
From: smoogipoo <smoogipoo@smgi.me>
Date: Tue, 1 Oct 2019 13:48:56 +0900
Subject: [PATCH] Fix memory leaks due to audio track recycle order

---
 osu.Game/Beatmaps/BindableBeatmap.cs  | 23 -----------------------
 osu.Game/OsuGameBase.cs               |  6 ++++++
 osu.Game/Tests/Visual/OsuTestScene.cs |  9 ++++++---
 3 files changed, 12 insertions(+), 26 deletions(-)

diff --git a/osu.Game/Beatmaps/BindableBeatmap.cs b/osu.Game/Beatmaps/BindableBeatmap.cs
index af627cc6a9..39c633e282 100644
--- a/osu.Game/Beatmaps/BindableBeatmap.cs
+++ b/osu.Game/Beatmaps/BindableBeatmap.cs
@@ -1,7 +1,6 @@
 // Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
 // See the LICENCE file in the repository root for full licence text.
 
-using System.Diagnostics;
 using osu.Framework.Bindables;
 
 namespace osu.Game.Beatmaps
@@ -12,31 +11,9 @@ namespace osu.Game.Beatmaps
     /// </summary>
     public abstract class BindableBeatmap : NonNullableBindable<WorkingBeatmap>
     {
-        private WorkingBeatmap lastBeatmap;
-
         protected BindableBeatmap(WorkingBeatmap defaultValue)
             : base(defaultValue)
         {
-            BindValueChanged(b => updateAudioTrack(b.NewValue), true);
-        }
-
-        private void updateAudioTrack(WorkingBeatmap beatmap)
-        {
-            var trackLoaded = lastBeatmap?.TrackLoaded ?? false;
-
-            // compare to last beatmap as sometimes the two may share a track representation (optimisation, see WorkingBeatmap.TransferTo)
-            if (!trackLoaded || lastBeatmap?.Track != beatmap.Track)
-            {
-                if (trackLoaded)
-                {
-                    Debug.Assert(lastBeatmap != null);
-                    Debug.Assert(lastBeatmap.Track != null);
-
-                    lastBeatmap.RecycleTrack();
-                }
-            }
-
-            lastBeatmap = beatmap;
         }
     }
 }
diff --git a/osu.Game/OsuGameBase.cs b/osu.Game/OsuGameBase.cs
index 59a5e38b2c..a9a9693c76 100644
--- a/osu.Game/OsuGameBase.cs
+++ b/osu.Game/OsuGameBase.cs
@@ -203,6 +203,12 @@ namespace osu.Game
             Audio.Tracks.AddAdjustment(AdjustableProperty.Volume, new BindableDouble(0.8));
 
             beatmap = new OsuBindableBeatmap(defaultBeatmap);
+            beatmap.BindValueChanged(b => ScheduleAfterChildren(() =>
+            {
+                // compare to last beatmap as sometimes the two may share a track representation (optimisation, see WorkingBeatmap.TransferTo)
+                if (b.OldValue?.TrackLoaded == true && b.OldValue?.Track != b.NewValue?.Track)
+                    b.OldValue.RecycleTrack();
+            }));
 
             dependencies.CacheAs<IBindable<WorkingBeatmap>>(beatmap);
             dependencies.CacheAs(beatmap);
diff --git a/osu.Game/Tests/Visual/OsuTestScene.cs b/osu.Game/Tests/Visual/OsuTestScene.cs
index 8e98d51962..cf128e058f 100644
--- a/osu.Game/Tests/Visual/OsuTestScene.cs
+++ b/osu.Game/Tests/Visual/OsuTestScene.cs
@@ -73,10 +73,13 @@ namespace osu.Game.Tests.Visual
             // This is the earliest we can get OsuGameBase, which is used by the dummy working beatmap to find textures
             var working = new DummyWorkingBeatmap(parent.Get<AudioManager>(), parent.Get<TextureStore>());
 
-            beatmap = new OsuTestBeatmap(working)
+            beatmap = new OsuTestBeatmap(working) { Default = working };
+            beatmap.BindValueChanged(b => ScheduleAfterChildren(() =>
             {
-                Default = working
-            };
+                // compare to last beatmap as sometimes the two may share a track representation (optimisation, see WorkingBeatmap.TransferTo)
+                if (b.OldValue?.TrackLoaded == true && b.OldValue?.Track != b.NewValue?.Track)
+                    b.OldValue.RecycleTrack();
+            }));
 
             Dependencies = new DependencyContainer(base.CreateChildDependencies(parent));