And then everything became one

osu.Game/Tests/Visual/TestCaseMusicController.cs

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+// Copyright (c) 2007-2017 ppy Pty Ltd <contact@ppy.sh>.
+// Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
+
+using osu.Framework.Allocation;
+using osu.Framework.Configuration;
+using osu.Framework.Graphics;
+using osu.Framework.Graphics.Containers;
+using osu.Framework.Timing;
+using osu.Game.Beatmaps;
+using osu.Game.Overlays;
+
+namespace osu.Game.Tests.Visual
+{
+    internal class TestCaseMusicController : OsuTestCase
+    {
+        public override string Description => @"Tests music controller ui.";
+
+        private readonly Bindable<WorkingBeatmap> beatmapBacking = new Bindable<WorkingBeatmap>();
+
+        public TestCaseMusicController()
+        {
+            Clock = new FramedClock();
+
+            var mc = new MusicController
+            {
+                Origin = Anchor.Centre,
+                Anchor = Anchor.Centre
+            };
+            Add(mc);
+
+            AddToggleStep(@"toggle visibility", state => mc.State = state ? Visibility.Visible : Visibility.Hidden);
+            AddStep(@"show", () => mc.State = Visibility.Visible);
+            AddToggleStep(@"toggle beatmap lock", state => beatmapBacking.Disabled = state);
+        }
+
+        [BackgroundDependencyLoader]
+        private void load(OsuGameBase game)
+        {
+            beatmapBacking.BindTo(game.Beatmap);
+        }
+    }
+}