Change IBeatSyncProvider.Clock to always be non-null

osu.Game.Tests/Visual/UserInterface/TestSceneBeatSyncedContainer.cs

@@ -5,7 +5,6 @@
 
 using System;
 using System.Collections.Generic;
-using System.Diagnostics;
 using System.Linq;
 using NUnit.Framework;
 using osu.Framework.Audio.Track;
@@ -283,8 +282,6 @@ namespace osu.Game.Tests.Visual.UserInterface
 
                 if (ReferenceEquals(timingPoints[^1], current))
                 {
-                    Debug.Assert(BeatSyncSource.Clock != null);
-
                     return (int)Math.Ceiling((BeatSyncSource.Clock.CurrentTime - current.Time) / current.BeatLength);
                 }
 
@@ -295,8 +292,6 @@ namespace osu.Game.Tests.Visual.UserInterface
             {
                 base.Update();
 
-                Debug.Assert(BeatSyncSource.Clock != null);
-
                 timeUntilNextBeat.Value = TimeUntilNextBeat;
                 timeSinceLastBeat.Value = TimeSinceLastBeat;
                 currentTime.Value = BeatSyncSource.Clock.CurrentTime;

osu.Game/Beatmaps/BeatSyncProviderExtensions.cs

@@ -5,14 +5,9 @@ namespace osu.Game.Beatmaps
 {
     public static class BeatSyncProviderExtensions
     {
-        /// <summary>
-        /// Check whether beat sync is currently available.
-        /// </summary>
-        public static bool CheckBeatSyncAvailable(this IBeatSyncProvider provider) => provider.Clock != null;
-
         /// <summary>
         /// Whether the beat sync provider is currently in a kiai section. Should make everything more epic.
         /// </summary>
-        public static bool CheckIsKiaiTime(this IBeatSyncProvider provider) => provider.Clock != null && provider.ControlPoints?.EffectPointAt(provider.Clock.CurrentTime).KiaiMode == true;
+        public static bool CheckIsKiaiTime(this IBeatSyncProvider provider) => provider.ControlPoints?.EffectPointAt(provider.Clock.CurrentTime).KiaiMode == true;
     }
 }

osu.Game/Beatmaps/IBeatSyncProvider.cs

@@ -24,6 +24,6 @@ namespace osu.Game.Beatmaps
         /// <summary>
         /// Access a clock currently responsible for providing beat sync. If <c>null</c>, no current provider is available.
         /// </summary>
-        IClock? Clock { get; }
+        IClock Clock { get; }
     }
 }

osu.Game/Graphics/Containers/BeatSyncedContainer.cs

@@ -2,7 +2,6 @@
 // See the LICENCE file in the repository root for full licence text.
 
 using System;
-using System.Diagnostics;
 using osu.Framework.Allocation;
 using osu.Framework.Audio.Track;
 using osu.Framework.Graphics.Containers;
@@ -86,14 +85,12 @@ namespace osu.Game.Graphics.Containers
             TimingControlPoint timingPoint;
             EffectControlPoint effectPoint;
 
-            IsBeatSyncedWithTrack = BeatSyncSource.CheckBeatSyncAvailable() && BeatSyncSource.Clock?.IsRunning == true;
+            IsBeatSyncedWithTrack = BeatSyncSource.Clock.IsRunning;
 
             double currentTrackTime;
 
             if (IsBeatSyncedWithTrack)
             {
-                Debug.Assert(BeatSyncSource.Clock != null);
-
                 currentTrackTime = BeatSyncSource.Clock.CurrentTime + EarlyActivationMilliseconds;
 
                 timingPoint = BeatSyncSource.ControlPoints?.TimingPointAt(currentTrackTime) ?? TimingControlPoint.DEFAULT;

osu.Game/Rulesets/Mods/MetronomeBeat.cs

@@ -36,7 +36,7 @@ namespace osu.Game.Rulesets.Mods
             int timeSignature = timingPoint.TimeSignature.Numerator;
 
             // play metronome from one measure before the first object.
-            if (BeatSyncSource.Clock?.CurrentTime < firstHitTime - timingPoint.BeatLength * timeSignature)
+            if (BeatSyncSource.Clock.CurrentTime < firstHitTime - timingPoint.BeatLength * timeSignature)
                 return;
 
             sample.Frequency.Value = beatIndex % timeSignature == 0 ? 1 : 0.5f;

osu.Game/Screens/Edit/Timing/MetronomeDisplay.cs

@@ -240,7 +240,7 @@ namespace osu.Game.Screens.Edit.Timing
         {
             base.Update();
 
-            if (BeatSyncSource.ControlPoints == null || BeatSyncSource.Clock == null)
+            if (BeatSyncSource.ControlPoints == null)
                 return;
 
             metronomeClock.Rate = IsBeatSyncedWithTrack ? BeatSyncSource.Clock.Rate : 1;
@@ -259,7 +259,7 @@ namespace osu.Game.Screens.Edit.Timing
                 this.TransformBindableTo(interpolatedBpm, (int)Math.Round(timingPoint.BPM), 600, Easing.OutQuint);
             }
 
-            if (BeatSyncSource.Clock?.IsRunning != true && isSwinging)
+            if (!BeatSyncSource.Clock.IsRunning && isSwinging)
             {
                 swing.ClearTransforms(true);
 

osu.Game/Screens/Edit/Timing/TapButton.cs

@@ -310,7 +310,7 @@ namespace osu.Game.Screens.Edit.Timing
             }
 
             double averageBeatLength = (tapTimings.Last() - tapTimings.Skip(initial_taps_to_ignore).First()) / (tapTimings.Count - initial_taps_to_ignore - 1);
-            double clockRate = beatSyncSource?.Clock?.Rate ?? 1;
+            double clockRate = beatSyncSource?.Clock.Rate ?? 1;
 
             double bpm = Math.Round(60000 / averageBeatLength / clockRate);
 

osu.Game/Screens/Menu/LogoVisualisation.cs

@@ -102,7 +102,6 @@ namespace osu.Game.Screens.Menu
             for (int i = 0; i < temporalAmplitudes.Length; i++)
                 temporalAmplitudes[i] = 0;
 
-            if (beatSyncProvider.Clock != null)
             addAmplitudesFromSource(beatSyncProvider);
 
             foreach (var source in amplitudeSources)

osu.Game/Storyboards/Drawables/DrawableStoryboardAnimation.cs

@@ -128,7 +128,7 @@ namespace osu.Game.Storyboards.Drawables
             //
             // In the case of storyboard animations, we want to synchronise with game time perfectly
             // so let's get a correct time based on gameplay clock and earliest transform.
-            PlaybackPosition = (beatSyncProvider.Clock?.CurrentTime ?? Clock.CurrentTime) - Animation.EarliestTransformTime;
+            PlaybackPosition = beatSyncProvider.Clock.CurrentTime - Animation.EarliestTransformTime;
         }
 
         private void skinSourceChanged()