Prevent user from scrolling outside the timeline in the editor

osu.Game.Tests/Visual/TestCaseQuitButton.cs

@@ -44,13 +44,13 @@ private void load()
             {
                 exitAction = false;
                 InputManager.MoveMouseTo(quitButton);
-                InputManager.ButtonDown(MouseButton.Left);
+                InputManager.PressButton(MouseButton.Left);
             });
 
-            AddStep("Early release", () => InputManager.ButtonUp(MouseButton.Left));
+            AddStep("Early release", () => InputManager.ReleaseButton(MouseButton.Left));
             AddAssert("action not triggered", () => !exitAction);
 
-            AddStep("Trigger exit action", () => InputManager.ButtonDown(MouseButton.Left));
+            AddStep("Trigger exit action", () => InputManager.PressButton(MouseButton.Left));
             AddUntilStep(() => exitAction, $"{nameof(quitButton.Action)} was triggered");
         }
     }

osu.Game/Screens/Edit/Editor.cs

@@ -48,7 +48,7 @@ private void load(OsuColour colours)
         {
             // TODO: should probably be done at a RulesetContainer level to share logic with Player.
             var sourceClock = (IAdjustableClock)Beatmap.Value.Track ?? new StopwatchClock();
-            clock = new EditorClock(Beatmap.Value.Beatmap.ControlPointInfo, beatDivisor) { IsCoupled = false };
+            clock = new EditorClock(Beatmap, beatDivisor) { IsCoupled = false };
             clock.ChangeSource(sourceClock);
 
             dependencies.CacheAs<IFrameBasedClock>(clock);

osu.Game/Screens/Edit/EditorClock.cs

@@ -3,10 +3,13 @@
 
 using System;
 using System.Linq;
+using osu.Framework.Configuration;
 using osu.Framework.MathUtils;
 using osu.Framework.Timing;
+using osu.Game.Beatmaps;
 using osu.Game.Beatmaps.ControlPoints;
 using osu.Game.Screens.Edit.Screens.Compose;
+using OpenTK;
 
 namespace osu.Game.Screens.Edit
 {
@@ -15,15 +18,26 @@ namespace osu.Game.Screens.Edit
     /// </summary>
     public class EditorClock : DecoupleableInterpolatingFramedClock
     {
+        public readonly double TrackLength;
+
         public ControlPointInfo ControlPointInfo;
 
         private readonly BindableBeatDivisor beatDivisor;
 
-        public EditorClock(ControlPointInfo controlPointInfo, BindableBeatDivisor beatDivisor)
+        public EditorClock(Bindable<WorkingBeatmap> beatmap, BindableBeatDivisor beatDivisor)
+        {
+            this.beatDivisor = beatDivisor;
+
+            ControlPointInfo = beatmap.Value.Beatmap.ControlPointInfo;
+            TrackLength = beatmap.Value.Track.Length;
+        }
+
+        public EditorClock(ControlPointInfo controlPointInfo, double trackLength, BindableBeatDivisor beatDivisor)
         {
             this.beatDivisor = beatDivisor;
 
             ControlPointInfo = controlPointInfo;
+            TrackLength = trackLength;
         }
 
         /// <summary>
@@ -111,6 +125,8 @@ private void seek(int direction, bool snapped)
             if (seekTime > nextTimingPoint?.Time)
                 seekTime = nextTimingPoint.Time;
 
+            // Ensure the sought point is within the boundaries
+            seekTime = MathHelper.Clamp(seekTime, 0, TrackLength);
             Seek(seekTime);
         }
     }

osu.Game/Tests/Visual/EditorClockTestCase.cs

@@ -29,7 +29,7 @@ protected override IReadOnlyDependencyContainer CreateLocalDependencies(IReadOnl
 
         protected EditorClockTestCase()
         {
-            Clock = new EditorClock(new ControlPointInfo(), BeatDivisor) { IsCoupled = false };
+            Clock = new EditorClock(new ControlPointInfo(), 5000, BeatDivisor) { IsCoupled = false };
         }
 
         [BackgroundDependencyLoader]