Fix osu!mania hold notes playing a sound at their tail in the editor

Closes #29584.

osu.Game.Rulesets.Mania/Beatmaps/ManiaBeatmapConverter.cs

@@ -6,7 +6,6 @@
 using System.Linq;
 using System.Collections.Generic;
 using System.Threading;
-using osu.Game.Audio;
 using osu.Game.Beatmaps;
 using osu.Game.Rulesets.Objects;
 using osu.Game.Rulesets.Objects.Types;
@@ -271,7 +270,7 @@ private Pattern generate()
                         Duration = endTimeData.Duration,
                         Column = column,
                         Samples = HitObject.Samples,
-                        NodeSamples = (HitObject as IHasRepeats)?.NodeSamples ?? defaultNodeSamples
+                        NodeSamples = (HitObject as IHasRepeats)?.NodeSamples ?? HoldNote.CreateDefaultNodeSamples(HitObject)
                     });
                 }
                 else if (HitObject is IHasXPosition)
@@ -286,16 +285,6 @@ private Pattern generate()
 
                 return pattern;
             }
-
-            /// <remarks>
-            /// osu!mania-specific beatmaps in stable only play samples at the start of the hold note.
-            /// </remarks>
-            private List<IList<HitSampleInfo>> defaultNodeSamples
-                => new List<IList<HitSampleInfo>>
-                {
-                    HitObject.Samples,
-                    new List<HitSampleInfo>()
-                };
         }
     }
 }

osu.Game.Rulesets.Mania/Objects/HoldNote.cs

@@ -7,6 +7,7 @@
 using System.Threading;
 using osu.Game.Audio;
 using osu.Game.Rulesets.Judgements;
+using osu.Game.Rulesets.Objects;
 using osu.Game.Rulesets.Objects.Types;
 using osu.Game.Rulesets.Scoring;
 
@@ -91,6 +92,10 @@ protected override void CreateNestedHitObjects(CancellationToken cancellationTok
         {
             base.CreateNestedHitObjects(cancellationToken);
 
+            // Generally node samples will be populated by ManiaBeatmapConverter, but in a case like the editor they may not be.
+            // Ensure they are set to a sane default here.
+            NodeSamples ??= CreateDefaultNodeSamples(this);
+
             AddNested(Head = new HeadNote
             {
                 StartTime = StartTime,
@@ -102,7 +107,7 @@ protected override void CreateNestedHitObjects(CancellationToken cancellationTok
             {
                 StartTime = EndTime,
                 Column = Column,
-                Samples = GetNodeSamples((NodeSamples?.Count - 1) ?? 1),
+                Samples = GetNodeSamples(NodeSamples.Count - 1),
             });
 
             AddNested(Body = new HoldNoteBody
@@ -116,7 +121,20 @@ protected override void CreateNestedHitObjects(CancellationToken cancellationTok
 
         protected override HitWindows CreateHitWindows() => HitWindows.Empty;
 
-        public IList<HitSampleInfo> GetNodeSamples(int nodeIndex) =>
+        public IList<HitSampleInfo> GetNodeSamples(int nodeIndex) => nodeIndex < NodeSamples?.Count ? NodeSamples[nodeIndex] : Samples;
-            nodeIndex < NodeSamples?.Count ? NodeSamples[nodeIndex] : Samples;
+
+        /// <summary>
+        /// Create the default note samples for a hold note, based off their main sample.
+        /// </summary>
+        /// <remarks>
+        /// By default, osu!mania beatmaps in only play samples at the start of the hold note.
+        /// </remarks>
+        /// <param name="obj">The object to use as a basis for the head sample.</param>
+        /// <returns>Defaults for assigning to <see cref="HoldNote.NodeSamples"/>.</returns>
+        public static List<IList<HitSampleInfo>> CreateDefaultNodeSamples(HitObject obj) => new List<IList<HitSampleInfo>>
+        {
+            obj.Samples,
+            new List<HitSampleInfo>(),
+        };
     }
 }