Merge branch 'master' into skin/argon-song-progress-cleaner

osu.Game.Rulesets.Catch/Beatmaps/CatchBeatmap.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using System.Collections.Generic;
 using System.Linq;
 using osu.Game.Beatmaps;

osu.Game.Rulesets.Catch/Beatmaps/CatchBeatmapConverter.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Game.Beatmaps;
 using osu.Game.Rulesets.Catch.Objects;
 using System.Collections.Generic;

osu.Game.Rulesets.Catch/Beatmaps/CatchBeatmapProcessor.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using System;
 using System.Collections.Generic;
 using System.Linq;

osu.Game.Rulesets.Catch/Difficulty/CatchDifficultyCalculator.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using System;
 using System.Collections.Generic;
 using System.Linq;
@@ -51,7 +49,7 @@ namespace osu.Game.Rulesets.Catch.Difficulty
 
         protected override IEnumerable<DifficultyHitObject> CreateDifficultyHitObjects(IBeatmap beatmap, double clockRate)
         {
-            CatchHitObject lastObject = null;
+            CatchHitObject? lastObject = null;
 
             List<DifficultyHitObject> objects = new List<DifficultyHitObject>();
 

osu.Game.Rulesets.Catch/Difficulty/CatchPerformanceAttributes.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Game.Rulesets.Difficulty;
 
 namespace osu.Game.Rulesets.Catch.Difficulty

osu.Game.Rulesets.Catch/Difficulty/CatchPerformanceCalculator.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using System;
 using System.Collections.Generic;
 using System.Linq;

osu.Game.Rulesets.Catch/Difficulty/Preprocessing/CatchDifficultyHitObject.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using System;
 using System.Collections.Generic;
 using osu.Game.Rulesets.Catch.Objects;

osu.Game.Rulesets.Catch/Difficulty/Skills/Movement.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using System;
 using osu.Game.Rulesets.Catch.Difficulty.Preprocessing;
 using osu.Game.Rulesets.Difficulty.Preprocessing;

osu.Game.Rulesets.Catch/Edit/BananaShowerCompositionTool.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Framework.Graphics;
 using osu.Game.Beatmaps;
 using osu.Game.Rulesets.Catch.Edit.Blueprints;

osu.Game.Rulesets.Catch/Edit/Blueprints/BananaShowerPlacementBlueprint.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using System;
 using osu.Framework.Input.Events;
 using osu.Game.Rulesets.Catch.Edit.Blueprints.Components;

osu.Game.Rulesets.Catch/Edit/Blueprints/BananaShowerSelectionBlueprint.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Game.Rulesets.Catch.Objects;
 
 namespace osu.Game.Rulesets.Catch.Edit.Blueprints

osu.Game.Rulesets.Catch/Edit/Blueprints/CatchPlacementBlueprint.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Framework.Allocation;
 using osu.Game.Rulesets.Catch.Objects;
 using osu.Game.Rulesets.Edit;
@@ -20,7 +18,7 @@ namespace osu.Game.Rulesets.Catch.Edit.Blueprints
         protected ScrollingHitObjectContainer HitObjectContainer => (ScrollingHitObjectContainer)playfield.HitObjectContainer;
 
         [Resolved]
-        private Playfield playfield { get; set; }
+        private Playfield playfield { get; set; } = null!;
 
         public CatchPlacementBlueprint()
             : base(new THitObject())

osu.Game.Rulesets.Catch/Edit/Blueprints/CatchSelectionBlueprint.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Framework.Allocation;
 using osu.Game.Rulesets.Catch.Objects;
 using osu.Game.Rulesets.Edit;
@@ -31,7 +29,7 @@ namespace osu.Game.Rulesets.Catch.Edit.Blueprints
         protected ScrollingHitObjectContainer HitObjectContainer => (ScrollingHitObjectContainer)playfield.HitObjectContainer;
 
         [Resolved]
-        private Playfield playfield { get; set; }
+        private Playfield playfield { get; set; } = null!;
 
         protected CatchSelectionBlueprint(THitObject hitObject)
             : base(hitObject)

osu.Game.Rulesets.Catch/Edit/Blueprints/Components/EditablePath.cs

@@ -1,13 +1,10 @@
 // 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.
 
-#nullable disable
-
 using System;
 using System.Collections.Generic;
 using System.Diagnostics;
 using System.Linq;
-using JetBrains.Annotations;
 using osu.Framework.Allocation;
 using osu.Framework.Graphics;
 using osu.Framework.Graphics.Containers;
@@ -42,9 +39,8 @@ namespace osu.Game.Rulesets.Catch.Edit.Blueprints.Components
 
         private readonly List<VertexState> previousVertexStates = new List<VertexState>();
 
-        [Resolved(CanBeNull = true)]
+        [Resolved]
-        [CanBeNull]
+        private IBeatSnapProvider? beatSnapProvider { get; set; }
-        private IBeatSnapProvider beatSnapProvider { get; set; }
 
         protected EditablePath(Func<float, double> positionToTime)
         {

osu.Game.Rulesets.Catch/Edit/Blueprints/Components/FruitOutline.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Framework.Allocation;
 using osu.Framework.Graphics;
 using osu.Framework.Graphics.Containers;

osu.Game.Rulesets.Catch/Edit/Blueprints/Components/NestedOutlineContainer.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using System.Collections.Generic;
 using System.Linq;
 using osu.Framework.Graphics;

osu.Game.Rulesets.Catch/Edit/Blueprints/Components/PlacementEditablePath.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using System;
 using osu.Game.Rulesets.Catch.Objects;
 using osuTK;

osu.Game.Rulesets.Catch/Edit/Blueprints/Components/ScrollingPath.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using System.Collections.Generic;
 using System.Linq;
 using osu.Framework.Graphics;

osu.Game.Rulesets.Catch/Edit/Blueprints/Components/SelectionEditablePath.cs

@@ -1,12 +1,9 @@
 // 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.
 
-#nullable disable
-
 using System;
 using System.Collections.Generic;
 using System.Linq;
-using JetBrains.Annotations;
 using osu.Framework.Allocation;
 using osu.Framework.Graphics.Cursor;
 using osu.Framework.Graphics.UserInterface;
@@ -25,9 +22,8 @@ namespace osu.Game.Rulesets.Catch.Edit.Blueprints.Components
         // To handle when the editor is scrolled while dragging.
         private Vector2 dragStartPosition;
 
-        [Resolved(CanBeNull = true)]
+        [Resolved]
-        [CanBeNull]
+        private IEditorChangeHandler? changeHandler { get; set; }
-        private IEditorChangeHandler changeHandler { get; set; }
 
         public SelectionEditablePath(Func<float, double> positionToTime)
             : base(positionToTime)

osu.Game.Rulesets.Catch/Edit/Blueprints/Components/TimeSpanOutline.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using System;
 using osu.Framework.Allocation;
 using osu.Framework.Graphics;

osu.Game.Rulesets.Catch/Edit/Blueprints/Components/VertexPiece.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Framework.Allocation;
 using osu.Framework.Extensions.Color4Extensions;
 using osu.Framework.Graphics;
@@ -15,7 +13,7 @@ namespace osu.Game.Rulesets.Catch.Edit.Blueprints.Components
     public partial class VertexPiece : Circle
     {
         [Resolved]
-        private OsuColour osuColour { get; set; }
+        private OsuColour osuColour { get; set; } = null!;
 
         public VertexPiece()
         {

osu.Game.Rulesets.Catch/Edit/Blueprints/FruitPlacementBlueprint.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Framework.Input.Events;
 using osu.Game.Rulesets.Catch.Edit.Blueprints.Components;
 using osu.Game.Rulesets.Catch.Objects;

osu.Game.Rulesets.Catch/Edit/Blueprints/FruitSelectionBlueprint.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Game.Rulesets.Catch.Edit.Blueprints.Components;
 using osu.Game.Rulesets.Catch.Objects;
 

osu.Game.Rulesets.Catch/Edit/Blueprints/JuiceStreamPlacementBlueprint.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Framework.Graphics;
 using osu.Framework.Input;
 using osu.Framework.Input.Events;
@@ -24,7 +22,7 @@ namespace osu.Game.Rulesets.Catch.Edit.Blueprints
 
         private int lastEditablePathId = -1;
 
-        private InputManager inputManager;
+        private InputManager inputManager = null!;
 
         public JuiceStreamPlacementBlueprint()
         {

osu.Game.Rulesets.Catch/Edit/Blueprints/JuiceStreamSelectionBlueprint.cs

@@ -1,11 +1,8 @@
 // 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.
 
-#nullable disable
-
 using System.Collections.Generic;
 using System.Linq;
-using JetBrains.Annotations;
 using osu.Framework.Allocation;
 using osu.Framework.Caching;
 using osu.Framework.Graphics;
@@ -53,9 +50,8 @@ namespace osu.Game.Rulesets.Catch.Edit.Blueprints
 
         private Vector2 rightMouseDownPosition;
 
-        [Resolved(CanBeNull = true)]
+        [Resolved]
-        [CanBeNull]
+        private EditorBeatmap? editorBeatmap { get; set; }
-        private EditorBeatmap editorBeatmap { get; set; }
 
         public JuiceStreamSelectionBlueprint(JuiceStream hitObject)
             : base(hitObject)

osu.Game.Rulesets.Catch/Edit/CatchBeatmapVerifier.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using System.Collections.Generic;
 using System.Linq;
 using osu.Game.Rulesets.Catch.Edit.Checks;

osu.Game.Rulesets.Catch/Edit/CatchBlueprintContainer.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Game.Rulesets.Catch.Edit.Blueprints;
 using osu.Game.Rulesets.Catch.Objects;
 using osu.Game.Rulesets.Edit;
@@ -20,7 +18,7 @@ namespace osu.Game.Rulesets.Catch.Edit
 
         protected override SelectionHandler<HitObject> CreateSelectionHandler() => new CatchSelectionHandler();
 
-        public override HitObjectSelectionBlueprint CreateHitObjectBlueprintFor(HitObject hitObject)
+        public override HitObjectSelectionBlueprint? CreateHitObjectBlueprintFor(HitObject hitObject)
         {
             switch (hitObject)
             {

osu.Game.Rulesets.Catch/Edit/CatchDistanceSnapGrid.cs

@@ -1,12 +1,9 @@
 // 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.
 
-#nullable disable
-
 using System;
 using System.Collections.Generic;
 using System.Linq;
-using JetBrains.Annotations;
 using osu.Framework.Allocation;
 using osu.Framework.Graphics;
 using osu.Framework.Graphics.Containers;
@@ -39,7 +36,7 @@ namespace osu.Game.Rulesets.Catch.Edit
         private readonly List<Vector2[]> verticalLineVertices = new List<Vector2[]>();
 
         [Resolved]
-        private Playfield playfield { get; set; }
+        private Playfield playfield { get; set; } = null!;
 
         private ScrollingHitObjectContainer hitObjectContainer => (ScrollingHitObjectContainer)playfield.HitObjectContainer;
 
@@ -106,8 +103,7 @@ namespace osu.Game.Rulesets.Catch.Edit
             }
         }
 
-        [CanBeNull]
+        public SnapResult? GetSnappedPosition(Vector2 screenSpacePosition)
-        public SnapResult GetSnappedPosition(Vector2 screenSpacePosition)
         {
             double time = hitObjectContainer.TimeAtScreenSpacePosition(screenSpacePosition);
 

osu.Game.Rulesets.Catch/Edit/CatchEditorPlayfield.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Game.Beatmaps;
 using osu.Game.Rulesets.Catch.UI;
 

osu.Game.Rulesets.Catch/Edit/CatchHitObjectComposer.cs

@@ -1,12 +1,9 @@
 // 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.
 
-#nullable disable
-
 using System;
 using System.Collections.Generic;
 using System.Linq;
-using JetBrains.Annotations;
 using osu.Framework.Allocation;
 using osu.Framework.Bindables;
 using osu.Framework.Extensions.EnumExtensions;
@@ -32,9 +29,9 @@ namespace osu.Game.Rulesets.Catch.Edit
     {
         private const float distance_snap_radius = 50;
 
-        private CatchDistanceSnapGrid distanceSnapGrid;
+        private CatchDistanceSnapGrid distanceSnapGrid = null!;
 
-        private InputManager inputManager;
+        private InputManager inputManager = null!;
 
         private readonly BindableDouble timeRangeMultiplier = new BindableDouble(1)
         {
@@ -117,7 +114,7 @@ namespace osu.Game.Rulesets.Catch.Edit
             return base.OnPressed(e);
         }
 
-        protected override DrawableRuleset<CatchHitObject> CreateDrawableRuleset(Ruleset ruleset, IBeatmap beatmap, IReadOnlyList<Mod> mods = null) =>
+        protected override DrawableRuleset<CatchHitObject> CreateDrawableRuleset(Ruleset ruleset, IBeatmap beatmap, IReadOnlyList<Mod>? mods = null) =>
             new DrawableCatchEditorRuleset(ruleset, beatmap, mods)
             {
                 TimeRangeMultiplier = { BindTarget = timeRangeMultiplier, }
@@ -150,8 +147,7 @@ namespace osu.Game.Rulesets.Catch.Edit
 
         protected override ComposeBlueprintContainer CreateBlueprintContainer() => new CatchBlueprintContainer(this);
 
-        [CanBeNull]
+        private PalpableCatchHitObject? getLastSnappableHitObject(double time)
-        private PalpableCatchHitObject getLastSnappableHitObject(double time)
         {
             var hitObject = EditorBeatmap.HitObjects.OfType<CatchHitObject>().LastOrDefault(h => h.GetEndTime() < time && !(h is BananaShower));
 
@@ -168,8 +164,7 @@ namespace osu.Game.Rulesets.Catch.Edit
             }
         }
 
-        [CanBeNull]
+        private PalpableCatchHitObject? getDistanceSnapGridSourceHitObject()
-        private PalpableCatchHitObject getDistanceSnapGridSourceHitObject()
         {
             switch (BlueprintContainer.CurrentTool)
             {
@@ -188,6 +183,7 @@ namespace osu.Game.Rulesets.Catch.Edit
                     if (EditorBeatmap.PlacementObject.Value is JuiceStream)
                     {
                         // Juice stream path is not subject to snapping.
+                        if (BlueprintContainer.CurrentPlacement.PlacementActive is PlacementBlueprint.PlacementState.Active)
                             return null;
                     }
 

osu.Game.Rulesets.Catch/Edit/CatchHitObjectUtils.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using System.Collections.Generic;
 using System.Linq;
 using osu.Game.Rulesets.Catch.Objects;

osu.Game.Rulesets.Catch/Edit/CatchSelectionHandler.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using System;
 using System.Collections.Generic;
 using System.Linq;
@@ -23,7 +21,7 @@ namespace osu.Game.Rulesets.Catch.Edit
         protected ScrollingHitObjectContainer HitObjectContainer => (ScrollingHitObjectContainer)playfield.HitObjectContainer;
 
         [Resolved]
-        private Playfield playfield { get; set; }
+        private Playfield playfield { get; set; } = null!;
 
         public override bool HandleMovement(MoveSelectionEvent<HitObject> moveEvent)
         {

osu.Game.Rulesets.Catch/Edit/DrawableCatchEditorRuleset.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using System.Collections.Generic;
 using osu.Framework.Bindables;
 using osu.Game.Beatmaps;
@@ -16,7 +14,7 @@ namespace osu.Game.Rulesets.Catch.Edit
     {
         public readonly BindableDouble TimeRangeMultiplier = new BindableDouble(1);
 
-        public DrawableCatchEditorRuleset(Ruleset ruleset, IBeatmap beatmap, IReadOnlyList<Mod> mods = null)
+        public DrawableCatchEditorRuleset(Ruleset ruleset, IBeatmap beatmap, IReadOnlyList<Mod>? mods = null)
             : base(ruleset, beatmap, mods)
         {
         }

osu.Game.Rulesets.Catch/Edit/FruitCompositionTool.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Framework.Graphics;
 using osu.Game.Beatmaps;
 using osu.Game.Rulesets.Catch.Edit.Blueprints;

osu.Game.Rulesets.Catch/Edit/JuiceStreamCompositionTool.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Framework.Graphics;
 using osu.Game.Beatmaps;
 using osu.Game.Rulesets.Catch.Edit.Blueprints;

osu.Game.Rulesets.Catch/Judgements/CatchBananaJudgement.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Game.Rulesets.Judgements;
 using osu.Game.Rulesets.Scoring;
 

osu.Game.Rulesets.Catch/Judgements/CatchDropletJudgement.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Game.Rulesets.Scoring;
 
 namespace osu.Game.Rulesets.Catch.Judgements

osu.Game.Rulesets.Catch/Judgements/CatchJudgement.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Game.Rulesets.Judgements;
 using osu.Game.Rulesets.Objects.Types;
 using osu.Game.Rulesets.Scoring;

osu.Game.Rulesets.Catch/Judgements/CatchJudgementResult.cs

@@ -1,9 +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.
 
-#nullable disable
-
-using JetBrains.Annotations;
 using osu.Game.Rulesets.Catch.UI;
 using osu.Game.Rulesets.Judgements;
 using osu.Game.Rulesets.Objects;
@@ -22,7 +19,7 @@ namespace osu.Game.Rulesets.Catch.Judgements
         /// </summary>
         public bool CatcherHyperDash;
 
-        public CatchJudgementResult([NotNull] HitObject hitObject, [NotNull] Judgement judgement)
+        public CatchJudgementResult(HitObject hitObject, Judgement judgement)
             : base(hitObject, judgement)
         {
         }

osu.Game.Rulesets.Catch/Judgements/CatchTinyDropletJudgement.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Game.Rulesets.Scoring;
 
 namespace osu.Game.Rulesets.Catch.Judgements

osu.Game.Rulesets.Catch/Objects/BananaShower.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using System.Threading;
 using osu.Game.Rulesets.Judgements;
 using osu.Game.Rulesets.Objects.Types;

osu.Game.Rulesets.Catch/Objects/CatchHitObject.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using System;
 using Newtonsoft.Json;
 using osu.Framework.Bindables;

osu.Game.Rulesets.Catch/Objects/Drawables/CaughtBanana.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Game.Rulesets.Catch.Skinning.Default;
 
 namespace osu.Game.Rulesets.Catch.Objects.Drawables

osu.Game.Rulesets.Catch/Objects/Drawables/CaughtDroplet.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Game.Rulesets.Catch.Skinning.Default;
 
 namespace osu.Game.Rulesets.Catch.Objects.Drawables

osu.Game.Rulesets.Catch/Objects/Drawables/CaughtFruit.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Game.Rulesets.Catch.Skinning.Default;
 
 namespace osu.Game.Rulesets.Catch.Objects.Drawables

osu.Game.Rulesets.Catch/Objects/Drawables/CaughtObject.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using System;
 using osu.Framework.Allocation;
 using osu.Framework.Bindables;
@@ -19,7 +17,7 @@ namespace osu.Game.Rulesets.Catch.Objects.Drawables
     [Cached(typeof(IHasCatchObjectState))]
     public abstract partial class CaughtObject : SkinnableDrawable, IHasCatchObjectState
     {
-        public PalpableCatchHitObject HitObject { get; private set; }
+        public PalpableCatchHitObject HitObject { get; private set; } = null!;
         public Bindable<Color4> AccentColour { get; } = new Bindable<Color4>();
         public Bindable<bool> HyperDash { get; } = new Bindable<bool>();
         public Bindable<int> IndexInBeatmap { get; } = new Bindable<int>();

osu.Game.Rulesets.Catch/Objects/Drawables/DrawableBanana.cs

@@ -1,9 +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.
 
-#nullable disable
-
-using JetBrains.Annotations;
 using osu.Framework.Allocation;
 using osu.Framework.Graphics;
 using osu.Game.Rulesets.Catch.Skinning.Default;
@@ -18,7 +15,7 @@ namespace osu.Game.Rulesets.Catch.Objects.Drawables
         {
         }
 
-        public DrawableBanana([CanBeNull] Banana h)
+        public DrawableBanana(Banana? h)
             : base(h)
         {
         }

osu.Game.Rulesets.Catch/Objects/Drawables/DrawableBananaShower.cs

@@ -1,9 +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.
 
-#nullable disable
-
-using JetBrains.Annotations;
 using osu.Framework.Graphics;
 using osu.Framework.Graphics.Containers;
 using osu.Game.Rulesets.Objects.Drawables;
@@ -19,7 +16,7 @@ namespace osu.Game.Rulesets.Catch.Objects.Drawables
         {
         }
 
-        public DrawableBananaShower([CanBeNull] BananaShower s)
+        public DrawableBananaShower(BananaShower? s)
             : base(s)
         {
             RelativeSizeAxes = Axes.X;

osu.Game.Rulesets.Catch/Objects/Drawables/DrawableCatchHitObject.cs

@@ -53,6 +53,7 @@ namespace osu.Game.Rulesets.Catch.Objects.Drawables
             XOffsetBindable.UnbindFrom(HitObject.XOffsetBindable);
         }
 
+        [CanBeNull]
         public Func<CatchHitObject, bool> CheckPosition;
 
         protected override JudgementResult CreateResult(Judgement judgement) => new CatchJudgementResult(HitObject, judgement);

osu.Game.Rulesets.Catch/Objects/Drawables/DrawableDroplet.cs

@@ -1,9 +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.
 
-#nullable disable
-
-using JetBrains.Annotations;
 using osu.Framework.Allocation;
 using osu.Framework.Graphics;
 using osu.Game.Rulesets.Catch.Skinning.Default;
@@ -18,7 +15,7 @@ namespace osu.Game.Rulesets.Catch.Objects.Drawables
         {
         }
 
-        public DrawableDroplet([CanBeNull] CatchHitObject h)
+        public DrawableDroplet(CatchHitObject? h)
             : base(h)
         {
         }

osu.Game.Rulesets.Catch/Objects/Drawables/DrawableFruit.cs

@@ -1,9 +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.
 
-#nullable disable
-
-using JetBrains.Annotations;
 using osu.Framework.Allocation;
 using osu.Framework.Graphics;
 using osu.Game.Rulesets.Catch.Skinning.Default;
@@ -18,7 +15,7 @@ namespace osu.Game.Rulesets.Catch.Objects.Drawables
         {
         }
 
-        public DrawableFruit([CanBeNull] Fruit h)
+        public DrawableFruit(Fruit? h)
             : base(h)
         {
         }

osu.Game.Rulesets.Catch/Objects/Drawables/DrawableJuiceStream.cs

@@ -1,9 +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.
 
-#nullable disable
-
-using JetBrains.Annotations;
 using osu.Framework.Graphics;
 using osu.Framework.Graphics.Containers;
 using osu.Game.Rulesets.Objects.Drawables;
@@ -19,7 +16,7 @@ namespace osu.Game.Rulesets.Catch.Objects.Drawables
         {
         }
 
-        public DrawableJuiceStream([CanBeNull] JuiceStream s)
+        public DrawableJuiceStream(JuiceStream? s)
             : base(s)
         {
             RelativeSizeAxes = Axes.X;

osu.Game.Rulesets.Catch/Objects/Drawables/DrawablePalpableCatchHitObject.cs

@@ -1,9 +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.
 
-#nullable disable
-
-using JetBrains.Annotations;
 using osu.Framework.Allocation;
 using osu.Framework.Bindables;
 using osu.Framework.Graphics;
@@ -42,7 +39,7 @@ namespace osu.Game.Rulesets.Catch.Objects.Drawables
 
         public float DisplayRotation => ScalingContainer.Rotation;
 
-        protected DrawablePalpableCatchHitObject([CanBeNull] CatchHitObject h)
+        protected DrawablePalpableCatchHitObject(CatchHitObject? h)
             : base(h)
         {
             Origin = Anchor.Centre;

osu.Game.Rulesets.Catch/Objects/Drawables/DrawableTinyDroplet.cs

@@ -1,10 +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.
 
-#nullable disable
-
-using JetBrains.Annotations;
-
 namespace osu.Game.Rulesets.Catch.Objects.Drawables
 {
     public partial class DrawableTinyDroplet : DrawableDroplet
@@ -16,7 +12,7 @@ namespace osu.Game.Rulesets.Catch.Objects.Drawables
         {
         }
 
-        public DrawableTinyDroplet([CanBeNull] TinyDroplet h)
+        public DrawableTinyDroplet(TinyDroplet? h)
             : base(h)
         {
         }

osu.Game.Rulesets.Catch/Objects/Drawables/IHasCatchObjectState.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Framework.Bindables;
 using osuTK;
 using osuTK.Graphics;

osu.Game.Rulesets.Catch/Objects/Droplet.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Game.Rulesets.Catch.Judgements;
 using osu.Game.Rulesets.Judgements;
 

osu.Game.Rulesets.Catch/Objects/Fruit.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Game.Rulesets.Catch.Judgements;
 using osu.Game.Rulesets.Judgements;
 

osu.Game.Rulesets.Catch/Objects/FruitVisualRepresentation.cs

@@ -1,8 +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.
 
-#nullable disable
-
 namespace osu.Game.Rulesets.Catch.Objects
 {
     public enum FruitVisualRepresentation

osu.Game.Rulesets.Catch/Objects/JuiceStream.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using System;
 using System.Collections.Generic;
 using System.Linq;
@@ -142,15 +140,10 @@ namespace osu.Game.Rulesets.Catch.Objects
             set
             {
                 path.ControlPoints.Clear();
-                path.ExpectedDistance.Value = null;
-
-                if (value != null)
-                {
                 path.ControlPoints.AddRange(value.ControlPoints.Select(c => new PathControlPoint(c.Position, c.Type)));
                 path.ExpectedDistance.Value = value.ExpectedDistance.Value;
             }
         }
-        }
 
         public double Distance => Path.Distance;
 

osu.Game.Rulesets.Catch/Objects/PalpableCatchHitObject.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using Newtonsoft.Json;
 using osu.Framework.Bindables;
 using osu.Game.Rulesets.Objects;
@@ -34,13 +32,13 @@ namespace osu.Game.Rulesets.Catch.Objects
         /// </summary>
         public bool HyperDash => hyperDash.Value;
 
-        private CatchHitObject hyperDashTarget;
+        private CatchHitObject? hyperDashTarget;
 
         /// <summary>
         /// The target fruit if we are to initiate a hyperdash.
         /// </summary>
         [JsonIgnore]
-        public CatchHitObject HyperDashTarget
+        public CatchHitObject? HyperDashTarget
         {
             get => hyperDashTarget;
             set

osu.Game.Rulesets.Catch/Objects/TinyDroplet.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Game.Rulesets.Catch.Judgements;
 using osu.Game.Rulesets.Judgements;
 

osu.Game.Rulesets.Catch/Properties/AssemblyInfo.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using System.Runtime.CompilerServices;
 
 // We publish our internal attributes to other sub-projects of the framework.

osu.Game.Rulesets.Catch/Scoring/CatchScoreProcessor.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Game.Rulesets.Scoring;
 
 namespace osu.Game.Rulesets.Catch.Scoring

osu.Game.Rulesets.Catch/UI/CatchComboDisplay.cs

@@ -29,7 +29,7 @@ namespace osu.Game.Rulesets.Catch.UI
         {
         }
 
-        [Resolved(canBeNull: true)]
+        [Resolved]
         private Player? player { get; set; }
 
         protected override void LoadComplete()

osu.Game.Rulesets.Catch/UI/CatchPlayfield.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Framework.Allocation;
 using osu.Framework.Graphics;
 using osu.Game.Beatmaps;
@@ -39,9 +37,9 @@ namespace osu.Game.Rulesets.Catch.UI
             // only check the X position; handle all vertical space.
             base.ReceivePositionalInputAt(new Vector2(screenSpacePos.X, ScreenSpaceDrawQuad.Centre.Y));
 
-        internal Catcher Catcher { get; private set; }
+        internal Catcher Catcher { get; private set; } = null!;
 
-        internal CatcherArea CatcherArea { get; private set; }
+        internal CatcherArea CatcherArea { get; private set; } = null!;
 
         private readonly IBeatmapDifficultyInfo difficulty;
 

osu.Game.Rulesets.Catch/UI/CatchPlayfieldAdjustmentContainer.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Framework.Graphics;
 using osu.Framework.Graphics.Containers;
 using osu.Game.Rulesets.UI;

osu.Game.Rulesets.Catch/UI/CatchReplayRecorder.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using System.Collections.Generic;
 using osu.Game.Rulesets.Catch.Replays;
 using osu.Game.Rulesets.Replays;

osu.Game.Rulesets.Catch/UI/Catcher.cs

@@ -1,11 +1,9 @@
 // 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.
 
-#nullable disable
-
 using System;
+using System.Diagnostics;
 using System.Linq;
-using JetBrains.Annotations;
 using osu.Framework.Allocation;
 using osu.Framework.Bindables;
 using osu.Framework.Graphics;
@@ -123,7 +121,7 @@ namespace osu.Game.Rulesets.Catch.UI
         private double hyperDashModifier = 1;
         private int hyperDashDirection;
         private float hyperDashTargetPosition;
-        private Bindable<bool> hitLighting;
+        private Bindable<bool> hitLighting = null!;
 
         private readonly HitExplosionContainer hitExplosionContainer;
 
@@ -131,7 +129,7 @@ namespace osu.Game.Rulesets.Catch.UI
         private readonly DrawablePool<CaughtBanana> caughtBananaPool;
         private readonly DrawablePool<CaughtDroplet> caughtDropletPool;
 
-        public Catcher([NotNull] DroppedObjectContainer droppedObjectTarget, IBeatmapDifficultyInfo difficulty = null)
+        public Catcher(DroppedObjectContainer droppedObjectTarget, IBeatmapDifficultyInfo? difficulty = null)
         {
             this.droppedObjectTarget = droppedObjectTarget;
 
@@ -231,9 +229,8 @@ namespace osu.Game.Rulesets.Catch.UI
             // droplet doesn't affect the catcher state
             if (hitObject is TinyDroplet) return;
 
-            if (result.IsHit && hitObject.HyperDash)
+            if (result.IsHit && hitObject.HyperDashTarget is CatchHitObject target)
             {
-                var target = hitObject.HyperDashTarget;
                 double timeDifference = target.StartTime - hitObject.StartTime;
                 double positionDifference = target.EffectiveX - X;
                 double velocity = positionDifference / Math.Max(1.0, timeDifference - 1000.0 / 60.0);
@@ -385,7 +382,7 @@ namespace osu.Game.Rulesets.Catch.UI
         private void addLighting(JudgementResult judgementResult, Color4 colour, float x) =>
             hitExplosionContainer.Add(new HitExplosionEntry(Time.Current, judgementResult, colour, x));
 
-        private CaughtObject getCaughtObject(PalpableCatchHitObject source)
+        private CaughtObject? getCaughtObject(PalpableCatchHitObject source)
         {
             switch (source)
             {
@@ -406,6 +403,7 @@ namespace osu.Game.Rulesets.Catch.UI
         private CaughtObject getDroppedObject(CaughtObject caughtObject)
         {
             var droppedObject = getCaughtObject(caughtObject.HitObject);
+            Debug.Assert(droppedObject != null);
 
             droppedObject.CopyStateFrom(caughtObject);
             droppedObject.Anchor = Anchor.TopLeft;

osu.Game.Rulesets.Catch/UI/CatcherAnimationState.cs

@@ -1,8 +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.
 
-#nullable disable
-
 namespace osu.Game.Rulesets.Catch.UI
 {
     public enum CatcherAnimationState

osu.Game.Rulesets.Catch/UI/CatcherArea.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using System;
 using osu.Framework.Graphics;
 using osu.Framework.Graphics.Containers;
@@ -35,7 +33,7 @@ namespace osu.Game.Rulesets.Catch.UI
 
         private readonly CatcherTrailDisplay catcherTrails;
 
-        private Catcher catcher;
+        private Catcher catcher = null!;
 
         /// <summary>
         /// <c>-1</c> when only left button is pressed.

osu.Game.Rulesets.Catch/UI/CatcherTrail.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Framework.Graphics;
 using osu.Framework.Timing;
 using osu.Game.Rulesets.Objects.Pooling;

osu.Game.Rulesets.Catch/UI/CatcherTrailAnimation.cs

@@ -1,8 +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.
 
-#nullable disable
-
 namespace osu.Game.Rulesets.Catch.UI
 {
     public enum CatcherTrailAnimation

osu.Game.Rulesets.Catch/UI/CatcherTrailDisplay.cs

@@ -1,10 +1,9 @@
 // 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.
 
-#nullable disable
-
 using System;
 using osu.Framework.Allocation;
+using osu.Framework.Extensions.ObjectExtensions;
 using osu.Framework.Graphics;
 using osu.Framework.Graphics.Containers;
 using osu.Framework.Graphics.Pooling;
@@ -41,7 +40,7 @@ namespace osu.Game.Rulesets.Catch.UI
         private readonly Container<CatcherTrail> hyperDashAfterImages;
 
         [Resolved]
-        private ISkinSource skin { get; set; }
+        private ISkinSource skin { get; set; } = null!;
 
         public CatcherTrailDisplay()
         {
@@ -130,7 +129,7 @@ namespace osu.Game.Rulesets.Catch.UI
         {
             base.Dispose(isDisposing);
 
-            if (skin != null)
+            if (skin.IsNotNull())
                 skin.SourceChanged -= skinSourceChanged;
         }
     }

osu.Game.Rulesets.Catch/UI/CatcherTrailEntry.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Framework.Graphics.Performance;
 using osuTK;
 

osu.Game.Rulesets.Catch/UI/Direction.cs

@@ -1,8 +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.
 
-#nullable disable
-
 namespace osu.Game.Rulesets.Catch.UI
 {
     public enum Direction

osu.Game.Rulesets.Catch/UI/DrawableCatchRuleset.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using System.Collections.Generic;
 using System.Linq;
 using osu.Framework.Allocation;
@@ -27,7 +25,7 @@ namespace osu.Game.Rulesets.Catch.UI
 
         protected override bool UserScrollSpeedAdjustment => false;
 
-        public DrawableCatchRuleset(Ruleset ruleset, IBeatmap beatmap, IReadOnlyList<Mod> mods = null)
+        public DrawableCatchRuleset(Ruleset ruleset, IBeatmap beatmap, IReadOnlyList<Mod>? mods = null)
             : base(ruleset, beatmap, mods)
         {
             Direction.Value = ScrollingDirection.Down;
@@ -54,6 +52,6 @@ namespace osu.Game.Rulesets.Catch.UI
 
         protected override PassThroughInputManager CreateInputManager() => new CatchInputManager(Ruleset.RulesetInfo);
 
-        public override DrawableHitObject<CatchHitObject> CreateDrawableRepresentation(CatchHitObject h) => null;
+        public override DrawableHitObject<CatchHitObject>? CreateDrawableRepresentation(CatchHitObject h) => null;
     }
 }

osu.Game.Rulesets.Catch/UI/DroppedObjectContainer.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Framework.Graphics;
 using osu.Framework.Graphics.Containers;
 using osu.Game.Rulesets.Catch.Objects.Drawables;

osu.Game.Rulesets.Catch/UI/HitExplosionContainer.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Framework.Graphics;
 using osu.Framework.Graphics.Pooling;
 using osu.Game.Rulesets.Objects.Pooling;

osu.Game.Rulesets.Catch/UI/ICatchComboCounter.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Framework.Graphics;
 using osuTK.Graphics;
 

osu.Game.Rulesets.Catch/UI/SkinnableCatcher.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Framework.Allocation;
 using osu.Framework.Bindables;
 using osu.Framework.Graphics;

osu.Game.Rulesets.Mania.Tests/Editor/TestScenePlacementBeforeTrackStart.cs

@@ -0,0 +1,30 @@
+// 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.Linq;
+using NUnit.Framework;
+using osu.Framework.Graphics.Containers;
+using osu.Framework.Testing;
+using osu.Game.Tests.Visual;
+using osuTK.Input;
+
+namespace osu.Game.Rulesets.Mania.Tests.Editor
+{
+    public partial class TestScenePlacementBeforeTrackStart : EditorTestScene
+    {
+        protected override Ruleset CreateEditorRuleset() => new ManiaRuleset();
+
+        [Test]
+        public void TestPlacement()
+        {
+            AddStep("Seek to 0", () => EditorClock.Seek(0));
+            AddStep("Select note", () => InputManager.Key(Key.Number2));
+            AddStep("Hover negative span", () =>
+            {
+                InputManager.MoveMouseTo(this.ChildrenOfType<Container>().First(x => x.Name == "Icons").Children[0]);
+            });
+            AddStep("Click", () => InputManager.Click(MouseButton.Left));
+            AddAssert("No notes placed", () => EditorBeatmap.HitObjects.All(x => x.StartTime >= 0));
+        }
+    }
+}

osu.Game.Rulesets.Mania/Configuration/ManiaRulesetConfigManager.cs

@@ -4,6 +4,7 @@
 using System;
 using osu.Framework.Configuration.Tracking;
 using osu.Game.Configuration;
+using osu.Game.Localisation;
 using osu.Game.Rulesets.Configuration;
 using osu.Game.Rulesets.Mania.UI;
 
@@ -30,8 +31,8 @@ namespace osu.Game.Rulesets.Mania.Configuration
             new TrackedSetting<double>(ManiaRulesetSetting.ScrollTime,
                 scrollTime => new SettingDescription(
                     rawValue: scrollTime,
-                    name: "Scroll Speed",
+                    name: RulesetSettingsStrings.ScrollSpeed,
-                    value: $"{scrollTime}ms (speed {(int)Math.Round(DrawableManiaRuleset.MAX_TIME_RANGE / scrollTime)})"
+                    value: RulesetSettingsStrings.ScrollSpeedTooltip(scrollTime, (int)Math.Round(DrawableManiaRuleset.MAX_TIME_RANGE / scrollTime))
                 )
             )
         };

osu.Game.Rulesets.Mania/ManiaSettingsSubsection.cs

@@ -6,6 +6,7 @@ using osu.Framework.Allocation;
 using osu.Framework.Graphics;
 using osu.Framework.Localisation;
 using osu.Game.Graphics.UserInterface;
+using osu.Game.Localisation;
 using osu.Game.Overlays.Settings;
 using osu.Game.Rulesets.Mania.Configuration;
 using osu.Game.Rulesets.Mania.UI;
@@ -30,18 +31,18 @@ namespace osu.Game.Rulesets.Mania
             {
                 new SettingsEnumDropdown<ManiaScrollingDirection>
                 {
-                    LabelText = "Scrolling direction",
+                    LabelText = RulesetSettingsStrings.ScrollingDirection,
                     Current = config.GetBindable<ManiaScrollingDirection>(ManiaRulesetSetting.ScrollDirection)
                 },
                 new SettingsSlider<double, ManiaScrollSlider>
                 {
-                    LabelText = "Scroll speed",
+                    LabelText = RulesetSettingsStrings.ScrollSpeed,
                     Current = config.GetBindable<double>(ManiaRulesetSetting.ScrollTime),
                     KeyboardStep = 5
                 },
                 new SettingsCheckbox
                 {
-                    LabelText = "Timing-based note colouring",
+                    LabelText = RulesetSettingsStrings.TimingBasedColouring,
                     Current = config.GetBindable<bool>(ManiaRulesetSetting.TimingBasedNoteColouring),
                 }
             };
@@ -49,7 +50,7 @@ namespace osu.Game.Rulesets.Mania
 
         private partial class ManiaScrollSlider : OsuSliderBar<double>
         {
-            public override LocalisableString TooltipText => $"{Current.Value}ms (speed {(int)Math.Round(DrawableManiaRuleset.MAX_TIME_RANGE / Current.Value)})";
+            public override LocalisableString TooltipText => RulesetSettingsStrings.ScrollSpeedTooltip(Current.Value, (int)Math.Round(DrawableManiaRuleset.MAX_TIME_RANGE / Current.Value));
         }
     }
 }

osu.Game.Rulesets.Mania/UI/ManiaScrollingDirection.cs

@@ -1,15 +1,18 @@
 // 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.
 
-#nullable disable
+using osu.Framework.Localisation;
-
+using osu.Game.Localisation;
 using osu.Game.Rulesets.UI.Scrolling;
 
 namespace osu.Game.Rulesets.Mania.UI
 {
     public enum ManiaScrollingDirection
     {
+        [LocalisableDescription(typeof(RulesetSettingsStrings), nameof(RulesetSettingsStrings.ScrollingDirectionUp))]
         Up = ScrollingDirection.Up,
+
+        [LocalisableDescription(typeof(RulesetSettingsStrings), nameof(RulesetSettingsStrings.ScrollingDirectionDown))]
         Down = ScrollingDirection.Down
     }
 }

osu.Game.Rulesets.Osu/UI/OsuSettingsSubsection.cs

@@ -1,11 +1,10 @@
 // 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.
 
-#nullable disable
-
 using osu.Framework.Allocation;
 using osu.Framework.Graphics;
 using osu.Framework.Localisation;
+using osu.Game.Localisation;
 using osu.Game.Overlays.Settings;
 using osu.Game.Rulesets.Osu.Configuration;
 using osu.Game.Rulesets.UI;
@@ -30,23 +29,23 @@ namespace osu.Game.Rulesets.Osu.UI
             {
                 new SettingsCheckbox
                 {
-                    LabelText = "Snaking in sliders",
+                    LabelText = RulesetSettingsStrings.SnakingInSliders,
                     Current = config.GetBindable<bool>(OsuRulesetSetting.SnakingInSliders)
                 },
                 new SettingsCheckbox
                 {
                     ClassicDefault = false,
-                    LabelText = "Snaking out sliders",
+                    LabelText = RulesetSettingsStrings.SnakingOutSliders,
                     Current = config.GetBindable<bool>(OsuRulesetSetting.SnakingOutSliders)
                 },
                 new SettingsCheckbox
                 {
-                    LabelText = "Cursor trail",
+                    LabelText = RulesetSettingsStrings.CursorTrail,
                     Current = config.GetBindable<bool>(OsuRulesetSetting.ShowCursorTrail)
                 },
                 new SettingsEnumDropdown<PlayfieldBorderStyle>
                 {
-                    LabelText = "Playfield border style",
+                    LabelText = RulesetSettingsStrings.PlayfieldBorderStyle,
                     Current = config.GetBindable<PlayfieldBorderStyle>(OsuRulesetSetting.PlayfieldBorderStyle),
                 },
             };

osu.Game.Tests/Chat/TestSceneChannelManager.cs

@@ -75,6 +75,8 @@ namespace osu.Game.Tests.Chat
                     return false;
                 };
             });
+
+            AddUntilStep("wait for notifications client", () => channelManager.NotificationsConnected);
         }
 
         [Test]

osu.Game.Tests/Editing/TestSceneSnappingNearZero.cs

@@ -0,0 +1,79 @@
+// 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 NUnit.Framework;
+using osu.Game.Beatmaps.ControlPoints;
+
+namespace osu.Game.Tests.Editing
+{
+    [TestFixture]
+    public class TestSceneSnappingNearZero
+    {
+        private readonly ControlPointInfo cpi = new ControlPointInfo();
+
+        [Test]
+        public void TestOnZero()
+        {
+            test(0, 500, 0, 0);
+            test(0, 500, 100, 0);
+            test(0, 500, 250, 500);
+            test(0, 500, 600, 500);
+
+            test(0, 500, -600, 0);
+        }
+
+        [Test]
+        public void TestAlmostOnZero()
+        {
+            test(50, 500, 0, 50);
+            test(50, 500, 50, 50);
+            test(50, 500, 100, 50);
+            test(50, 500, 299, 50);
+            test(50, 500, 300, 550);
+
+            test(50, 500, -500, 50);
+        }
+
+        [Test]
+        public void TestAlmostOnOne()
+        {
+            test(499, 500, -1, 499);
+            test(499, 500, 0, 499);
+            test(499, 500, 1, 499);
+            test(499, 500, 499, 499);
+            test(499, 500, 600, 499);
+            test(499, 500, 800, 999);
+        }
+
+        [Test]
+        public void TestOnOne()
+        {
+            test(500, 500, -500, 0);
+            test(500, 500, 0, 0);
+            test(500, 500, 200, 0);
+            test(500, 500, 400, 500);
+            test(500, 500, 500, 500);
+            test(500, 500, 600, 500);
+            test(500, 500, 900, 1000);
+        }
+
+        [Test]
+        public void TestNegative()
+        {
+            test(-600, 500, -600, 400);
+            test(-600, 500, -100, 400);
+            test(-600, 500, 0, 400);
+            test(-600, 500, 200, 400);
+            test(-600, 500, 400, 400);
+            test(-600, 500, 600, 400);
+            test(-600, 500, 1000, 900);
+        }
+
+        private void test(double pointTime, double beatLength, double from, double expected)
+        {
+            cpi.Clear();
+            cpi.Add(pointTime, new TimingControlPoint { BeatLength = beatLength });
+            Assert.That(cpi.GetClosestSnappedTime(from, 1), Is.EqualTo(expected), $"From: {from}");
+        }
+    }
+}

osu.Game.Tests/Gameplay/TestSceneMasterGameplayClockContainer.cs

@@ -73,16 +73,6 @@ namespace osu.Game.Tests.Gameplay
         }
 
         [Test]
-        [FlakyTest]
-        /*
-         * Fail rate around 0.15%
-         *
-         * TearDown : osu.Framework.Testing.Drawables.Steps.AssertButton+TracedException : gameplay clock time = 2500
-         * --TearDown
-         *    at osu.Framework.Threading.ScheduledDelegate.RunTaskInternal()
-         *    at osu.Framework.Threading.Scheduler.Update()
-         *    at osu.Framework.Graphics.Drawable.UpdateSubTree()
-         */
         public void TestSeekPerformsInGameplayTime(
             [Values(1.0, 0.5, 2.0)] double clockRate,
             [Values(0.0, 200.0, -200.0)] double userOffset,
@@ -92,6 +82,9 @@ namespace osu.Game.Tests.Gameplay
             ClockBackedTestWorkingBeatmap working = null;
             GameplayClockContainer gameplayClockContainer = null;
 
+            // ReSharper disable once NotAccessedVariable
+            BindableDouble trackAdjustment = null; // keeping a reference for track adjustment
+
             if (setAudioOffsetBeforeConstruction)
                 AddStep($"preset audio offset to {userOffset}", () => localConfig.SetValue(OsuSetting.AudioOffset, userOffset));
 
@@ -103,16 +96,16 @@ namespace osu.Game.Tests.Gameplay
                 gameplayClockContainer.Reset(startClock: !whileStopped);
             });
 
-            AddStep($"set clock rate to {clockRate}", () => working.Track.AddAdjustment(AdjustableProperty.Frequency, new BindableDouble(clockRate)));
+            AddStep($"set clock rate to {clockRate}", () => working.Track.AddAdjustment(AdjustableProperty.Frequency, trackAdjustment = new BindableDouble(clockRate)));
 
             if (!setAudioOffsetBeforeConstruction)
                 AddStep($"set audio offset to {userOffset}", () => localConfig.SetValue(OsuSetting.AudioOffset, userOffset));
 
             AddStep("seek to 2500", () => gameplayClockContainer.Seek(2500));
-            AddStep("gameplay clock time = 2500", () => Assert.AreEqual(gameplayClockContainer.CurrentTime, 2500, 10f));
+            AddAssert("gameplay clock time = 2500", () => gameplayClockContainer.CurrentTime, () => Is.EqualTo(2500).Within(10f));
 
             AddStep("seek to 10000", () => gameplayClockContainer.Seek(10000));
-            AddStep("gameplay clock time = 10000", () => Assert.AreEqual(gameplayClockContainer.CurrentTime, 10000, 10f));
+            AddAssert("gameplay clock time = 10000", () => gameplayClockContainer.CurrentTime, () => Is.EqualTo(10000).Within(10f));
         }
 
         protected override void Dispose(bool isDisposing)

osu.Game.Tests/NonVisual/ClosestBeatDivisorTest.cs

@@ -17,7 +17,7 @@ namespace osu.Game.Tests.NonVisual
         public void TestExactDivisors()
         {
             var cpi = new ControlPointInfo();
-            cpi.Add(-1000, new TimingControlPoint { BeatLength = 1000 });
+            cpi.Add(0, new TimingControlPoint { BeatLength = 1000 });
 
             double[] divisors = { 3, 1, 16, 12, 8, 6, 4, 3, 2, 1 };
 
@@ -47,7 +47,7 @@ namespace osu.Game.Tests.NonVisual
         public void TestExactDivisorsHighBPMStream()
         {
             var cpi = new ControlPointInfo();
-            cpi.Add(-50, new TimingControlPoint { BeatLength = 50 }); // 1200 BPM 1/4 (limit testing)
+            cpi.Add(0, new TimingControlPoint { BeatLength = 50 }); // 1200 BPM 1/4 (limit testing)
 
             // A 1/4 stream should land on 1/1, 1/2 and 1/4 divisors.
             double[] divisors = { 4, 4, 4, 4, 4, 4, 4, 4 };
@@ -60,7 +60,7 @@ namespace osu.Game.Tests.NonVisual
         public void TestApproximateDivisors()
         {
             var cpi = new ControlPointInfo();
-            cpi.Add(-1000, new TimingControlPoint { BeatLength = 1000 });
+            cpi.Add(0, new TimingControlPoint { BeatLength = 1000 });
 
             double[] divisors = { 3.03d, 0.97d, 14, 13, 7.94d, 6.08d, 3.93d, 2.96d, 2.02d, 64 };
             double[] closestDivisors = { 3, 1, 16, 12, 8, 6, 4, 3, 2, 1 };
@@ -68,7 +68,7 @@ namespace osu.Game.Tests.NonVisual
             assertClosestDivisors(divisors, closestDivisors, cpi);
         }
 
-        private void assertClosestDivisors(IReadOnlyList<double> divisors, IReadOnlyList<double> closestDivisors, ControlPointInfo cpi, double step = 1)
+        private static void assertClosestDivisors(IReadOnlyList<double> divisors, IReadOnlyList<double> closestDivisors, ControlPointInfo cpi, double step = 1)
         {
             List<HitObject> hitobjects = new List<HitObject>();
             double offset = cpi.TimingPoints[0].Time;

osu.Game.Tests/Resources/TestResources.cs

@@ -12,6 +12,7 @@ using System.Threading;
 using NUnit.Framework;
 using osu.Framework.Extensions;
 using osu.Framework.IO.Stores;
+using osu.Framework.Logging;
 using osu.Framework.Testing;
 using osu.Framework.Utils;
 using osu.Game.Beatmaps;
@@ -93,10 +94,12 @@ namespace osu.Game.Tests.Resources
             {
                 // Create random metadata, then we can check if sorting works based on these
                 Artist = "Some Artist " + RNG.Next(0, 9),
-                Title = $"Some Song (set id {setId}) {Guid.NewGuid()}",
+                Title = $"Some Song (set id {setId:000}) {Guid.NewGuid()}",
                 Author = { Username = "Some Guy " + RNG.Next(0, 9) },
             };
 
+            Logger.Log($"🛠️ Generating beatmap set \"{metadata}\" for test consumption.");
+
             var beatmapSet = new BeatmapSetInfo
             {
                 OnlineID = setId,

osu.Game.Tests/Visual/Editing/TestSceneEditorBeatmapCreation.cs

@@ -20,6 +20,8 @@ using osu.Game.Rulesets.Catch;
 using osu.Game.Rulesets.Osu;
 using osu.Game.Rulesets.Osu.Objects;
 using osu.Game.Rulesets.Osu.UI;
+using osu.Game.Rulesets.Taiko;
+using osu.Game.Rulesets.Taiko.Objects;
 using osu.Game.Screens.Edit;
 using osu.Game.Screens.Edit.Setup;
 using osu.Game.Storyboards;
@@ -395,5 +397,52 @@ namespace osu.Game.Tests.Visual.Editing
                 return set != null && set.PerformRead(s => s.Beatmaps.Count == 2 && s.Files.Count == 2);
             });
         }
+
+        [Test]
+        public void TestCreateNewDifficultyForInconvertibleRuleset()
+        {
+            Guid setId = Guid.Empty;
+
+            AddStep("retrieve set ID", () => setId = EditorBeatmap.BeatmapInfo.BeatmapSet!.ID);
+            AddStep("save beatmap", () => Editor.Save());
+            AddStep("try to create new taiko difficulty", () => Editor.CreateNewDifficulty(new TaikoRuleset().RulesetInfo));
+
+            AddUntilStep("wait for created", () =>
+            {
+                string? difficultyName = Editor.ChildrenOfType<EditorBeatmap>().SingleOrDefault()?.BeatmapInfo.DifficultyName;
+                return difficultyName != null && difficultyName == "New Difficulty";
+            });
+            AddAssert("new difficulty persisted", () =>
+            {
+                var set = beatmapManager.QueryBeatmapSet(s => s.ID == setId);
+                return set != null && set.PerformRead(s => s.Beatmaps.Count == 2 && s.Files.Count == 2);
+            });
+
+            AddStep("add timing point", () => EditorBeatmap.ControlPointInfo.Add(0, new TimingControlPoint { BeatLength = 1000 }));
+            AddStep("add hitobjects", () => EditorBeatmap.AddRange(new[]
+            {
+                new Hit
+                {
+                    StartTime = 0
+                },
+                new Hit
+                {
+                    StartTime = 1000
+                }
+            }));
+            AddStep("save beatmap", () => Editor.Save());
+            AddStep("try to create new catch difficulty", () => Editor.CreateNewDifficulty(new CatchRuleset().RulesetInfo));
+
+            AddUntilStep("wait for created", () =>
+            {
+                string? difficultyName = Editor.ChildrenOfType<EditorBeatmap>().SingleOrDefault()?.BeatmapInfo.DifficultyName;
+                return difficultyName != null && difficultyName == "New Difficulty (1)";
+            });
+            AddAssert("new difficulty persisted", () =>
+            {
+                var set = beatmapManager.QueryBeatmapSet(s => s.ID == setId);
+                return set != null && set.PerformRead(s => s.Beatmaps.Count == 3 && s.Files.Count == 3);
+            });
+        }
     }
 }

osu.Game.Tests/Visual/Editing/TestSceneEditorSaving.cs

@@ -144,7 +144,7 @@ namespace osu.Game.Tests.Visual.Editing
             double lastStarRating = 0;
             double lastLength = 0;
 
-            AddStep("Add timing point", () => EditorBeatmap.ControlPointInfo.Add(500, new TimingControlPoint()));
+            AddStep("Add timing point", () => EditorBeatmap.ControlPointInfo.Add(200, new TimingControlPoint { BeatLength = 600 }));
             AddStep("Change to placement mode", () => InputManager.Key(Key.Number2));
             AddStep("Move to playfield", () => InputManager.MoveMouseTo(Game.ScreenSpaceDrawQuad.Centre));
             AddStep("Place single hitcircle", () => InputManager.Click(MouseButton.Left));

osu.Game.Tests/Visual/Gameplay/TestScenePlayerScoreSubmission.cs

@@ -181,7 +181,8 @@ namespace osu.Game.Tests.Visual.Gameplay
             AddUntilStep("wait for fail", () => Player.GameplayState.HasFailed);
             AddStep("exit", () => Player.Exit());
 
-            AddAssert("ensure failing submission", () => Player.SubmittedScore?.ScoreInfo.Passed == false);
+            AddUntilStep("wait for submission", () => Player.SubmittedScore != null);
+            AddAssert("ensure failing submission", () => Player.SubmittedScore.ScoreInfo.Passed == false);
         }
 
         [Test]
@@ -209,7 +210,9 @@ namespace osu.Game.Tests.Visual.Gameplay
             addFakeHit();
 
             AddStep("exit", () => Player.Exit());
-            AddAssert("ensure failing submission", () => Player.SubmittedScore?.ScoreInfo.Passed == false);
+
+            AddUntilStep("wait for submission", () => Player.SubmittedScore != null);
+            AddAssert("ensure failing submission", () => Player.SubmittedScore.ScoreInfo.Passed == false);
         }
 
         [Test]

osu.Game.Tests/Visual/Multiplayer/TestSceneAllPlayersQueueMode.cs

@@ -34,6 +34,24 @@ namespace osu.Game.Tests.Visual.Multiplayer
         }
 
         [Test]
+        public void TestSingleItemExpiredAfterGameplay()
+        {
+            RunGameplay();
+
+            AddUntilStep("playlist has only one item", () => MultiplayerClient.ClientAPIRoom?.Playlist.Count == 1);
+            AddUntilStep("playlist item is expired", () => MultiplayerClient.ClientAPIRoom?.Playlist[0].Expired == true);
+            AddUntilStep("last item selected", () => MultiplayerClient.ClientRoom?.Settings.PlaylistItemId == MultiplayerClient.ClientAPIRoom?.Playlist[0].ID);
+        }
+
+        [Test]
+        [FlakyTest]
+        /*
+         * TearDown : System.TimeoutException : "wait for ongoing operation to complete" timed out
+         *   --TearDown
+         *      at osu.Framework.Testing.Drawables.Steps.UntilStepButton.<>c__DisplayClass11_0.<.ctor>b__0()
+         *      at osu.Framework.Testing.Drawables.Steps.StepButton.PerformStep(Boolean userTriggered)
+         *      at osu.Framework.Testing.TestScene.runNextStep(Action onCompletion, Action`1 onError, Func`2 stopCondition)
+         */
         public void TestItemAddedToTheEndOfQueue()
         {
             addItem(() => OtherBeatmap);
@@ -46,16 +64,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
         }
 
         [Test]
-        public void TestSingleItemExpiredAfterGameplay()
+        [FlakyTest] // See above
-        {
-            RunGameplay();
-
-            AddUntilStep("playlist has only one item", () => MultiplayerClient.ClientAPIRoom?.Playlist.Count == 1);
-            AddUntilStep("playlist item is expired", () => MultiplayerClient.ClientAPIRoom?.Playlist[0].Expired == true);
-            AddUntilStep("last item selected", () => MultiplayerClient.ClientRoom?.Settings.PlaylistItemId == MultiplayerClient.ClientAPIRoom?.Playlist[0].ID);
-        }
-
-        [Test]
         public void TestNextItemSelectedAfterGameplayFinish()
         {
             addItem(() => OtherBeatmap);
@@ -73,6 +82,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
         }
 
         [Test]
+        [FlakyTest] // See above
         public void TestItemsNotClearedWhenSwitchToHostOnlyMode()
         {
             addItem(() => OtherBeatmap);
@@ -88,6 +98,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
         }
 
         [Test]
+        [FlakyTest] // See above
         public void TestCorrectItemSelectedAfterNewItemAdded()
         {
             addItem(() => OtherBeatmap);
@@ -95,6 +106,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
         }
 
         [Test]
+        [FlakyTest] // See above
         public void TestCorrectRulesetSelectedAfterNewItemAdded()
         {
             addItem(() => OtherBeatmap, new CatchRuleset().RulesetInfo);
@@ -112,6 +124,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
         }
 
         [Test]
+        [FlakyTest] // See above
         public void TestCorrectModsSelectedAfterNewItemAdded()
         {
             addItem(() => OtherBeatmap, mods: new Mod[] { new OsuModDoubleTime() });

osu.Game.Tests/Visual/Multiplayer/TestSceneHostOnlyQueueMode.cs

@@ -27,22 +27,6 @@ namespace osu.Game.Tests.Visual.Multiplayer
             AddUntilStep("first item selected", () => MultiplayerClient.ClientRoom?.Settings.PlaylistItemId == MultiplayerClient.ClientAPIRoom?.Playlist[0].ID);
         }
 
-        [Test]
-        public void TestItemStillSelectedAfterChangeToSameBeatmap()
-        {
-            selectNewItem(() => InitialBeatmap);
-
-            AddUntilStep("playlist item still selected", () => MultiplayerClient.ClientRoom?.Settings.PlaylistItemId == MultiplayerClient.ClientAPIRoom?.Playlist[0].ID);
-        }
-
-        [Test]
-        public void TestItemStillSelectedAfterChangeToOtherBeatmap()
-        {
-            selectNewItem(() => OtherBeatmap);
-
-            AddUntilStep("playlist item still selected", () => MultiplayerClient.ClientRoom?.Settings.PlaylistItemId == MultiplayerClient.ClientAPIRoom?.Playlist[0].ID);
-        }
-
         [Test]
         public void TestNewItemCreatedAfterGameplayFinished()
         {
@@ -54,20 +38,6 @@ namespace osu.Game.Tests.Visual.Multiplayer
             AddUntilStep("second playlist item selected", () => MultiplayerClient.ClientRoom?.Settings.PlaylistItemId == MultiplayerClient.ClientAPIRoom?.Playlist[1].ID);
         }
 
-        [Test]
-        public void TestOnlyLastItemChangedAfterGameplayFinished()
-        {
-            RunGameplay();
-
-            IBeatmapInfo firstBeatmap = null;
-            AddStep("get first playlist item beatmap", () => firstBeatmap = MultiplayerClient.ServerAPIRoom?.Playlist[0].Beatmap);
-
-            selectNewItem(() => OtherBeatmap);
-
-            AddUntilStep("first playlist item hasn't changed", () => MultiplayerClient.ServerAPIRoom?.Playlist[0].Beatmap == firstBeatmap);
-            AddUntilStep("second playlist item changed", () => MultiplayerClient.ClientAPIRoom?.Playlist[1].Beatmap != firstBeatmap);
-        }
-
         [Test]
         public void TestSettingsUpdatedWhenChangingQueueMode()
         {
@@ -80,6 +50,47 @@ namespace osu.Game.Tests.Visual.Multiplayer
         }
 
         [Test]
+        [FlakyTest]
+        /*
+         * TearDown : System.TimeoutException : "wait for ongoing operation to complete" timed out
+         *   --TearDown
+         *      at osu.Framework.Testing.Drawables.Steps.UntilStepButton.<>c__DisplayClass11_0.<.ctor>b__0()
+         *      at osu.Framework.Testing.Drawables.Steps.StepButton.PerformStep(Boolean userTriggered)
+         *      at osu.Framework.Testing.TestScene.runNextStep(Action onCompletion, Action`1 onError, Func`2 stopCondition)
+         */
+        public void TestItemStillSelectedAfterChangeToSameBeatmap()
+        {
+            selectNewItem(() => InitialBeatmap);
+
+            AddUntilStep("playlist item still selected", () => MultiplayerClient.ClientRoom?.Settings.PlaylistItemId == MultiplayerClient.ClientAPIRoom?.Playlist[0].ID);
+        }
+
+        [Test]
+        [FlakyTest] // See above
+        public void TestItemStillSelectedAfterChangeToOtherBeatmap()
+        {
+            selectNewItem(() => OtherBeatmap);
+
+            AddUntilStep("playlist item still selected", () => MultiplayerClient.ClientRoom?.Settings.PlaylistItemId == MultiplayerClient.ClientAPIRoom?.Playlist[0].ID);
+        }
+
+        [Test]
+        [FlakyTest] // See above
+        public void TestOnlyLastItemChangedAfterGameplayFinished()
+        {
+            RunGameplay();
+
+            IBeatmapInfo firstBeatmap = null;
+            AddStep("get first playlist item beatmap", () => firstBeatmap = MultiplayerClient.ServerAPIRoom?.Playlist[0].Beatmap);
+
+            selectNewItem(() => OtherBeatmap);
+
+            AddUntilStep("first playlist item hasn't changed", () => MultiplayerClient.ServerAPIRoom?.Playlist[0].Beatmap == firstBeatmap);
+            AddUntilStep("second playlist item changed", () => MultiplayerClient.ClientAPIRoom?.Playlist[1].Beatmap != firstBeatmap);
+        }
+
+        [Test]
+        [FlakyTest] // See above
         public void TestAddItemsAsHost()
         {
             addItem(() => OtherBeatmap);

osu.Game.Tests/Visual/Multiplayer/TestSceneMultiplayer.cs

@@ -377,6 +377,17 @@ namespace osu.Game.Tests.Visual.Multiplayer
         }
 
         [Test]
+        [FlakyTest]
+        /*
+         * On a slight investigation, this is occurring due to the ready button
+         * not receiving the click input generated by the manual input manager.
+         *
+         * TearDown : System.TimeoutException : "wait for ready button to be enabled" timed out
+         *   --TearDown
+         *      at osu.Framework.Testing.Drawables.Steps.UntilStepButton.<>c__DisplayClass11_0.<.ctor>b__0()
+         *      at osu.Framework.Testing.Drawables.Steps.StepButton.PerformStep(Boolean userTriggered)
+         *      at osu.Framework.Testing.TestScene.runNextStep(Action onCompletion, Action`1 onError, Func`2 stopCondition)
+         */
         public void TestUserSetToIdleWhenBeatmapDeleted()
         {
             createRoom(() => new Room
@@ -398,6 +409,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
         }
 
         [Test]
+        [FlakyTest] // See above
         public void TestPlayStartsWithCorrectBeatmapWhileAtSongSelect()
         {
             PlaylistItem? item = null;
@@ -438,6 +450,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
         }
 
         [Test]
+        [FlakyTest] // See above
         public void TestPlayStartsWithCorrectRulesetWhileAtSongSelect()
         {
             PlaylistItem? item = null;
@@ -478,6 +491,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
         }
 
         [Test]
+        [FlakyTest] // See above
         public void TestPlayStartsWithCorrectModsWhileAtSongSelect()
         {
             PlaylistItem? item = null;
@@ -651,6 +665,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
         }
 
         [Test]
+        [FlakyTest] // See above
         public void TestGameplayFlow()
         {
             createRoom(() => new Room
@@ -678,6 +693,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
         }
 
         [Test]
+        [FlakyTest] // See above
         public void TestGameplayExitFlow()
         {
             Bindable<double>? holdDelay = null;
@@ -715,6 +731,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
         }
 
         [Test]
+        [FlakyTest] // See above
         public void TestGameplayDoesntStartWithNonLoadedUser()
         {
             createRoom(() => new Room
@@ -796,6 +813,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
         }
 
         [Test]
+        [FlakyTest] // See above
         public void TestSpectatingStateResetOnBackButtonDuringGameplay()
         {
             createRoom(() => new Room
@@ -831,6 +849,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
         }
 
         [Test]
+        [FlakyTest] // See above
         public void TestSpectatingStateNotResetOnBackButtonOutsideOfGameplay()
         {
             createRoom(() => new Room
@@ -869,6 +888,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
         }
 
         [Test]
+        [FlakyTest] // See above
         public void TestItemAddedByOtherUserDuringGameplay()
         {
             createRoom(() => new Room
@@ -899,6 +919,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
         }
 
         [Test]
+        [FlakyTest] // See above
         public void TestItemAddedAndDeletedByOtherUserDuringGameplay()
         {
             createRoom(() => new Room

osu.Game.Tests/Visual/Navigation/TestSceneScreenNavigation.cs

@@ -195,11 +195,17 @@ namespace osu.Game.Tests.Visual.Navigation
             AddUntilStep("wait for player", () =>
             {
                 DismissAnyNotifications();
-                return (player = Game.ScreenStack.CurrentScreen as Player) != null;
+                player = Game.ScreenStack.CurrentScreen as Player;
+                return player?.IsLoaded == true;
             });
 
             AddAssert("retry count is 0", () => player.RestartCount == 0);
 
+            // todo: see https://github.com/ppy/osu/issues/22220
+            // tests are supposed to be immune to this edge case by the logic in TestPlayer,
+            // but we're running a full game instance here, so we have to work around it manually.
+            AddStep("end spectator before retry", () => Game.SpectatorClient.EndPlaying(player.GameplayState));
+
             AddStep("attempt to retry", () => player.ChildrenOfType<HotkeyRetryOverlay>().First().Action());
             AddUntilStep("wait for old player gone", () => Game.ScreenStack.CurrentScreen != player);
 

osu.Game.Tests/Visual/Navigation/TestSceneSkinEditorNavigation.cs

@@ -219,7 +219,7 @@ namespace osu.Game.Tests.Visual.Navigation
 
             AddStep("Click gameplay scene button", () =>
             {
-                InputManager.MoveMouseTo(skinEditor.ChildrenOfType<SkinEditorSceneLibrary.SceneButton>().First(b => b.Text == "Gameplay"));
+                InputManager.MoveMouseTo(skinEditor.ChildrenOfType<SkinEditorSceneLibrary.SceneButton>().First(b => b.Text.ToString() == "Gameplay"));
                 InputManager.Click(MouseButton.Left);
             });
 

osu.Game.Tests/Visual/Navigation/TestSceneStartupBeatmapDisplay.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using System.Linq;
 using NUnit.Framework;
 using osu.Framework.Graphics.Containers;
@@ -50,7 +48,7 @@ namespace osu.Game.Tests.Visual.Navigation
         public void TestBeatmapLink()
         {
             AddUntilStep("Beatmap overlay displayed", () => Game.ChildrenOfType<BeatmapSetOverlay>().FirstOrDefault()?.State.Value == Visibility.Visible);
-            AddUntilStep("Beatmap overlay showing content", () => Game.ChildrenOfType<BeatmapPicker>().FirstOrDefault()?.Beatmap.Value.OnlineID == requested_beatmap_id);
+            AddUntilStep("Beatmap overlay showing content", () => Game.ChildrenOfType<BeatmapPicker>().FirstOrDefault()?.Beatmap.Value?.OnlineID == requested_beatmap_id);
         }
     }
 }

osu.Game.Tests/Visual/Online/TestSceneKudosuHistory.cs

@@ -5,12 +5,12 @@ using osu.Game.Overlays.Profile.Sections.Kudosu;
 using System.Collections.Generic;
 using System;
 using osu.Framework.Graphics.Containers;
-using osu.Game.Graphics;
 using osu.Framework.Allocation;
 using osu.Framework.Graphics.Shapes;
 using osu.Framework.Graphics;
 using osu.Game.Online.API.Requests.Responses;
 using osu.Framework.Extensions.IEnumerableExtensions;
+using osu.Game.Overlays;
 
 namespace osu.Game.Tests.Visual.Online
 {
@@ -18,6 +18,9 @@ namespace osu.Game.Tests.Visual.Online
     {
         private readonly Box background;
 
+        [Cached]
+        private OverlayColourProvider colourProvider = new OverlayColourProvider(OverlayColourScheme.Pink);
+
         public TestSceneKudosuHistory()
         {
             FillFlowContainer<DrawableKudosuHistoryItem> content;
@@ -42,9 +45,9 @@ namespace osu.Game.Tests.Visual.Online
         }
 
         [BackgroundDependencyLoader]
-        private void load(OsuColour colours)
+        private void load()
         {
-            background.Colour = colours.GreySeaFoam;
+            background.Colour = colourProvider.Background4;
         }
 
         private readonly IEnumerable<APIKudosuHistory> items = new[]