Merge branch 'master' into close-playlists

osu.Game.Rulesets.Catch.Tests/Mods/TestSceneCatchModNoScope.cs

@@ -29,7 +29,7 @@ namespace osu.Game.Rulesets.Catch.Tests.Mods
                 },
                 Autoplay = true,
                 PassCondition = () => Player.ScoreProcessor.Combo.Value == 2,
-                Beatmap = new Beatmap
+                CreateBeatmap = () => new Beatmap
                 {
                     HitObjects = new List<HitObject>
                     {
@@ -59,7 +59,7 @@ namespace osu.Game.Rulesets.Catch.Tests.Mods
                 },
                 Autoplay = true,
                 PassCondition = () => true,
-                Beatmap = new Beatmap
+                CreateBeatmap = () => new Beatmap
                 {
                     HitObjects = new List<HitObject>
                     {
@@ -99,7 +99,7 @@ namespace osu.Game.Rulesets.Catch.Tests.Mods
                 },
                 Autoplay = true,
                 PassCondition = () => true,
-                Beatmap = new Beatmap
+                CreateBeatmap = () => new Beatmap
                 {
                     HitObjects = new List<HitObject>
                     {

osu.Game.Rulesets.Catch.Tests/Mods/TestSceneCatchModRelax.cs

@@ -28,7 +28,7 @@ namespace osu.Game.Rulesets.Catch.Tests.Mods
             Mod = new CatchModRelax(),
             Autoplay = false,
             PassCondition = passCondition,
-            Beatmap = new Beatmap
+            CreateBeatmap = () => new Beatmap
             {
                 HitObjects = new List<HitObject>
                 {

osu.Game.Rulesets.Catch.Tests/TestSceneCatchModHidden.cs

@@ -24,7 +24,7 @@ namespace osu.Game.Rulesets.Catch.Tests
         {
             CreateModTest(new ModTestData
             {
-                Beatmap = new Beatmap
+                CreateBeatmap = () => new Beatmap
                 {
                     HitObjects = new List<HitObject>
                     {

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

@@ -10,7 +10,7 @@ namespace osu.Game.Rulesets.Catch.Edit
 {
     public partial class CatchDistanceSnapProvider : ComposerDistanceSnapProvider
     {
-        protected override double ReadCurrentDistanceSnap(HitObject before, HitObject after)
+        public override double ReadCurrentDistanceSnap(HitObject before, HitObject after)
         {
             // osu!catch's distance snap implementation is limited, in that a custom spacing cannot be specified.
             // Therefore this functionality is not currently used.

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

@@ -70,6 +70,8 @@ namespace osu.Game.Rulesets.Catch.Edit
             }));
         }
 
+        protected override Drawable CreateHitObjectInspector() => new CatchHitObjectInspector(DistanceSnapProvider);
+
         protected override IEnumerable<TernaryButton> CreateTernaryButtons()
             => base.CreateTernaryButtons()
                    .Concat(DistanceSnapProvider.CreateTernaryButtons());

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

@@ -0,0 +1,41 @@
+// 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 osu.Game.Rulesets.Catch.Objects;
+using osu.Game.Rulesets.Objects;
+using osu.Game.Screens.Edit.Compose.Components;
+
+namespace osu.Game.Rulesets.Catch.Edit
+{
+    public partial class CatchHitObjectInspector(CatchDistanceSnapProvider snapProvider) : HitObjectInspector
+    {
+        protected override void AddInspectorValues(HitObject[] objects)
+        {
+            base.AddInspectorValues(objects);
+
+            if (objects.Length > 0)
+            {
+                HitObject firstSelectedHitObject = objects.MinBy(ho => ho.StartTime)!;
+                HitObject lastSelectedHitObject = objects.MaxBy(ho => ho.GetEndTime())!;
+
+                HitObject? precedingObject = EditorBeatmap.HitObjects.LastOrDefault(ho => ho.GetEndTime() < firstSelectedHitObject.StartTime);
+                HitObject? nextObject = EditorBeatmap.HitObjects.FirstOrDefault(ho => ho.StartTime > lastSelectedHitObject.GetEndTime());
+
+                if (precedingObject != null && precedingObject is not BananaShower)
+                {
+                    double previousSnap = snapProvider.ReadCurrentDistanceSnap(precedingObject, firstSelectedHitObject);
+                    AddHeader("To previous");
+                    AddValue($"{previousSnap:#,0.##}x");
+                }
+
+                if (nextObject != null && nextObject is not BananaShower)
+                {
+                    double nextSnap = snapProvider.ReadCurrentDistanceSnap(lastSelectedHitObject, nextObject);
+                    AddHeader("To next");
+                    AddValue($"{nextSnap:#,0.##}x");
+                }
+            }
+        }
+    }
+}

osu.Game.Rulesets.Mania.Tests/ManiaScoreProcessorTest.cs

@@ -0,0 +1,39 @@
+// 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.Collections.Generic;
+using NUnit.Framework;
+using osu.Game.Rulesets.Mania.Scoring;
+using osu.Game.Rulesets.Scoring;
+using osu.Game.Scoring;
+
+namespace osu.Game.Rulesets.Mania.Tests
+{
+    [TestFixture]
+    public class ManiaScoreProcessorTest
+    {
+        [TestCase(ScoreRank.X, 1, HitResult.Perfect)]
+        [TestCase(ScoreRank.X, 0.99, HitResult.Great)]
+        [TestCase(ScoreRank.D, 0.1, HitResult.Great)]
+        [TestCase(ScoreRank.X, 0.99, HitResult.Perfect, HitResult.Great)]
+        [TestCase(ScoreRank.X, 0.99, HitResult.Great, HitResult.Great)]
+        [TestCase(ScoreRank.S, 0.99, HitResult.Perfect, HitResult.Good)]
+        [TestCase(ScoreRank.S, 0.99, HitResult.Perfect, HitResult.Ok)]
+        [TestCase(ScoreRank.S, 0.99, HitResult.Perfect, HitResult.Meh)]
+        [TestCase(ScoreRank.S, 0.99, HitResult.Perfect, HitResult.Miss)]
+        [TestCase(ScoreRank.S, 0.99, HitResult.Great, HitResult.Good)]
+        [TestCase(ScoreRank.S, 0.99, HitResult.Great, HitResult.Ok)]
+        [TestCase(ScoreRank.S, 0.99, HitResult.Great, HitResult.Meh)]
+        [TestCase(ScoreRank.S, 0.99, HitResult.Great, HitResult.Miss)]
+        public void TestRanks(ScoreRank expected, double accuracy, params HitResult[] results)
+        {
+            var scoreProcessor = new ManiaScoreProcessor();
+
+            Dictionary<HitResult, int> resultsDict = new Dictionary<HitResult, int>();
+            foreach (var result in results)
+                resultsDict[result] = resultsDict.GetValueOrDefault(result) + 1;
+
+            Assert.That(scoreProcessor.RankFromScore(accuracy, resultsDict), Is.EqualTo(expected));
+        }
+    }
+}

osu.Game.Rulesets.Mania.Tests/Mods/TestSceneManiaModAutoplay.cs

@@ -19,7 +19,7 @@ namespace osu.Game.Rulesets.Mania.Tests.Mods
             CreateModTest(new ModTestData
             {
                 Autoplay = true,
-                Beatmap = new ManiaBeatmap(new StageDefinition(1))
+                CreateBeatmap = () => new ManiaBeatmap(new StageDefinition(1))
                 {
                     HitObjects = new List<ManiaHitObject>
                     {

osu.Game.Rulesets.Mania.Tests/Mods/TestSceneManiaModDoubleTime.cs

@@ -29,7 +29,7 @@ namespace osu.Game.Rulesets.Mania.Tests.Mods
                                   && Precision.AlmostEquals(Player.ScoreProcessor.Accuracy.Value, 0.9836, 0.01)
                                   && Player.ScoreProcessor.TotalScore.Value == 946_049,
             Autoplay = false,
-            Beatmap = new Beatmap
+            CreateBeatmap = () => new Beatmap
             {
                 BeatmapInfo = { Ruleset = new ManiaRuleset().RulesetInfo },
                 Difficulty = { OverallDifficulty = 10 },
@@ -56,7 +56,7 @@ namespace osu.Game.Rulesets.Mania.Tests.Mods
                                       && Player.ScoreProcessor.Accuracy.Value == 1
                                       && Player.ScoreProcessor.TotalScore.Value == (long)(1_000_000 * doubleTime.ScoreMultiplier),
                 Autoplay = false,
-                Beatmap = new Beatmap
+                CreateBeatmap = () => new Beatmap
                 {
                     BeatmapInfo = { Ruleset = new ManiaRuleset().RulesetInfo },
                     Difficulty = { OverallDifficulty = 10 },

osu.Game.Rulesets.Mania.Tests/Mods/TestSceneManiaModFadeIn.cs

@@ -74,7 +74,7 @@ namespace osu.Game.Rulesets.Mania.Tests.Mods
             CreateModTest(new ModTestData
             {
                 Mod = new ManiaModHidden(),
-                Beatmap = new Beatmap
+                CreateBeatmap = () => new Beatmap
                 {
                     HitObjects = Enumerable.Range(1, 100).Select(i => (HitObject)new Note { StartTime = 1000 + 200 * i }).ToList(),
                     Breaks = { new BreakPeriod(2000, 28000) }

osu.Game.Rulesets.Mania.Tests/Mods/TestSceneManiaModHidden.cs

@@ -74,7 +74,7 @@ namespace osu.Game.Rulesets.Mania.Tests.Mods
             CreateModTest(new ModTestData
             {
                 Mod = new ManiaModHidden(),
-                Beatmap = new Beatmap
+                CreateBeatmap = () => new Beatmap
                 {
                     HitObjects = Enumerable.Range(1, 100).Select(i => (HitObject)new Note { StartTime = 1000 + 200 * i }).ToList(),
                     Breaks = { new BreakPeriod(2000, 28000) }

osu.Game.Rulesets.Mania.Tests/Mods/TestSceneManiaModPerfect.cs

@@ -36,7 +36,7 @@ namespace osu.Game.Rulesets.Mania.Tests.Mods
             Mod = new ManiaModPerfect(),
             PassCondition = () => ((ModFailConditionTestPlayer)Player).CheckFailed(false),
             Autoplay = false,
-            Beatmap = new Beatmap
+            CreateBeatmap = () => new Beatmap
             {
                 HitObjects = new List<HitObject>
                 {
@@ -59,7 +59,7 @@ namespace osu.Game.Rulesets.Mania.Tests.Mods
             Mod = new ManiaModPerfect(),
             PassCondition = () => ((ModFailConditionTestPlayer)Player).CheckFailed(true) && Player.Results.Count == 2,
             Autoplay = false,
-            Beatmap = new Beatmap
+            CreateBeatmap = () => new Beatmap
             {
                 HitObjects = new List<HitObject>
                 {

osu.Game.Rulesets.Mania.Tests/Mods/TestSceneManiaModSuddenDeath.cs

@@ -28,7 +28,7 @@ namespace osu.Game.Rulesets.Mania.Tests.Mods
             Mod = new ManiaModSuddenDeath(),
             PassCondition = () => ((ModFailConditionTestPlayer)Player).CheckFailed(false),
             Autoplay = false,
-            Beatmap = new Beatmap
+            CreateBeatmap = () => new Beatmap
             {
                 HitObjects = new List<HitObject>
                 {
@@ -51,7 +51,7 @@ namespace osu.Game.Rulesets.Mania.Tests.Mods
             Mod = new ManiaModSuddenDeath(),
             PassCondition = () => ((ModFailConditionTestPlayer)Player).CheckFailed(true) && Player.Results.Count == 2,
             Autoplay = false,
-            Beatmap = new Beatmap
+            CreateBeatmap = () => new Beatmap
             {
                 HitObjects = new List<HitObject>
                 {

osu.Game.Rulesets.Mania/Scoring/ManiaScoreProcessor.cs

@@ -9,6 +9,7 @@ using osu.Game.Rulesets.Judgements;
 using osu.Game.Rulesets.Mania.Objects;
 using osu.Game.Rulesets.Objects;
 using osu.Game.Rulesets.Scoring;
+using osu.Game.Scoring;
 
 namespace osu.Game.Rulesets.Mania.Scoring
 {
@@ -58,6 +59,24 @@ namespace osu.Game.Rulesets.Mania.Scoring
             return GetBaseScoreForResult(result);
         }
 
+        public override ScoreRank RankFromScore(double accuracy, IReadOnlyDictionary<HitResult, int> results)
+        {
+            ScoreRank rank = base.RankFromScore(accuracy, results);
+
+            if (rank != ScoreRank.S)
+                return rank;
+
+            // SS is expected as long as all hitobjects have been hit with either a GREAT or PERFECT result.
+
+            bool anyImperfect =
+                results.GetValueOrDefault(HitResult.Good) > 0
+                || results.GetValueOrDefault(HitResult.Ok) > 0
+                || results.GetValueOrDefault(HitResult.Meh) > 0
+                || results.GetValueOrDefault(HitResult.Miss) > 0;
+
+            return anyImperfect ? rank : ScoreRank.X;
+        }
+
         private class JudgementOrderComparer : IComparer<HitObject>
         {
             public static readonly JudgementOrderComparer DEFAULT = new JudgementOrderComparer();

osu.Game.Rulesets.Osu.Tests/Mods/TestSceneOsuModAlternate.cs

@@ -23,7 +23,7 @@ namespace osu.Game.Rulesets.Osu.Tests.Mods
             Mod = new OsuModAlternate(),
             PassCondition = () => Player.ScoreProcessor.Combo.Value == 4,
             Autoplay = false,
-            Beatmap = new Beatmap
+            CreateBeatmap = () => new Beatmap
             {
                 HitObjects = new List<HitObject>
                 {
@@ -68,7 +68,7 @@ namespace osu.Game.Rulesets.Osu.Tests.Mods
             Mod = new OsuModAlternate(),
             PassCondition = () => Player.ScoreProcessor.Combo.Value == 0 && Player.ScoreProcessor.HighestCombo.Value == 1,
             Autoplay = false,
-            Beatmap = new Beatmap
+            CreateBeatmap = () => new Beatmap
             {
                 HitObjects = new List<HitObject>
                 {
@@ -101,7 +101,7 @@ namespace osu.Game.Rulesets.Osu.Tests.Mods
             Mod = new OsuModAlternate(),
             PassCondition = () => Player.ScoreProcessor.Combo.Value == 1,
             Autoplay = false,
-            Beatmap = new Beatmap
+            CreateBeatmap = () => new Beatmap
             {
                 HitObjects = new List<HitObject>
                 {
@@ -131,7 +131,7 @@ namespace osu.Game.Rulesets.Osu.Tests.Mods
             Mod = new OsuModAlternate(),
             PassCondition = () => Player.ScoreProcessor.Combo.Value == 0 && Player.ScoreProcessor.HighestCombo.Value == 2,
             Autoplay = false,
-            Beatmap = new Beatmap
+            CreateBeatmap = () => new Beatmap
             {
                 Breaks =
                 {

osu.Game.Rulesets.Osu.Tests/Mods/TestSceneOsuModAutoplay.cs

@@ -60,7 +60,7 @@ namespace osu.Game.Rulesets.Osu.Tests.Mods
             CreateModTest(new ModTestData
             {
                 Autoplay = true,
-                Beatmap = new Beatmap
+                CreateBeatmap = () => new Beatmap
                 {
                     HitObjects = new List<HitObject>
                     {
@@ -90,7 +90,7 @@ namespace osu.Game.Rulesets.Osu.Tests.Mods
             {
                 Autoplay = true,
                 Mod = mod,
-                Beatmap = new Beatmap
+                CreateBeatmap = () => new Beatmap
                 {
                     HitObjects =
                     {

osu.Game.Rulesets.Osu.Tests/Mods/TestSceneOsuModDifficultyAdjust.cs

@@ -21,7 +21,7 @@ namespace osu.Game.Rulesets.Osu.Tests.Mods
         public void TestNoAdjustment() => CreateModTest(new ModTestData
         {
             Mod = new OsuModDifficultyAdjust(),
-            Beatmap = new Beatmap
+            CreateBeatmap = () => new Beatmap
             {
                 BeatmapInfo = new BeatmapInfo
                 {

osu.Game.Rulesets.Osu.Tests/Mods/TestSceneOsuModFlashlight.cs

@@ -68,7 +68,7 @@ namespace osu.Game.Rulesets.Osu.Tests.Mods
                         Player.GameplayClockContainer.CurrentTime < 1000 && Player.ChildrenOfType<ModFlashlight<OsuHitObject>.Flashlight>().Single().FlashlightDim > 0;
                     return Player.GameplayState.HasPassed && !sliderDimmedBeforeStartTime;
                 },
-                Beatmap = new OsuBeatmap
+                CreateBeatmap = () => new OsuBeatmap
                 {
                     HitObjects = new List<OsuHitObject>
                     {
@@ -114,7 +114,7 @@ namespace osu.Game.Rulesets.Osu.Tests.Mods
                         Player.GameplayClockContainer.CurrentTime >= 1000 && Player.ChildrenOfType<ModFlashlight<OsuHitObject>.Flashlight>().Single().FlashlightDim > 0;
                     return Player.GameplayState.HasPassed && sliderDimmed;
                 },
-                Beatmap = new OsuBeatmap
+                CreateBeatmap = () => new OsuBeatmap
                 {
                     HitObjects = new List<OsuHitObject>
                     {
@@ -153,7 +153,7 @@ namespace osu.Game.Rulesets.Osu.Tests.Mods
                         Player.GameplayClockContainer.CurrentTime >= 1000 && Player.ChildrenOfType<ModFlashlight<OsuHitObject>.Flashlight>().Single().FlashlightDim > 0;
                     return Player.GameplayState.HasPassed && sliderDimmed;
                 },
-                Beatmap = new OsuBeatmap
+                CreateBeatmap = () => new OsuBeatmap
                 {
                     HitObjects = new List<OsuHitObject>
                     {

osu.Game.Rulesets.Osu.Tests/Mods/TestSceneOsuModHidden.cs

@@ -28,7 +28,7 @@ namespace osu.Game.Rulesets.Osu.Tests.Mods
         {
             Mod = new TestOsuModHidden(),
             Autoplay = true,
-            Beatmap = new Beatmap
+            CreateBeatmap = () => new Beatmap
             {
                 HitObjects = new List<HitObject>
                 {
@@ -63,7 +63,7 @@ namespace osu.Game.Rulesets.Osu.Tests.Mods
         {
             Mod = new TestOsuModHidden(),
             Autoplay = true,
-            Beatmap = new Beatmap
+            CreateBeatmap = () => new Beatmap
             {
                 HitObjects = new List<HitObject>
                 {
@@ -98,7 +98,7 @@ namespace osu.Game.Rulesets.Osu.Tests.Mods
         {
             Mod = new TestOsuModHidden(),
             Autoplay = true,
-            Beatmap = new Beatmap
+            CreateBeatmap = () => new Beatmap
             {
                 HitObjects = new List<HitObject>
                 {
@@ -122,7 +122,7 @@ namespace osu.Game.Rulesets.Osu.Tests.Mods
         {
             Mod = new OsuModHidden { OnlyFadeApproachCircles = { Value = true } },
             Autoplay = true,
-            Beatmap = new Beatmap
+            CreateBeatmap = () => new Beatmap
             {
                 HitObjects = new List<HitObject>
                 {

osu.Game.Rulesets.Osu.Tests/Mods/TestSceneOsuModMirror.cs

@@ -21,7 +21,7 @@ namespace osu.Game.Rulesets.Osu.Tests.Mods
         public void TestCorrectReflections([Values] OsuModMirror.MirrorType type, [Values] bool withStrictTracking) => CreateModTest(new ModTestData
         {
             Autoplay = true,
-            Beatmap = new OsuBeatmap
+            CreateBeatmap = () => new OsuBeatmap
             {
                 HitObjects =
                 {

osu.Game.Rulesets.Osu.Tests/Mods/TestSceneOsuModNoScope.cs

@@ -31,7 +31,7 @@ namespace osu.Game.Rulesets.Osu.Tests.Mods
                 },
                 Autoplay = true,
                 PassCondition = () => true,
-                Beatmap = new Beatmap
+                CreateBeatmap = () => new Beatmap
                 {
                     HitObjects = new List<HitObject>
                     {
@@ -71,7 +71,7 @@ namespace osu.Game.Rulesets.Osu.Tests.Mods
                 },
                 Autoplay = true,
                 PassCondition = () => true,
-                Beatmap = new Beatmap
+                CreateBeatmap = () => new Beatmap
                 {
                     HitObjects = new List<HitObject>
                     {
@@ -113,7 +113,7 @@ namespace osu.Game.Rulesets.Osu.Tests.Mods
                 },
                 Autoplay = true,
                 PassCondition = () => true,
-                Beatmap = new Beatmap
+                CreateBeatmap = () => new Beatmap
                 {
                     HitObjects = new List<HitObject>
                     {

osu.Game.Rulesets.Osu.Tests/Mods/TestSceneOsuModPerfect.cs

@@ -61,7 +61,7 @@ namespace osu.Game.Rulesets.Osu.Tests.Mods
             Mod = new OsuModPerfect(),
             PassCondition = () => ((ModFailConditionTestPlayer)Player).CheckFailed(true),
             Autoplay = false,
-            Beatmap = new Beatmap
+            CreateBeatmap = () => new Beatmap
             {
                 HitObjects = new List<HitObject>
                 {

osu.Game.Rulesets.Osu.Tests/Mods/TestSceneOsuModRandom.cs

@@ -36,7 +36,7 @@ namespace osu.Game.Rulesets.Osu.Tests.Mods
             {
                 AngleSharpness = { Value = angleSharpness }
             },
-            Beatmap = jumpBeatmap,
+            CreateBeatmap = jumpBeatmap,
             Autoplay = true,
             PassCondition = () => true
         });
@@ -50,15 +50,15 @@ namespace osu.Game.Rulesets.Osu.Tests.Mods
             {
                 AngleSharpness = { Value = angleSharpness }
             },
-            Beatmap = streamBeatmap,
+            CreateBeatmap = streamBeatmap,
             Autoplay = true,
             PassCondition = () => true
         });
 
-        private OsuBeatmap jumpBeatmap =>
+        private OsuBeatmap jumpBeatmap() =>
             createHitCircleBeatmap(new[] { 100, 200, 300, 400 }, 8, 300, 2 * 300);
 
-        private OsuBeatmap streamBeatmap =>
+        private OsuBeatmap streamBeatmap() =>
             createHitCircleBeatmap(new[] { 10, 20, 30, 40, 50, 60, 70, 80 }, 16, 150, 4 * 150);
 
         private OsuBeatmap createHitCircleBeatmap(IEnumerable<int> spacings, int objectsPerSpacing, int interval, int beatLength)

osu.Game.Rulesets.Osu.Tests/Mods/TestSceneOsuModSingleTap.cs

@@ -22,7 +22,7 @@ namespace osu.Game.Rulesets.Osu.Tests.Mods
             Mod = new OsuModSingleTap(),
             PassCondition = () => Player.ScoreProcessor.Combo.Value == 2,
             Autoplay = false,
-            Beatmap = new Beatmap
+            CreateBeatmap = () => new Beatmap
             {
                 HitObjects = new List<HitObject>
                 {
@@ -62,7 +62,7 @@ namespace osu.Game.Rulesets.Osu.Tests.Mods
             Mod = new OsuModSingleTap(),
             PassCondition = () => Player.ScoreProcessor.Combo.Value == 0 && Player.ScoreProcessor.HighestCombo.Value == 1,
             Autoplay = false,
-            Beatmap = new Beatmap
+            CreateBeatmap = () => new Beatmap
             {
                 HitObjects = new List<HitObject>
                 {
@@ -100,7 +100,7 @@ namespace osu.Game.Rulesets.Osu.Tests.Mods
             Mod = new OsuModSingleTap(),
             PassCondition = () => Player.ScoreProcessor.Combo.Value == 1,
             Autoplay = false,
-            Beatmap = new Beatmap
+            CreateBeatmap = () => new Beatmap
             {
                 HitObjects = new List<HitObject>
                 {
@@ -130,7 +130,7 @@ namespace osu.Game.Rulesets.Osu.Tests.Mods
             Mod = new OsuModSingleTap(),
             PassCondition = () => Player.ScoreProcessor.Combo.Value == 0 && Player.ScoreProcessor.HighestCombo.Value == 2,
             Autoplay = false,
-            Beatmap = new Beatmap
+            CreateBeatmap = () => new Beatmap
             {
                 Breaks =
                 {

osu.Game.Rulesets.Osu.Tests/Mods/TestSceneOsuModSpunOut.cs

@@ -35,7 +35,7 @@ namespace osu.Game.Rulesets.Osu.Tests.Mods
             {
                 Mod = new OsuModSpunOut(),
                 Autoplay = false,
-                Beatmap = singleSpinnerBeatmap,
+                CreateBeatmap = singleSpinnerBeatmap,
                 PassCondition = () =>
                 {
                     // Bind to the first spinner's results for further tracking.
@@ -71,7 +71,7 @@ namespace osu.Game.Rulesets.Osu.Tests.Mods
             {
                 Mods = mods,
                 Autoplay = false,
-                Beatmap = singleSpinnerBeatmap,
+                CreateBeatmap = singleSpinnerBeatmap,
                 PassCondition = () =>
                 {
                     var counter = Player.ChildrenOfType<SpinnerSpmCalculator>().SingleOrDefault();
@@ -101,7 +101,7 @@ namespace osu.Game.Rulesets.Osu.Tests.Mods
             {
                 Mod = new OsuModSpunOut(),
                 Autoplay = false,
-                Beatmap = singleSpinnerBeatmap,
+                CreateBeatmap = singleSpinnerBeatmap,
                 PassCondition = () =>
                 {
                     // Bind to the first spinner's results for further tracking.
@@ -130,7 +130,7 @@ namespace osu.Game.Rulesets.Osu.Tests.Mods
             });
         }
 
-        private Beatmap singleSpinnerBeatmap => new Beatmap
+        private Beatmap singleSpinnerBeatmap() => new Beatmap
         {
             HitObjects = new List<HitObject>
             {

osu.Game.Rulesets.Osu.Tests/Mods/TestSceneOsuModStrictTracking.cs

@@ -20,7 +20,7 @@ namespace osu.Game.Rulesets.Osu.Tests.Mods
         {
             Mod = new OsuModStrictTracking(),
             Autoplay = false,
-            Beatmap = new Beatmap
+            CreateBeatmap = () => new Beatmap
             {
                 HitObjects = new List<HitObject>
                 {

osu.Game.Rulesets.Osu.Tests/Mods/TestSceneOsuModSuddenDeath.cs

@@ -30,7 +30,7 @@ namespace osu.Game.Rulesets.Osu.Tests.Mods
             Mod = new OsuModSuddenDeath(),
             PassCondition = () => ((ModFailConditionTestPlayer)Player).CheckFailed(false),
             Autoplay = false,
-            Beatmap = new Beatmap
+            CreateBeatmap = () => new Beatmap
             {
                 HitObjects = new List<HitObject>
                 {
@@ -55,7 +55,7 @@ namespace osu.Game.Rulesets.Osu.Tests.Mods
             Mod = new OsuModSuddenDeath(),
             PassCondition = () => ((ModFailConditionTestPlayer)Player).CheckFailed(true),
             Autoplay = false,
-            Beatmap = new Beatmap
+            CreateBeatmap = () => new Beatmap
             {
                 HitObjects = new List<HitObject>
                 {

osu.Game.Rulesets.Osu.Tests/TestSceneMissHitWindowJudgements.cs

@@ -36,7 +36,7 @@ namespace osu.Game.Rulesets.Osu.Tests
             {
                 Autoplay = false,
                 Mod = new TestAutoMod(),
-                Beatmap = new Beatmap
+                CreateBeatmap = () => new Beatmap
                 {
                     HitObjects = { new HitCircle { Position = new Vector2(256, 192) } }
                 },
@@ -47,18 +47,16 @@ namespace osu.Game.Rulesets.Osu.Tests
         [Test]
         public void TestMissViaNotHitting()
         {
-            var beatmap = new Beatmap
-            {
-                HitObjects = { new HitCircle { Position = new Vector2(256, 192) } }
-            };
-
             var hitWindows = new OsuHitWindows();
-            hitWindows.SetDifficulty(beatmap.Difficulty.OverallDifficulty);
+            hitWindows.SetDifficulty(IBeatmapDifficultyInfo.DEFAULT_DIFFICULTY);
 
             CreateModTest(new ModTestData
             {
                 Autoplay = false,
-                Beatmap = beatmap,
+                CreateBeatmap = () => new Beatmap
+                {
+                    HitObjects = { new HitCircle { Position = new Vector2(256, 192) } }
+                },
                 PassCondition = () => Player.Results.Count > 0 && Player.Results[0].TimeOffset >= hitWindows.WindowFor(HitResult.Meh) && !Player.Results[0].IsHit
             });
         }

osu.Game.Rulesets.Osu/Edit/OsuDistanceSnapProvider.cs

@@ -12,7 +12,7 @@ namespace osu.Game.Rulesets.Osu.Edit
 {
     public partial class OsuDistanceSnapProvider : ComposerDistanceSnapProvider
     {
-        protected override double ReadCurrentDistanceSnap(HitObject before, HitObject after)
+        public override double ReadCurrentDistanceSnap(HitObject before, HitObject after)
         {
             float expectedDistance = DurationToDistance(before, after.StartTime - before.GetEndTime());
             float actualDistance = Vector2.Distance(((OsuHitObject)before).EndPosition, ((OsuHitObject)after).Position);

osu.Game.Rulesets.Taiko.Tests/Mods/TestSceneTaikoModHidden.cs

@@ -31,6 +31,13 @@ namespace osu.Game.Rulesets.Taiko.Tests.Mods
         {
             const double hit_time = 1;
 
+            CreateModTest(new ModTestData
+            {
+                Mod = new TaikoModHidden(),
+                Autoplay = true,
+                PassCondition = checkAllMaxResultJudgements(2),
+                CreateBeatmap = () =>
+                {
                     var beatmap = new Beatmap<TaikoHitObject>
                     {
                         HitObjects = new List<TaikoHitObject>
@@ -58,13 +65,8 @@ namespace osu.Game.Rulesets.Taiko.Tests.Mods
                     };
 
                     beatmap.ControlPointInfo.Add(0, new EffectControlPoint { ScrollSpeed = 0.1f });
-
+                    return beatmap;
-            CreateModTest(new ModTestData
+                },
-            {
-                Mod = new TaikoModHidden(),
-                Autoplay = true,
-                PassCondition = checkAllMaxResultJudgements(2),
-                Beatmap = beatmap,
             });
         }
     }

osu.Game.Rulesets.Taiko.Tests/Mods/TestSceneTaikoModRelax.cs

@@ -15,7 +15,26 @@ namespace osu.Game.Rulesets.Taiko.Tests.Mods
         [Test]
         public void TestRelax()
         {
-            var beatmap = new TaikoBeatmap
+            var beatmapForReplay = createBeatmap();
+
+            foreach (var ho in beatmapForReplay.HitObjects)
+                ho.ApplyDefaults(beatmapForReplay.ControlPointInfo, beatmapForReplay.Difficulty);
+
+            var replay = new TaikoAutoGenerator(beatmapForReplay).Generate();
+
+            foreach (var frame in replay.Frames.OfType<TaikoReplayFrame>().Where(r => r.Actions.Any()))
+                frame.Actions = [TaikoAction.LeftCentre];
+
+            CreateModTest(new ModTestData
+            {
+                Mod = new TaikoModRelax(),
+                CreateBeatmap = createBeatmap,
+                ReplayFrames = replay.Frames,
+                Autoplay = false,
+                PassCondition = () => Player.ScoreProcessor.HasCompleted.Value && Player.ScoreProcessor.Accuracy.Value == 1,
+            });
+
+            TaikoBeatmap createBeatmap() => new TaikoBeatmap
             {
                 HitObjects =
                 {
@@ -25,22 +44,6 @@ namespace osu.Game.Rulesets.Taiko.Tests.Mods
                     new Swell { StartTime = 1250, Duration = 500 },
                 }
             };
-            foreach (var ho in beatmap.HitObjects)
-                ho.ApplyDefaults(beatmap.ControlPointInfo, beatmap.Difficulty);
-
-            var replay = new TaikoAutoGenerator(beatmap).Generate();
-
-            foreach (var frame in replay.Frames.OfType<TaikoReplayFrame>().Where(r => r.Actions.Any()))
-                frame.Actions = [TaikoAction.LeftCentre];
-
-            CreateModTest(new ModTestData
-            {
-                Mod = new TaikoModRelax(),
-                Beatmap = beatmap,
-                ReplayFrames = replay.Frames,
-                Autoplay = false,
-                PassCondition = () => Player.ScoreProcessor.HasCompleted.Value && Player.ScoreProcessor.Accuracy.Value == 1,
-            });
         }
     }
 }

osu.Game.Rulesets.Taiko.Tests/Mods/TestSceneTaikoModSingleTap.cs

@@ -20,7 +20,7 @@ namespace osu.Game.Rulesets.Taiko.Tests.Mods
         {
             Mod = new TaikoModSingleTap(),
             Autoplay = false,
-            Beatmap = new Beatmap
+            CreateBeatmap = () => new Beatmap
             {
                 HitObjects = new List<HitObject>
                 {
@@ -65,7 +65,7 @@ namespace osu.Game.Rulesets.Taiko.Tests.Mods
         {
             Mod = new TaikoModSingleTap(),
             Autoplay = false,
-            Beatmap = new Beatmap
+            CreateBeatmap = () => new Beatmap
             {
                 HitObjects = new List<HitObject>
                 {
@@ -110,7 +110,7 @@ namespace osu.Game.Rulesets.Taiko.Tests.Mods
         {
             Mod = new TaikoModSingleTap(),
             Autoplay = false,
-            Beatmap = new Beatmap
+            CreateBeatmap = () => new Beatmap
             {
                 HitObjects = new List<HitObject>
                 {
@@ -136,7 +136,7 @@ namespace osu.Game.Rulesets.Taiko.Tests.Mods
         {
             Mod = new TaikoModSingleTap(),
             Autoplay = false,
-            Beatmap = new Beatmap
+            CreateBeatmap = () => new Beatmap
             {
                 HitObjects = new List<HitObject>
                 {
@@ -175,7 +175,7 @@ namespace osu.Game.Rulesets.Taiko.Tests.Mods
         {
             Mod = new TaikoModSingleTap(),
             Autoplay = false,
-            Beatmap = new Beatmap
+            CreateBeatmap = () => new Beatmap
             {
                 Breaks =
                 {

osu.Game.Tests/Beatmaps/IO/LegacyBeatmapExporterTest.cs

@@ -2,6 +2,7 @@
 // See the LICENCE file in the repository root for full licence text.
 
 using System.IO;
+using System.Text;
 using NUnit.Framework;
 using osu.Framework.Allocation;
 using osu.Framework.Extensions;
@@ -9,6 +10,7 @@ using osu.Framework.Extensions.ObjectExtensions;
 using osu.Framework.Testing;
 using osu.Game.Beatmaps;
 using osu.Game.Database;
+using osu.Game.IO.Archives;
 using osu.Game.Tests.Resources;
 using osu.Game.Tests.Visual;
 using MemoryStream = System.IO.MemoryStream;
@@ -48,6 +50,47 @@ namespace osu.Game.Tests.Beatmaps.IO
             AddAssert("hit object is snapped", () => beatmap.Beatmap.HitObjects[0].StartTime, () => Is.EqualTo(28519).Within(0.001));
         }
 
+        [Test]
+        public void TestExportStability()
+        {
+            IWorkingBeatmap beatmap = null!;
+            MemoryStream firstExport = null!;
+            MemoryStream secondExport = null!;
+
+            // Ensure importer encoding is correct
+            AddStep("import beatmap", () => beatmap = importBeatmapFromArchives(@"legacy-export-stability-test.olz"));
+            AddStep("export once", () =>
+            {
+                firstExport = new MemoryStream();
+
+                new LegacyBeatmapExporter(LocalStorage)
+                    .ExportToStream((BeatmapSetInfo)beatmap.BeatmapInfo.BeatmapSet!, firstExport, null);
+            });
+
+            AddStep("import beatmap again", () => beatmap = importBeatmapFromStream(firstExport));
+            AddStep("export again", () =>
+            {
+                secondExport = new MemoryStream();
+
+                new LegacyBeatmapExporter(LocalStorage)
+                    .ExportToStream((BeatmapSetInfo)beatmap.BeatmapInfo.BeatmapSet!, secondExport, null);
+            });
+
+            const string osu_filename = @"legacy export - stability test (spaceman_atlas) [].osu";
+
+            AddAssert("exports are identical",
+                () => getStringContentsOf(osu_filename, firstExport.GetBuffer()),
+                () => Is.EqualTo(getStringContentsOf(osu_filename, secondExport.GetBuffer())));
+
+            string getStringContentsOf(string filename, byte[] archiveBytes)
+            {
+                using var memoryStream = new MemoryStream(archiveBytes);
+                using var archiveReader = new ZipArchiveReader(memoryStream);
+                byte[] fileContent = archiveReader.GetStream(filename).ReadAllBytesToArray();
+                return Encoding.UTF8.GetString(fileContent);
+            }
+        }
+
         private IWorkingBeatmap importBeatmapFromStream(Stream stream)
         {
             var imported = beatmaps.Import(new ImportTask(stream, "filename.osz")).GetResultSafely();

osu.Game.Tests/NonVisual/Multiplayer/StatefulMultiplayerClientTest.cs

@@ -73,7 +73,7 @@ namespace osu.Game.Tests.NonVisual.Multiplayer
             AddStep("create room initially in gameplay", () =>
             {
                 var newRoom = new Room();
-                newRoom.CopyFrom(SelectedRoom.Value);
+                newRoom.CopyFrom(SelectedRoom.Value!);
 
                 newRoom.RoomID = null;
                 MultiplayerClient.RoomSetupAction = room =>

osu.Game.Tests/OnlinePlay/TestSceneCatchUpSyncManager.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 NUnit.Framework;
@@ -21,12 +19,12 @@ namespace osu.Game.Tests.OnlinePlay
     [HeadlessTest]
     public partial class TestSceneCatchUpSyncManager : OsuTestScene
     {
-        private GameplayClockContainer master;
+        private GameplayClockContainer master = null!;
-        private SpectatorSyncManager syncManager;
+        private SpectatorSyncManager syncManager = null!;
 
-        private Dictionary<SpectatorPlayerClock, int> clocksById;
+        private Dictionary<SpectatorPlayerClock, int> clocksById = null!;
-        private SpectatorPlayerClock player1;
+        private SpectatorPlayerClock player1 = null!;
-        private SpectatorPlayerClock player2;
+        private SpectatorPlayerClock player2 = null!;
 
         [SetUp]
         public void Setup()

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

@@ -18,6 +18,7 @@ using osu.Framework.Testing;
 using osu.Framework.Utils;
 using osu.Game.Beatmaps;
 using osu.Game.Configuration;
+using osu.Game.Graphics.UserInterface;
 using osu.Game.Overlays;
 using osu.Game.Overlays.Notifications;
 using osu.Game.Rulesets.Mods;
@@ -207,7 +208,25 @@ namespace osu.Game.Tests.Visual.Gameplay
         }
 
         [Test]
-        public void TestBlockLoadViaFocus()
+        public void TestLoadNotBlockedViaArbitraryFocus()
+        {
+            AddStep("load dummy beatmap", () => resetPlayer(false));
+            AddUntilStep("wait for current", () => loader.IsCurrentScreen());
+
+            AddUntilStep("click settings slider", () =>
+            {
+                InputManager.MoveMouseTo(loader.ChildrenOfType<OsuSliderBar<float>>().First());
+                InputManager.Click(MouseButton.Left);
+
+                return InputManager.FocusedDrawable is OsuSliderBar<float>;
+            });
+
+            AddUntilStep("wait for load ready", () => player?.LoadState == LoadState.Ready);
+            AddUntilStep("loads", () => !loader.IsCurrentScreen());
+        }
+
+        [Test]
+        public void TestBlockLoadViaOverlayFocus()
         {
             AddStep("load dummy beatmap", () => resetPlayer(false));
             AddUntilStep("wait for current", () => loader.IsCurrentScreen());

osu.Game.Tests/Visual/Mods/TestSceneModAccuracyChallenge.cs

@@ -35,7 +35,7 @@ namespace osu.Game.Tests.Visual.Mods
                     MinimumAccuracy = { Value = 0.6 }
                 },
                 Autoplay = false,
-                Beatmap = new Beatmap
+                CreateBeatmap = () => new Beatmap
                 {
                     HitObjects = Enumerable.Range(0, 5).Select(i => new HitCircle
                     {
@@ -56,7 +56,7 @@ namespace osu.Game.Tests.Visual.Mods
                     AccuracyJudgeMode = { Value = ModAccuracyChallenge.AccuracyMode.Standard }
                 },
                 Autoplay = false,
-                Beatmap = new Beatmap
+                CreateBeatmap = () => new Beatmap
                 {
                     HitObjects = Enumerable.Range(0, 5).Select(i => new HitCircle
                     {

osu.Game.Tests/Visual/Multiplayer/MultiplayerGameplayLeaderboardTestScene.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.Collections.Specialized;
@@ -31,7 +29,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
 
         protected readonly BindableList<MultiplayerRoomUser> MultiplayerUsers = new BindableList<MultiplayerRoomUser>();
 
-        protected MultiplayerGameplayLeaderboard Leaderboard { get; private set; }
+        protected MultiplayerGameplayLeaderboard? Leaderboard { get; private set; }
 
         protected virtual MultiplayerRoomUser CreateUser(int userId) => new MultiplayerRoomUser(userId);
 
@@ -40,7 +38,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
         private readonly BindableList<int> multiplayerUserIds = new BindableList<int>();
         private readonly BindableDictionary<int, SpectatorState> watchedUserStates = new BindableDictionary<int, SpectatorState>();
 
-        private OsuConfigManager config;
+        private OsuConfigManager config = null!;
 
         private readonly Mock<SpectatorClient> spectatorClient = new Mock<SpectatorClient>();
         private readonly Mock<MultiplayerClient> multiplayerClient = new Mock<MultiplayerClient>();
@@ -133,7 +131,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
                 LoadComponentAsync(Leaderboard = CreateLeaderboard(), Add);
             });
 
-            AddUntilStep("wait for load", () => Leaderboard.IsLoaded);
+            AddUntilStep("wait for load", () => Leaderboard!.IsLoaded);
 
             AddStep("check watch requests were sent", () =>
             {
@@ -146,7 +144,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
         public void TestScoreUpdates()
         {
             AddRepeatStep("update state", UpdateUserStatesRandomly, 100);
-            AddToggleStep("switch compact mode", expanded => Leaderboard.Expanded.Value = expanded);
+            AddToggleStep("switch compact mode", expanded => Leaderboard!.Expanded.Value = expanded);
         }
 
         [Test]

osu.Game.Tests/Visual/Multiplayer/TestSceneCreateMultiplayerMatchButton.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 NUnit.Framework;
 using osu.Framework.Graphics;
@@ -12,7 +10,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
 {
     public partial class TestSceneCreateMultiplayerMatchButton : MultiplayerTestScene
     {
-        private CreateMultiplayerMatchButton button;
+        private CreateMultiplayerMatchButton button = null!;
 
         public override void SetUpSteps()
         {
@@ -29,7 +27,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
         [Test]
         public void TestButtonEnableStateChanges()
         {
-            IDisposable joiningRoomOperation = null;
+            IDisposable joiningRoomOperation = null!;
 
             assertButtonEnableState(true);
 

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

@@ -119,7 +119,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
             AddAssert("4 circles displayed", () => list.ChildrenOfType<UpdateableAvatar>().Count() == 4);
             AddAssert("46 hidden users", () => list.ChildrenOfType<DrawableRoomParticipantsList.HiddenUserCount>().Single().Count == 46);
 
-            AddStep("remove from end", () => removeUserAt(SelectedRoom.Value.RecentParticipants.Count - 1));
+            AddStep("remove from end", () => removeUserAt(SelectedRoom.Value!.RecentParticipants.Count - 1));
             AddAssert("4 circles displayed", () => list.ChildrenOfType<UpdateableAvatar>().Count() == 4);
             AddAssert("45 hidden users", () => list.ChildrenOfType<DrawableRoomParticipantsList.HiddenUserCount>().Single().Count == 45);
 
@@ -138,18 +138,18 @@ namespace osu.Game.Tests.Visual.Multiplayer
 
         private void addUser(int id)
         {
-            SelectedRoom.Value.RecentParticipants = SelectedRoom.Value.RecentParticipants.Append(new APIUser
+            SelectedRoom.Value!.RecentParticipants = SelectedRoom.Value!.RecentParticipants.Append(new APIUser
             {
                 Id = id,
                 Username = $"User {id}"
             }).ToArray();
-            SelectedRoom.Value.ParticipantCount++;
+            SelectedRoom.Value!.ParticipantCount++;
         }
 
         private void removeUserAt(int index)
         {
-            SelectedRoom.Value.RecentParticipants = SelectedRoom.Value.RecentParticipants.Where(u => !u.Equals(SelectedRoom.Value.RecentParticipants[index])).ToArray();
+            SelectedRoom.Value!.RecentParticipants = SelectedRoom.Value!.RecentParticipants.Where(u => !u.Equals(SelectedRoom.Value!.RecentParticipants[index])).ToArray();
-            SelectedRoom.Value.ParticipantCount--;
+            SelectedRoom.Value!.ParticipantCount--;
         }
     }
 }

osu.Game.Tests/Visual/Multiplayer/TestSceneDrawableRoomPlaylist.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.Diagnostics;
@@ -39,9 +37,8 @@ namespace osu.Game.Tests.Visual.Multiplayer
 {
     public partial class TestSceneDrawableRoomPlaylist : MultiplayerTestScene
     {
-        private TestPlaylist playlist;
+        private TestPlaylist playlist = null!;
-
+        private BeatmapManager manager = null!;
-        private BeatmapManager manager;
 
         [BackgroundDependencyLoader]
         private void load(GameHost host, AudioManager audio)
@@ -199,14 +196,14 @@ namespace osu.Game.Tests.Visual.Multiplayer
         [Test]
         public void TestDownloadButtonHiddenWhenBeatmapExists()
         {
-            Live<BeatmapSetInfo> imported = null;
+            Live<BeatmapSetInfo> imported = null!;
 
             AddStep("import beatmap", () =>
             {
                 var beatmap = new TestBeatmap(new OsuRuleset().RulesetInfo).BeatmapInfo;
 
                 Debug.Assert(beatmap.BeatmapSet != null);
-                imported = manager.Import(beatmap.BeatmapSet);
+                imported = manager.Import(beatmap.BeatmapSet)!;
             });
 
             createPlaylistWithBeatmaps(() => imported.PerformRead(s => s.Beatmaps.Detach()));
@@ -378,7 +375,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
             }
         });
 
-        private void createPlaylist(Action<TestPlaylist> setupPlaylist = null)
+        private void createPlaylist(Action<TestPlaylist>? setupPlaylist = null)
         {
             AddStep("create playlist", () =>
             {

osu.Game.Tests/Visual/Multiplayer/TestSceneFreeModSelectOverlay.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;
@@ -26,9 +24,9 @@ namespace osu.Game.Tests.Visual.Multiplayer
 {
     public partial class TestSceneFreeModSelectOverlay : MultiplayerTestScene
     {
-        private FreeModSelectOverlay freeModSelectOverlay;
+        private FreeModSelectOverlay freeModSelectOverlay = null!;
-        private FooterButtonFreeMods footerButtonFreeMods;
+        private FooterButtonFreeMods footerButtonFreeMods = null!;
-        private ScreenFooter footer;
+        private ScreenFooter footer = null!;
         private readonly Bindable<Dictionary<ModType, IReadOnlyList<Mod>>> availableMods = new Bindable<Dictionary<ModType, IReadOnlyList<Mod>>>();
 
         [BackgroundDependencyLoader]
@@ -49,7 +47,6 @@ namespace osu.Game.Tests.Visual.Multiplayer
 
             AddToggleStep("toggle visibility", visible =>
             {
-                if (freeModSelectOverlay != null)
                 freeModSelectOverlay.State.Value = visible ? Visibility.Visible : Visibility.Hidden;
             });
         }

osu.Game.Tests/Visual/Multiplayer/TestSceneGameplayChatDisplay.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 Moq;
 using NUnit.Framework;
@@ -20,7 +18,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
 {
     public partial class TestSceneGameplayChatDisplay : OsuManualInputManagerTestScene
     {
-        private GameplayChatDisplay chatDisplay;
+        private GameplayChatDisplay chatDisplay = null!;
 
         [Cached(typeof(ILocalUserPlayInfo))]
         private ILocalUserPlayInfo localUserInfo;

osu.Game.Tests/Visual/Multiplayer/TestSceneHostOnlyQueueMode.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.Linq;
 using NUnit.Framework;
@@ -70,13 +68,13 @@ namespace osu.Game.Tests.Visual.Multiplayer
         {
             RunGameplay();
 
-            IBeatmapInfo firstBeatmap = null;
+            IBeatmapInfo firstBeatmap = null!;
-            AddStep("get first playlist item beatmap", () => firstBeatmap = MultiplayerClient.ServerAPIRoom?.Playlist[0].Beatmap);
+            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("first playlist item hasn't changed", () => MultiplayerClient.ServerAPIRoom!.Playlist[0].Beatmap == firstBeatmap);
-            AddUntilStep("second playlist item changed", () => MultiplayerClient.ClientAPIRoom?.Playlist[1].Beatmap != firstBeatmap);
+            AddUntilStep("second playlist item changed", () => MultiplayerClient.ClientAPIRoom!.Playlist[1].Beatmap != firstBeatmap);
         }
 
         [Test]
@@ -103,7 +101,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
 
             AddUntilStep("wait for song select", () => CurrentSubScreen is Screens.Select.SongSelect select && select.BeatmapSetsLoaded);
 
-            BeatmapInfo otherBeatmap = null;
+            BeatmapInfo otherBeatmap = null!;
             AddStep("select other beatmap", () => ((Screens.Select.SongSelect)CurrentSubScreen).FinaliseSelection(otherBeatmap = beatmap()));
 
             AddUntilStep("wait for return to match", () => CurrentSubScreen is MultiplayerMatchSubScreen);

osu.Game.Tests/Visual/Multiplayer/TestSceneLoungeRoomsContainer.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;
@@ -23,7 +21,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
     {
         protected new TestRoomManager RoomManager => (TestRoomManager)base.RoomManager;
 
-        private RoomsContainer container;
+        private RoomsContainer container = null!;
 
         public override void SetUpSteps()
         {
@@ -65,7 +63,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
             AddStep("select first room", () => container.Rooms.First().TriggerClick());
             AddAssert("first spotlight selected", () => checkRoomSelected(RoomManager.Rooms.First(r => r.Category == RoomCategory.Spotlight)));
 
-            AddStep("remove last room", () => RoomManager.RemoveRoom(RoomManager.Rooms.MinBy(r => r.RoomID)));
+            AddStep("remove last room", () => RoomManager.RemoveRoom(RoomManager.Rooms.MinBy(r => r.RoomID)!));
             AddAssert("first spotlight still selected", () => checkRoomSelected(RoomManager.Rooms.First(r => r.Category == RoomCategory.Spotlight)));
 
             AddStep("remove spotlight room", () => RoomManager.RemoveRoom(RoomManager.Rooms.Single(r => r.Category == RoomCategory.Spotlight)));
@@ -157,7 +155,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
             AddStep("add rooms", () => RoomManager.AddRooms(3, new CatchRuleset().RulesetInfo));
 
             // Todo: What even is this case...?
-            AddStep("set empty filter criteria", () => container.Filter.Value = null);
+            AddStep("set empty filter criteria", () => container.Filter.Value = new FilterCriteria());
             AddUntilStep("5 rooms visible", () => container.Rooms.Count(r => r.IsPresent) == 5);
 
             AddStep("filter osu! rooms", () => container.Filter.Value = new FilterCriteria { Ruleset = new OsuRuleset().RulesetInfo });
@@ -195,9 +193,9 @@ namespace osu.Game.Tests.Visual.Multiplayer
             AddStep("add rooms", () => RoomManager.AddRooms(3, withPassword: true));
         }
 
-        private bool checkRoomSelected(Room room) => SelectedRoom.Value == room;
+        private bool checkRoomSelected(Room? room) => SelectedRoom.Value == room;
 
-        private Room getRoomInFlow(int index) =>
+        private Room? getRoomInFlow(int index) =>
             (container.ChildrenOfType<FillFlowContainer<DrawableLoungeRoom>>().First().FlowingChildren.ElementAt(index) as DrawableRoom)?.Room;
     }
 }

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

@@ -36,7 +36,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
 
         private void createNewItem()
         {
-            SelectedRoom.Value.Playlist = SelectedRoom.Value.Playlist.Append(new PlaylistItem(new TestBeatmap(new OsuRuleset().RulesetInfo).BeatmapInfo)
+            SelectedRoom.Value!.Playlist = SelectedRoom.Value.Playlist.Append(new PlaylistItem(new TestBeatmap(new OsuRuleset().RulesetInfo).BeatmapInfo)
             {
                 ID = SelectedRoom.Value.Playlist.Count,
                 RulesetID = new OsuRuleset().RulesetInfo.OnlineID,

osu.Game.Tests/Visual/Multiplayer/TestSceneMultiSpectatorLeaderboard.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 NUnit.Framework;
@@ -18,8 +16,8 @@ namespace osu.Game.Tests.Visual.Multiplayer
 {
     public partial class TestSceneMultiSpectatorLeaderboard : MultiplayerTestScene
     {
-        private Dictionary<int, ManualClock> clocks;
+        private Dictionary<int, ManualClock> clocks = null!;
-        private MultiSpectatorLeaderboard leaderboard;
+        private MultiSpectatorLeaderboard? leaderboard;
 
         [SetUpSteps]
         public override void SetUpSteps()
@@ -55,13 +53,13 @@ namespace osu.Game.Tests.Visual.Multiplayer
                 }, Add);
             });
 
-            AddUntilStep("wait for load", () => leaderboard.IsLoaded);
+            AddUntilStep("wait for load", () => leaderboard!.IsLoaded);
             AddUntilStep("wait for user population", () => leaderboard.ChildrenOfType<GameplayLeaderboardScore>().Count() == 2);
 
             AddStep("add clock sources", () =>
             {
                 foreach ((int userId, var clock) in clocks)
-                    leaderboard.AddClock(userId, clock);
+                    leaderboard!.AddClock(userId, clock);
             });
         }
 

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

@@ -455,7 +455,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
 
                 applyToBeatmap?.Invoke(Beatmap.Value);
 
-                LoadScreen(spectatorScreen = new MultiSpectatorScreen(SelectedRoom.Value, playingUsers.ToArray()));
+                LoadScreen(spectatorScreen = new MultiSpectatorScreen(SelectedRoom.Value!, playingUsers.ToArray()));
             });
 
             AddUntilStep("wait for screen load", () => spectatorScreen.LoadState == LoadState.Loaded && (!waitForPlayerLoad || spectatorScreen.AllPlayersLoaded));

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

@@ -37,10 +37,10 @@ namespace osu.Game.Tests.Visual.Multiplayer
         [Test]
         public void TestPerUserMods()
         {
-            AddStep("first user has no mods", () => Assert.That(((TestLeaderboard)Leaderboard).UserMods[0], Is.Empty));
+            AddStep("first user has no mods", () => Assert.That(((TestLeaderboard)Leaderboard!).UserMods[0], Is.Empty));
             AddStep("last user has NF mod", () =>
             {
-                Assert.That(((TestLeaderboard)Leaderboard).UserMods[TOTAL_USERS - 1], Has.One.Items);
+                Assert.That(((TestLeaderboard)Leaderboard!).UserMods[TOTAL_USERS - 1], Has.One.Items);
                 Assert.That(((TestLeaderboard)Leaderboard).UserMods[TOTAL_USERS - 1].Single(), Is.TypeOf<OsuModNoFail>());
             });
         }

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

@@ -39,7 +39,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
             {
                 LoadComponentAsync(new MatchScoreDisplay
                 {
-                    Team1Score = { BindTarget = Leaderboard.TeamScores[0] },
+                    Team1Score = { BindTarget = Leaderboard!.TeamScores[0] },
                     Team2Score = { BindTarget = Leaderboard.TeamScores[1] }
                 }, Add);
 

osu.Game.Tests/Visual/Multiplayer/TestSceneMultiplayerLoungeSubScreen.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;
@@ -22,10 +20,9 @@ namespace osu.Game.Tests.Visual.Multiplayer
     {
         protected new TestRoomManager RoomManager => (TestRoomManager)base.RoomManager;
 
-        private LoungeSubScreen loungeScreen;
+        private LoungeSubScreen loungeScreen = null!;
-
+        private Room? lastJoinedRoom;
-        private Room lastJoinedRoom;
+        private string? lastJoinedPassword;
-        private string lastJoinedPassword;
 
         public override void SetUpSteps()
         {
@@ -87,7 +84,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
         [Test]
         public void TestJoinRoomWithIncorrectPasswordViaButton()
         {
-            DrawableLoungeRoom.PasswordEntryPopover passwordEntryPopover = null;
+            DrawableLoungeRoom.PasswordEntryPopover? passwordEntryPopover = null;
 
             AddStep("add room", () => RoomManager.AddRooms(1, withPassword: true));
             AddStep("select room", () => InputManager.Key(Key.Down));
@@ -97,14 +94,14 @@ namespace osu.Game.Tests.Visual.Multiplayer
             AddStep("press join room button", () => passwordEntryPopover.ChildrenOfType<OsuButton>().First().TriggerClick());
 
             AddAssert("room not joined", () => loungeScreen.IsCurrentScreen());
-            AddUntilStep("password prompt still visible", () => passwordEntryPopover.State.Value == Visibility.Visible);
+            AddUntilStep("password prompt still visible", () => passwordEntryPopover!.State.Value == Visibility.Visible);
             AddAssert("textbox still focused", () => InputManager.FocusedDrawable is OsuPasswordTextBox);
         }
 
         [Test]
         public void TestJoinRoomWithIncorrectPasswordViaEnter()
         {
-            DrawableLoungeRoom.PasswordEntryPopover passwordEntryPopover = null;
+            DrawableLoungeRoom.PasswordEntryPopover? passwordEntryPopover = null;
 
             AddStep("add room", () => RoomManager.AddRooms(1, withPassword: true));
             AddStep("select room", () => InputManager.Key(Key.Down));
@@ -114,14 +111,14 @@ namespace osu.Game.Tests.Visual.Multiplayer
             AddStep("press enter", () => InputManager.Key(Key.Enter));
 
             AddAssert("room not joined", () => loungeScreen.IsCurrentScreen());
-            AddUntilStep("password prompt still visible", () => passwordEntryPopover.State.Value == Visibility.Visible);
+            AddUntilStep("password prompt still visible", () => passwordEntryPopover!.State.Value == Visibility.Visible);
             AddAssert("textbox still focused", () => InputManager.FocusedDrawable is OsuPasswordTextBox);
         }
 
         [Test]
         public void TestJoinRoomWithCorrectPassword()
         {
-            DrawableLoungeRoom.PasswordEntryPopover passwordEntryPopover = null;
+            DrawableLoungeRoom.PasswordEntryPopover? passwordEntryPopover = null;
 
             AddStep("add room", () => RoomManager.AddRooms(1, withPassword: true));
             AddStep("select room", () => InputManager.Key(Key.Down));
@@ -137,7 +134,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
         [Test]
         public void TestJoinRoomWithPasswordViaKeyboardOnly()
         {
-            DrawableLoungeRoom.PasswordEntryPopover passwordEntryPopover = null;
+            DrawableLoungeRoom.PasswordEntryPopover? passwordEntryPopover = null;
 
             AddStep("add room", () => RoomManager.AddRooms(1, withPassword: true));
             AddStep("select room", () => InputManager.Key(Key.Down));
@@ -150,7 +147,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
             AddAssert("room join password correct", () => lastJoinedPassword == "password");
         }
 
-        private void onRoomJoined(Room room, string password)
+        private void onRoomJoined(Room room, string? password)
         {
             lastJoinedRoom = room;
             lastJoinedPassword = password;

osu.Game.Tests/Visual/Multiplayer/TestSceneMultiplayerMatchSongSelect.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 NUnit.Framework;
 using osu.Framework.Allocation;
 using osu.Framework.Audio;
@@ -35,17 +32,16 @@ namespace osu.Game.Tests.Visual.Multiplayer
 {
     public partial class TestSceneMultiplayerMatchSongSelect : MultiplayerTestScene
     {
-        private BeatmapManager manager;
+        private BeatmapManager manager = null!;
-        private RulesetStore rulesets;
+        private RulesetStore rulesets = null!;
 
-        private IList<BeatmapInfo> beatmaps => importedBeatmapSet?.PerformRead(s => s.Beatmaps) ?? new List<BeatmapInfo>();
+        private IList<BeatmapInfo> beatmaps => importedBeatmapSet.PerformRead(s => s.Beatmaps);
 
-        private TestMultiplayerMatchSongSelect songSelect;
+        private TestMultiplayerMatchSongSelect songSelect = null!;
-
+        private Live<BeatmapSetInfo> importedBeatmapSet = null!;
-        private Live<BeatmapSetInfo> importedBeatmapSet;
 
         [Resolved]
-        private OsuConfigManager configManager { get; set; }
+        private OsuConfigManager configManager { get; set; } = null!;
 
         [BackgroundDependencyLoader]
         private void load(GameHost host, AudioManager audio)
@@ -57,7 +53,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
             Dependencies.Cache(detachedBeatmapStore = new DetachedBeatmapStore());
             Dependencies.Cache(Realm);
 
-            importedBeatmapSet = manager.Import(TestResources.CreateTestBeatmapSetInfo(8, rulesets.AvailableRulesets.ToArray()));
+            importedBeatmapSet = manager.Import(TestResources.CreateTestBeatmapSetInfo(8, rulesets.AvailableRulesets.ToArray()))!;
 
             Add(detachedBeatmapStore);
         }
@@ -71,7 +67,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
                 SelectedMods.SetDefault();
             });
 
-            AddStep("create song select", () => LoadScreen(songSelect = new TestMultiplayerMatchSongSelect(SelectedRoom.Value)));
+            AddStep("create song select", () => LoadScreen(songSelect = new TestMultiplayerMatchSongSelect(SelectedRoom.Value!)));
             AddUntilStep("wait for present", () => songSelect.IsCurrentScreen() && songSelect.BeatmapSetsLoaded);
         }
 
@@ -88,7 +84,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
         [Test]
         public void TestBeatmapConfirmed()
         {
-            BeatmapInfo selectedBeatmap = null;
+            BeatmapInfo selectedBeatmap = null!;
 
             setUp();
 
@@ -117,8 +113,8 @@ namespace osu.Game.Tests.Visual.Multiplayer
             setUp();
 
             AddStep("change ruleset", () => Ruleset.Value = new OsuRuleset().RulesetInfo);
-            AddStep($"select {allowedMod.ReadableName()} as allowed", () => songSelect.FreeMods.Value = new[] { (Mod)Activator.CreateInstance(allowedMod) });
+            AddStep($"select {allowedMod.ReadableName()} as allowed", () => songSelect.FreeMods.Value = new[] { (Mod)Activator.CreateInstance(allowedMod)! });
-            AddStep($"select {requiredMod.ReadableName()} as required", () => songSelect.Mods.Value = new[] { (Mod)Activator.CreateInstance(requiredMod) });
+            AddStep($"select {requiredMod.ReadableName()} as required", () => songSelect.Mods.Value = new[] { (Mod)Activator.CreateInstance(requiredMod)! });
 
             AddAssert("freemods empty", () => songSelect.FreeMods.Value.Count == 0);
 
@@ -141,7 +137,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
 
             AddStep("create song select", () =>
             {
-                SelectedRoom.Value.Playlist.Single().RulesetID = 2;
+                SelectedRoom.Value!.Playlist.Single().RulesetID = 2;
                 songSelect = new TestMultiplayerMatchSongSelect(SelectedRoom.Value, SelectedRoom.Value.Playlist.Single());
                 songSelect.OnLoadComplete += _ => Ruleset.Value = new TaikoRuleset().RulesetInfo;
                 LoadScreen(songSelect);
@@ -171,7 +167,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
 
             public new BeatmapCarousel Carousel => base.Carousel;
 
-            public TestMultiplayerMatchSongSelect(Room room, [CanBeNull] PlaylistItem itemToEdit = null)
+            public TestMultiplayerMatchSongSelect(Room room, PlaylistItem? itemToEdit = null)
                 : base(room, itemToEdit)
             {
             }

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

@@ -1,10 +1,7 @@
 // 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 JetBrains.Annotations;
 using NUnit.Framework;
 using osu.Framework.Allocation;
 using osu.Framework.Audio;
@@ -42,10 +39,9 @@ namespace osu.Game.Tests.Visual.Multiplayer
 {
     public partial class TestSceneMultiplayerMatchSubScreen : MultiplayerTestScene
     {
-        private MultiplayerMatchSubScreen screen;
+        private MultiplayerMatchSubScreen screen = null!;
-
+        private BeatmapManager beatmaps = null!;
-        private BeatmapManager beatmaps;
+        private BeatmapSetInfo importedSet = null!;
-        private BeatmapSetInfo importedSet;
 
         public TestSceneMultiplayerMatchSubScreen()
             : base(false)
@@ -70,7 +66,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
             AddStep("load match", () =>
             {
                 SelectedRoom.Value = new Room { Name = "Test Room" };
-                LoadScreen(screen = new TestMultiplayerMatchSubScreen(SelectedRoom.Value));
+                LoadScreen(screen = new TestMultiplayerMatchSubScreen(SelectedRoom.Value!));
             });
 
             AddUntilStep("wait for load", () => screen.IsCurrentScreen());
@@ -81,7 +77,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
         {
             AddStep("add playlist item", () =>
             {
-                SelectedRoom.Value.Playlist =
+                SelectedRoom.Value!.Playlist =
                 [
                     new PlaylistItem(new TestBeatmap(new OsuRuleset().RulesetInfo).BeatmapInfo)
                     {
@@ -100,7 +96,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
         {
             AddStep("add playlist item", () =>
             {
-                SelectedRoom.Value.Playlist =
+                SelectedRoom.Value!.Playlist =
                 [
                     new PlaylistItem(new TestBeatmap(new TaikoRuleset().RulesetInfo).BeatmapInfo)
                     {
@@ -125,7 +121,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
 
             AddStep("set playlist", () =>
             {
-                SelectedRoom.Value.Playlist =
+                SelectedRoom.Value!.Playlist =
                 [
                     new PlaylistItem(new TestBeatmap(new OsuRuleset().RulesetInfo).BeatmapInfo)
                     {
@@ -142,7 +138,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
         {
             AddStep("set playlist", () =>
             {
-                SelectedRoom.Value.Playlist =
+                SelectedRoom.Value!.Playlist =
                 [
                     new PlaylistItem(beatmaps.GetWorkingBeatmap(importedSet.Beatmaps.First()).BeatmapInfo)
                     {
@@ -173,7 +169,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
         {
             AddStep("add playlist item with allowed mod", () =>
             {
-                SelectedRoom.Value.Playlist =
+                SelectedRoom.Value!.Playlist =
                 [
                     new PlaylistItem(new TestBeatmap(new OsuRuleset().RulesetInfo).BeatmapInfo)
                     {
@@ -202,7 +198,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
         {
             AddStep("add playlist item with allowed mod", () =>
             {
-                SelectedRoom.Value.Playlist =
+                SelectedRoom.Value!.Playlist =
                 [
                     new PlaylistItem(new TestBeatmap(new OsuRuleset().RulesetInfo).BeatmapInfo)
                     {
@@ -226,7 +222,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
         {
             AddStep("add playlist item with no allowed mods", () =>
             {
-                SelectedRoom.Value.Playlist =
+                SelectedRoom.Value!.Playlist =
                 [
                     new PlaylistItem(new TestBeatmap(new OsuRuleset().RulesetInfo).BeatmapInfo)
                     {
@@ -249,7 +245,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
         {
             AddStep("add two playlist items", () =>
             {
-                SelectedRoom.Value.Playlist =
+                SelectedRoom.Value!.Playlist =
                 [
                     new PlaylistItem(beatmaps.GetWorkingBeatmap(importedSet.Beatmaps.First()).BeatmapInfo)
                     {
@@ -285,7 +281,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
         {
             AddStep("add playlist item", () =>
             {
-                SelectedRoom.Value.Playlist =
+                SelectedRoom.Value!.Playlist =
                 [
                     new PlaylistItem(new TestBeatmap(new OsuRuleset().RulesetInfo).BeatmapInfo)
                     {
@@ -320,8 +316,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
         private partial class TestMultiplayerMatchSubScreen : MultiplayerMatchSubScreen
         {
             [Resolved(canBeNull: true)]
-            [CanBeNull]
+            private IDialogOverlay? dialogOverlay { get; set; }
-            private IDialogOverlay dialogOverlay { get; set; }
 
             public TestMultiplayerMatchSubScreen(Room room)
                 : base(room)

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

@@ -48,7 +48,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
 
             AddStep("create list", () =>
             {
-                Child = list = new MultiplayerPlaylist(SelectedRoom.Value)
+                Child = list = new MultiplayerPlaylist(SelectedRoom.Value!)
                 {
                     Anchor = Anchor.Centre,
                     Origin = Anchor.Centre,

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

@@ -44,7 +44,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
 
             AddStep("create playlist", () =>
             {
-                Child = playlist = new MultiplayerQueueList(SelectedRoom.Value)
+                Child = playlist = new MultiplayerQueueList(SelectedRoom.Value!)
                 {
                     Anchor = Anchor.Centre,
                     Origin = Anchor.Centre,

osu.Game.Tests/Visual/Multiplayer/TestSceneMultiplayerResults.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 NUnit.Framework;
 using osu.Game.Online.Rooms;
 using osu.Game.Rulesets.Osu;
@@ -16,7 +14,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
         [Test]
         public void TestDisplayResults()
         {
-            MultiplayerResultsScreen screen = null;
+            MultiplayerResultsScreen screen = null!;
 
             AddStep("show results screen", () =>
             {

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

@@ -48,7 +48,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
 
             AddStep("create button", () =>
             {
-                PlaylistItem item = SelectedRoom.Value.Playlist.First();
+                PlaylistItem item = SelectedRoom.Value!.Playlist.First();
 
                 AvailabilityTracker.SelectedItem.Value = item;
 

osu.Game.Tests/Visual/Multiplayer/TestSceneMultiplayerSpectatorPlayerGrid.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;
@@ -16,7 +14,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
 {
     public partial class TestSceneMultiplayerSpectatorPlayerGrid : OsuManualInputManagerTestScene
     {
-        private PlayerGrid grid;
+        private PlayerGrid grid = null!;
 
         [SetUp]
         public void Setup() => Schedule(() =>

osu.Game.Tests/Visual/Multiplayer/TestSceneMultiplayerTeamResults.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 NUnit.Framework;
 using osu.Framework.Bindables;
@@ -32,7 +30,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
         [TestCase(1048576, 1048576)]
         public void TestDisplayTeamResults(int team1Score, int team2Score)
         {
-            MultiplayerResultsScreen screen = null;
+            MultiplayerResultsScreen screen = null!;
 
             AddStep("show results screen", () =>
             {

osu.Game.Tests/Visual/Multiplayer/TestScenePlaylistsRoomSettingsPlaylist.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;
@@ -28,18 +26,18 @@ namespace osu.Game.Tests.Visual.Multiplayer
 {
     public partial class TestScenePlaylistsRoomSettingsPlaylist : OnlinePlayTestScene
     {
-        private TestPlaylist playlist;
+        private TestPlaylist playlist = null!;
 
         [Test]
         public void TestItemRemovedOnDeletion()
         {
-            PlaylistItem selectedItem = null;
+            PlaylistItem selectedItem = null!;
 
             createPlaylist();
 
             moveToItem(0);
             AddStep("click", () => InputManager.Click(MouseButton.Left));
-            AddStep("retrieve selection", () => selectedItem = playlist.SelectedItem.Value);
+            AddStep("retrieve selection", () => selectedItem = playlist.SelectedItem.Value!);
 
             moveToDeleteButton(0);
             AddStep("click delete button", () => InputManager.Click(MouseButton.Left));
@@ -122,7 +120,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
             InputManager.MoveMouseTo(item.ChildrenOfType<DrawableRoomPlaylistItem.PlaylistRemoveButton>().ElementAt(0), offset);
         });
 
-        private void createPlaylist(Action<TestPlaylist> setupPlaylist = null)
+        private void createPlaylist(Action<TestPlaylist>? setupPlaylist = null)
         {
             AddStep("create playlist", () =>
             {

osu.Game.Tests/Visual/Multiplayer/TestScenePlaylistsSongSelect.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.Linq;
 using NUnit.Framework;
@@ -27,9 +25,8 @@ namespace osu.Game.Tests.Visual.Multiplayer
 {
     public partial class TestScenePlaylistsSongSelect : OnlinePlayTestScene
     {
-        private BeatmapManager manager;
+        private BeatmapManager manager = null!;
-
+        private TestPlaylistsSongSelect songSelect = null!;
-        private TestPlaylistsSongSelect songSelect;
 
         [BackgroundDependencyLoader]
         private void load(GameHost host, AudioManager audio)
@@ -60,7 +57,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
                 SelectedMods.Value = Array.Empty<Mod>();
             });
 
-            AddStep("create song select", () => LoadScreen(songSelect = new TestPlaylistsSongSelect(SelectedRoom.Value)));
+            AddStep("create song select", () => LoadScreen(songSelect = new TestPlaylistsSongSelect(SelectedRoom.Value!)));
             AddUntilStep("wait for present", () => songSelect.IsCurrentScreen() && songSelect.BeatmapSetsLoaded);
         }
 
@@ -68,14 +65,14 @@ namespace osu.Game.Tests.Visual.Multiplayer
         public void TestItemAddedIfEmptyOnStart()
         {
             AddStep("finalise selection", () => songSelect.FinaliseSelection());
-            AddAssert("playlist has 1 item", () => SelectedRoom.Value.Playlist.Count == 1);
+            AddAssert("playlist has 1 item", () => SelectedRoom.Value!.Playlist.Count == 1);
         }
 
         [Test]
         public void TestItemAddedWhenCreateNewItemClicked()
         {
             AddStep("create new item", () => songSelect.BeatmapDetails.CreateNewItem!());
-            AddAssert("playlist has 1 item", () => SelectedRoom.Value.Playlist.Count == 1);
+            AddAssert("playlist has 1 item", () => SelectedRoom.Value!.Playlist.Count == 1);
         }
 
         [Test]
@@ -83,7 +80,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
         {
             AddStep("create new item", () => songSelect.BeatmapDetails.CreateNewItem!());
             AddStep("finalise selection", () => songSelect.FinaliseSelection());
-            AddAssert("playlist has 1 item", () => SelectedRoom.Value.Playlist.Count == 1);
+            AddAssert("playlist has 1 item", () => SelectedRoom.Value!.Playlist.Count == 1);
         }
 
         [Test]
@@ -91,7 +88,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
         {
             AddStep("create new item", () => songSelect.BeatmapDetails.CreateNewItem!());
             AddStep("create new item", () => songSelect.BeatmapDetails.CreateNewItem!());
-            AddAssert("playlist has 2 items", () => SelectedRoom.Value.Playlist.Count == 2);
+            AddAssert("playlist has 2 items", () => SelectedRoom.Value!.Playlist.Count == 2);
         }
 
         [Test]
@@ -99,10 +96,10 @@ namespace osu.Game.Tests.Visual.Multiplayer
         {
             AddStep("create new item", () => songSelect.BeatmapDetails.CreateNewItem!());
             AddStep("create new item", () => songSelect.BeatmapDetails.CreateNewItem!());
-            AddStep("rearrange", () => SelectedRoom.Value.Playlist = SelectedRoom.Value.Playlist.Skip(1).Append(SelectedRoom.Value.Playlist[0]).ToArray());
+            AddStep("rearrange", () => SelectedRoom.Value!.Playlist = SelectedRoom.Value!.Playlist.Skip(1).Append(SelectedRoom.Value!.Playlist[0]).ToArray());
 
             AddStep("create new item", () => songSelect.BeatmapDetails.CreateNewItem!());
-            AddAssert("new item has id 2", () => SelectedRoom.Value.Playlist.Last().ID == 2);
+            AddAssert("new item has id 2", () => SelectedRoom.Value!.Playlist.Last().ID == 2);
         }
 
         /// <summary>
@@ -118,13 +115,13 @@ namespace osu.Game.Tests.Visual.Multiplayer
 
             AddAssert("item 1 has rate 1.5", () =>
             {
-                var mod = (OsuModDoubleTime)SelectedRoom.Value.Playlist.First().RequiredMods[0].ToMod(new OsuRuleset());
+                var mod = (OsuModDoubleTime)SelectedRoom.Value!.Playlist.First().RequiredMods[0].ToMod(new OsuRuleset());
                 return Precision.AlmostEquals(1.5, mod.SpeedChange.Value);
             });
 
             AddAssert("item 2 has rate 2", () =>
             {
-                var mod = (OsuModDoubleTime)SelectedRoom.Value.Playlist.Last().RequiredMods[0].ToMod(new OsuRuleset());
+                var mod = (OsuModDoubleTime)SelectedRoom.Value!.Playlist.Last().RequiredMods[0].ToMod(new OsuRuleset());
                 return Precision.AlmostEquals(2, mod.SpeedChange.Value);
             });
         }
@@ -135,7 +132,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
         [Test]
         public void TestGlobalModInstancesNotRetained()
         {
-            OsuModDoubleTime mod = null;
+            OsuModDoubleTime mod = null!;
 
             AddStep("set dt mod and store", () =>
             {
@@ -150,7 +147,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
             AddStep("change stored mod rate", () => mod.SpeedChange.Value = 2);
             AddAssert("item has rate 1.5", () =>
             {
-                var m = (OsuModDoubleTime)SelectedRoom.Value.Playlist.First().RequiredMods[0].ToMod(new OsuRuleset());
+                var m = (OsuModDoubleTime)SelectedRoom.Value!.Playlist.First().RequiredMods[0].ToMod(new OsuRuleset());
                 return Precision.AlmostEquals(1.5, m.SpeedChange.Value);
             });
         }

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

@@ -33,7 +33,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
         {
             AddStep("set playlist", () =>
             {
-                SelectedRoom.Value.Playlist =
+                SelectedRoom.Value!.Playlist =
                 [
                     new PlaylistItem(new BeatmapInfo { StarRating = min }),
                     new PlaylistItem(new BeatmapInfo { StarRating = max }),

osu.Game.Tests/Visual/Playlists/TestScenePlaylistsLoungeSubScreen.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.Bindables;
@@ -21,7 +19,7 @@ namespace osu.Game.Tests.Visual.Playlists
     {
         protected new TestRoomManager RoomManager => (TestRoomManager)base.RoomManager;
 
-        private TestLoungeSubScreen loungeScreen;
+        private TestLoungeSubScreen loungeScreen = null!;
 
         public override void SetUpSteps()
         {
@@ -97,7 +95,7 @@ namespace osu.Game.Tests.Visual.Playlists
 
         private partial class TestLoungeSubScreen : PlaylistsLoungeSubScreen
         {
-            public new Bindable<Room> SelectedRoom => base.SelectedRoom;
+            public new Bindable<Room?> SelectedRoom => base.SelectedRoom;
         }
     }
 }

osu.Game.Tests/Visual/Playlists/TestScenePlaylistsMatchSettingsOverlay.cs

@@ -32,7 +32,7 @@ namespace osu.Game.Tests.Visual.Playlists
             {
                 SelectedRoom.Value = new Room();
 
-                Child = settings = new TestRoomSettings(SelectedRoom.Value)
+                Child = settings = new TestRoomSettings(SelectedRoom.Value!)
                 {
                     RelativeSizeAxes = Axes.Both,
                     State = { Value = Visibility.Visible }
@@ -45,19 +45,19 @@ namespace osu.Game.Tests.Visual.Playlists
         {
             AddStep("clear name and beatmap", () =>
             {
-                SelectedRoom.Value.Name = "";
+                SelectedRoom.Value!.Name = "";
-                SelectedRoom.Value.Playlist = [];
+                SelectedRoom.Value!.Playlist = [];
             });
 
             AddAssert("button disabled", () => !settings.ApplyButton.Enabled.Value);
 
-            AddStep("set name", () => SelectedRoom.Value.Name = "Room name");
+            AddStep("set name", () => SelectedRoom.Value!.Name = "Room name");
             AddAssert("button disabled", () => !settings.ApplyButton.Enabled.Value);
 
-            AddStep("set beatmap", () => SelectedRoom.Value.Playlist = [new PlaylistItem(CreateBeatmap(Ruleset.Value).BeatmapInfo)]);
+            AddStep("set beatmap", () => SelectedRoom.Value!.Playlist = [new PlaylistItem(CreateBeatmap(Ruleset.Value).BeatmapInfo)]);
             AddAssert("button enabled", () => settings.ApplyButton.Enabled.Value);
 
-            AddStep("clear name", () => SelectedRoom.Value.Name = "");
+            AddStep("clear name", () => SelectedRoom.Value!.Name = "");
             AddAssert("button disabled", () => !settings.ApplyButton.Enabled.Value);
         }
 
@@ -73,7 +73,7 @@ namespace osu.Game.Tests.Visual.Playlists
             {
                 settings.NameField.Current.Value = expected_name;
                 settings.DurationField.Current.Value = expectedDuration;
-                SelectedRoom.Value.Playlist = [new PlaylistItem(CreateBeatmap(Ruleset.Value).BeatmapInfo)];
+                SelectedRoom.Value!.Playlist = [new PlaylistItem(CreateBeatmap(Ruleset.Value).BeatmapInfo)];
 
                 RoomManager.CreateRequested = r =>
                 {
@@ -98,8 +98,8 @@ namespace osu.Game.Tests.Visual.Playlists
             {
                 var beatmap = CreateBeatmap(Ruleset.Value).BeatmapInfo;
 
-                SelectedRoom.Value.Name = "Test Room";
+                SelectedRoom.Value!.Name = "Test Room";
-                SelectedRoom.Value.Playlist = [new PlaylistItem(beatmap)];
+                SelectedRoom.Value!.Playlist = [new PlaylistItem(beatmap)];
 
                 errorMessage = $"{not_found_prefix} {beatmap.OnlineID}";
 
@@ -107,13 +107,13 @@ namespace osu.Game.Tests.Visual.Playlists
             });
 
             AddAssert("error not displayed", () => !settings.ErrorText.IsPresent);
-            AddAssert("playlist item valid", () => SelectedRoom.Value.Playlist[0].Valid.Value);
+            AddAssert("playlist item valid", () => SelectedRoom.Value!.Playlist[0].Valid.Value);
 
             AddStep("create room", () => settings.ApplyButton.Action.Invoke());
 
             AddAssert("error displayed", () => settings.ErrorText.IsPresent);
             AddAssert("error has custom text", () => settings.ErrorText.Text != errorMessage);
-            AddAssert("playlist item marked invalid", () => !SelectedRoom.Value.Playlist[0].Valid.Value);
+            AddAssert("playlist item marked invalid", () => !SelectedRoom.Value!.Playlist[0].Valid.Value);
         }
 
         [Test]
@@ -125,8 +125,8 @@ namespace osu.Game.Tests.Visual.Playlists
 
             AddStep("setup", () =>
             {
-                SelectedRoom.Value.Name = "Test Room";
+                SelectedRoom.Value!.Name = "Test Room";
-                SelectedRoom.Value.Playlist = [new PlaylistItem(CreateBeatmap(Ruleset.Value).BeatmapInfo)];
+                SelectedRoom.Value!.Playlist = [new PlaylistItem(CreateBeatmap(Ruleset.Value).BeatmapInfo)];
 
                 RoomManager.CreateRequested = _ => failText;
             });

osu.Game.Tests/Visual/Playlists/TestScenePlaylistsParticipantsList.cs

@@ -38,7 +38,7 @@ namespace osu.Game.Tests.Visual.Playlists
         {
             AddStep("create component", () =>
             {
-                Child = new ParticipantsDisplay(SelectedRoom.Value, Direction.Horizontal)
+                Child = new ParticipantsDisplay(SelectedRoom.Value!, Direction.Horizontal)
                 {
                     Anchor = Anchor.Centre,
                     Origin = Anchor.Centre,
@@ -52,7 +52,7 @@ namespace osu.Game.Tests.Visual.Playlists
         {
             AddStep("create component", () =>
             {
-                Child = new ParticipantsDisplay(SelectedRoom.Value, Direction.Vertical)
+                Child = new ParticipantsDisplay(SelectedRoom.Value!, Direction.Vertical)
                 {
                     Anchor = Anchor.Centre,
                     Origin = Anchor.Centre,

osu.Game.Tests/Visual/Playlists/TestScenePlaylistsResultsScreen.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.Linq;
 using System.Net;
-using JetBrains.Annotations;
 using Newtonsoft.Json.Linq;
 using NUnit.Framework;
 using osu.Framework.Graphics.Containers;
@@ -34,14 +31,14 @@ namespace osu.Game.Tests.Visual.Playlists
         private const int scores_per_result = 10;
         private const int real_user_position = 200;
 
-        private TestResultsScreen resultsScreen;
+        private TestResultsScreen resultsScreen = null!;
 
         private int lowestScoreId; // Score ID of the lowest score in the list.
         private int highestScoreId; // Score ID of the highest score in the list.
 
         private bool requestComplete;
         private int totalCount;
-        private ScoreInfo userScore;
+        private ScoreInfo userScore = null!;
 
         [SetUpSteps]
         public override void SetUpSteps()
@@ -205,7 +202,7 @@ namespace osu.Game.Tests.Visual.Playlists
             AddAssert("placeholder shown", () => this.ChildrenOfType<MessagePlaceholder>().Count(), () => Is.EqualTo(1));
         }
 
-        private void createResults(Func<ScoreInfo> getScore = null)
+        private void createResults(Func<ScoreInfo>? getScore = null)
         {
             AddStep("load results", () =>
             {
@@ -229,7 +226,7 @@ namespace osu.Game.Tests.Visual.Playlists
             AddWaitStep("wait for display", 5);
         }
 
-        private void bindHandler(bool delayed = false, ScoreInfo userScore = null, bool failRequests = false, bool noScores = false) => ((DummyAPIAccess)API).HandleRequest = request =>
+        private void bindHandler(bool delayed = false, ScoreInfo? userScore = null, bool failRequests = false, bool noScores = false) => ((DummyAPIAccess)API).HandleRequest = request =>
         {
             // pre-check for requests we should be handling (as they are scheduled below).
             switch (request)
@@ -286,7 +283,7 @@ namespace osu.Game.Tests.Visual.Playlists
             req.TriggerFailure(new WebException("Failed."));
         }
 
-        private MultiplayerScore createUserResponse([NotNull] ScoreInfo userScore)
+        private MultiplayerScore createUserResponse(ScoreInfo userScore)
         {
             var multiplayerUserScore = new MultiplayerScore
             {
@@ -420,7 +417,7 @@ namespace osu.Game.Tests.Visual.Playlists
             public new LoadingSpinner RightSpinner => base.RightSpinner;
             public new ScorePanelList ScorePanelList => base.ScorePanelList;
 
-            public TestResultsScreen([CanBeNull] ScoreInfo score, int roomId, PlaylistItem playlistItem)
+            public TestResultsScreen(ScoreInfo? score, int roomId, PlaylistItem playlistItem)
                 : base(score, roomId, playlistItem)
             {
                 AllowRetry = true;

osu.Game.Tests/Visual/Playlists/TestScenePlaylistsRoomCreation.cs

@@ -51,7 +51,7 @@ namespace osu.Game.Tests.Visual.Playlists
 
             importBeatmap();
 
-            AddStep("load match", () => LoadScreen(match = new TestPlaylistsRoomSubScreen(SelectedRoom.Value)));
+            AddStep("load match", () => LoadScreen(match = new TestPlaylistsRoomSubScreen(SelectedRoom.Value!)));
             AddUntilStep("wait for load", () => match.IsCurrentScreen());
         }
 
@@ -119,7 +119,7 @@ namespace osu.Game.Tests.Visual.Playlists
                 ];
             });
 
-            AddAssert("first playlist item selected", () => match.SelectedItem.Value == SelectedRoom.Value.Playlist[0]);
+            AddAssert("first playlist item selected", () => match.SelectedItem.Value == SelectedRoom.Value!.Playlist[0]);
         }
 
         [Test]
@@ -199,7 +199,7 @@ namespace osu.Game.Tests.Visual.Playlists
 
         private void setupAndCreateRoom(Action<Room> room)
         {
-            AddStep("setup room", () => room(SelectedRoom.Value));
+            AddStep("setup room", () => room(SelectedRoom.Value!));
 
             AddStep("click create button", () =>
             {
@@ -218,7 +218,7 @@ namespace osu.Game.Tests.Visual.Playlists
 
         private partial class TestPlaylistsRoomSubScreen : PlaylistsRoomSubScreen
         {
-            public new Bindable<PlaylistItem> SelectedItem => base.SelectedItem;
+            public new Bindable<PlaylistItem?> SelectedItem => base.SelectedItem;
 
             public new Bindable<WorkingBeatmap> Beatmap => base.Beatmap;
 

osu.Game.Tests/Visual/Playlists/TestScenePlaylistsRoomSubScreen.cs

@@ -0,0 +1,41 @@
+// 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;
+using NUnit.Framework;
+using osu.Framework.Screens;
+using osu.Game.Online.API.Requests.Responses;
+using osu.Game.Online.Rooms;
+using osu.Game.Online.Rooms.RoomStatuses;
+using osu.Game.Screens.OnlinePlay.Playlists;
+using osu.Game.Tests.Visual.OnlinePlay;
+
+namespace osu.Game.Tests.Visual.Playlists
+{
+    public partial class TestScenePlaylistsRoomSubScreen : OnlinePlayTestScene
+    {
+        protected new TestRoomManager RoomManager => (TestRoomManager)base.RoomManager;
+
+        [Test]
+        public void TestStatusUpdateOnEnter()
+        {
+            Room room = null!;
+            PlaylistsRoomSubScreen roomScreen = null!;
+
+            AddStep("create room", () =>
+            {
+                RoomManager.AddRoom(room = new Room
+                {
+                    Name = @"Test Room",
+                    Host = new APIUser { Username = @"Host" },
+                    Category = RoomCategory.Normal,
+                    EndDate = DateTimeOffset.Now.AddMinutes(-1)
+                });
+            });
+
+            AddStep("push screen", () => LoadScreen(roomScreen = new PlaylistsRoomSubScreen(room)));
+            AddUntilStep("wait for screen load", () => roomScreen.IsCurrentScreen());
+            AddAssert("status is still ended", () => roomScreen.Room.Status, Is.TypeOf<RoomStatusEnded>);
+        }
+    }
+}

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

@@ -73,10 +73,10 @@ namespace osu.Game.Tests.Visual.UserInterface
             });
         });
 
-        [TestCase(BeatmapAttribute.CircleSize, "Circle Size: 1.00")]
+        [TestCase(BeatmapAttribute.CircleSize, "Circle Size: 1")]
-        [TestCase(BeatmapAttribute.HPDrain, "HP Drain: 2.00")]
+        [TestCase(BeatmapAttribute.HPDrain, "HP Drain: 2")]
-        [TestCase(BeatmapAttribute.Accuracy, "Accuracy: 3.00")]
+        [TestCase(BeatmapAttribute.Accuracy, "Accuracy: 3")]
-        [TestCase(BeatmapAttribute.ApproachRate, "Approach Rate: 4.00")]
+        [TestCase(BeatmapAttribute.ApproachRate, "Approach Rate: 4")]
         [TestCase(BeatmapAttribute.Title, "Title: _Title")]
         [TestCase(BeatmapAttribute.Artist, "Artist: _Artist")]
         [TestCase(BeatmapAttribute.Creator, "Creator: _Creator")]
@@ -121,15 +121,15 @@ namespace osu.Game.Tests.Visual.UserInterface
                     Difficulty =
                     {
                         ApproachRate = 10,
-                        CircleSize = 9
+                        CircleSize = 9.5f
                     }
                 }
             }));
 
-            test(BeatmapAttribute.BPM, new OsuModDoubleTime(), "BPM: 100.00", "BPM: 150.00");
+            test(BeatmapAttribute.BPM, new OsuModDoubleTime(), "BPM: 100", "BPM: 150");
             test(BeatmapAttribute.Length, new OsuModDoubleTime(), "Length: 00:30", "Length: 00:20");
-            test(BeatmapAttribute.ApproachRate, new OsuModDoubleTime(), "Approach Rate: 10.00", "Approach Rate: 11.00");
+            test(BeatmapAttribute.ApproachRate, new OsuModDoubleTime(), "Approach Rate: 10", "Approach Rate: 11");
-            test(BeatmapAttribute.CircleSize, new OsuModHardRock(), "Circle Size: 9.00", "Circle Size: 10.00");
+            test(BeatmapAttribute.CircleSize, new OsuModHardRock(), "Circle Size: 9.5", "Circle Size: 10");
 
             void test(BeatmapAttribute attribute, Mod mod, string before, string after)
             {

osu.Game/Configuration/OsuConfigManager.cs

@@ -54,7 +54,7 @@ namespace osu.Game.Configuration
             SetDefault(OsuSetting.ModSelectHotkeyStyle, ModSelectHotkeyStyle.Sequential);
             SetDefault(OsuSetting.ModSelectTextSearchStartsActive, true);
 
-            SetDefault(OsuSetting.ChatDisplayHeight, ChatOverlay.DEFAULT_HEIGHT, 0.2f, 1f);
+            SetDefault(OsuSetting.ChatDisplayHeight, ChatOverlay.DEFAULT_HEIGHT, 0.2f, 1f, 0.01f);
 
             SetDefault(OsuSetting.BeatmapListingCardSize, BeatmapCardSize.Normal);
 
@@ -132,7 +132,7 @@ namespace osu.Game.Configuration
             SetDefault(OsuSetting.Prefer24HourTime, !CultureInfoHelper.SystemCulture.DateTimeFormat.ShortTimePattern.Contains(@"tt"));
 
             // Gameplay
-            SetDefault(OsuSetting.PositionalHitsoundsLevel, 0.2f, 0, 1);
+            SetDefault(OsuSetting.PositionalHitsoundsLevel, 0.2f, 0, 1, 0.01f);
             SetDefault(OsuSetting.DimLevel, 0.7, 0, 1, 0.01);
             SetDefault(OsuSetting.BlurLevel, 0, 0, 1, 0.01);
             SetDefault(OsuSetting.LightenDuringBreaks, true);
@@ -169,13 +169,13 @@ namespace osu.Game.Configuration
 
             SetDefault(OsuSetting.Scaling, ScalingMode.Off);
             SetDefault(OsuSetting.SafeAreaConsiderations, true);
-            SetDefault(OsuSetting.ScalingBackgroundDim, 0.9f, 0.5f, 1f);
+            SetDefault(OsuSetting.ScalingBackgroundDim, 0.9f, 0.5f, 1f, 0.01f);
 
-            SetDefault(OsuSetting.ScalingSizeX, 0.8f, 0.2f, 1f);
+            SetDefault(OsuSetting.ScalingSizeX, 0.8f, 0.2f, 1f, 0.01f);
-            SetDefault(OsuSetting.ScalingSizeY, 0.8f, 0.2f, 1f);
+            SetDefault(OsuSetting.ScalingSizeY, 0.8f, 0.2f, 1f, 0.01f);
 
-            SetDefault(OsuSetting.ScalingPositionX, 0.5f, 0f, 1f);
+            SetDefault(OsuSetting.ScalingPositionX, 0.5f, 0f, 1f, 0.01f);
-            SetDefault(OsuSetting.ScalingPositionY, 0.5f, 0f, 1f);
+            SetDefault(OsuSetting.ScalingPositionY, 0.5f, 0f, 1f, 0.01f);
 
             SetDefault(OsuSetting.UIScale, 1f, 0.8f, 1.6f, 0.01f);
 

osu.Game/Online/Rooms/GetRoomsRequest.cs

@@ -1,12 +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.
 
-using System;
 using System.Collections.Generic;
 using osu.Framework.IO.Network;
 using osu.Game.Extensions;
 using osu.Game.Online.API;
-using osu.Game.Online.Rooms.RoomStatuses;
 using osu.Game.Screens.OnlinePlay.Lounge.Components;
 
 namespace osu.Game.Online.Rooms
@@ -35,25 +33,6 @@ namespace osu.Game.Online.Rooms
             return req;
         }
 
-        protected override void PostProcess()
-        {
-            base.PostProcess();
-
-            if (Response != null)
-            {
-                // API doesn't populate status so let's do it here.
-                foreach (var room in Response)
-                {
-                    if (room.EndDate != null && DateTimeOffset.Now >= room.EndDate)
-                        room.Status = new RoomStatusEnded();
-                    else if (room.HasPassword)
-                        room.Status = new RoomStatusOpenPrivate();
-                    else
-                        room.Status = new RoomStatusOpen();
-                }
-            }
-        }
-
         protected override string Target => "rooms";
     }
 }

osu.Game/Online/Rooms/Room.cs

@@ -6,6 +6,7 @@ using System.Collections.Generic;
 using System.ComponentModel;
 using System.Linq;
 using System.Runtime.CompilerServices;
+using System.Runtime.Serialization;
 using Newtonsoft.Json;
 using osu.Game.IO.Serialization.Converters;
 using osu.Game.Online.API.Requests.Responses;
@@ -264,6 +265,18 @@ namespace osu.Game.Online.Rooms
             set => SetField(ref availability, value);
         }
 
+        [OnDeserialized]
+        private void onDeserialised(StreamingContext context)
+        {
+            // API doesn't populate status so let's do it here.
+            if (EndDate != null && DateTimeOffset.Now >= EndDate)
+                Status = new RoomStatusEnded();
+            else if (HasPassword)
+                Status = new RoomStatusOpenPrivate();
+            else
+                Status = new RoomStatusOpen();
+        }
+
         [JsonProperty("id")]
         private long? roomId;
 

osu.Game/Rulesets/Edit/ComposerDistanceSnapProvider.cs

@@ -163,7 +163,7 @@ namespace osu.Game.Rulesets.Edit
             return (lastBefore, firstAfter);
         }
 
-        protected abstract double ReadCurrentDistanceSnap(HitObject before, HitObject after);
+        public abstract double ReadCurrentDistanceSnap(HitObject before, HitObject after);
 
         protected override void Update()
         {

osu.Game/Screens/OnlinePlay/Components/ListingPollingComponent.cs

@@ -18,7 +18,7 @@ namespace osu.Game.Screens.OnlinePlay.Components
         public IBindable<bool> InitialRoomsReceived => initialRoomsReceived;
         private readonly Bindable<bool> initialRoomsReceived = new Bindable<bool>();
 
-        public readonly Bindable<FilterCriteria> Filter = new Bindable<FilterCriteria>();
+        public readonly Bindable<FilterCriteria?> Filter = new Bindable<FilterCriteria?>();
 
         [BackgroundDependencyLoader]
         private void load()

osu.Game/Screens/OnlinePlay/DrawableRoomPlaylist.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.Linq;
 using osu.Framework.Bindables;
@@ -26,22 +24,22 @@ namespace osu.Game.Screens.OnlinePlay
         /// The currently-selected item. Selection is visually represented with a border.
         /// May be updated by clicking playlist items if <see cref="AllowSelection"/> is <c>true</c>.
         /// </summary>
-        public readonly Bindable<PlaylistItem> SelectedItem = new Bindable<PlaylistItem>();
+        public readonly Bindable<PlaylistItem?> SelectedItem = new Bindable<PlaylistItem?>();
 
         /// <summary>
         /// Invoked when an item is requested to be deleted.
         /// </summary>
-        public Action<PlaylistItem> RequestDeletion;
+        public Action<PlaylistItem>? RequestDeletion;
 
         /// <summary>
         /// Invoked when an item requests its results to be shown.
         /// </summary>
-        public Action<PlaylistItem> RequestResults;
+        public Action<PlaylistItem>? RequestResults;
 
         /// <summary>
         /// Invoked when an item requests to be edited.
         /// </summary>
-        public Action<PlaylistItem> RequestEdit;
+        public Action<PlaylistItem>? RequestEdit;
 
         private bool allowReordering;
 
@@ -235,7 +233,7 @@ namespace osu.Game.Screens.OnlinePlay
         {
             var visibleItems = ListContainer.AsEnumerable().Where(r => r.IsPresent);
 
-            PlaylistItem item;
+            PlaylistItem? item;
 
             if (SelectedItem.Value == null)
                 item = visibleItems.FirstOrDefault()?.Model;

osu.Game/Screens/OnlinePlay/DrawableRoomPlaylistItem.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;
@@ -54,23 +52,23 @@ namespace osu.Game.Screens.OnlinePlay
         /// <summary>
         /// Invoked when this item requests to be deleted.
         /// </summary>
-        public Action<PlaylistItem> RequestDeletion;
+        public Action<PlaylistItem>? RequestDeletion;
 
         /// <summary>
         /// Invoked when this item requests its results to be shown.
         /// </summary>
-        public Action<PlaylistItem> RequestResults;
+        public Action<PlaylistItem>? RequestResults;
 
         /// <summary>
         /// Invoked when this item requests to be edited.
         /// </summary>
-        public Action<PlaylistItem> RequestEdit;
+        public Action<PlaylistItem>? RequestEdit;
 
         /// <summary>
         /// The currently-selected item, used to show a border around this item.
         /// May be updated by this item if <see cref="AllowSelection"/> is <c>true</c>.
         /// </summary>
-        public readonly Bindable<PlaylistItem> SelectedItem = new Bindable<PlaylistItem>();
+        public readonly Bindable<PlaylistItem?> SelectedItem = new Bindable<PlaylistItem?>();
 
         public readonly PlaylistItem Item;
 
@@ -79,48 +77,48 @@ namespace osu.Game.Screens.OnlinePlay
         private readonly DelayedLoadWrapper onScreenLoader = new DelayedLoadWrapper(Empty) { RelativeSizeAxes = Axes.Both };
         private readonly IBindable<bool> valid = new Bindable<bool>();
 
-        private IBeatmapInfo beatmap;
+        private IBeatmapInfo? beatmap;
-        private IRulesetInfo ruleset;
+        private IRulesetInfo? ruleset;
         private Mod[] requiredMods = Array.Empty<Mod>();
 
-        private Container borderContainer;
+        private Container? borderContainer;
-        private FillFlowContainer difficultyIconContainer;
+        private FillFlowContainer? difficultyIconContainer;
-        private LinkFlowContainer beatmapText;
+        private LinkFlowContainer? beatmapText;
-        private LinkFlowContainer authorText;
+        private LinkFlowContainer? authorText;
-        private ExplicitContentBeatmapBadge explicitContent;
+        private ExplicitContentBeatmapBadge? explicitContent;
-        private ModDisplay modDisplay;
+        private ModDisplay? modDisplay;
-        private FillFlowContainer buttonsFlow;
+        private FillFlowContainer? buttonsFlow;
-        private UpdateableAvatar ownerAvatar;
+        private UpdateableAvatar? ownerAvatar;
-        private Drawable showResultsButton;
+        private Drawable? showResultsButton;
-        private Drawable editButton;
+        private Drawable? editButton;
-        private Drawable removeButton;
+        private Drawable? removeButton;
-        private PanelBackground panelBackground;
+        private PanelBackground? panelBackground;
-        private FillFlowContainer mainFillFlow;
+        private FillFlowContainer? mainFillFlow;
-        private BeatmapCardThumbnail thumbnail;
+        private BeatmapCardThumbnail? thumbnail;
 
         [Resolved]
-        private RealmAccess realm { get; set; }
+        private RealmAccess realm { get; set; } = null!;
 
         [Resolved]
-        private RulesetStore rulesets { get; set; }
+        private RulesetStore rulesets { get; set; } = null!;
 
         [Resolved]
-        private BeatmapManager beatmaps { get; set; }
+        private BeatmapManager beatmaps { get; set; } = null!;
 
         [Resolved]
-        private OsuColour colours { get; set; }
+        private OsuColour colours { get; set; } = null!;
 
         [Resolved]
-        private UserLookupCache userLookupCache { get; set; }
+        private UserLookupCache userLookupCache { get; set; } = null!;
 
         [Resolved]
-        private BeatmapLookupCache beatmapLookupCache { get; set; }
+        private BeatmapLookupCache beatmapLookupCache { get; set; } = null!;
 
         [Resolved(CanBeNull = true)]
-        private BeatmapSetOverlay beatmapOverlay { get; set; }
+        private BeatmapSetOverlay? beatmapOverlay { get; set; }
 
         [Resolved(CanBeNull = true)]
-        private ManageCollectionsDialog manageCollectionsDialog { get; set; }
+        private ManageCollectionsDialog? manageCollectionsDialog { get; set; }
 
         public DrawableRoomPlaylistItem(PlaylistItem item)
             : base(item)
@@ -136,6 +134,7 @@ namespace osu.Game.Screens.OnlinePlay
         [BackgroundDependencyLoader]
         private void load()
         {
+            if (borderContainer != null)
                 borderContainer.BorderColour = colours.Yellow;
 
             ruleset = rulesets.GetRuleset(Item.RulesetID);
@@ -163,6 +162,7 @@ namespace osu.Game.Screens.OnlinePlay
                     return;
                 }
 
+                if (borderContainer != null)
                     borderContainer.BorderThickness = IsSelectedItem ? border_thickness : 0;
             }, true);
 
@@ -177,7 +177,11 @@ namespace osu.Game.Screens.OnlinePlay
                         if (showItemOwner)
                         {
                             var foundUser = await userLookupCache.GetUserAsync(Item.OwnerID).ConfigureAwait(false);
-                            Schedule(() => ownerAvatar.User = foundUser);
+                            Schedule(() =>
+                            {
+                                if (ownerAvatar != null)
+                                    ownerAvatar.User = foundUser;
+                            });
                         }
 
                         beatmap = await beatmapLookupCache.GetBeatmapAsync(Item.Beatmap.OnlineID).ConfigureAwait(false);
@@ -277,13 +281,18 @@ namespace osu.Game.Screens.OnlinePlay
         }
 
         private void refresh()
+        {
+            if (borderContainer != null)
             {
                 if (!valid.Value)
                 {
                     borderContainer.BorderThickness = border_thickness;
                     borderContainer.BorderColour = colours.Red;
                 }
+            }
 
+            if (difficultyIconContainer != null)
+            {
                 if (beatmap != null)
                 {
                     difficultyIconContainer.Children = new Drawable[]
@@ -309,9 +318,13 @@ namespace osu.Game.Screens.OnlinePlay
                 }
                 else
                     difficultyIconContainer.Clear();
+            }
 
+            if (panelBackground != null)
                 panelBackground.Beatmap.Value = beatmap;
 
+            if (beatmapText != null)
+            {
                 beatmapText.Clear();
 
                 if (beatmap != null)
@@ -325,7 +338,10 @@ namespace osu.Game.Screens.OnlinePlay
                             text.Truncate = true;
                         });
                 }
+            }
 
+            if (authorText != null)
+            {
                 authorText.Clear();
 
                 if (!string.IsNullOrEmpty(beatmap?.Metadata.Author.Username))
@@ -333,14 +349,22 @@ namespace osu.Game.Screens.OnlinePlay
                     authorText.AddText("mapped by ");
                     authorText.AddUserLink(beatmap.Metadata.Author);
                 }
+            }
 
+            if (explicitContent != null)
+            {
                 bool hasExplicitContent = (beatmap?.BeatmapSet as IBeatmapSetOnlineInfo)?.HasExplicitContent == true;
                 explicitContent.Alpha = hasExplicitContent ? 1 : 0;
+            }
 
+            if (modDisplay != null)
                 modDisplay.Current.Value = requiredMods.ToArray();
 
+            if (buttonsFlow != null)
+            {
                 buttonsFlow.Clear();
                 buttonsFlow.ChildrenEnumerable = createButtons();
+            }
 
             difficultyIconContainer.FadeInFromZero(500, Easing.OutQuint);
             mainFillFlow.FadeInFromZero(500, Easing.OutQuint);
@@ -601,7 +625,7 @@ namespace osu.Game.Screens.OnlinePlay
             private readonly IBeatmapInfo beatmap;
 
             [Resolved]
-            private BeatmapManager beatmapManager { get; set; }
+            private BeatmapManager beatmapManager { get; set; } = null!;
 
             // required for download tracking, as this button hides itself. can probably be removed with a bit of consideration.
             public override bool IsPresent => true;
@@ -656,7 +680,7 @@ namespace osu.Game.Screens.OnlinePlay
         // For now, this is the same implementation as in PanelBackground, but supports a beatmap info rather than a working beatmap
         private partial class PanelBackground : Container // todo: should be a buffered container (https://github.com/ppy/osu-framework/issues/3222)
         {
-            public readonly Bindable<IBeatmapInfo> Beatmap = new Bindable<IBeatmapInfo>();
+            public readonly Bindable<IBeatmapInfo?> Beatmap = new Bindable<IBeatmapInfo?>();
 
             public PanelBackground()
             {

osu.Game/Screens/OnlinePlay/Lounge/Components/FilterCriteria.cs

@@ -1,18 +1,16 @@
 // 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;
 
 namespace osu.Game.Screens.OnlinePlay.Lounge.Components
 {
     public class FilterCriteria
     {
-        public string SearchString;
+        public string SearchString = string.Empty;
         public RoomStatusFilter Status;
-        public string Category;
+        public string Category = string.Empty;
-        public RulesetInfo Ruleset;
+        public RulesetInfo? Ruleset;
         public RoomPermissionsFilter Permissions;
     }
 }

osu.Game/Screens/OnlinePlay/Lounge/LoungeSubScreen.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.Bindables;
 using osu.Framework.Extensions;
@@ -54,42 +51,42 @@ namespace osu.Game.Screens.OnlinePlay.Lounge
             AutoSizeAxes = Axes.Both
         };
 
-        protected ListingPollingComponent ListingPollingComponent { get; private set; }
+        protected ListingPollingComponent ListingPollingComponent { get; private set; } = null!;
 
-        protected readonly Bindable<Room> SelectedRoom = new Bindable<Room>();
+        protected readonly Bindable<Room?> SelectedRoom = new Bindable<Room?>();
 
         [Resolved]
-        private MusicController music { get; set; }
+        private MusicController music { get; set; } = null!;
 
         [Resolved(CanBeNull = true)]
-        private OngoingOperationTracker ongoingOperationTracker { get; set; }
+        private OngoingOperationTracker? ongoingOperationTracker { get; set; }
 
         [Resolved]
-        private IBindable<RulesetInfo> ruleset { get; set; }
+        private IBindable<RulesetInfo> ruleset { get; set; } = null!;
 
         [Resolved]
-        private IAPIProvider api { get; set; }
+        private IAPIProvider api { get; set; } = null!;
 
-        [CanBeNull]
+        [Resolved(CanBeNull = true)]
-        private IDisposable joiningRoomOperation { get; set; }
+        private IdleTracker? idleTracker { get; set; }
-
-        [CanBeNull]
-        private LeasedBindable<Room> selectionLease;
 
         [Resolved]
-        protected OsuConfigManager Config { get; private set; }
+        protected OsuConfigManager Config { get; private set; } = null!;
 
-        private readonly Bindable<FilterCriteria> filter = new Bindable<FilterCriteria>(new FilterCriteria());
+        private IDisposable? joiningRoomOperation { get; set; }
+        private LeasedBindable<Room?>? selectionLease;
+
+        private readonly Bindable<FilterCriteria?> filter = new Bindable<FilterCriteria?>();
         private readonly IBindable<bool> operationInProgress = new Bindable<bool>();
         private readonly IBindable<bool> isIdle = new BindableBool();
-        private PopoverContainer popoverContainer;
+        private PopoverContainer popoverContainer = null!;
-        private LoadingLayer loadingLayer;
+        private LoadingLayer loadingLayer = null!;
-        private RoomsContainer roomsContainer;
+        private RoomsContainer roomsContainer = null!;
-        private SearchTextBox searchTextBox;
+        private SearchTextBox searchTextBox = null!;
-        private Dropdown<RoomStatusFilter> statusDropdown;
+        private Dropdown<RoomStatusFilter> statusDropdown = null!;
 
         [BackgroundDependencyLoader(true)]
-        private void load([CanBeNull] IdleTracker idleTracker)
+        private void load()
         {
             const float controls_area_height = 25f;
 
@@ -208,7 +205,7 @@ namespace osu.Game.Screens.OnlinePlay.Lounge
 
         public void UpdateFilter() => Scheduler.AddOnce(updateFilter);
 
-        private ScheduledDelegate scheduledFilterUpdate;
+        private ScheduledDelegate? scheduledFilterUpdate;
 
         private void updateFilterDebounced()
         {
@@ -262,7 +259,7 @@ namespace osu.Game.Screens.OnlinePlay.Lounge
             if (SelectedRoom.Value?.RoomID == null)
                 SelectedRoom.Value = new Room();
 
-            music?.EnsurePlayingSomething();
+            music.EnsurePlayingSomething();
 
             onReturning();
         }
@@ -299,7 +296,7 @@ namespace osu.Game.Screens.OnlinePlay.Lounge
             popoverContainer.HidePopover();
         }
 
-        public virtual void Join(Room room, string password, Action<Room> onSuccess = null, Action<string> onFailure = null) => Schedule(() =>
+        public virtual void Join(Room room, string? password, Action<Room>? onSuccess = null, Action<string>? onFailure = null) => Schedule(() =>
         {
             if (joiningRoomOperation != null)
                 return;
@@ -364,7 +361,7 @@ namespace osu.Game.Screens.OnlinePlay.Lounge
         /// Push a room as a new subscreen.
         /// </summary>
         /// <param name="room">An optional template to use when creating the room.</param>
-        public void Open(Room room = null) => Schedule(() =>
+        public void Open(Room? room = null) => Schedule(() =>
         {
             // Handles the case where a room is clicked 3 times in quick succession
             if (!this.IsCurrentScreen())

osu.Game/Screens/OnlinePlay/Match/Components/MatchLeaderboardScore.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.Allocation;
 using osu.Framework.Graphics.Sprites;
@@ -17,7 +15,7 @@ namespace osu.Game.Screens.OnlinePlay.Match.Components
     {
         private readonly APIUserScoreAggregate score;
 
-        public override ScoreInfo TooltipContent => null; // match aggregate scores can't show statistics that the custom tooltip displays.
+        public override ScoreInfo? TooltipContent => null; // match aggregate scores can't show statistics that the custom tooltip displays.
 
         public MatchLeaderboardScore(APIUserScoreAggregate score, int? rank, bool isOnlineScope = true)
             : base(score.CreateScoreInfo(), rank, isOnlineScope)

osu.Game/Screens/OnlinePlay/Match/Components/MatchTypePicker.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.Audio;
 using osu.Framework.Audio.Sample;
@@ -26,7 +24,7 @@ namespace osu.Game.Screens.OnlinePlay.Match.Components
 
         protected override TabItem<MatchType> CreateTabItem(MatchType value) => new GameTypePickerItem(value);
 
-        protected override Dropdown<MatchType> CreateDropdown() => null;
+        protected override Dropdown<MatchType>? CreateDropdown() => null;
 
         public MatchTypePicker()
         {
@@ -41,7 +39,8 @@ namespace osu.Game.Screens.OnlinePlay.Match.Components
         {
             private const float transition_duration = 200;
 
-            private readonly CircularContainer hover, selection;
+            private readonly CircularContainer hover;
+            private readonly CircularContainer selection;
 
             public GameTypePickerItem(MatchType value)
                 : base(value)
@@ -84,7 +83,7 @@ namespace osu.Game.Screens.OnlinePlay.Match.Components
                 };
             }
 
-            private Sample selectSample;
+            private Sample selectSample = null!;
 
             [BackgroundDependencyLoader]
             private void load(OsuColour colours, AudioManager audio)

osu.Game/Screens/OnlinePlay/Match/Components/RoomAvailabilityPicker.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;
 using osu.Framework.Extensions.Color4Extensions;
@@ -22,7 +20,7 @@ namespace osu.Game.Screens.OnlinePlay.Match.Components
     public partial class RoomAvailabilityPicker : DisableableTabControl<RoomAvailability>
     {
         protected override TabItem<RoomAvailability> CreateTabItem(RoomAvailability value) => new RoomAvailabilityPickerItem(value);
-        protected override Dropdown<RoomAvailability> CreateDropdown() => null;
+        protected override Dropdown<RoomAvailability>? CreateDropdown() => null;
 
         public RoomAvailabilityPicker()
         {

osu.Game/Screens/OnlinePlay/Match/RoomModSelectOverlay.cs

@@ -16,7 +16,7 @@ namespace osu.Game.Screens.OnlinePlay.Match
 {
     public partial class RoomModSelectOverlay : UserModSelectOverlay
     {
-        public Bindable<PlaylistItem> SelectedItem { get; } = new Bindable<PlaylistItem>();
+        public Bindable<PlaylistItem?> SelectedItem { get; } = new Bindable<PlaylistItem?>();
 
         [Resolved]
         private RulesetStore rulesets { get; set; } = null!;

osu.Game/Screens/OnlinePlay/Match/RoomSubScreen.cs

@@ -1,14 +1,11 @@
 // 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.ComponentModel;
 using System.Diagnostics;
 using System.Linq;
-using JetBrains.Annotations;
 using osu.Framework.Allocation;
 using osu.Framework.Audio;
 using osu.Framework.Audio.Sample;
@@ -37,7 +34,7 @@ namespace osu.Game.Screens.OnlinePlay.Match
     [Cached(typeof(IPreviewTrackOwner))]
     public abstract partial class RoomSubScreen : OnlinePlaySubScreen, IPreviewTrackOwner
     {
-        public readonly Bindable<PlaylistItem> SelectedItem = new Bindable<PlaylistItem>();
+        public readonly Bindable<PlaylistItem?> SelectedItem = new Bindable<PlaylistItem?>();
 
         public override bool? ApplyModTrackAdjustments => true;
 
@@ -52,9 +49,9 @@ namespace osu.Game.Screens.OnlinePlay.Match
         /// A container that provides controls for selection of user mods.
         /// This will be shown/hidden automatically when applicable.
         /// </summary>
-        protected Drawable UserModsSection;
+        protected Drawable? UserModsSection;
 
-        private Sample sampleStart;
+        private Sample? sampleStart;
 
         /// <summary>
         /// Any mods applied by/to the local user.
@@ -62,28 +59,28 @@ namespace osu.Game.Screens.OnlinePlay.Match
         protected readonly Bindable<IReadOnlyList<Mod>> UserMods = new Bindable<IReadOnlyList<Mod>>(Array.Empty<Mod>());
 
         [Resolved(CanBeNull = true)]
-        private IOverlayManager overlayManager { get; set; }
+        private IOverlayManager? overlayManager { get; set; }
 
         [Resolved]
-        private MusicController music { get; set; }
+        private MusicController music { get; set; } = null!;
 
         [Resolved]
-        private BeatmapManager beatmapManager { get; set; }
+        private BeatmapManager beatmapManager { get; set; } = null!;
 
         [Resolved]
-        protected RulesetStore Rulesets { get; private set; }
+        protected RulesetStore Rulesets { get; private set; } = null!;
 
         [Resolved]
         private IAPIProvider api { get; set; } = null!;
 
         [Resolved(canBeNull: true)]
-        protected OnlinePlayScreen ParentScreen { get; private set; }
+        protected OnlinePlayScreen? ParentScreen { get; private set; }
 
         [Resolved]
         private PreviewTrackManager previewTrackManager { get; set; } = null!;
 
         [Resolved(canBeNull: true)]
-        private IDialogOverlay dialogOverlay { get; set; }
+        private IDialogOverlay? dialogOverlay { get; set; }
 
         [Cached]
         private readonly OnlinePlayBeatmapAvailabilityTracker beatmapAvailabilityTracker = new OnlinePlayBeatmapAvailabilityTracker();
@@ -93,13 +90,11 @@ namespace osu.Game.Screens.OnlinePlay.Match
         public readonly Room Room;
         private readonly bool allowEdit;
 
-        internal ModSelectOverlay UserModsSelectOverlay { get; private set; }
+        internal ModSelectOverlay UserModsSelectOverlay { get; private set; } = null!;
 
-        [CanBeNull]
+        private IDisposable? userModsSelectOverlayRegistration;
-        private IDisposable userModsSelectOverlayRegistration;
+        private RoomSettingsOverlay settingsOverlay = null!;
-
+        private Drawable mainContent = null!;
-        private RoomSettingsOverlay settingsOverlay;
-        private Drawable mainContent;
 
         /// <summary>
         /// Creates a new <see cref="RoomSubScreen"/>.
@@ -265,7 +260,7 @@ namespace osu.Game.Screens.OnlinePlay.Match
             updateSetupState();
         }
 
-        private void onRoomPropertyChanged(object sender, PropertyChangedEventArgs e)
+        private void onRoomPropertyChanged(object? sender, PropertyChangedEventArgs e)
         {
             if (e.PropertyName == nameof(Room.RoomID))
                 updateSetupState();
@@ -388,6 +383,9 @@ namespace osu.Game.Screens.OnlinePlay.Match
 
         protected void StartPlay()
         {
+            if (SelectedItem.Value == null)
+                return;
+
             // User may be at song select or otherwise when the host starts gameplay.
             // Ensure that they first return to this screen, else global bindables (beatmap etc.) may be in a bad state.
             if (!this.IsCurrentScreen())
@@ -401,29 +399,28 @@ namespace osu.Game.Screens.OnlinePlay.Match
             sampleStart?.Play();
 
             // fallback is to allow this class to operate when there is no parent OnlineScreen (testing purposes).
-            var targetScreen = (Screen)ParentScreen ?? this;
+            var targetScreen = (Screen?)ParentScreen ?? this;
 
-            targetScreen.Push(CreateGameplayScreen());
+            targetScreen.Push(CreateGameplayScreen(SelectedItem.Value));
         }
 
         /// <summary>
         /// Creates the gameplay screen to be entered.
         /// </summary>
+        /// <param name="selectedItem">The playlist item about to be played.</param>
         /// <returns>The screen to enter.</returns>
-        protected abstract Screen CreateGameplayScreen();
+        protected abstract Screen CreateGameplayScreen(PlaylistItem selectedItem);
 
         private void selectedItemChanged()
         {
             updateWorkingBeatmap();
 
-            var selected = SelectedItem.Value;
+            if (SelectedItem.Value is not PlaylistItem selected)
-
-            if (selected == null)
                 return;
 
-            var rulesetInstance = Rulesets.GetRuleset(SelectedItem.Value.RulesetID)?.CreateInstance();
+            var rulesetInstance = Rulesets.GetRuleset(selected.RulesetID)?.CreateInstance();
             Debug.Assert(rulesetInstance != null);
-            var allowedMods = SelectedItem.Value.AllowedMods.Select(m => m.ToMod(rulesetInstance));
+            var allowedMods = selected.AllowedMods.Select(m => m.ToMod(rulesetInstance));
 
             // Remove any user mods that are no longer allowed.
             UserMods.Value = UserMods.Value.Where(m => allowedMods.Any(a => m.GetType() == a.GetType())).ToList();
@@ -494,7 +491,7 @@ namespace osu.Game.Screens.OnlinePlay.Match
             cancelTrackLooping();
         }
 
-        private void applyLoopingToTrack(ValueChangedEvent<WorkingBeatmap> _ = null)
+        private void applyLoopingToTrack(ValueChangedEvent<WorkingBeatmap>? _ = null)
         {
             if (!this.IsCurrentScreen())
                 return;
@@ -503,8 +500,8 @@ namespace osu.Game.Screens.OnlinePlay.Match
 
             if (track != null)
             {
-                Beatmap.Value.PrepareTrackForPreview(true);
+                Beatmap.Value!.PrepareTrackForPreview(true);
-                music?.EnsurePlayingSomething();
+                music.EnsurePlayingSomething();
             }
         }
 

osu.Game/Screens/OnlinePlay/Match/UserModSelectButton.cs

@@ -1,7 +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.Bindings;
 using osu.Framework.Input.Events;
 using osu.Game.Input.Bindings;

osu.Game/Screens/OnlinePlay/Multiplayer/CreateMultiplayerMatchButton.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.Game.Online.Multiplayer;
@@ -12,14 +10,14 @@ namespace osu.Game.Screens.OnlinePlay.Multiplayer
 {
     public partial class CreateMultiplayerMatchButton : CreateRoomButton
     {
-        private IBindable<bool> isConnected;
+        private IBindable<bool> isConnected = null!;
-        private IBindable<bool> operationInProgress;
+        private IBindable<bool> operationInProgress = null!;
 
         [Resolved]
-        private MultiplayerClient multiplayerClient { get; set; }
+        private MultiplayerClient multiplayerClient { get; set; } = null!;
 
         [Resolved]
-        private OngoingOperationTracker ongoingOperationTracker { get; set; }
+        private OngoingOperationTracker ongoingOperationTracker { get; set; } = null!;
 
         [BackgroundDependencyLoader]
         private void load()

osu.Game/Screens/OnlinePlay/Multiplayer/GameplayChatDisplay.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;
@@ -20,8 +17,7 @@ namespace osu.Game.Screens.OnlinePlay.Multiplayer
     public partial class GameplayChatDisplay : MatchChatDisplay, IKeyBindingHandler<GlobalAction>
     {
         [Resolved(CanBeNull = true)]
-        [CanBeNull]
+        private ILocalUserPlayInfo? localUserInfo { get; set; }
-        private ILocalUserPlayInfo localUserInfo { get; set; }
 
         private readonly IBindable<LocalUserPlayingState> localUserPlaying = new Bindable<LocalUserPlayingState>();
 

osu.Game/Screens/OnlinePlay/Multiplayer/Match/MultiplayerCountdownButton.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.Linq;
 using Humanizer;
@@ -33,15 +31,14 @@ namespace osu.Game.Screens.OnlinePlay.Multiplayer.Match
             TimeSpan.FromMinutes(2)
         };
 
-        public new Action<TimeSpan> Action;
+        public new required Action<TimeSpan> Action;
-
+        public required Action CancelAction;
-        public Action CancelAction;
 
         [Resolved]
-        private MultiplayerClient multiplayerClient { get; set; }
+        private MultiplayerClient multiplayerClient { get; set; } = null!;
 
         [Resolved]
-        private OsuColour colours { get; set; }
+        private OsuColour colours { get; set; } = null!;
 
         private readonly Drawable background;
 

osu.Game/Screens/OnlinePlay/Multiplayer/Match/MultiplayerReadyButton.cs

@@ -1,14 +1,13 @@
 // 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.Audio;
 using osu.Framework.Audio.Sample;
+using osu.Framework.Extensions.ObjectExtensions;
 using osu.Framework.Localisation;
 using osu.Framework.Threading;
 using osu.Game.Graphics;
@@ -20,17 +19,16 @@ namespace osu.Game.Screens.OnlinePlay.Multiplayer.Match
     public partial class MultiplayerReadyButton : ReadyButton
     {
         [Resolved]
-        private MultiplayerClient multiplayerClient { get; set; }
+        private MultiplayerClient multiplayerClient { get; set; } = null!;
 
         [Resolved]
-        private OsuColour colours { get; set; }
+        private OsuColour colours { get; set; } = null!;
 
-        [CanBeNull]
+        private MultiplayerRoom? room => multiplayerClient.Room;
-        private MultiplayerRoom room => multiplayerClient.Room;
 
-        private Sample countdownTickSample;
+        private Sample? countdownTickSample;
-        private Sample countdownWarnSample;
+        private Sample? countdownWarnSample;
-        private Sample countdownWarnFinalSample;
+        private Sample? countdownWarnFinalSample;
 
         [BackgroundDependencyLoader]
         private void load(AudioManager audio)
@@ -48,13 +46,13 @@ namespace osu.Game.Screens.OnlinePlay.Multiplayer.Match
             onRoomUpdated();
         }
 
-        private MultiplayerCountdown countdown;
+        private MultiplayerCountdown? countdown;
         private double countdownChangeTime;
-        private ScheduledDelegate countdownUpdateDelegate;
+        private ScheduledDelegate? countdownUpdateDelegate;
 
         private void onRoomUpdated() => Scheduler.AddOnce(() =>
         {
-            MultiplayerCountdown newCountdown = room?.ActiveCountdowns.SingleOrDefault(c => c is MatchStartCountdown);
+            MultiplayerCountdown? newCountdown = room?.ActiveCountdowns.SingleOrDefault(c => c is MatchStartCountdown);
 
             if (newCountdown != countdown)
             {
@@ -171,6 +169,8 @@ namespace osu.Game.Screens.OnlinePlay.Multiplayer.Match
         {
             get
             {
+                Debug.Assert(countdown != null);
+
                 double timeElapsed = Time.Current - countdownChangeTime;
                 TimeSpan remaining;
 
@@ -224,7 +224,7 @@ namespace osu.Game.Screens.OnlinePlay.Multiplayer.Match
         {
             base.Dispose(isDisposing);
 
-            if (multiplayerClient != null)
+            if (multiplayerClient.IsNotNull())
                 multiplayerClient.RoomUpdated -= onRoomUpdated;
         }
 

osu.Game/Screens/OnlinePlay/Multiplayer/Match/MultiplayerSpectateButton.cs

@@ -58,7 +58,7 @@ namespace osu.Game.Screens.OnlinePlay.Multiplayer.Match
 
             client.ToggleSpectate().ContinueWith(_ => endOperation());
 
-            void endOperation() => clickOperation?.Dispose();
+            void endOperation() => clickOperation.Dispose();
         }
 
         [BackgroundDependencyLoader]

osu.Game/Screens/OnlinePlay/Multiplayer/MultiplayerLoungeSubScreen.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 System.Threading.Tasks;
@@ -27,12 +25,12 @@ namespace osu.Game.Screens.OnlinePlay.Multiplayer
     public partial class MultiplayerLoungeSubScreen : LoungeSubScreen
     {
         [Resolved]
-        private IAPIProvider api { get; set; }
+        private IAPIProvider api { get; set; } = null!;
 
         [Resolved]
-        private MultiplayerClient client { get; set; }
+        private MultiplayerClient client { get; set; } = null!;
 
-        private Dropdown<RoomPermissionsFilter> roomAccessTypeDropdown;
+        private Dropdown<RoomPermissionsFilter> roomAccessTypeDropdown = null!;
 
         public override void OnResuming(ScreenTransitionEvent e)
         {
@@ -83,7 +81,7 @@ namespace osu.Game.Screens.OnlinePlay.Multiplayer
 
         protected override void OpenNewRoom(Room room)
         {
-            if (client?.IsConnected.Value != true)
+            if (!client.IsConnected.Value)
             {
                 Logger.Log("Not currently connected to the multiplayer server.", LoggingTarget.Runtime, LogLevel.Important);
                 return;
@@ -95,7 +93,7 @@ namespace osu.Game.Screens.OnlinePlay.Multiplayer
         private partial class MultiplayerListingPollingComponent : ListingPollingComponent
         {
             [Resolved]
-            private MultiplayerClient client { get; set; }
+            private MultiplayerClient client { get; set; } = null!;
 
             private readonly IBindable<bool> isConnected = new Bindable<bool>();
 

osu.Game/Screens/OnlinePlay/Multiplayer/MultiplayerMatchSubScreen.cs

@@ -401,7 +401,7 @@ namespace osu.Game.Screens.OnlinePlay.Multiplayer
             StartPlay();
         }
 
-        protected override Screen CreateGameplayScreen()
+        protected override Screen CreateGameplayScreen(PlaylistItem selectedItem)
         {
             Debug.Assert(client.LocalUser != null);
             Debug.Assert(client.Room != null);
@@ -415,7 +415,7 @@ namespace osu.Game.Screens.OnlinePlay.Multiplayer
                     return new MultiSpectatorScreen(Room, users.Take(PlayerGrid.MAX_PLAYERS).ToArray());
 
                 default:
-                    return new MultiplayerPlayerLoader(() => new MultiplayerPlayer(Room, SelectedItem.Value, users));
+                    return new MultiplayerPlayerLoader(() => new MultiplayerPlayer(Room, selectedItem, users));
             }
         }
 

osu.Game/Screens/OnlinePlay/Multiplayer/MultiplayerPlayerLoader.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.Threading.Tasks;
 using osu.Framework.Allocation;
@@ -18,9 +16,9 @@ namespace osu.Game.Screens.OnlinePlay.Multiplayer
         public bool GameplayPassed => player?.GameplayState.HasPassed == true;
 
         [Resolved]
-        private MultiplayerClient multiplayerClient { get; set; }
+        private MultiplayerClient multiplayerClient { get; set; } = null!;
 
-        private Player player;
+        private Player? player;
 
         public MultiplayerPlayerLoader(Func<Player> createPlayer)
             : base(createPlayer)
@@ -45,7 +43,7 @@ namespace osu.Game.Screens.OnlinePlay.Multiplayer
                              .ContinueWith(task => failAndBail(task.Exception?.Message ?? "Server error"), TaskContinuationOptions.NotOnRanToCompletion);
         }
 
-        private void failAndBail(string message = null)
+        private void failAndBail(string? message = null)
         {
             if (!string.IsNullOrEmpty(message))
                 Logger.Log(message, LoggingTarget.Runtime, LogLevel.Important);

osu.Game/Screens/OnlinePlay/OngoingOperationTracker.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.Bindables;
 using osu.Framework.Graphics;
@@ -22,7 +20,7 @@ namespace osu.Game.Screens.OnlinePlay
 
         private readonly Bindable<bool> inProgress = new BindableBool();
 
-        private LeasedBindable<bool> leasedInProgress;
+        private LeasedBindable<bool>? leasedInProgress;
 
         public OngoingOperationTracker()
         {

osu.Game/Screens/OnlinePlay/OnlinePlayScreen.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.Diagnostics;
 using osu.Framework.Allocation;
 using osu.Framework.Bindables;
@@ -27,16 +25,16 @@ namespace osu.Game.Screens.OnlinePlay
 
         public IScreen CurrentSubScreen => screenStack.CurrentScreen;
 
-        public override bool CursorVisible => (screenStack?.CurrentScreen as IOnlinePlaySubScreen)?.CursorVisible ?? true;
+        public override bool CursorVisible => (screenStack.CurrentScreen as IOnlinePlaySubScreen)?.CursorVisible ?? true;
 
         // this is required due to PlayerLoader eventually being pushed to the main stack
         // while leases may be taken out by a subscreen.
         public override bool DisallowExternalBeatmapRulesetChanges => true;
 
-        protected LoungeSubScreen Lounge { get; private set; }
+        protected LoungeSubScreen Lounge { get; private set; } = null!;
 
-        private OnlinePlayScreenWaveContainer waves;
+        private readonly ScreenStack screenStack = new OnlinePlaySubScreenStack { RelativeSizeAxes = Axes.Both };
-        private ScreenStack screenStack;
+        private OnlinePlayScreenWaveContainer waves = null!;
 
         [Cached(Type = typeof(IRoomManager))]
         protected RoomManager RoomManager { get; private set; }
@@ -45,7 +43,7 @@ namespace osu.Game.Screens.OnlinePlay
         private readonly OngoingOperationTracker ongoingOperationTracker = new OngoingOperationTracker();
 
         [Resolved]
-        protected IAPIProvider API { get; private set; }
+        protected IAPIProvider API { get; private set; } = null!;
 
         protected OnlinePlayScreen()
         {
@@ -67,7 +65,7 @@ namespace osu.Game.Screens.OnlinePlay
                 RelativeSizeAxes = Axes.Both,
                 Children = new Drawable[]
                 {
-                    screenStack = new OnlinePlaySubScreenStack { RelativeSizeAxes = Axes.Both },
+                    screenStack,
                     new Header(ScreenTitle, screenStack),
                     RoomManager,
                     ongoingOperationTracker,

osu.Game/Screens/OnlinePlay/Playlists/PlaylistsRoomSubScreen.cs

@@ -273,10 +273,13 @@ namespace osu.Game.Screens.OnlinePlay.Playlists
             Logger.Log($"Polling adjusted (selection: {selectionPollingComponent.TimeBetweenPolls.Value})");
         }
 
-        protected override Screen CreateGameplayScreen() => new PlayerLoader(() => new PlaylistsPlayer(Room, SelectedItem.Value)
+        protected override Screen CreateGameplayScreen(PlaylistItem selectedItem)
+        {
+            return new PlayerLoader(() => new PlaylistsPlayer(Room, selectedItem)
             {
                 Exited = () => leaderboard.RefetchScores()
             });
+        }
 
         protected override void Dispose(bool isDisposing)
         {

osu.Game/Screens/Play/BreakOverlay.cs

@@ -166,7 +166,7 @@ namespace osu.Game.Screens.Play
                 return;
 
             float timeBoxTargetWidth = (float)Math.Max(0, (remainingTimeForCurrentPeriod - timingPoint.BeatLength / currentPeriod.Value.Value.Duration));
-            remainingTimeBox.ResizeWidthTo(timeBoxTargetWidth, timingPoint.BeatLength * 2, Easing.OutQuint);
+            remainingTimeBox.ResizeWidthTo(timeBoxTargetWidth, timingPoint.BeatLength * 3.5, Easing.OutQuint);
         }
 
         private void updateDisplay(ValueChangedEvent<Period?> period)

osu.Game/Screens/Play/PlayerLoader.cs

@@ -122,7 +122,9 @@ namespace osu.Game.Screens.Play
             // not ready if the user is dragging a slider or otherwise.
             && (inputManager.DraggedDrawable == null || inputManager.DraggedDrawable is OsuLogo)
             // not ready if a focused overlay is visible, like settings.
-            && inputManager.FocusedDrawable == null;
+            && inputManager.FocusedDrawable is not OsuFocusedOverlayContainer
+            // or if a child of a focused overlay is focused, like settings' search textbox.
+            && inputManager.FocusedDrawable?.FindClosestParent<OsuFocusedOverlayContainer>() == null;
 
         private readonly Func<Player> createPlayer;
 

osu.Game/Screens/Play/SkipOverlay.cs

@@ -219,7 +219,7 @@ namespace osu.Game.Screens.Play
 
             float progress = (float)(gameplayClock.CurrentTime - displayTime) / (float)(fadeOutBeginTime - displayTime);
             float newWidth = 1 - Math.Clamp(progress, 0, 1);
-            remainingTimeBox.ResizeWidthTo(newWidth, timingPoint.BeatLength * 2, Easing.OutQuint);
+            remainingTimeBox.ResizeWidthTo(newWidth, timingPoint.BeatLength * 3.5, Easing.OutQuint);
         }
 
         public partial class FadeContainer : Container, IStateful<Visibility>

osu.Game/Screens/Ranking/Expanded/Accuracy/AccuracyCircle.cs

@@ -298,7 +298,7 @@ namespace osu.Game.Screens.Ranking.Expanded.Accuracy
                 {
                     foreach (var badge in badges)
                     {
-                        if (badge.Accuracy > score.Accuracy)
+                        if (badge.Rank > score.Rank)
                             continue;
 
                         using (BeginDelayedSequence(