Merge branch 'master' into beatmap-cancellation-token

Templates/Rulesets/ruleset-empty/osu.Game.Rulesets.EmptyFreeform/EmptyFreeformDifficultyCalculator.cs

@@ -13,7 +13,7 @@ namespace osu.Game.Rulesets.EmptyFreeform
 {
     public class EmptyFreeformDifficultyCalculator : DifficultyCalculator
     {
-        public EmptyFreeformDifficultyCalculator(Ruleset ruleset, WorkingBeatmap beatmap)
+        public EmptyFreeformDifficultyCalculator(IRulesetInfo ruleset, IWorkingBeatmap beatmap)
             : base(ruleset, beatmap)
         {
         }

Templates/Rulesets/ruleset-empty/osu.Game.Rulesets.EmptyFreeform/EmptyFreeformRuleset.cs

@@ -30,8 +30,8 @@ namespace osu.Game.Rulesets.EmptyFreeform
         public override IBeatmapConverter CreateBeatmapConverter(IBeatmap beatmap) =>
             new EmptyFreeformBeatmapConverter(beatmap, this);
 
-        public override DifficultyCalculator CreateDifficultyCalculator(WorkingBeatmap beatmap) =>
+        public override DifficultyCalculator CreateDifficultyCalculator(IWorkingBeatmap beatmap) =>
-            new EmptyFreeformDifficultyCalculator(this, beatmap);
+            new EmptyFreeformDifficultyCalculator(RulesetInfo, beatmap);
 
         public override IEnumerable<Mod> GetModsFor(ModType type)
         {

Templates/Rulesets/ruleset-example/osu.Game.Rulesets.Pippidon/PippidonDifficultyCalculator.cs

@@ -13,7 +13,7 @@ namespace osu.Game.Rulesets.Pippidon
 {
     public class PippidonDifficultyCalculator : DifficultyCalculator
     {
-        public PippidonDifficultyCalculator(Ruleset ruleset, WorkingBeatmap beatmap)
+        public PippidonDifficultyCalculator(IRulesetInfo ruleset, IWorkingBeatmap beatmap)
             : base(ruleset, beatmap)
         {
         }

Templates/Rulesets/ruleset-example/osu.Game.Rulesets.Pippidon/PippidonRuleset.cs

@@ -26,8 +26,8 @@ namespace osu.Game.Rulesets.Pippidon
         public override IBeatmapConverter CreateBeatmapConverter(IBeatmap beatmap) =>
             new PippidonBeatmapConverter(beatmap, this);
 
-        public override DifficultyCalculator CreateDifficultyCalculator(WorkingBeatmap beatmap) =>
+        public override DifficultyCalculator CreateDifficultyCalculator(IWorkingBeatmap beatmap) =>
-            new PippidonDifficultyCalculator(this, beatmap);
+            new PippidonDifficultyCalculator(RulesetInfo, beatmap);
 
         public override IEnumerable<Mod> GetModsFor(ModType type)
         {

Templates/Rulesets/ruleset-scrolling-empty/osu.Game.Rulesets.EmptyScrolling/EmptyScrollingDifficultyCalculator.cs

@@ -13,7 +13,7 @@ namespace osu.Game.Rulesets.EmptyScrolling
 {
     public class EmptyScrollingDifficultyCalculator : DifficultyCalculator
     {
-        public EmptyScrollingDifficultyCalculator(Ruleset ruleset, WorkingBeatmap beatmap)
+        public EmptyScrollingDifficultyCalculator(IRulesetInfo ruleset, IWorkingBeatmap beatmap)
             : base(ruleset, beatmap)
         {
         }

Templates/Rulesets/ruleset-scrolling-empty/osu.Game.Rulesets.EmptyScrolling/EmptyScrollingRuleset.cs

@@ -24,7 +24,7 @@ namespace osu.Game.Rulesets.EmptyScrolling
 
         public override IBeatmapConverter CreateBeatmapConverter(IBeatmap beatmap) => new EmptyScrollingBeatmapConverter(beatmap, this);
 
-        public override DifficultyCalculator CreateDifficultyCalculator(WorkingBeatmap beatmap) => new EmptyScrollingDifficultyCalculator(this, beatmap);
+        public override DifficultyCalculator CreateDifficultyCalculator(IWorkingBeatmap beatmap) => new EmptyScrollingDifficultyCalculator(RulesetInfo, beatmap);
 
         public override IEnumerable<Mod> GetModsFor(ModType type)
         {

Templates/Rulesets/ruleset-scrolling-example/osu.Game.Rulesets.Pippidon/PippidonDifficultyCalculator.cs

@@ -13,7 +13,7 @@ namespace osu.Game.Rulesets.Pippidon
 {
     public class PippidonDifficultyCalculator : DifficultyCalculator
     {
-        public PippidonDifficultyCalculator(Ruleset ruleset, WorkingBeatmap beatmap)
+        public PippidonDifficultyCalculator(IRulesetInfo ruleset, IWorkingBeatmap beatmap)
             : base(ruleset, beatmap)
         {
         }

Templates/Rulesets/ruleset-scrolling-example/osu.Game.Rulesets.Pippidon/PippidonRuleset.cs

@@ -24,7 +24,7 @@ namespace osu.Game.Rulesets.Pippidon
 
         public override IBeatmapConverter CreateBeatmapConverter(IBeatmap beatmap) => new PippidonBeatmapConverter(beatmap, this);
 
-        public override DifficultyCalculator CreateDifficultyCalculator(WorkingBeatmap beatmap) => new PippidonDifficultyCalculator(this, beatmap);
+        public override DifficultyCalculator CreateDifficultyCalculator(IWorkingBeatmap beatmap) => new PippidonDifficultyCalculator(RulesetInfo, beatmap);
 
         public override IEnumerable<Mod> GetModsFor(ModType type)
         {

osu.Desktop/OsuGameDesktop.cs

@@ -93,6 +93,11 @@ namespace osu.Desktop
 
         protected override UpdateManager CreateUpdateManager()
         {
+            string packageManaged = Environment.GetEnvironmentVariable("OSU_EXTERNAL_UPDATE_PROVIDER");
+
+            if (!string.IsNullOrEmpty(packageManaged))
+                return new NoActionUpdateManager();
+
             switch (RuntimeInfo.OS)
             {
                 case RuntimeInfo.Platform.Windows:

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

@@ -22,7 +22,7 @@ namespace osu.Game.Rulesets.Catch.Tests
         public void TestClockRateAdjusted(double expected, string name)
             => Test(expected, name, new CatchModDoubleTime());
 
-        protected override DifficultyCalculator CreateDifficultyCalculator(WorkingBeatmap beatmap) => new CatchDifficultyCalculator(new CatchRuleset(), beatmap);
+        protected override DifficultyCalculator CreateDifficultyCalculator(IWorkingBeatmap beatmap) => new CatchDifficultyCalculator(new CatchRuleset().RulesetInfo, beatmap);
 
         protected override Ruleset CreateRuleset() => new CatchRuleset();
     }

osu.Game.Rulesets.Catch/CatchRuleset.cs

@@ -178,7 +178,7 @@ namespace osu.Game.Rulesets.Catch
             return base.GetDisplayNameForHitResult(result);
         }
 
-        public override DifficultyCalculator CreateDifficultyCalculator(WorkingBeatmap beatmap) => new CatchDifficultyCalculator(this, beatmap);
+        public override DifficultyCalculator CreateDifficultyCalculator(IWorkingBeatmap beatmap) => new CatchDifficultyCalculator(RulesetInfo, beatmap);
 
         public override ISkin CreateLegacySkinProvider(ISkin skin, IBeatmap beatmap) => new CatchLegacySkinTransformer(skin);
 

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

@@ -23,7 +23,7 @@ namespace osu.Game.Rulesets.Catch.Difficulty
 
         private float halfCatcherWidth;
 
-        public CatchDifficultyCalculator(Ruleset ruleset, WorkingBeatmap beatmap)
+        public CatchDifficultyCalculator(IRulesetInfo ruleset, IWorkingBeatmap beatmap)
             : base(ruleset, beatmap)
         {
         }

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

@@ -22,7 +22,7 @@ namespace osu.Game.Rulesets.Mania.Tests
         public void TestClockRateAdjusted(double expected, string name)
             => Test(expected, name, new ManiaModDoubleTime());
 
-        protected override DifficultyCalculator CreateDifficultyCalculator(WorkingBeatmap beatmap) => new ManiaDifficultyCalculator(new ManiaRuleset(), beatmap);
+        protected override DifficultyCalculator CreateDifficultyCalculator(IWorkingBeatmap beatmap) => new ManiaDifficultyCalculator(new ManiaRuleset().RulesetInfo, beatmap);
 
         protected override Ruleset CreateRuleset() => new ManiaRuleset();
     }

osu.Game.Rulesets.Mania/Difficulty/ManiaDifficultyCalculator.cs

@@ -5,6 +5,7 @@ using System;
 using System.Collections.Generic;
 using System.Linq;
 using osu.Game.Beatmaps;
+using osu.Game.Extensions;
 using osu.Game.Rulesets.Difficulty;
 using osu.Game.Rulesets.Difficulty.Preprocessing;
 using osu.Game.Rulesets.Difficulty.Skills;
@@ -28,11 +29,11 @@ namespace osu.Game.Rulesets.Mania.Difficulty
         private readonly bool isForCurrentRuleset;
         private readonly double originalOverallDifficulty;
 
-        public ManiaDifficultyCalculator(Ruleset ruleset, WorkingBeatmap beatmap)
+        public ManiaDifficultyCalculator(IRulesetInfo ruleset, IWorkingBeatmap beatmap)
             : base(ruleset, beatmap)
         {
-            isForCurrentRuleset = beatmap.BeatmapInfo.Ruleset.Equals(ruleset.RulesetInfo);
+            isForCurrentRuleset = beatmap.BeatmapInfo.Ruleset.MatchesOnlineID(ruleset);
-            originalOverallDifficulty = beatmap.BeatmapInfo.BaseDifficulty.OverallDifficulty;
+            originalOverallDifficulty = beatmap.BeatmapInfo.Difficulty.OverallDifficulty;
         }
 
         protected override DifficultyAttributes CreateDifficultyAttributes(IBeatmap beatmap, Mod[] mods, Skill[] skills, double clockRate)

osu.Game.Rulesets.Mania/ManiaRuleset.cs

@@ -272,7 +272,7 @@ namespace osu.Game.Rulesets.Mania
 
         public override Drawable CreateIcon() => new SpriteIcon { Icon = OsuIcon.RulesetMania };
 
-        public override DifficultyCalculator CreateDifficultyCalculator(WorkingBeatmap beatmap) => new ManiaDifficultyCalculator(this, beatmap);
+        public override DifficultyCalculator CreateDifficultyCalculator(IWorkingBeatmap beatmap) => new ManiaDifficultyCalculator(RulesetInfo, beatmap);
 
         public int LegacyID => 3;
 

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

@@ -25,7 +25,7 @@ namespace osu.Game.Rulesets.Osu.Tests
         public void TestClockRateAdjusted(double expected, string name)
             => Test(expected, name, new OsuModDoubleTime());
 
-        protected override DifficultyCalculator CreateDifficultyCalculator(WorkingBeatmap beatmap) => new OsuDifficultyCalculator(new OsuRuleset(), beatmap);
+        protected override DifficultyCalculator CreateDifficultyCalculator(IWorkingBeatmap beatmap) => new OsuDifficultyCalculator(new OsuRuleset().RulesetInfo, beatmap);
 
         protected override Ruleset CreateRuleset() => new OsuRuleset();
     }

osu.Game.Rulesets.Osu/Difficulty/OsuDifficultyCalculator.cs

@@ -23,7 +23,7 @@ namespace osu.Game.Rulesets.Osu.Difficulty
         private const double difficulty_multiplier = 0.0675;
         private double hitWindowGreat;
 
-        public OsuDifficultyCalculator(Ruleset ruleset, WorkingBeatmap beatmap)
+        public OsuDifficultyCalculator(IRulesetInfo ruleset, IWorkingBeatmap beatmap)
             : base(ruleset, beatmap)
         {
         }

osu.Game.Rulesets.Osu/OsuRuleset.cs

@@ -208,7 +208,7 @@ namespace osu.Game.Rulesets.Osu
 
         public override Drawable CreateIcon() => new SpriteIcon { Icon = OsuIcon.RulesetOsu };
 
-        public override DifficultyCalculator CreateDifficultyCalculator(WorkingBeatmap beatmap) => new OsuDifficultyCalculator(this, beatmap);
+        public override DifficultyCalculator CreateDifficultyCalculator(IWorkingBeatmap beatmap) => new OsuDifficultyCalculator(RulesetInfo, beatmap);
 
         public override PerformanceCalculator CreatePerformanceCalculator(DifficultyAttributes attributes, ScoreInfo score) => new OsuPerformanceCalculator(this, attributes, score);
 

osu.Game.Rulesets.Taiko.Tests/TaikoDifficultyCalculatorTest.cs

@@ -24,7 +24,7 @@ namespace osu.Game.Rulesets.Taiko.Tests
         public void TestClockRateAdjusted(double expected, string name)
             => Test(expected, name, new TaikoModDoubleTime());
 
-        protected override DifficultyCalculator CreateDifficultyCalculator(WorkingBeatmap beatmap) => new TaikoDifficultyCalculator(new TaikoRuleset(), beatmap);
+        protected override DifficultyCalculator CreateDifficultyCalculator(IWorkingBeatmap beatmap) => new TaikoDifficultyCalculator(new TaikoRuleset().RulesetInfo, beatmap);
 
         protected override Ruleset CreateRuleset() => new TaikoRuleset();
     }

osu.Game.Rulesets.Taiko/Difficulty/TaikoDifficultyCalculator.cs

@@ -24,7 +24,7 @@ namespace osu.Game.Rulesets.Taiko.Difficulty
         private const double colour_skill_multiplier = 0.01;
         private const double stamina_skill_multiplier = 0.02;
 
-        public TaikoDifficultyCalculator(Ruleset ruleset, WorkingBeatmap beatmap)
+        public TaikoDifficultyCalculator(IRulesetInfo ruleset, IWorkingBeatmap beatmap)
             : base(ruleset, beatmap)
         {
         }

osu.Game.Rulesets.Taiko/TaikoRuleset.cs

@@ -168,7 +168,7 @@ namespace osu.Game.Rulesets.Taiko
 
         public override HitObjectComposer CreateHitObjectComposer() => new TaikoHitObjectComposer(this);
 
-        public override DifficultyCalculator CreateDifficultyCalculator(WorkingBeatmap beatmap) => new TaikoDifficultyCalculator(this, beatmap);
+        public override DifficultyCalculator CreateDifficultyCalculator(IWorkingBeatmap beatmap) => new TaikoDifficultyCalculator(RulesetInfo, beatmap);
 
         public override PerformanceCalculator CreatePerformanceCalculator(DifficultyAttributes attributes, ScoreInfo score) => new TaikoPerformanceCalculator(this, attributes, score);
 

osu.Game.Tests/Mods/ModDifficultyAdjustTest.cs

@@ -156,7 +156,7 @@ namespace osu.Game.Tests.Mods
                 throw new System.NotImplementedException();
             }
 
-            public override DifficultyCalculator CreateDifficultyCalculator(WorkingBeatmap beatmap)
+            public override DifficultyCalculator CreateDifficultyCalculator(IWorkingBeatmap beatmap)
             {
                 throw new System.NotImplementedException();
             }

osu.Game.Tests/NonVisual/BeatmapSetInfoEqualityTest.cs

@@ -3,6 +3,7 @@
 
 using NUnit.Framework;
 using osu.Game.Beatmaps;
+using osu.Game.Extensions;
 
 namespace osu.Game.Tests.NonVisual
 {
@@ -15,7 +16,8 @@ namespace osu.Game.Tests.NonVisual
             var ourInfo = new BeatmapSetInfo { OnlineID = 123 };
             var otherInfo = new BeatmapSetInfo { OnlineID = 123 };
 
-            Assert.AreEqual(ourInfo, otherInfo);
+            Assert.AreNotEqual(ourInfo, otherInfo);
+            Assert.IsTrue(ourInfo.MatchesOnlineID(otherInfo));
         }
 
         [Test]
@@ -33,7 +35,8 @@ namespace osu.Game.Tests.NonVisual
             var ourInfo = new BeatmapSetInfo { ID = 123, OnlineID = 12 };
             var otherInfo = new BeatmapSetInfo { OnlineID = 12 };
 
-            Assert.AreEqual(ourInfo, otherInfo);
+            Assert.AreNotEqual(ourInfo, otherInfo);
+            Assert.IsTrue(ourInfo.MatchesOnlineID(otherInfo));
         }
 
         [Test]

osu.Game.Tests/Online/TestAPIModJsonSerialization.cs

@@ -128,7 +128,7 @@ namespace osu.Game.Tests.Online
 
             public override IBeatmapConverter CreateBeatmapConverter(IBeatmap beatmap) => throw new NotImplementedException();
 
-            public override DifficultyCalculator CreateDifficultyCalculator(WorkingBeatmap beatmap) => throw new NotImplementedException();
+            public override DifficultyCalculator CreateDifficultyCalculator(IWorkingBeatmap beatmap) => throw new NotImplementedException();
 
             public override string Description { get; } = string.Empty;
             public override string ShortName { get; } = string.Empty;

osu.Game.Tests/Online/TestAPIModMessagePackSerialization.cs

@@ -90,7 +90,7 @@ namespace osu.Game.Tests.Online
 
             public override IBeatmapConverter CreateBeatmapConverter(IBeatmap beatmap) => throw new System.NotImplementedException();
 
-            public override DifficultyCalculator CreateDifficultyCalculator(WorkingBeatmap beatmap) => throw new System.NotImplementedException();
+            public override DifficultyCalculator CreateDifficultyCalculator(IWorkingBeatmap beatmap) => throw new System.NotImplementedException();
 
             public override string Description { get; } = string.Empty;
             public override string ShortName { get; } = string.Empty;

osu.Game.Tests/Testing/TestSceneRulesetDependencies.cs

@@ -79,7 +79,7 @@ namespace osu.Game.Tests.Testing
             public override IEnumerable<Mod> GetModsFor(ModType type) => Array.Empty<Mod>();
             public override DrawableRuleset CreateDrawableRulesetWith(IBeatmap beatmap, IReadOnlyList<Mod> mods = null) => null;
             public override IBeatmapConverter CreateBeatmapConverter(IBeatmap beatmap) => null;
-            public override DifficultyCalculator CreateDifficultyCalculator(WorkingBeatmap beatmap) => null;
+            public override DifficultyCalculator CreateDifficultyCalculator(IWorkingBeatmap beatmap) => null;
         }
 
         private class TestRulesetConfigManager : IRulesetConfigManager

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

@@ -293,7 +293,7 @@ namespace osu.Game.Tests.Visual.Gameplay
 
             public override IBeatmapConverter CreateBeatmapConverter(IBeatmap beatmap) => new TestBeatmapConverter(beatmap, null);
 
-            public override DifficultyCalculator CreateDifficultyCalculator(WorkingBeatmap beatmap) => throw new NotImplementedException();
+            public override DifficultyCalculator CreateDifficultyCalculator(IWorkingBeatmap beatmap) => throw new NotImplementedException();
 
             public override string Description { get; } = string.Empty;
 

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

@@ -49,7 +49,7 @@ namespace osu.Game.Tests.Visual.Gameplay
             public override IBeatmapConverter CreateBeatmapConverter(IBeatmap beatmap) =>
                 throw new System.NotImplementedException();
 
-            public override DifficultyCalculator CreateDifficultyCalculator(WorkingBeatmap beatmap) =>
+            public override DifficultyCalculator CreateDifficultyCalculator(IWorkingBeatmap beatmap) =>
                 throw new System.NotImplementedException();
 
             public override IEnumerable<KeyBinding> GetDefaultKeyBindings(int variant = 0)

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

@@ -182,7 +182,7 @@ namespace osu.Game.Tests.Visual.Gameplay
 
             public override IBeatmapConverter CreateBeatmapConverter(IBeatmap beatmap) => new TestBeatmapConverter(beatmap, this);
 
-            public override DifficultyCalculator CreateDifficultyCalculator(WorkingBeatmap beatmap) => throw new NotImplementedException();
+            public override DifficultyCalculator CreateDifficultyCalculator(IWorkingBeatmap beatmap) => throw new NotImplementedException();
 
             public override string Description { get; } = string.Empty;
 

osu.Game.Tests/Visual/SongSelect/TestSceneBeatmapRecommendations.cs

@@ -7,6 +7,7 @@ using System.Linq;
 using NUnit.Framework;
 using osu.Framework.Testing;
 using osu.Game.Beatmaps;
+using osu.Game.Extensions;
 using osu.Game.Online.API;
 using osu.Game.Online.API.Requests;
 using osu.Game.Online.API.Requests.Responses;
@@ -102,8 +103,8 @@ namespace osu.Game.Tests.Visual.SongSelect
         {
             BeatmapSetInfo catchSet = null, mixedSet = null;
 
-            AddStep("create catch beatmapset", () => catchSet = importBeatmapSet(0, new[] { new CatchRuleset().RulesetInfo }));
+            AddStep("create catch beatmapset", () => catchSet = importBeatmapSet(1, new[] { new CatchRuleset().RulesetInfo }));
-            AddStep("create mixed beatmapset", () => mixedSet = importBeatmapSet(1,
+            AddStep("create mixed beatmapset", () => mixedSet = importBeatmapSet(2,
                 new[] { new TaikoRuleset().RulesetInfo, new CatchRuleset().RulesetInfo, new ManiaRuleset().RulesetInfo }));
 
             AddAssert("all sets imported", () => ensureAllBeatmapSetsImported(new[] { catchSet, mixedSet }));
@@ -120,8 +121,8 @@ namespace osu.Game.Tests.Visual.SongSelect
         {
             BeatmapSetInfo osuSet = null, mixedSet = null;
 
-            AddStep("create osu! beatmapset", () => osuSet = importBeatmapSet(0, new[] { new OsuRuleset().RulesetInfo }));
+            AddStep("create osu! beatmapset", () => osuSet = importBeatmapSet(1, new[] { new OsuRuleset().RulesetInfo }));
-            AddStep("create mixed beatmapset", () => mixedSet = importBeatmapSet(1,
+            AddStep("create mixed beatmapset", () => mixedSet = importBeatmapSet(2,
                 new[] { new TaikoRuleset().RulesetInfo, new CatchRuleset().RulesetInfo, new ManiaRuleset().RulesetInfo }));
 
             AddAssert("all sets imported", () => ensureAllBeatmapSetsImported(new[] { osuSet, mixedSet }));
@@ -138,8 +139,8 @@ namespace osu.Game.Tests.Visual.SongSelect
         {
             BeatmapSetInfo osuSet = null, mixedSet = null;
 
-            AddStep("create osu! beatmapset", () => osuSet = importBeatmapSet(0, new[] { new OsuRuleset().RulesetInfo }));
+            AddStep("create osu! beatmapset", () => osuSet = importBeatmapSet(1, new[] { new OsuRuleset().RulesetInfo }));
-            AddStep("create mixed beatmapset", () => mixedSet = importBeatmapSet(1,
+            AddStep("create mixed beatmapset", () => mixedSet = importBeatmapSet(2,
                 new[] { new TaikoRuleset().RulesetInfo, new CatchRuleset().RulesetInfo, new TaikoRuleset().RulesetInfo }));
 
             AddAssert("all sets imported", () => ensureAllBeatmapSetsImported(new[] { osuSet, mixedSet }));
@@ -156,8 +157,8 @@ namespace osu.Game.Tests.Visual.SongSelect
         {
             BeatmapSetInfo osuSet = null, maniaSet = null;
 
-            AddStep("create osu! beatmapset", () => osuSet = importBeatmapSet(0, new[] { new OsuRuleset().RulesetInfo }));
+            AddStep("create osu! beatmapset", () => osuSet = importBeatmapSet(1, new[] { new OsuRuleset().RulesetInfo }));
-            AddStep("create mania beatmapset", () => maniaSet = importBeatmapSet(1, Enumerable.Repeat(new ManiaRuleset().RulesetInfo, 10)));
+            AddStep("create mania beatmapset", () => maniaSet = importBeatmapSet(2, Enumerable.Repeat(new ManiaRuleset().RulesetInfo, 10)));
 
             AddAssert("all sets imported", () => ensureAllBeatmapSetsImported(new[] { osuSet, maniaSet }));
 
@@ -203,11 +204,7 @@ namespace osu.Game.Tests.Visual.SongSelect
             AddStep("present beatmap", () => Game.PresentBeatmap(getImport()));
 
             AddUntilStep("wait for song select", () => Game.ScreenStack.CurrentScreen is Screens.Select.SongSelect);
-            AddUntilStep("recommended beatmap displayed", () =>
+            AddUntilStep("recommended beatmap displayed", () => Game.Beatmap.Value.BeatmapInfo.MatchesOnlineID(getImport().Beatmaps[expectedDiff - 1]));
-            {
-                int? expectedID = getImport().Beatmaps[expectedDiff - 1].OnlineID;
-                return Game.Beatmap.Value.BeatmapInfo.OnlineID == expectedID;
-            });
         }
     }
 }

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

@@ -199,7 +199,7 @@ namespace osu.Game.Tests.Visual.UserInterface
 
                 public override IBeatmapConverter CreateBeatmapConverter(IBeatmap beatmap) => throw new NotImplementedException();
 
-                public override DifficultyCalculator CreateDifficultyCalculator(WorkingBeatmap beatmap) => throw new NotImplementedException();
+                public override DifficultyCalculator CreateDifficultyCalculator(IWorkingBeatmap beatmap) => throw new NotImplementedException();
 
                 public override string Description { get; } = "test";
                 public override string ShortName { get; } = "tst";

osu.Game/Beatmaps/BeatmapInfo.cs

@@ -154,14 +154,17 @@ namespace osu.Game.Beatmaps
 
         public bool Equals(BeatmapInfo other)
         {
-            if (ID == 0 || other?.ID == 0)
+            if (ReferenceEquals(this, other)) return true;
-                // one of the two BeatmapInfos we are comparing isn't sourced from a database.
+            if (other == null) return false;
-                // fall back to reference equality.
-                return ReferenceEquals(this, other);
 
-            return ID == other?.ID;
+            if (ID != 0 && other.ID != 0)
+                return ID == other.ID;
+
+            return false;
         }
 
+        public bool Equals(IBeatmapInfo other) => other is BeatmapInfo b && Equals(b);
+
         public bool AudioEquals(BeatmapInfo other) => other != null && BeatmapSet != null && other.BeatmapSet != null &&
                                                       BeatmapSet.Hash == other.BeatmapSet.Hash &&
                                                       (Metadata ?? BeatmapSet.Metadata).AudioFile == (other.Metadata ?? other.BeatmapSet.Metadata).AudioFile;

osu.Game/Beatmaps/BeatmapSetInfo.cs

@@ -69,21 +69,17 @@ namespace osu.Game.Beatmaps
 
         public bool Equals(BeatmapSetInfo other)
         {
-            if (other == null)
+            if (ReferenceEquals(this, other)) return true;
-                return false;
+            if (other == null) return false;
 
             if (ID != 0 && other.ID != 0)
                 return ID == other.ID;
 
-            if (OnlineID.HasValue && other.OnlineID.HasValue)
+            return false;
-                return OnlineID == other.OnlineID;
-
-            if (!string.IsNullOrEmpty(Hash) && !string.IsNullOrEmpty(other.Hash))
-                return Hash == other.Hash;
-
-            return ReferenceEquals(this, other);
         }
 
+        public bool Equals(IBeatmapSetInfo other) => other is BeatmapSetInfo b && Equals(b);
+
         #region Implementation of IHasOnlineID
 
         int IHasOnlineID<int>.OnlineID => OnlineID ?? -1;

osu.Game/Beatmaps/DummyWorkingBeatmap.cs

@@ -69,7 +69,7 @@ namespace osu.Game.Beatmaps
 
                 public override IBeatmapConverter CreateBeatmapConverter(IBeatmap beatmap) => new DummyBeatmapConverter { Beatmap = beatmap };
 
-                public override DifficultyCalculator CreateDifficultyCalculator(WorkingBeatmap beatmap) => null;
+                public override DifficultyCalculator CreateDifficultyCalculator(IWorkingBeatmap beatmap) => null;
 
                 public override string Description => "dummy";
 

osu.Game/Beatmaps/IBeatmapInfo.cs

@@ -1,6 +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.
 
+using System;
 using osu.Game.Database;
 using osu.Game.Rulesets;
 
@@ -11,7 +12,7 @@ namespace osu.Game.Beatmaps
     /// <summary>
     /// A single beatmap difficulty.
     /// </summary>
-    public interface IBeatmapInfo : IHasOnlineID<int>
+    public interface IBeatmapInfo : IHasOnlineID<int>, IEquatable<IBeatmapInfo>
     {
         /// <summary>
         /// The user-specified name given to this beatmap.

osu.Game/Beatmaps/IBeatmapSetInfo.cs

@@ -12,7 +12,7 @@ namespace osu.Game.Beatmaps
     /// <summary>
     /// A representation of a collection of beatmap difficulties, generally packaged as an ".osz" archive.
     /// </summary>
-    public interface IBeatmapSetInfo : IHasOnlineID<int>
+    public interface IBeatmapSetInfo : IHasOnlineID<int>, IEquatable<IBeatmapSetInfo>
     {
         /// <summary>
         /// The date when this beatmap was imported.

osu.Game/Beatmaps/IWorkingBeatmap.cs

@@ -95,7 +95,7 @@ namespace osu.Game.Beatmaps
         /// <param name="cancellationToken">Cancellation token that cancels the beatmap loading process. If not provided, a default timeout of 10,000ms will be applied to the load process.</param>
         /// <returns>The converted <see cref="IBeatmap"/>.</returns>
         /// <exception cref="BeatmapInvalidForRulesetException">If <see cref="Beatmap"/> could not be converted to <paramref name="ruleset"/>.</exception>
-        IBeatmap GetPlayableBeatmap(RulesetInfo ruleset, IReadOnlyList<Mod> mods = null, CancellationToken? cancellationToken = null);
+        IBeatmap GetPlayableBeatmap(IRulesetInfo ruleset, IReadOnlyList<Mod> mods = null, CancellationToken? cancellationToken = null);
 
         /// <summary>
         /// Load a new audio track instance for this beatmap. This should be called once before accessing <see cref="Track"/>.

osu.Game/Beatmaps/WorkingBeatmap.cs

@@ -78,7 +78,7 @@ namespace osu.Game.Beatmaps
         /// <returns>The applicable <see cref="IBeatmapConverter"/>.</returns>
         protected virtual IBeatmapConverter CreateBeatmapConverter(IBeatmap beatmap, Ruleset ruleset) => ruleset.CreateBeatmapConverter(beatmap);
 
-        public virtual IBeatmap GetPlayableBeatmap(RulesetInfo ruleset, IReadOnlyList<Mod> mods = null, CancellationToken? cancellationToken = null)
+        public virtual IBeatmap GetPlayableBeatmap(IRulesetInfo ruleset, IReadOnlyList<Mod> mods = null, CancellationToken? cancellationToken = null)
         {
             var token = cancellationToken ?? new CancellationTokenSource(10000).Token;
             mods ??= Array.Empty<Mod>();

osu.Game/Collections/BeatmapCollection.cs

@@ -25,7 +25,7 @@ namespace osu.Game.Collections
         /// <summary>
         /// The beatmaps contained by the collection.
         /// </summary>
-        public readonly BindableList<BeatmapInfo> Beatmaps = new BindableList<BeatmapInfo>();
+        public readonly BindableList<IBeatmapInfo> Beatmaps = new BindableList<IBeatmapInfo>();
 
         /// <summary>
         /// The date when this collection was last modified.

osu.Game/Collections/CollectionFilterDropdown.cs

@@ -39,7 +39,7 @@ namespace osu.Game.Collections
         }
 
         private readonly IBindableList<BeatmapCollection> collections = new BindableList<BeatmapCollection>();
-        private readonly IBindableList<BeatmapInfo> beatmaps = new BindableList<BeatmapInfo>();
+        private readonly IBindableList<IBeatmapInfo> beatmaps = new BindableList<IBeatmapInfo>();
         private readonly BindableList<CollectionFilterMenuItem> filters = new BindableList<CollectionFilterMenuItem>();
 
         [Resolved(CanBeNull = true)]
@@ -200,7 +200,7 @@ namespace osu.Game.Collections
             private IBindable<WorkingBeatmap> beatmap { get; set; }
 
             [CanBeNull]
-            private readonly BindableList<BeatmapInfo> collectionBeatmaps;
+            private readonly BindableList<IBeatmapInfo> collectionBeatmaps;
 
             [NotNull]
             private readonly Bindable<string> collectionName;

osu.Game/Database/IHasOnlineID.cs

@@ -1,11 +1,14 @@
 // 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;
+
 #nullable enable
 
 namespace osu.Game.Database
 {
     public interface IHasOnlineID<out T>
+        where T : IEquatable<T>
     {
         /// <summary>
         /// The server-side ID representing this instance, if one exists. Any value 0 or less denotes a missing ID (except in special cases where autoincrement is not used, like rulesets).

osu.Game/Extensions/ModelExtensions.cs

@@ -2,10 +2,14 @@
 // See the LICENCE file in the repository root for full licence text.
 
 using osu.Game.Beatmaps;
+using osu.Game.Database;
+using osu.Game.Online.API.Requests.Responses;
 using osu.Game.Rulesets;
 using osu.Game.Scoring;
 using osu.Game.Users;
 
+#nullable enable
+
 namespace osu.Game.Extensions
 {
     public static class ModelExtensions
@@ -22,9 +26,9 @@ namespace osu.Game.Extensions
         /// extension method type inference rules cause this method to call itself and cause a stack overflow.
         /// </para>
         /// </remarks>
-        public static string GetDisplayString(this object model)
+        public static string GetDisplayString(this object? model)
         {
-            string result = null;
+            string? result = null;
 
             switch (model)
             {
@@ -57,5 +61,59 @@ namespace osu.Game.Extensions
             result ??= model?.ToString() ?? @"null";
             return result;
         }
+
+        /// <summary>
+        /// Check whether the online ID of two <see cref="IBeatmapSetInfo"/>s match.
+        /// </summary>
+        /// <param name="instance">The instance to compare.</param>
+        /// <param name="other">The other instance to compare against.</param>
+        /// <returns>Whether online IDs match. If either instance is missing an online ID, this will return false.</returns>
+        public static bool MatchesOnlineID(this IBeatmapSetInfo? instance, IBeatmapSetInfo? other) => matchesOnlineID(instance, other);
+
+        /// <summary>
+        /// Check whether the online ID of two <see cref="IBeatmapInfo"/>s match.
+        /// </summary>
+        /// <param name="instance">The instance to compare.</param>
+        /// <param name="other">The other instance to compare against.</param>
+        /// <returns>Whether online IDs match. If either instance is missing an online ID, this will return false.</returns>
+        public static bool MatchesOnlineID(this IBeatmapInfo? instance, IBeatmapInfo? other) => matchesOnlineID(instance, other);
+
+        /// <summary>
+        /// Check whether the online ID of two <see cref="IRulesetInfo"/>s match.
+        /// </summary>
+        /// <param name="instance">The instance to compare.</param>
+        /// <param name="other">The other instance to compare against.</param>
+        /// <returns>Whether online IDs match. If either instance is missing an online ID, this will return false.</returns>
+        public static bool MatchesOnlineID(this IRulesetInfo? instance, IRulesetInfo? other) => matchesOnlineID(instance, other);
+
+        /// <summary>
+        /// Check whether the online ID of two <see cref="APIUser"/>s match.
+        /// </summary>
+        /// <param name="instance">The instance to compare.</param>
+        /// <param name="other">The other instance to compare against.</param>
+        /// <returns>Whether online IDs match. If either instance is missing an online ID, this will return false.</returns>
+        public static bool MatchesOnlineID(this APIUser? instance, APIUser? other) => matchesOnlineID(instance, other);
+
+        private static bool matchesOnlineID(this IHasOnlineID<long>? instance, IHasOnlineID<long>? other)
+        {
+            if (instance == null || other == null)
+                return false;
+
+            if (instance.OnlineID < 0 || other.OnlineID < 0)
+                return false;
+
+            return instance.OnlineID.Equals(other.OnlineID);
+        }
+
+        private static bool matchesOnlineID(this IHasOnlineID<int>? instance, IHasOnlineID<int>? other)
+        {
+            if (instance == null || other == null)
+                return false;
+
+            if (instance.OnlineID < 0 || other.OnlineID < 0)
+                return false;
+
+            return instance.OnlineID.Equals(other.OnlineID);
+        }
     }
 }

osu.Game/Models/RealmBeatmap.cs

@@ -20,7 +20,7 @@ namespace osu.Game.Models
     [ExcludeFromDynamicCompile]
     [Serializable]
     [MapTo("Beatmap")]
-    public class RealmBeatmap : RealmObject, IHasGuidPrimaryKey, IBeatmapInfo
+    public class RealmBeatmap : RealmObject, IHasGuidPrimaryKey, IBeatmapInfo, IEquatable<RealmBeatmap>
     {
         [PrimaryKey]
         public Guid ID { get; set; } = Guid.NewGuid();
@@ -98,6 +98,16 @@ namespace osu.Game.Models
 
         #endregion
 
+        public bool Equals(RealmBeatmap? other)
+        {
+            if (ReferenceEquals(this, other)) return true;
+            if (other == null) return false;
+
+            return ID == other.ID;
+        }
+
+        public bool Equals(IBeatmapInfo? other) => other is RealmBeatmap b && Equals(b);
+
         public bool AudioEquals(RealmBeatmap? other) => other != null
                                                         && BeatmapSet != null
                                                         && other.BeatmapSet != null

osu.Game/Models/RealmBeatmapSet.cs

@@ -7,6 +7,7 @@ using System.Linq;
 using osu.Framework.Testing;
 using osu.Game.Beatmaps;
 using osu.Game.Database;
+using osu.Game.Extensions;
 using Realms;
 
 #nullable enable
@@ -53,25 +54,18 @@ namespace osu.Game.Models
         /// <param name="filename">The name of the file to get the storage path of.</param>
         public string? GetPathForFile(string filename) => Files.SingleOrDefault(f => string.Equals(f.Filename, filename, StringComparison.OrdinalIgnoreCase))?.File.StoragePath;
 
-        public override string ToString() => Metadata?.ToString() ?? base.ToString();
-
         public bool Equals(RealmBeatmapSet? other)
         {
-            if (other == null)
+            if (ReferenceEquals(this, other)) return true;
-                return false;
+            if (other == null) return false;
 
-            if (IsManaged && other.IsManaged)
             return ID == other.ID;
-
-            if (OnlineID > 0 && other.OnlineID > 0)
-                return OnlineID == other.OnlineID;
-
-            if (!string.IsNullOrEmpty(Hash) && !string.IsNullOrEmpty(other.Hash))
-                return Hash == other.Hash;
-
-            return ReferenceEquals(this, other);
         }
 
+        public override string ToString() => Metadata?.GetDisplayString() ?? base.ToString();
+
+        public bool Equals(IBeatmapSetInfo? other) => other is RealmBeatmapSet b && Equals(b);
+
         IEnumerable<IBeatmapInfo> IBeatmapSetInfo.Beatmaps => Beatmaps;
 
         IEnumerable<INamedFileUsage> IBeatmapSetInfo.Files => Files;

osu.Game/Online/API/Requests/Responses/APIBeatmap.cs

@@ -4,6 +4,7 @@
 using System;
 using Newtonsoft.Json;
 using osu.Game.Beatmaps;
+using osu.Game.Extensions;
 using osu.Game.Rulesets;
 
 #nullable enable
@@ -103,5 +104,7 @@ namespace osu.Game.Online.API.Requests.Responses
         public string Hash => throw new NotImplementedException();
 
         #endregion
+
+        public bool Equals(IBeatmapInfo? other) => other is APIBeatmap b && this.MatchesOnlineID(b);
     }
 }

osu.Game/Online/API/Requests/Responses/APIBeatmapSet.cs

@@ -6,6 +6,7 @@ using System.Collections.Generic;
 using Newtonsoft.Json;
 using osu.Game.Beatmaps;
 using osu.Game.Database;
+using osu.Game.Extensions;
 
 #nullable enable
 
@@ -141,5 +142,7 @@ namespace osu.Game.Online.API.Requests.Responses
         double IBeatmapSetInfo.MaxBPM => BPM;
 
         #endregion
+
+        public bool Equals(IBeatmapSetInfo? other) => other is APIBeatmapSet b && this.MatchesOnlineID(b);
     }
 }

osu.Game/Online/API/Requests/Responses/APIUser.cs

@@ -7,6 +7,7 @@ using System.Linq;
 using JetBrains.Annotations;
 using Newtonsoft.Json;
 using osu.Framework.Bindables;
+using osu.Game.Extensions;
 using osu.Game.Users;
 
 namespace osu.Game.Online.API.Requests.Responses
@@ -240,6 +241,6 @@ namespace osu.Game.Online.API.Requests.Responses
 
         public int OnlineID => Id;
 
-        public bool Equals(APIUser other) => OnlineID == other?.OnlineID;
+        public bool Equals(APIUser other) => this.MatchesOnlineID(other);
     }
 }

osu.Game/Online/Chat/StandAloneChatDisplay.cs

@@ -41,8 +41,10 @@ namespace osu.Game.Online.Chat
         /// <param name="postingTextbox">Whether a textbox for posting new messages should be displayed.</param>
         public StandAloneChatDisplay(bool postingTextbox = false)
         {
+            const float corner_radius = 10;
+
             this.postingTextbox = postingTextbox;
-            CornerRadius = 10;
+            CornerRadius = corner_radius;
             Masking = true;
 
             InternalChildren = new Drawable[]
@@ -62,6 +64,7 @@ namespace osu.Game.Online.Chat
                     RelativeSizeAxes = Axes.X,
                     Height = textbox_height,
                     PlaceholderText = "type your message",
+                    CornerRadius = corner_radius,
                     ReleaseFocusOnCommit = false,
                     HoldFocus = true,
                     Anchor = Anchor.BottomLeft,

osu.Game/Online/Rooms/MultiplayerScore.cs

@@ -10,6 +10,7 @@ using Newtonsoft.Json.Converters;
 using osu.Game.Beatmaps;
 using osu.Game.Online.API;
 using osu.Game.Online.API.Requests.Responses;
+using osu.Game.Rulesets;
 using osu.Game.Rulesets.Mods;
 using osu.Game.Rulesets.Scoring;
 using osu.Game.Scoring;
@@ -62,7 +63,7 @@ namespace osu.Game.Online.Rooms
         [CanBeNull]
         public MultiplayerScoresAround ScoresAround { get; set; }
 
-        public ScoreInfo CreateScoreInfo(PlaylistItem playlistItem, [NotNull] BeatmapInfo beatmap)
+        public ScoreInfo CreateScoreInfo(RulesetStore rulesets, PlaylistItem playlistItem, [NotNull] BeatmapInfo beatmap)
         {
             var rulesetInstance = playlistItem.Ruleset.Value.CreateInstance();
 
@@ -73,7 +74,7 @@ namespace osu.Game.Online.Rooms
                 MaxCombo = MaxCombo,
                 BeatmapInfo = beatmap,
                 BeatmapInfoID = playlistItem.BeatmapID,
-                Ruleset = playlistItem.Ruleset.Value,
+                Ruleset = rulesets.GetRuleset(playlistItem.RulesetID),
                 RulesetID = playlistItem.RulesetID,
                 Statistics = Statistics,
                 User = User,

osu.Game/Online/Rooms/PlaylistItem.cs

@@ -34,7 +34,7 @@ namespace osu.Game.Online.Rooms
         public readonly Bindable<IBeatmapInfo> Beatmap = new Bindable<IBeatmapInfo>();
 
         [JsonIgnore]
-        public readonly Bindable<RulesetInfo> Ruleset = new Bindable<RulesetInfo>();
+        public readonly Bindable<IRulesetInfo> Ruleset = new Bindable<IRulesetInfo>();
 
         [JsonIgnore]
         public readonly BindableList<Mod> AllowedMods = new BindableList<Mod>();
@@ -66,7 +66,7 @@ namespace osu.Game.Online.Rooms
         public PlaylistItem()
         {
             Beatmap.BindValueChanged(beatmap => BeatmapID = beatmap.NewValue?.OnlineID ?? -1);
-            Ruleset.BindValueChanged(ruleset => RulesetID = ruleset.NewValue?.ID ?? 0);
+            Ruleset.BindValueChanged(ruleset => RulesetID = ruleset.NewValue?.OnlineID ?? 0);
         }
 
         public void MapObjects(RulesetStore rulesets)

osu.Game/Overlays/BeatmapListing/Panels/BeatmapPanelDownloadButton.cs

@@ -8,6 +8,7 @@ using osu.Framework.Graphics;
 using osu.Framework.Graphics.Containers;
 using osu.Game.Beatmaps;
 using osu.Game.Configuration;
+using osu.Game.Extensions;
 using osu.Game.Graphics.Containers;
 using osu.Game.Graphics.UserInterface;
 using osu.Game.Online;
@@ -80,7 +81,7 @@ namespace osu.Game.Overlays.BeatmapListing.Panels
                     case DownloadState.LocallyAvailable:
                         Predicate<BeatmapInfo> findPredicate = null;
                         if (SelectedBeatmap.Value != null)
-                            findPredicate = b => b.OnlineID == SelectedBeatmap.Value.OnlineID;
+                            findPredicate = b => b.MatchesOnlineID(SelectedBeatmap.Value);
 
                         game?.PresentBeatmap(beatmapSet, findPredicate);
                         break;

osu.Game/Overlays/BeatmapSet/BeatmapPicker.cs

@@ -14,6 +14,7 @@ using osu.Framework.Graphics.Sprites;
 using osu.Framework.Input.Events;
 using osu.Game.Beatmaps;
 using osu.Game.Beatmaps.Drawables;
+using osu.Game.Extensions;
 using osu.Game.Graphics;
 using osu.Game.Graphics.Containers;
 using osu.Game.Graphics.Sprites;
@@ -166,7 +167,7 @@ namespace osu.Game.Overlays.BeatmapSet
             if (BeatmapSet != null)
             {
                 Difficulties.ChildrenEnumerable = BeatmapSet.Beatmaps
-                                                            .Where(b => b.Ruleset.OnlineID == ruleset.Value?.OnlineID)
+                                                            .Where(b => b.Ruleset.MatchesOnlineID(ruleset.Value))
                                                             .OrderBy(b => b.StarRating)
                                                             .Select(b => new DifficultySelectorButton(b)
                                                             {

osu.Game/Overlays/BeatmapSet/BeatmapRulesetTabItem.cs

@@ -7,6 +7,7 @@ using osu.Framework.Bindables;
 using osu.Framework.Graphics;
 using osu.Framework.Graphics.Containers;
 using osu.Framework.Graphics.Shapes;
+using osu.Game.Extensions;
 using osu.Game.Graphics;
 using osu.Game.Graphics.Sprites;
 using osu.Game.Online.API.Requests.Responses;
@@ -64,7 +65,7 @@ namespace osu.Game.Overlays.BeatmapSet
 
             BeatmapSet.BindValueChanged(setInfo =>
             {
-                int beatmapsCount = setInfo.NewValue?.Beatmaps.Count(b => b.Ruleset.OnlineID == Value.OnlineID) ?? 0;
+                int beatmapsCount = setInfo.NewValue?.Beatmaps.Count(b => b.Ruleset.MatchesOnlineID(Value)) ?? 0;
 
                 count.Text = beatmapsCount.ToString();
                 countContainer.FadeTo(beatmapsCount > 0 ? 1 : 0);

osu.Game/Overlays/Music/Playlist.cs

@@ -29,7 +29,7 @@ namespace osu.Game.Overlays.Music
             var items = (SearchContainer<RearrangeableListItem<BeatmapSetInfo>>)ListContainer;
 
             foreach (var item in items.OfType<PlaylistItem>())
-                item.InSelectedCollection = criteria.Collection?.Beatmaps.Any(b => b.BeatmapSet.Equals(item.Model)) ?? true;
+                item.InSelectedCollection = criteria.Collection?.Beatmaps.Any(b => item.Model.Equals(b.BeatmapSet)) ?? true;
 
             items.SearchTerm = criteria.SearchText;
         }

osu.Game/Rulesets/Difficulty/DifficultyCalculator.cs

@@ -28,10 +28,10 @@ namespace osu.Game.Rulesets.Difficulty
         private Mod[] playableMods;
         private double clockRate;
 
-        private readonly Ruleset ruleset;
+        private readonly IRulesetInfo ruleset;
-        private readonly WorkingBeatmap beatmap;
+        private readonly IWorkingBeatmap beatmap;
 
-        protected DifficultyCalculator(Ruleset ruleset, WorkingBeatmap beatmap)
+        protected DifficultyCalculator(IRulesetInfo ruleset, IWorkingBeatmap beatmap)
         {
             this.ruleset = ruleset;
             this.beatmap = beatmap;
@@ -145,7 +145,7 @@ namespace osu.Game.Rulesets.Difficulty
         {
             playableMods = mods.Select(m => m.DeepClone()).ToArray();
 
-            Beatmap = beatmap.GetPlayableBeatmap(ruleset.RulesetInfo, playableMods, cancellationToken: cancellationToken);
+            Beatmap = beatmap.GetPlayableBeatmap(ruleset, playableMods, cancellationToken);
 
             var track = new TrackVirtual(10000);
             playableMods.OfType<IApplicableToTrack>().ForEach(m => m.ApplyToTrack(track));

osu.Game/Rulesets/Ruleset.cs

@@ -222,7 +222,7 @@ namespace osu.Game.Rulesets
         /// <returns>The <see cref="IBeatmapProcessor"/>.</returns>
         public virtual IBeatmapProcessor CreateBeatmapProcessor(IBeatmap beatmap) => null;
 
-        public abstract DifficultyCalculator CreateDifficultyCalculator(WorkingBeatmap beatmap);
+        public abstract DifficultyCalculator CreateDifficultyCalculator(IWorkingBeatmap beatmap);
 
         /// <summary>
         /// Optionally creates a <see cref="PerformanceCalculator"/> to generate performance data from the provided score.
@@ -240,7 +240,7 @@ namespace osu.Game.Rulesets
         /// <param name="score">The score to be processed.</param>
         /// <returns>A performance calculator instance for the provided score.</returns>
         [CanBeNull]
-        public PerformanceCalculator CreatePerformanceCalculator(WorkingBeatmap beatmap, ScoreInfo score)
+        public PerformanceCalculator CreatePerformanceCalculator(IWorkingBeatmap beatmap, ScoreInfo score)
         {
             var difficultyCalculator = CreateDifficultyCalculator(beatmap);
             var difficultyAttributes = difficultyCalculator.Calculate(score.Mods);

osu.Game/Screens/OnlinePlay/DrawableRoomPlaylistItem.cs

@@ -46,7 +46,7 @@ namespace osu.Game.Screens.OnlinePlay
         private ModDisplay modDisplay;
 
         private readonly Bindable<IBeatmapInfo> beatmap = new Bindable<IBeatmapInfo>();
-        private readonly Bindable<RulesetInfo> ruleset = new Bindable<RulesetInfo>();
+        private readonly Bindable<IRulesetInfo> ruleset = new Bindable<IRulesetInfo>();
         private readonly BindableList<Mod> requiredMods = new BindableList<Mod>();
 
         public readonly PlaylistItem Item;

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

@@ -82,7 +82,7 @@ namespace osu.Game.Screens.OnlinePlay.Lounge.Components
                 {
                     bool matchingFilter = true;
 
-                    matchingFilter &= r.Room.Playlist.Count == 0 || criteria.Ruleset == null || r.Room.Playlist.Any(i => i.Ruleset.Value.Equals(criteria.Ruleset));
+                    matchingFilter &= r.Room.Playlist.Count == 0 || criteria.Ruleset == null || r.Room.Playlist.Any(i => i.Ruleset.Value.MatchesOnlineID(criteria.Ruleset));
 
                     if (!string.IsNullOrEmpty(criteria.SearchString))
                         matchingFilter &= r.FilterTerms.Any(term => term.Contains(criteria.SearchString, StringComparison.InvariantCultureIgnoreCase));

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

@@ -18,6 +18,7 @@ using osu.Game.Beatmaps;
 using osu.Game.Online.Rooms;
 using osu.Game.Overlays;
 using osu.Game.Overlays.Mods;
+using osu.Game.Rulesets;
 using osu.Game.Rulesets.Mods;
 using osu.Game.Screens.OnlinePlay.Match.Components;
 
@@ -59,6 +60,9 @@ namespace osu.Game.Screens.OnlinePlay.Match
         [Resolved]
         private BeatmapManager beatmapManager { get; set; }
 
+        [Resolved]
+        private RulesetStore rulesets { get; set; }
+
         [Resolved(canBeNull: true)]
         protected OnlinePlayScreen ParentScreen { get; private set; }
 
@@ -344,7 +348,7 @@ namespace osu.Game.Screens.OnlinePlay.Match
 
             UpdateMods();
 
-            Ruleset.Value = selected.Ruleset.Value;
+            Ruleset.Value = rulesets.GetRuleset(selected.RulesetID);
 
             if (!selected.AllowedMods.Any())
             {

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

@@ -8,6 +8,7 @@ using System.Threading.Tasks;
 using osu.Framework.Allocation;
 using osu.Framework.Bindables;
 using osu.Framework.Screens;
+using osu.Game.Extensions;
 using osu.Game.Online.Rooms;
 using osu.Game.Rulesets;
 using osu.Game.Scoring;
@@ -32,10 +33,10 @@ namespace osu.Game.Screens.OnlinePlay.Playlists
         private void load(IBindable<RulesetInfo> ruleset)
         {
             // Sanity checks to ensure that PlaylistsPlayer matches the settings for the current PlaylistItem
-            if (Beatmap.Value.BeatmapInfo.OnlineID != PlaylistItem.Beatmap.Value.OnlineID)
+            if (!Beatmap.Value.BeatmapInfo.MatchesOnlineID(PlaylistItem.Beatmap.Value))
                 throw new InvalidOperationException("Current Beatmap does not match PlaylistItem's Beatmap");
 
-            if (ruleset.Value.ID != PlaylistItem.Ruleset.Value.ID)
+            if (!ruleset.Value.MatchesOnlineID(PlaylistItem.Ruleset.Value))
                 throw new InvalidOperationException("Current Ruleset does not match PlaylistItem's Ruleset");
 
             if (!PlaylistItem.RequiredMods.All(m => Mods.Value.Any(m.Equals)))

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

@@ -12,6 +12,7 @@ using osu.Framework.Graphics.Containers;
 using osu.Game.Graphics.UserInterface;
 using osu.Game.Online.API;
 using osu.Game.Online.Rooms;
+using osu.Game.Rulesets;
 using osu.Game.Scoring;
 using osu.Game.Screens.Ranking;
 
@@ -35,6 +36,9 @@ namespace osu.Game.Screens.OnlinePlay.Playlists
         [Resolved]
         private ScoreManager scoreManager { get; set; }
 
+        [Resolved]
+        private RulesetStore rulesets { get; set; }
+
         public PlaylistsResultsScreen(ScoreInfo score, long roomId, PlaylistItem playlistItem, bool allowRetry, bool allowWatchingReplay = true)
             : base(score, allowRetry, allowWatchingReplay)
         {
@@ -169,7 +173,7 @@ namespace osu.Game.Screens.OnlinePlay.Playlists
         /// <param name="pivot">An optional pivot around which the scores were retrieved.</param>
         private void performSuccessCallback([NotNull] Action<IEnumerable<ScoreInfo>> callback, [NotNull] List<MultiplayerScore> scores, [CanBeNull] MultiplayerScores pivot = null)
         {
-            var scoreInfos = scores.Select(s => s.CreateScoreInfo(playlistItem, Beatmap.Value.BeatmapInfo)).ToArray();
+            var scoreInfos = scores.Select(s => s.CreateScoreInfo(rulesets, playlistItem, Beatmap.Value.BeatmapInfo)).ToArray();
 
             // Score panels calculate total score before displaying, which can take some time. In order to count that calculation as part of the loading spinner display duration,
             // calculate the total scores locally before invoking the success callback.

osu.Game/Screens/Play/HUD/PerformancePointsCounter.cs

@@ -216,7 +216,7 @@ namespace osu.Game.Screens.Play.HUD
                 this.gameplayBeatmap = gameplayBeatmap;
             }
 
-            public override IBeatmap GetPlayableBeatmap(RulesetInfo ruleset, IReadOnlyList<Mod> mods = null, CancellationToken? cancellationToken = null)
+            public override IBeatmap GetPlayableBeatmap(IRulesetInfo ruleset, IReadOnlyList<Mod> mods = null, CancellationToken? cancellationToken = null)
                 => gameplayBeatmap;
 
             protected override IBeatmap GetBeatmap() => gameplayBeatmap;

osu.Game/Screens/Select/Leaderboards/BeatmapLeaderboard.cs

@@ -116,6 +116,8 @@ namespace osu.Game.Screens.Select.Leaderboards
             loadCancellationSource?.Cancel();
             loadCancellationSource = new CancellationTokenSource();
 
+            var cancellationToken = loadCancellationSource.Token;
+
             if (BeatmapInfo == null)
             {
                 PlaceholderState = PlaceholderState.NoneSelected;
@@ -140,7 +142,7 @@ namespace osu.Game.Screens.Select.Leaderboards
                     scores = scores.Where(s => s.Mods.Any(m => selectedMods.Contains(m.Acronym)));
                 }
 
-                scoreManager.OrderByTotalScoreAsync(scores.ToArray(), loadCancellationSource.Token)
+                scoreManager.OrderByTotalScoreAsync(scores.ToArray(), cancellationToken)
                             .ContinueWith(ordered => scoresCallback?.Invoke(ordered.Result), TaskContinuationOptions.OnlyOnRanToCompletion);
 
                 return null;
@@ -176,10 +178,10 @@ namespace osu.Game.Screens.Select.Leaderboards
 
             req.Success += r =>
             {
-                scoreManager.OrderByTotalScoreAsync(r.Scores.Select(s => s.CreateScoreInfo(rulesets, BeatmapInfo)).ToArray(), loadCancellationSource.Token)
+                scoreManager.OrderByTotalScoreAsync(r.Scores.Select(s => s.CreateScoreInfo(rulesets, BeatmapInfo)).ToArray(), cancellationToken)
                             .ContinueWith(ordered => Schedule(() =>
                             {
-                                if (loadCancellationSource.IsCancellationRequested)
+                                if (cancellationToken.IsCancellationRequested)
                                     return;
 
                                 scoresCallback?.Invoke(ordered.Result);

osu.Game/Tests/Beatmaps/DifficultyCalculatorTest.cs

@@ -28,7 +28,7 @@ namespace osu.Game.Tests.Beatmaps
             Assert.That(CreateDifficultyCalculator(getBeatmap(name)).Calculate(mods).StarRating, Is.EqualTo(expected).Within(0.00001));
         }
 
-        private WorkingBeatmap getBeatmap(string name)
+        private IWorkingBeatmap getBeatmap(string name)
         {
             using (var resStream = openResource($"{resource_namespace}.{name}.osu"))
             using (var stream = new LineBufferedReader(resStream))
@@ -53,7 +53,7 @@ namespace osu.Game.Tests.Beatmaps
             return Assembly.LoadFrom(Path.Combine(localPath, $"{ResourceAssembly}.dll")).GetManifestResourceStream($@"{ResourceAssembly}.Resources.{name}");
         }
 
-        protected abstract DifficultyCalculator CreateDifficultyCalculator(WorkingBeatmap beatmap);
+        protected abstract DifficultyCalculator CreateDifficultyCalculator(IWorkingBeatmap beatmap);
 
         protected abstract Ruleset CreateRuleset();
     }

osu.Game/Updater/GitHubAsset.cs

@@ -0,0 +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.
+
+using Newtonsoft.Json;
+
+namespace osu.Game.Updater
+{
+    public class GitHubAsset
+    {
+        [JsonProperty("name")]
+        public string Name { get; set; }
+
+        [JsonProperty("browser_download_url")]
+        public string BrowserDownloadUrl { get; set; }
+    }
+}

osu.Game/Updater/GitHubRelease.cs

@@ -0,0 +1,20 @@
+// 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 Newtonsoft.Json;
+
+namespace osu.Game.Updater
+{
+    public class GitHubRelease
+    {
+        [JsonProperty("html_url")]
+        public string HtmlUrl { get; set; }
+
+        [JsonProperty("tag_name")]
+        public string TagName { get; set; }
+
+        [JsonProperty("assets")]
+        public List<GitHubAsset> Assets { get; set; }
+    }
+}

osu.Game/Updater/NoActionUpdateManager.cs

@@ -0,0 +1,67 @@
+// 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 System.Threading.Tasks;
+using osu.Framework.Allocation;
+using osu.Framework.Graphics.Sprites;
+using osu.Framework.Platform;
+using osu.Game.Online.API;
+using osu.Game.Overlays.Notifications;
+
+namespace osu.Game.Updater
+{
+    /// <summary>
+    /// An update manager that shows notifications if a newer release is detected.
+    /// This is a case where updates are handled externally by a package manager or other means, so no action is performed on clicking the notification.
+    /// </summary>
+    public class NoActionUpdateManager : UpdateManager
+    {
+        private string version;
+
+        [Resolved]
+        private GameHost host { get; set; }
+
+        [BackgroundDependencyLoader]
+        private void load(OsuGameBase game)
+        {
+            version = game.Version;
+        }
+
+        protected override async Task<bool> PerformUpdateCheck()
+        {
+            try
+            {
+                var releases = new OsuJsonWebRequest<GitHubRelease>("https://api.github.com/repos/ppy/osu/releases/latest");
+
+                await releases.PerformAsync().ConfigureAwait(false);
+
+                var latest = releases.ResponseObject;
+
+                // avoid any discrepancies due to build suffixes for now.
+                // eventually we will want to support release streams and consider these.
+                version = version.Split('-').First();
+                string latestTagName = latest.TagName.Split('-').First();
+
+                if (latestTagName != version)
+                {
+                    Notifications.Post(new SimpleNotification
+                    {
+                        Text = $"A newer release of osu! has been found ({version} → {latestTagName}).\n\n"
+                               + "Check with your package manager / provider to bring osu! up-to-date!",
+                        Icon = FontAwesome.Solid.Upload,
+                    });
+
+                    return true;
+                }
+            }
+            catch
+            {
+                // we shouldn't crash on a web failure. or any failure for the matter.
+                return true;
+            }
+
+            return false;
+        }
+    }
+}

osu.Game/Updater/SimpleUpdateManager.cs

@@ -2,10 +2,8 @@
 // See the LICENCE file in the repository root for full licence text.
 
 using System;
-using System.Collections.Generic;
 using System.Linq;
 using System.Threading.Tasks;
-using Newtonsoft.Json;
 using osu.Framework;
 using osu.Framework.Allocation;
 using osu.Framework.Graphics.Sprites;
@@ -104,26 +102,5 @@ namespace osu.Game.Updater
 
             return bestAsset?.BrowserDownloadUrl ?? release.HtmlUrl;
         }
-
-        public class GitHubRelease
-        {
-            [JsonProperty("html_url")]
-            public string HtmlUrl { get; set; }
-
-            [JsonProperty("tag_name")]
-            public string TagName { get; set; }
-
-            [JsonProperty("assets")]
-            public List<GitHubAsset> Assets { get; set; }
-        }
-
-        public class GitHubAsset
-        {
-            [JsonProperty("name")]
-            public string Name { get; set; }
-
-            [JsonProperty("browser_download_url")]
-            public string BrowserDownloadUrl { get; set; }
-        }
     }
 }

osu.sln.DotSettings

@@ -209,6 +209,8 @@
 	<s:String x:Key="/Default/CodeInspection/Highlighting/InspectionSeverities/=StructCanBeMadeReadOnly/@EntryIndexedValue">WARNING</s:String>
 	<s:String x:Key="/Default/CodeInspection/Highlighting/InspectionSeverities/=SuggestVarOrType_005FBuiltInTypes/@EntryIndexedValue">SUGGESTION</s:String>
 	<s:String x:Key="/Default/CodeInspection/Highlighting/InspectionSeverities/=SuggestVarOrType_005FSimpleTypes/@EntryIndexedValue">DO_NOT_SHOW</s:String>
+	<s:String x:Key="/Default/CodeInspection/Highlighting/InspectionSeverities/=SuspiciousTypeConversion_002EGlobal/@EntryIndexedValue"></s:String>
+	<s:Boolean x:Key="/Default/CodeInspection/Highlighting/InspectionSeverities/=SuspiciousTypeConversion_002EGlobal/@EntryIndexRemoved">True</s:Boolean>
 	<s:String x:Key="/Default/CodeInspection/Highlighting/InspectionSeverities/=SwitchStatementMissingSomeCases/@EntryIndexedValue">DO_NOT_SHOW</s:String>
 	<s:String x:Key="/Default/CodeInspection/Highlighting/InspectionSeverities/=TabsAndSpacesMismatch/@EntryIndexedValue">WARNING</s:String>
 	<s:String x:Key="/Default/CodeInspection/Highlighting/InspectionSeverities/=TabsAreDisallowed/@EntryIndexedValue">WARNING</s:String>