Stop persisting Skills in DifficultyAttributes

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

@@ -20,7 +20,7 @@ namespace osu.Game.Rulesets.EmptyFreeform
 
         protected override DifficultyAttributes CreateDifficultyAttributes(IBeatmap beatmap, Mod[] mods, Skill[] skills, double clockRate)
         {
-            return new DifficultyAttributes(mods, skills, 0);
+            return new DifficultyAttributes(mods, 0);
         }
 
         protected override IEnumerable<DifficultyHitObject> CreateDifficultyHitObjects(IBeatmap beatmap, double clockRate) => Enumerable.Empty<DifficultyHitObject>();

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

@@ -20,7 +20,7 @@ namespace osu.Game.Rulesets.Pippidon
 
         protected override DifficultyAttributes CreateDifficultyAttributes(IBeatmap beatmap, Mod[] mods, Skill[] skills, double clockRate)
         {
-            return new DifficultyAttributes(mods, skills, 0);
+            return new DifficultyAttributes(mods, 0);
         }
 
         protected override IEnumerable<DifficultyHitObject> CreateDifficultyHitObjects(IBeatmap beatmap, double clockRate) => Enumerable.Empty<DifficultyHitObject>();

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

@@ -20,7 +20,7 @@ namespace osu.Game.Rulesets.EmptyScrolling
 
         protected override DifficultyAttributes CreateDifficultyAttributes(IBeatmap beatmap, Mod[] mods, Skill[] skills, double clockRate)
         {
-            return new DifficultyAttributes(mods, skills, 0);
+            return new DifficultyAttributes(mods, 0);
         }
 
         protected override IEnumerable<DifficultyHitObject> CreateDifficultyHitObjects(IBeatmap beatmap, double clockRate) => Enumerable.Empty<DifficultyHitObject>();

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

@@ -20,7 +20,7 @@ namespace osu.Game.Rulesets.Pippidon
 
         protected override DifficultyAttributes CreateDifficultyAttributes(IBeatmap beatmap, Mod[] mods, Skill[] skills, double clockRate)
         {
-            return new DifficultyAttributes(mods, skills, 0);
+            return new DifficultyAttributes(mods, 0);
         }
 
         protected override IEnumerable<DifficultyHitObject> CreateDifficultyHitObjects(IBeatmap beatmap, double clockRate) => Enumerable.Empty<DifficultyHitObject>();

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

@@ -31,7 +31,7 @@ namespace osu.Game.Rulesets.Catch.Difficulty
         protected override DifficultyAttributes CreateDifficultyAttributes(IBeatmap beatmap, Mod[] mods, Skill[] skills, double clockRate)
         {
             if (beatmap.HitObjects.Count == 0)
-                return new CatchDifficultyAttributes { Mods = mods, Skills = skills };
+                return new CatchDifficultyAttributes { Mods = mods };
 
             // this is the same as osu!, so there's potential to share the implementation... maybe
             double preempt = IBeatmapDifficultyInfo.DifficultyRange(beatmap.Difficulty.ApproachRate, 1800, 1200, 450) / clockRate;
@@ -42,7 +42,6 @@ namespace osu.Game.Rulesets.Catch.Difficulty
                 Mods = mods,
                 ApproachRate = preempt > 1200.0 ? -(preempt - 1800.0) / 120.0 : -(preempt - 1200.0) / 150.0 + 5.0,
                 MaxCombo = beatmap.HitObjects.Count(h => h is Fruit) + beatmap.HitObjects.OfType<JuiceStream>().SelectMany(j => j.NestedHitObjects).Count(h => !(h is TinyDroplet)),
-                Skills = skills
             };
         }
 

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

@@ -39,7 +39,7 @@ namespace osu.Game.Rulesets.Mania.Difficulty
         protected override DifficultyAttributes CreateDifficultyAttributes(IBeatmap beatmap, Mod[] mods, Skill[] skills, double clockRate)
         {
             if (beatmap.HitObjects.Count == 0)
-                return new ManiaDifficultyAttributes { Mods = mods, Skills = skills };
+                return new ManiaDifficultyAttributes { Mods = mods };
 
             HitWindows hitWindows = new ManiaHitWindows();
             hitWindows.SetDifficulty(beatmap.Difficulty.OverallDifficulty);
@@ -51,7 +51,6 @@ namespace osu.Game.Rulesets.Mania.Difficulty
                 GreatHitWindow = Math.Ceiling(getHitWindow300(mods) / clockRate),
                 ScoreMultiplier = getScoreMultiplier(mods),
                 MaxCombo = beatmap.HitObjects.Sum(h => h is HoldNote ? 2 : 1),
-                Skills = skills
             };
         }
 

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

@@ -31,7 +31,7 @@ namespace osu.Game.Rulesets.Osu.Difficulty
         protected override DifficultyAttributes CreateDifficultyAttributes(IBeatmap beatmap, Mod[] mods, Skill[] skills, double clockRate)
         {
             if (beatmap.HitObjects.Count == 0)
-                return new OsuDifficultyAttributes { Mods = mods, Skills = skills };
+                return new OsuDifficultyAttributes { Mods = mods };
 
             double aimRating = Math.Sqrt(skills[0].DifficultyValue()) * difficulty_multiplier;
             double aimRatingNoSliders = Math.Sqrt(skills[1].DifficultyValue()) * difficulty_multiplier;
@@ -85,7 +85,6 @@ namespace osu.Game.Rulesets.Osu.Difficulty
                 HitCircleCount = hitCirclesCount,
                 SliderCount = sliderCount,
                 SpinnerCount = spinnerCount,
-                Skills = skills
             };
         }
 

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

@@ -65,7 +65,7 @@ namespace osu.Game.Rulesets.Taiko.Difficulty
         protected override DifficultyAttributes CreateDifficultyAttributes(IBeatmap beatmap, Mod[] mods, Skill[] skills, double clockRate)
         {
             if (beatmap.HitObjects.Count == 0)
-                return new TaikoDifficultyAttributes { Mods = mods, Skills = skills };
+                return new TaikoDifficultyAttributes { Mods = mods };
 
             var colour = (Colour)skills[0];
             var rhythm = (Rhythm)skills[1];
@@ -96,7 +96,6 @@ namespace osu.Game.Rulesets.Taiko.Difficulty
                 ColourStrain = colourRating,
                 GreatHitWindow = hitWindows.WindowFor(HitResult.Great) / clockRate,
                 MaxCombo = beatmap.HitObjects.Count(h => h is Hit),
-                Skills = skills
             };
         }
 

osu.Game/Rulesets/Difficulty/DifficultyAttributes.cs

@@ -4,7 +4,6 @@
 using System.Collections.Generic;
 using System.Linq;
 using Newtonsoft.Json;
-using osu.Game.Rulesets.Difficulty.Skills;
 using osu.Game.Rulesets.Mods;
 
 namespace osu.Game.Rulesets.Difficulty
@@ -31,11 +30,6 @@ namespace osu.Game.Rulesets.Difficulty
         /// </summary>
         public Mod[] Mods { get; set; }
 
-        /// <summary>
-        /// The skills resulting from the difficulty calculation.
-        /// </summary>
-        public Skill[] Skills { get; set; }
-
         /// <summary>
         /// The combined star rating of all skill.
         /// </summary>
@@ -59,12 +53,10 @@ namespace osu.Game.Rulesets.Difficulty
         /// Creates new <see cref="DifficultyAttributes"/>.
         /// </summary>
         /// <param name="mods">The mods which were applied to the beatmap.</param>
-        /// <param name="skills">The skills resulting from the difficulty calculation.</param>
         /// <param name="starRating">The combined star rating of all skills.</param>
-        public DifficultyAttributes(Mod[] mods, Skill[] skills, double starRating)
+        public DifficultyAttributes(Mod[] mods, double starRating)
         {
             Mods = mods;
-            Skills = skills;
             StarRating = starRating;
         }