Add benchmark coverage of mod retrieval

osu.Game.Benchmarks/BenchmarkRuleset.cs

@@ -0,0 +1,42 @@
+// 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 BenchmarkDotNet.Attributes;
+using osu.Game.Online.API;
+using osu.Game.Rulesets.Osu;
+
+namespace osu.Game.Benchmarks
+{
+    public class BenchmarkRuleset : BenchmarkTest
+    {
+        private OsuRuleset ruleset;
+        private APIMod apiModDoubleTime;
+        private APIMod apiModDifficultyAdjust;
+
+        public override void SetUp()
+        {
+            base.SetUp();
+            ruleset = new OsuRuleset();
+            apiModDoubleTime = new APIMod { Acronym = "DT" };
+            apiModDifficultyAdjust = new APIMod { Acronym = "DA" };
+        }
+
+        [Benchmark]
+        public void BenchmarkToModDoubleTime()
+        {
+            apiModDoubleTime.ToMod(ruleset);
+        }
+
+        [Benchmark]
+        public void BenchmarkToModDifficultyAdjust()
+        {
+            apiModDifficultyAdjust.ToMod(ruleset);
+        }
+
+        [Benchmark]
+        public void BenchmarkGetAllMods()
+        {
+            ruleset.GetAllMods();
+        }
+    }
+}