Add benchmark for dependency injection.

Content.Benchmarks/DependencyInjectBenchmark.cs

@@ -0,0 +1,69 @@
+/*
+using BenchmarkDotNet.Attributes;
+using Robust.Shared.IoC;
+
+namespace Content.Benchmarks
+{
+    // To actually run this benchmark you'll have to make DependencyCollection public so it's accessible.
+
+    public class DependencyInjectBenchmark
+    {
+        [Params(InjectMode.Reflection, InjectMode.DynamicMethod)]
+        public InjectMode Mode { get; set; }
+
+        private DependencyCollection _dependencyCollection;
+
+        [GlobalSetup]
+        public void Setup()
+        {
+            _dependencyCollection = new DependencyCollection();
+            _dependencyCollection.Register<X1, X1>();
+            _dependencyCollection.Register<X2, X2>();
+            _dependencyCollection.Register<X3, X3>();
+            _dependencyCollection.Register<X4, X4>();
+            _dependencyCollection.Register<X5, X5>();
+
+            _dependencyCollection.BuildGraph();
+
+            switch (Mode)
+            {
+                case InjectMode.Reflection:
+                    break;
+                case InjectMode.DynamicMethod:
+                    // Running this without oneOff will cause DependencyCollection to cache the DynamicMethod injector.
+                    // So future injections (even with oneOff) will keep using the DynamicMethod.
+                    // AKA, be fast.
+                    _dependencyCollection.InjectDependencies(new TestDummy());
+                    break;
+            }
+        }
+
+        [Benchmark]
+        public void Inject()
+        {
+            _dependencyCollection.InjectDependencies(new TestDummy(), true);
+        }
+
+        public enum InjectMode
+        {
+            Reflection,
+            DynamicMethod
+        }
+
+        private sealed class X1 { }
+        private sealed class X2 { }
+        private sealed class X3 { }
+        private sealed class X4 { }
+        private sealed class X5 { }
+
+        private sealed class TestDummy
+        {
+            [Dependency] private readonly X1 _x1;
+            [Dependency] private readonly X2 _x2;
+            [Dependency] private readonly X3 _x3;
+            [Dependency] private readonly X4 _x4;
+            [Dependency] private readonly X5 _x5;
+        }
+    }
+}
+*/