less allocations

Author: lbargaoanu

src/AutoMapper/Configuration/INamingConvention.cs

@@ -1,3 +1,4 @@
+using System;
 using System.Text.RegularExpressions;
 namespace AutoMapper
 {
@@ -15,23 +16,31 @@ public interface INamingConvention
     }
     public class ExactMatchNamingConvention : INamingConvention
     {
-        public static readonly ExactMatchNamingConvention Instance = new ExactMatchNamingConvention();
+        public static readonly ExactMatchNamingConvention Instance = new();
         public Regex SplittingExpression { get; }
         public string SeparatorCharacter => "";
         public string ReplaceValue(Match match) => match.Value;
     }
     public class PascalCaseNamingConvention : INamingConvention
     {
-        private static readonly Regex PascalCase = new Regex(@"(\p{Lu}+(?=$|\p{Lu}[\p{Ll}0-9])|\p{Lu}?[\p{Ll}0-9]+)");
-        public static readonly PascalCaseNamingConvention Instance = new PascalCaseNamingConvention();
+        private static readonly Regex PascalCase = new(@"(\p{Lu}+(?=$|\p{Lu}[\p{Ll}0-9])|\p{Lu}?[\p{Ll}0-9]+)");
+        public static readonly PascalCaseNamingConvention Instance = new();
         public Regex SplittingExpression { get; } = PascalCase;
         public string SeparatorCharacter => string.Empty;
-        public string ReplaceValue(Match match) => match.Value[0].ToString().ToUpper() + match.Value.Substring(1);
+        public string ReplaceValue(Match match)
+        {
+            var source = match.Value;
+            return string.Create(source.Length, source, static (buffer, state) =>
+            {
+                buffer[0] = char.ToUpper(state[0]);
+                ((ReadOnlySpan<char>)state)[1..].CopyTo(buffer[1..]);
+            });
+        }
     }
     public class LowerUnderscoreNamingConvention : INamingConvention
     {
-        private static readonly Regex LowerUnderscore = new Regex(@"[\p{Ll}\p{Lu}0-9]+(?=_?)");
-        public static readonly LowerUnderscoreNamingConvention Instance = new LowerUnderscoreNamingConvention();
+        private static readonly Regex LowerUnderscore = new(@"[\p{Ll}\p{Lu}0-9]+(?=_?)");
+        public static readonly LowerUnderscoreNamingConvention Instance = new();
         public Regex SplittingExpression { get; } = LowerUnderscore;
         public string SeparatorCharacter => "_";
         public string ReplaceValue(Match match) => match.Value.ToLower();

src/AutoMapper/TypeMap.cs

@@ -12,7 +12,6 @@ namespace AutoMapper
     using static Execution.ExpressionBuilder;
     using Configuration;
     using Features;
-    using QueryableExtensions.Impl;
     using Internal;
     /// <summary>
     /// Main configuration object holding all mapping configuration for a source and destination type

src/Benchmark/Program.cs

@@ -1,4 +1,5 @@
-using System.Collections.Generic;
+using System;
+using System.Collections.Generic;
 using Benchmark.Flattening;
 
 namespace Benchmark
@@ -14,12 +15,16 @@ public static void Main(string[] args)
                     { "Complex", new IObjectToObjectMapper[] { new ComplexTypeMapper(), new ManualComplexTypeMapper() } },
                     { "Deep", new IObjectToObjectMapper[] { new DeepTypeMapper(), new ManualDeepTypeMapper() } }
                 };
-            foreach(var pair in mappers)
+            while (true)
             {
-                foreach(var mapper in pair.Value)
+                foreach (var pair in mappers)
                 {
-                    new BenchEngine(mapper, pair.Key).Start();
+                    foreach (var mapper in pair.Value)
+                    {
+                        new BenchEngine(mapper, pair.Key).Start();
+                    }
                 }
+                Console.ReadLine();
             }
         }
     }