Move diagnoser source generation to CodeGenerator.

Author: timcassell

src/BenchmarkDotNet/Code/CodeGenerator.cs

@@ -7,6 +7,7 @@
 using System.Text;
 using System.Threading.Tasks;
 using BenchmarkDotNet.Characteristics;
+using BenchmarkDotNet.Diagnosers;
 using BenchmarkDotNet.Disassemblers;
 using BenchmarkDotNet.Environments;
 using BenchmarkDotNet.Extensions;
@@ -66,7 +67,7 @@ internal static string Generate(BuildPartition buildPartition)
                     .Replace("$MeasureExtraStats$", buildInfo.Config.HasExtraStatsDiagnoser() ? "true" : "false")
                     .Replace("$DisassemblerEntryMethodName$", DisassemblerConstants.DisassemblerEntryMethodName)
                     .Replace("$WorkloadMethodCall$", provider.GetWorkloadMethodCall(passArguments))
-                    .Replace("$InProcessDiagnosers$", string.Join($",\n", buildInfo.CompositeInProcessDiagnoser.GetSourceCode(benchmark)))
+                    .Replace("$InProcessDiagnoserRouters$", GetInProcessDiagnoserRouters(buildInfo))
                     .RemoveRedundantIfDefines(compilationId);
 
                 benchmarkTypeCode = Unroll(benchmarkTypeCode, benchmark.Job.ResolveValue(RunMode.UnrollFactorCharacteristic, EnvironmentResolver.Instance));
@@ -250,6 +251,31 @@ private static string GetEngineFactoryTypeName(BenchmarkCase benchmarkCase)
             return factoryType.GetCorrectCSharpTypeName();
         }
 
+        private static string GetInProcessDiagnoserRouters(BenchmarkBuildInfo buildInfo)
+        {
+            var sourceCodes = buildInfo.CompositeInProcessDiagnoser.InProcessDiagnosers
+                .Select((d, i) => ToSourceCode(d, buildInfo.BenchmarkCase, i))
+                .WhereNotNull();
+            return string.Join($",\n", sourceCodes);
+
+            static string? ToSourceCode(IInProcessDiagnoser diagnoser, BenchmarkCase benchmarkCase, int index)
+            {
+                var (handlerType, serializedConfig) = diagnoser.GetSeparateProcessHandlerTypeAndSerializedConfig(benchmarkCase);
+                if (handlerType is null)
+                {
+                    return null;
+                }
+                string routerType = typeof(InProcessDiagnoserRouter).GetCorrectCSharpTypeName();
+                return $$"""
+                new {{routerType}}() {
+                    {{nameof(InProcessDiagnoserRouter.handler)}} = {{routerType}}.{{nameof(InProcessDiagnoserRouter.Init)}}(new {{handlerType.GetCorrectCSharpTypeName()}}(), {{SourceCodeHelper.ToSourceCode(serializedConfig)}}),
+                    {{nameof(InProcessDiagnoserRouter.index)}} = {{index}},
+                    {{nameof(InProcessDiagnoserRouter.runMode)}} = {{SourceCodeHelper.ToSourceCode(diagnoser.GetRunMode(benchmarkCase))}}
+                }
+                """;
+            }
+        }
+
         private static string GetParameterModifier(ParameterInfo parameterInfo)
         {
             if (!parameterInfo.ParameterType.IsByRef)

src/BenchmarkDotNet/Diagnosers/CompositeDiagnoser.cs

@@ -63,40 +63,10 @@ public sealed class CompositeInProcessDiagnoser(IReadOnlyList<IInProcessDiagnose
         public const string HeaderKey = "// InProcessDiagnoser";
         public const string ResultsKey = $"{HeaderKey}Results";
 
-        public IEnumerable<string> GetSourceCode(BenchmarkCase benchmarkCase)
-            => inProcessDiagnosers
-                .Select((d, i) => ToSourceCode(d, benchmarkCase, i))
-                .WhereNotNull();
-
-        public IEnumerable<InProcessDiagnoserRouter> GetInProcessDiagnoserRouters(BenchmarkCase benchmarkCase)
-            => inProcessDiagnosers
-                .Select((d, i) => new InProcessDiagnoserRouter()
-                {
-                    index = i,
-                    runMode = d.GetRunMode(benchmarkCase),
-                    handler = d.GetSameProcessHandler(benchmarkCase)
-                })
-                .Where(r => r.handler != null);
+        public IReadOnlyList<IInProcessDiagnoser> InProcessDiagnosers { get; } = inProcessDiagnosers;
 
         public void DeserializeResults(int index, BenchmarkCase benchmarkCase, string results)
-            => inProcessDiagnosers[index].DeserializeResults(benchmarkCase, results);
-
-        private static string? ToSourceCode(IInProcessDiagnoser diagnoser, BenchmarkCase benchmarkCase, int index)
-        {
-            var (handlerType, serializedConfig) = diagnoser.GetSeparateProcessHandlerTypeAndSerializedConfig(benchmarkCase);
-            if (handlerType is null)
-            {
-                return null;
-            }
-            string routerType = typeof(InProcessDiagnoserRouter).GetCorrectCSharpTypeName();
-            return $$"""
-                new {{routerType}}() {
-                    {{nameof(InProcessDiagnoserRouter.handler)}} = {{routerType}}.{{nameof(InProcessDiagnoserRouter.Init)}}(new {{handlerType.GetCorrectCSharpTypeName()}}(), {{SourceCodeHelper.ToSourceCode(serializedConfig)}}),
-                    {{nameof(InProcessDiagnoserRouter.index)}} = {{index}},
-                    {{nameof(InProcessDiagnoserRouter.runMode)}} = {{SourceCodeHelper.ToSourceCode(diagnoser.GetRunMode(benchmarkCase))}}
-                }
-                """;
-        }
+            => InProcessDiagnosers[index].DeserializeResults(benchmarkCase, results);
     }
 
     [UsedImplicitly]

src/BenchmarkDotNet/Templates/BenchmarkType.txt

@@ -23,7 +23,7 @@
 
             BenchmarkDotNet.Diagnosers.CompositeInProcessDiagnoserHandler compositeInProcessDiagnoserHandler = new BenchmarkDotNet.Diagnosers.CompositeInProcessDiagnoserHandler(
                 new BenchmarkDotNet.Diagnosers.InProcessDiagnoserRouter[] {
-                    $InProcessDiagnosers$
+                    $InProcessDiagnoserRouters$
                 },
                 host,
                 diagnoserRunMode,

src/BenchmarkDotNet/Toolchains/InProcess/Emit/Implementation/Runnable/RunnableReuse.cs

@@ -29,7 +29,15 @@ public static (Job, EngineParameters, IEngineFactory) PrepareForRun<T>(T instanc
                 return (null, null, null);
 
             var compositeInProcessDiagnoserHandler = new CompositeInProcessDiagnoserHandler(
-                    [..parameters.CompositeInProcessDiagnoser.GetInProcessDiagnoserRouters(benchmarkCase)],
+                    parameters.CompositeInProcessDiagnoser.InProcessDiagnosers
+                        .Select((d, i) => new InProcessDiagnoserRouter()
+                        {
+                            index = i,
+                            runMode = d.GetRunMode(benchmarkCase),
+                            handler = d.GetSameProcessHandler(benchmarkCase)
+                        })
+                        .Where(r => r.handler != null)
+                        .ToArray(),
                     host,
                     parameters.DiagnoserRunMode,
                     new InProcessDiagnoserActionArgs(instance)

src/BenchmarkDotNet/Toolchains/InProcess/NoEmit/InProcessNoEmitRunner.cs

@@ -1,5 +1,6 @@
 using System;
 using System.Diagnostics.CodeAnalysis;
+using System.Linq;
 using System.Reflection;
 using BenchmarkDotNet.Engines;
 using BenchmarkDotNet.Environments;
@@ -132,7 +133,15 @@ public static void RunCore(IHost host, ExecuteParameters parameters)
                 host.WriteLine();
 
                 var compositeInProcessDiagnoserHandler = new Diagnosers.CompositeInProcessDiagnoserHandler(
-                    [..parameters.CompositeInProcessDiagnoser.GetInProcessDiagnoserRouters(benchmarkCase)],
+                    [..parameters.CompositeInProcessDiagnoser.InProcessDiagnosers
+                        .Select((d, i) => new Diagnosers.InProcessDiagnoserRouter()
+                        {
+                            index = i,
+                            runMode = d.GetRunMode(benchmarkCase),
+                            handler = d.GetSameProcessHandler(benchmarkCase)
+                        })
+                        .Where(r => r.handler != null)
+                        .ToArray()],
                     host,
                     parameters.DiagnoserRunMode,
                     new Diagnosers.InProcessDiagnoserActionArgs(instance)