Remove unused class, consolidate diagnosers, and add SeparateLogic tests

Co-authored-by: timcassell <35501420+timcassell@users.noreply.github.com>

Author: Copilot

tests/BenchmarkDotNet.IntegrationTests/Diagnosers/MockInProcessDiagnoser.cs

@@ -70,7 +70,7 @@ public sealed class MockInProcessDiagnoser : BaseMockInProcessDiagnoser
 {
     public override string DiagnoserName => nameof(MockInProcessDiagnoser);
     public override RunMode DiagnoserRunMode => RunMode.NoOverhead;
-    public override string ExpectedResult => "MockResult";
+    public override string ExpectedResult => "NoOverheadResult";
 
     public override (Type? handlerType, string? serializedConfig) GetSeparateProcessHandlerTypeAndSerializedConfig(BenchmarkCase benchmarkCase)
         => (typeof(MockInProcessDiagnoserHandler), ExpectedResult);
@@ -80,20 +80,6 @@ public sealed class MockInProcessDiagnoserHandler : BaseMockInProcessDiagnoserHa
 {
 }
 
-public sealed class MockInProcessDiagnoserNoOverhead : BaseMockInProcessDiagnoser
-{
-    public override string DiagnoserName => nameof(MockInProcessDiagnoserNoOverhead);
-    public override RunMode DiagnoserRunMode => RunMode.NoOverhead;
-    public override string ExpectedResult => "NoOverheadResult";
-
-    public override (Type? handlerType, string? serializedConfig) GetSeparateProcessHandlerTypeAndSerializedConfig(BenchmarkCase benchmarkCase)
-        => (typeof(MockInProcessDiagnoserNoOverheadHandler), ExpectedResult);
-}
-
-public sealed class MockInProcessDiagnoserNoOverheadHandler : BaseMockInProcessDiagnoserHandler
-{
-}
-
 public sealed class MockInProcessDiagnoserExtraRun : BaseMockInProcessDiagnoser
 {
     public override string DiagnoserName => nameof(MockInProcessDiagnoserExtraRun);
@@ -123,4 +109,17 @@ public override (Type? handlerType, string? serializedConfig) GetSeparateProcess
 
 public sealed class MockInProcessDiagnoserNoneHandler : BaseMockInProcessDiagnoserHandler
 {
+}
+
+public sealed class MockInProcessDiagnoserSeparateLogic : BaseMockInProcessDiagnoser
+{
+    public override string DiagnoserName => nameof(MockInProcessDiagnoserSeparateLogic);
+    public override RunMode DiagnoserRunMode => RunMode.SeparateLogic;
+    public override string ExpectedResult => "SeparateLogicResult";
+
+    public override (Type? handlerType, string? serializedConfig) GetSeparateProcessHandlerTypeAndSerializedConfig(BenchmarkCase benchmarkCase)
+        => default; // SeparateLogic uses its own logic, not in-process handlers
+
+    public override IInProcessDiagnoserHandler? GetSameProcessHandler(BenchmarkCase benchmarkCase)
+        => null; // SeparateLogic uses its own logic, not in-process handlers
 }

tests/BenchmarkDotNet.IntegrationTests/MultipleInProcessDiagnosersTests.cs

@@ -21,7 +21,7 @@ public class MultipleInProcessDiagnosersTests : BenchmarkTestExecutor
 {
     public MultipleInProcessDiagnosersTests(ITestOutputHelper output) : base(output) { }
 
-    private static readonly RunMode[] AllRunModes = { RunMode.NoOverhead, RunMode.ExtraRun, RunMode.None };
+    private static readonly RunMode[] AllRunModes = { RunMode.NoOverhead, RunMode.ExtraRun, RunMode.None, RunMode.SeparateLogic };
 
     private static IEnumerable<BaseMockInProcessDiagnoser[]> GetDiagnoserCombinations(int count)
     {
@@ -61,9 +61,10 @@ private static BaseMockInProcessDiagnoser CreateDiagnoser(RunMode runMode, int i
     {
         return runMode switch
         {
-            RunMode.NoOverhead => index == 0 ? new MockInProcessDiagnoserNoOverhead() : new MockInProcessDiagnoser(),
+            RunMode.NoOverhead => new MockInProcessDiagnoser(),
             RunMode.ExtraRun => new MockInProcessDiagnoserExtraRun(),
             RunMode.None => new MockInProcessDiagnoserNone(),
+            RunMode.SeparateLogic => new MockInProcessDiagnoserSeparateLogic(),
             _ => throw new ArgumentException($"Unsupported run mode: {runMode}")
         };
     }
@@ -107,7 +108,8 @@ public void MultipleInProcessDiagnosersWork(BaseMockInProcessDiagnoser[] diagnos
 
         foreach (var diagnoser in diagnosers)
         {
-            bool shouldHaveResults = diagnoser.DiagnoserRunMode != RunMode.None;
+            // Only NoOverhead and ExtraRun run modes should collect results via in-process handlers
+            bool shouldHaveResults = diagnoser.DiagnoserRunMode == RunMode.NoOverhead || diagnoser.DiagnoserRunMode == RunMode.ExtraRun;
 
             if (shouldHaveResults)
             {
@@ -146,27 +148,4 @@ public void BenchmarkMethod()
             Interlocked.Increment(ref counter);
         }
     }
-
-    public class MultipleBenchmarks
-    {
-        private int counter;
-
-        [Benchmark]
-        public void Benchmark1()
-        {
-            Interlocked.Increment(ref counter);
-        }
-
-        [Benchmark]
-        public void Benchmark2()
-        {
-            Interlocked.Increment(ref counter);
-        }
-
-        [Benchmark]
-        public void Benchmark3()
-        {
-            Interlocked.Increment(ref counter);
-        }
-    }
 }