Add Job info to DisassemblyDiagnoser report headers (#2884)

* "Fix unhandled exception when running invalid type-based benchmark with arguments

  Fixes #2724

  When running BenchmarkRunner.Run<T>() or BenchmarkRunner.Run(Type) with
  arguments on an invalid benchmark type (no [Benchmark] methods), the runner
  threw an unhandled InvalidOperationException instead of returning a validation error.

  Changes:
  - Replace .Single() with .SingleOrDefault() in RunWithDirtyAssemblyResolveHelper
  - Return Summary.ValidationFailed when no benchmarks are found
  - Enable and update tests for args scenarios in RunningEmptyBenchmarkTests.cs"

* Fix StyleCop SA1028: Remove trailing whitespace

* "Add assertion for failure in test per maintainer feedback"

* "Add Job info to DisassemblyDiagnoser report headers  Fixes #2573
  When using multiple coreruns, the disassembly report headers were identical, making it impossible to distinguish which assembly belongs to which corerun.
  Changes:
  - Add Job DisplayInfo to markdown header: ## {RuntimeInfo} (Job: {JobDisplayInfo})
  - Add Job info as <h3> in HTML exporter
  - Add Job info to diff exporter comparison output
  - Add tests verifying Job info is included in headers"

Author: Shrinidhi203

src/BenchmarkDotNet/Disassemblers/Exporters/GithubMarkdownDiffDisassemblyExporter.cs

@@ -90,7 +90,8 @@ private string SaveDisassemblyResult(Summary summary, DisassemblyResult disassem
             return filePath;
         }
 
-        private static string GetImportantInfo(BenchmarkReport benchmarkReport) => benchmarkReport.GetRuntimeInfo();
+        private static string GetImportantInfo(BenchmarkReport benchmarkReport) =>
+            $"{benchmarkReport.GetRuntimeInfo()} (Job: {benchmarkReport.BenchmarkCase.Job.DisplayInfo})";
 
         private static void RunGitDiff(string firstFile, string secondFile, StringBuilder result)
         {

src/BenchmarkDotNet/Disassemblers/Exporters/GithubMarkdownDisassemblyExporter.cs

@@ -26,7 +26,8 @@ public override void ExportToLog(Summary summary, ILogger logger)
         {
             foreach (var benchmarkCase in summary.BenchmarksCases.Where(results.ContainsKey))
             {
-                logger.WriteLine($"## {summary[benchmarkCase].GetRuntimeInfo()}");
+                logger.WriteLine($"## {summary[benchmarkCase].GetRuntimeInfo()} (Job: {benchmarkCase.Job.DisplayInfo})");
+                logger.WriteLine();
 
                 Export(logger, results[benchmarkCase], config);
             }

src/BenchmarkDotNet/Disassemblers/Exporters/HtmlDisassemblyExporter.cs

@@ -52,6 +52,7 @@ public override void ExportToLog(Summary summary, ILogger logger)
         private void Export(ILogger logger, Summary summary, DisassemblyResult disassemblyResult, BenchmarkCase benchmarkCase, ref int referenceIndex)
         {
             logger.WriteLine($"<h2>{summary[benchmarkCase].GetRuntimeInfo()}</h2>");
+            logger.WriteLine($"<h3>Job: {benchmarkCase.Job.DisplayInfo}</h3>");
             logger.WriteLine("<table><tbody>");
 
             int methodIndex = 0;

tests/BenchmarkDotNet.Tests/Disassemblers/GithubMarkdownDisassemblyExporterMultiCorerunTest.cs

@@ -0,0 +1,65 @@
+using System.Collections.Immutable;
+using System.Linq;
+using BenchmarkDotNet.Configs;
+using BenchmarkDotNet.Diagnosers;
+using BenchmarkDotNet.Disassemblers;
+using BenchmarkDotNet.Disassemblers.Exporters;
+using BenchmarkDotNet.Loggers;
+using BenchmarkDotNet.Tests.Mocks;
+using Xunit;
+
+namespace BenchmarkDotNet.Tests.Disassemblers
+{
+    public class GithubMarkdownDisassemblyExporterMultiCorerunTest
+    {
+        #region ExportToLog Tests
+
+        /// <summary>
+        /// Tests that GithubMarkdownDisassemblyExporter includes Job info in headers.
+        /// </summary>
+        [Fact]
+        public void ExportToLog_IncludesJobInfoInHeader()
+        {
+            // Arrange
+            var logger = new AccumulationLogger();
+            var config = new DisassemblyDiagnoserConfig();
+            var summary = MockFactory.CreateSummary(typeof(MockFactory.MockBenchmarkClass));
+            var results = summary.BenchmarksCases.ToImmutableDictionary(
+                bc => bc,
+                bc => new DisassemblyResult { Methods = new DisassembledMethod[0], Errors = new string[0] });
+            var exporter = new GithubMarkdownDisassemblyExporter(results, config);
+
+            // Act
+            exporter.ExportToLog(summary, logger);
+
+            // Assert
+            var output = logger.GetLog();
+            Assert.Contains("(Job:", output);
+        }
+
+        [Fact]
+        public void ExportToLog_FormatsHeaderWithJobDisplayInfo()
+        {
+            // Arrange
+            var logger = new AccumulationLogger();
+            var config = new DisassemblyDiagnoserConfig();
+            var summary = MockFactory.CreateSummary(typeof(MockFactory.MockBenchmarkClass));
+            var results = summary.BenchmarksCases.ToImmutableDictionary(
+                bc => bc,
+                bc => new DisassemblyResult { Methods = new DisassembledMethod[0], Errors = new string[0] });
+            var exporter = new GithubMarkdownDisassemblyExporter(results, config);
+
+            // Act
+            exporter.ExportToLog(summary, logger);
+
+            // Assert
+            var output = logger.GetLog();
+            var lines = output.Split('\n');
+            var headers = lines.Where(line => line.StartsWith("##")).ToArray();
+            Assert.NotEmpty(headers);
+            Assert.All(headers, header => Assert.Contains("(Job:", header));
+        }
+
+        #endregion
+    }
+}