fix: add some log and adjust vstest settings

Author: dupdob

src/Stryker.Core/Stryker.Core/InjectedHelpers/MutantControl.cs

@@ -1,6 +1,6 @@
 namespace Stryker
 {
-    internal static class MutantControl
+    public static class MutantControl
     {
         private static System.Collections.Generic.List<int> _coveredMutants;
         private static System.Collections.Generic.List<int> _coveredStaticdMutants;

src/Stryker.Core/Stryker.Core/TestRunners/VsTest/VsTestContextInformation.cs

@@ -252,6 +252,7 @@ private string GenerateRunSettingsForDiscovery()
  <RunConfiguration>
   <MaxCpuCount>{Math.Max(1, Options.Concurrency)}</MaxCpuCount>
   <InIsolation>true</InIsolation>
+<DisableAppDomain>true</DisableAppDomain>
   <DesignMode>true</DesignMode>
 {testCaseFilter}
  </RunConfiguration>
@@ -290,11 +291,11 @@ public string GenerateRunSettings(int? timeout, bool forCoverage, Dictionary<int
                 $@"<RunSettings>
 <RunConfiguration>
   <CollectSourceInformation>false</CollectSourceInformation>
-{(isFullFramework ? @"<DisableAppDomain>true</DisableAppDomain>
-" : string.Empty)}  <MaxCpuCount>1</MaxCpuCount>
+<MaxCpuCount>1</MaxCpuCount>
 {timeoutSettings}{settingsForCoverage}
 <DesignMode>false</DesignMode>
 <InIsolation>true</InIsolation>
+<DisableAppDomain>true</DisableAppDomain>
 {testCaseFilter}</RunConfiguration>{dataCollectorSettings}
 </RunSettings>";
 

src/Stryker.Core/Stryker.Core/TestRunners/VsTest/VsTestRunnerPool.cs

@@ -154,6 +154,12 @@ private bool ConvertSingleResult(TestResult testResult, ISet<Guid> seenTestCases
             var (key, value) = testResult.GetProperties().FirstOrDefault(x => x.Key.Id == CoverageCollector.PropertyName);
             var testCaseId = testResult.TestCase.Id;
             var unexpected = false;
+            var log = testResult.GetProperties().FirstOrDefault(x => x.Key.Id == CoverageCollector.Coveragelog).Value?.ToString();
+            if (!string.IsNullOrEmpty(log))
+            {
+                _logger.LogError($"VsTestRunner: Coverage collector error: {log}.");
+            }
+
             if (!Context.VsTests.ContainsKey(testCaseId))
             {
                 _logger.LogWarning(

src/Stryker.Core/Stryker.Core/Testing/ProcessExecutor.cs

@@ -2,7 +2,6 @@
 using System.Collections.Generic;
 using System.Diagnostics;
 using System.Diagnostics.CodeAnalysis;
-using System.IO;
 using System.Linq;
 using System.Text;
 

src/Stryker.DataCollector/Stryker.DataCollector/CoverageCollector.cs

@@ -17,6 +17,8 @@ public class CoverageCollector : InProcDataCollection
         private IDataCollectionSink _dataSink;
         private bool _coverageOn;
         private int _activeMutation = -1;
+        private bool _reportFailure;
+
         private Action<string> _logger;
         private readonly IDictionary<string, int> _mutantTestedBy = new Dictionary<string, int>();
 
@@ -34,6 +36,7 @@ public class CoverageCollector : InProcDataCollection
 
         public const string PropertyName = "Stryker.Coverage";
         public const string OutOfTestsPropertyName = "Stryker.Coverage.OutOfTests";
+        public const string Coveragelog = "CoverageLog";
 
         public string MutantList => string.Join(",", _mutantTestedBy.Values.Distinct());
 
@@ -168,12 +171,12 @@ private void ReadConfiguration(string configuration)
 
         private int GetActiveMutantForThisTest(string testId)
         {
-            if (_mutantTestedBy.ContainsKey(testId))
+            if (_mutantTestedBy.TryGetValue(testId, out var test))
             {
-                return _mutantTestedBy[testId];
+                return test;
             }
 
-            return _mutantTestedBy.ContainsKey(AnyId) ? _mutantTestedBy[AnyId] : -1;
+            return _mutantTestedBy.TryGetValue(AnyId, out var value) ? value : -1;
         }
 
         private void ParseTestMapping(XmlNodeList testMapping)
@@ -240,6 +243,11 @@ private void PublishCoverageData(DataCollectionContext dataCollectionContext)
             {
                 // no test covered any mutations, so the controller was never properly initialized
                 _dataSink.SendData(dataCollectionContext, PropertyName, ";");
+                if (!_reportFailure)
+                {
+                    _dataSink.SendData(dataCollectionContext, Coveragelog, $"Did not find type {_controlClassName}. This indicates Stryker failed to copy the mutated assembly for test.");
+                    _reportFailure = true;
+                }
                 return;
             }