Fix problems in assemlby loading

Author: CharliePoole

src/NUnitEngine/nunit.engine.core.tests/DotNetHelperTests.cs

@@ -63,7 +63,7 @@ public static void CanParseInputLine(string line, string name, string packageVer
         [TestCase("Microsoft.NETCore.App", "8.0.0", "8.0.22")]
         [TestCase("Microsoft.NETCore.App", "8.0.0.0", "8.0.22")]
         [TestCase("Microsoft.NETCore.App", "8.0.0.100", "8.0.22")]
-        [TestCase("Microsoft.NETCore.App", "8.0.100", "9.0.11")]
+        [TestCase("Microsoft.NETCore.App", "8.0.100", "8.0.22")]
         [TestCase("Microsoft.AspNetCore.App", "5.0.0", "8.0.22")] // Rather than 8.0.2
         [TestCase("Microsoft.AspNetCore.App", "7.0.0", "8.0.22")] // Rather than 8.0.2
         [TestCase("Microsoft.AspNetCore.App", "8.0.0", "8.0.22")] // Rather than 8.0.2

src/NUnitEngine/nunit.engine.core/DotNetHelper.cs

@@ -153,7 +153,8 @@ internal static bool FindBestRuntime(Version targetVersion, IEnumerable<RuntimeI
 
             foreach (var candidate in availableRuntimes)
             {
-                if (candidate.Version >= targetVersion)
+                if (candidate.Version.Major > targetVersion.Major ||
+                    candidate.Version.Major == targetVersion.Major && candidate.Version.Minor >= candidate.Version.Minor)
                     if (bestRuntime is null || candidate.Version.Major == bestRuntime.Version.Major)
                         bestRuntime = candidate;
             }

src/NUnitEngine/nunit.engine.core/Drivers/NUnitNetCore31Driver.cs

@@ -1,5 +1,7 @@
 // Copyright (c) Charlie Poole, Rob Prouse and Contributors. MIT License - see LICENSE.txt
 
+//#define USE_DEFAULT_ASSEMBLY_LOAD_CONTEXT
+
 #if NETCOREAPP3_1_OR_GREATER
 using System;
 using System.Linq;
@@ -66,11 +68,19 @@ public string Load(string assemblyPath, IDictionary<string, object> settings)
                 _testAssembly = AssemblyHelper.FindLoadedAssemblyByPath(assemblyPath);
 
                 if (_testAssembly != null)
+                {
                     _assemblyLoadContext = AssemblyLoadContext.GetLoadContext(_testAssembly);
+                    log.Debug($"  Already loaded in context {_assemblyLoadContext}");
+                }
                 else
                 {
+#if USE_DEFAULT_ASSEMBLY_LOAD_CONTEXT
+                    _assemblyLoadContext = AssemblyLoadContext.Default;
+#else
                     _assemblyLoadContext = new AssemblyLoadContext(Path.GetFileNameWithoutExtension(assemblyPath));
+#endif
                     _testAssembly = _assemblyLoadContext.LoadFromAssemblyPath(assemblyPath);
+                    log.Debug($"  Loaded into new context {_assemblyLoadContext}");
                 }
 
                 _testAssemblyResolver = new TestAssemblyResolver(_assemblyLoadContext, assemblyPath);
@@ -115,11 +125,6 @@ public string Load(string assemblyPath, IDictionary<string, object> settings)
             return ExecuteMethod(LOAD_METHOD) as string;
         }
 
-        private Assembly _assemblyLoadContext_Resolving(AssemblyLoadContext arg1, AssemblyName arg2)
-        {
-            throw new NotImplementedException();
-        }
-
         /// <summary>
         /// Counts the number of test cases for the loaded test assembly
         /// </summary>

src/NUnitEngine/nunit.engine.core/Internal/AssemblyHelper.cs

@@ -1,6 +1,7 @@
 // Copyright (c) Charlie Poole, Rob Prouse and Contributors. MIT License - see LICENSE.txt
 
 using System;
+using System.Diagnostics;
 using System.IO;
 using System.Linq;
 using System.Reflection;
@@ -86,14 +87,5 @@ public static Assembly FindLoadedAssemblyByPath(string assemblyPath)
                     !string.IsNullOrEmpty(a.Location) &&
                     StringComparer.OrdinalIgnoreCase.Equals(Path.GetFullPath(a.Location), full));
         }
-
-        public static Assembly FindLoadedAssemblyByName(AssemblyName assemblyName)
-        {
-            return AppDomain.CurrentDomain.GetAssemblies()
-                .FirstOrDefault(a =>
-                    !a.IsDynamic &&
-                    !string.IsNullOrEmpty(a.Location) &&
-                    a.GetName() == assemblyName);
-        }
     }
 }

src/NUnitEngine/nunit.engine.core/Internal/TestAssemblyResolver.cs

@@ -6,6 +6,7 @@
 using Microsoft.Extensions.DependencyModel.Resolution;
 using System;
 using System.Collections.Generic;
+using System.Diagnostics;
 using System.IO;
 using System.Linq;
 using System.Reflection;
@@ -52,7 +53,7 @@ private void InitializeResolutionStrategies(AssemblyLoadContext loadContext, str
             foreach (var reference in assemblyDef.MainModule.GetTypeReferences())
             {
                 string fn = reference.FullName;
-                if (fn.StartsWith("System.Windows.") || fn.StartsWith("PresentationFramework"))
+                if (fn.StartsWith("System.Windows.") || fn.StartsWith("PresentationFramework") || fn == "WindowsBase")
                     tryWindowsDesktopFirst = true;
                 if (fn.StartsWith("Microsoft.AspNetCore."))
                     tryAspNetCoreFirst = true;
@@ -81,25 +82,18 @@ public void Dispose()
             _loadContext.Resolving -= OnResolving;
         }
 
-        //public Assembly Resolve(AssemblyLoadContext context, AssemblyName assemblyName)
-        //{
-        //    return OnResolving(context, assemblyName);
-        //}
-
         private Assembly OnResolving(AssemblyLoadContext loadContext, AssemblyName assemblyName)
         {
-            if (loadContext == null) throw new ArgumentNullException("context");
-
-            //var runtimeResolverPath = _assemblyDependencyResolver.ResolveAssemblyToPath(assemblyName);
-            //if (!string.IsNullOrEmpty(runtimeResolverPath) && File.Exists(runtimeResolverPath))
-            //{
-            //    var loadedAssembly = _loadContext.LoadFromAssemblyPath(runtimeResolverPath);
-            //    if (loadedAssembly != null)
-            //    {
-            //        log.Info($"Assembly {assemblyName} ({loadedAssembly}) is loaded using the deps.json info");
-            //        return loadedAssembly;
-            //    }
-            //}
+            var runtimeResolverPath = _assemblyDependencyResolver.ResolveAssemblyToPath(assemblyName);
+            if (!string.IsNullOrEmpty(runtimeResolverPath) && File.Exists(runtimeResolverPath))
+            {
+                var loadedAssembly = _loadContext.LoadFromAssemblyPath(runtimeResolverPath);
+                if (loadedAssembly != null)
+                {
+                    log.Info($"Assembly {assemblyName} ({loadedAssembly}) is loaded using the deps.json info");
+                    return loadedAssembly;
+                }
+            }
 
             foreach (var strategy in ResolutionStrategies)
                 if (strategy.TryToResolve(loadContext, assemblyName, out Assembly loadedAssembly))