Mimic dotnet run handling of DOTNET_ROOT in dotnet test (#50047)

Co-authored-by: Copilot <[email protected]>

Author: Youssef1313

src/Cli/dotnet/Commands/Test/Models.cs

@@ -112,7 +112,7 @@ public bool MoveNext()
 }
 
 
-internal sealed record TestModule(RunProperties RunProperties, string? ProjectFullPath, string? TargetFramework, bool IsTestingPlatformApplication, bool IsTestProject, ProjectLaunchSettingsModel? LaunchSettings, string TargetPath);
+internal sealed record TestModule(RunProperties RunProperties, string? ProjectFullPath, string? TargetFramework, bool IsTestingPlatformApplication, bool IsTestProject, ProjectLaunchSettingsModel? LaunchSettings, string TargetPath, string? DotnetRootArchVariableName);
 
 internal sealed record Handshake(Dictionary<byte, string>? Properties);
 

src/Cli/dotnet/Commands/Test/SolutionAndProjectUtility.cs

@@ -1,6 +1,7 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
+using System.CommandLine;
 using System.Diagnostics;
 using Microsoft.Build.Evaluation;
 using Microsoft.Build.Execution;
@@ -250,7 +251,17 @@ public static IEnumerable<ParallelizableTestModuleGroupWithSequentialInnerModule
         // TODO: Support --launch-profile and pass it here.
         var launchSettings = TryGetLaunchProfileSettings(Path.GetDirectoryName(projectFullPath)!, Path.GetFileNameWithoutExtension(projectFullPath), project.GetPropertyValue(ProjectProperties.AppDesignerFolder), buildOptions, profileName: null);
 
-        return new TestModule(runProperties, PathUtility.FixFilePath(projectFullPath), targetFramework, isTestingPlatformApplication, isTestProject, launchSettings, project.GetPropertyValue(ProjectProperties.TargetPath));
+        var rootVariableName = EnvironmentVariableNames.TryGetDotNetRootArchVariableName(
+            project.GetPropertyValue("RuntimeIdentifier"),
+            project.GetPropertyValue("DefaultAppHostRuntimeIdentifier"));
+
+        if (rootVariableName is not null && Environment.GetEnvironmentVariable(rootVariableName) != null)
+        {
+            // If already set, we do not override it.
+            rootVariableName = null;
+        }
+
+        return new TestModule(runProperties, PathUtility.FixFilePath(projectFullPath), targetFramework, isTestingPlatformApplication, isTestProject, launchSettings, project.GetPropertyValue(ProjectProperties.TargetPath), rootVariableName);
 
         static RunProperties GetRunProperties(ProjectInstance project, ICollection<ILogger>? loggers)
         {

src/Cli/dotnet/Commands/Test/TestApplication.cs

@@ -3,6 +3,7 @@
 
 #nullable disable
 
+using System.CommandLine;
 using System.Diagnostics;
 using System.IO.Pipes;
 using Microsoft.DotNet.Cli.Commands.Test.IPC;
@@ -62,7 +63,7 @@ private ProcessStartInfo CreateProcessStartInfo(TestOptions testOptions)
             FileName = Module.RunProperties.RunCommand,
             Arguments = GetArguments(testOptions),
             RedirectStandardOutput = true,
-            RedirectStandardError = true
+            RedirectStandardError = true,
         };
 
         if (!string.IsNullOrEmpty(Module.RunProperties.RunWorkingDirectory))
@@ -75,7 +76,7 @@ private ProcessStartInfo CreateProcessStartInfo(TestOptions testOptions)
             foreach (var entry in Module.LaunchSettings.EnvironmentVariables)
             {
                 string value = Environment.ExpandEnvironmentVariables(entry.Value);
-                processStartInfo.EnvironmentVariables[entry.Key] = value;
+                processStartInfo.Environment[entry.Key] = value;
             }
 
             if (!_buildOptions.NoLaunchProfileArguments &&
@@ -85,6 +86,11 @@ private ProcessStartInfo CreateProcessStartInfo(TestOptions testOptions)
             }
         }
 
+        if (Module.DotnetRootArchVariableName is not null)
+        {
+            processStartInfo.Environment[Module.DotnetRootArchVariableName] = Path.GetDirectoryName(new Muxer().MuxerPath);
+        }
+
         return processStartInfo;
     }
 

src/Cli/dotnet/Commands/Test/TestModulesFilterHandler.cs

@@ -58,7 +58,7 @@ public bool RunWithTestModulesFilter(ParseResult parseResult)
                 ? new RunProperties(muxerPath, $@"exec ""{testModule}""", null)
                 : new RunProperties(testModule, null, null);
 
-            var testApp = new ParallelizableTestModuleGroupWithSequentialInnerModules(new TestModule(runProperties, null, null, true, true, null, testModule));
+            var testApp = new ParallelizableTestModuleGroupWithSequentialInnerModules(new TestModule(runProperties, null, null, true, true, null, testModule, DotnetRootArchVariableName: null));
             // Write the test application to the channel
             _actionQueue.Enqueue(testApp);
         }

src/Common/EnvironmentVariableNames.cs

@@ -35,15 +35,15 @@ static class EnvironmentVariableNames
     public static string? TryGetDotNetRootVariableName(string runtimeIdentifier, string defaultAppHostRuntimeIdentifier, Version? targetFrameworkVersion)
         => TryGetDotNetRootVariableNameImpl(runtimeIdentifier, defaultAppHostRuntimeIdentifier, targetFrameworkVersion, RuntimeInformation.ProcessArchitecture, Environment.Is64BitProcess);
 
-    internal static string? TryGetDotNetRootVariableNameImpl(string runtimeIdentifier, string defaultAppHostRuntimeIdentifier, Version? targetFrameworkVersion, Architecture currentArchitecture, bool is64bit)
+    internal static string? TryGetDotNetRootVariableNameImpl(string runtimeIdentifier, string defaultAppHostRuntimeIdentifier, Version? targetFrameworkVersion, Architecture currentArchitecture, bool is64bit, bool onlyUseArchSpecific = false)
     {
         // If the app targets the same architecture as SDK is running on or an unknown architecture, set DOTNET_ROOT, DOTNET_ROOT(x86) for 32-bit, DOTNET_ROOT_arch for TFM 6+.
         // If the app targets different architecture from the SDK, do not set DOTNET_ROOT.
 
         if (!TryParseArchitecture(runtimeIdentifier, out var targetArchitecture) && !TryParseArchitecture(defaultAppHostRuntimeIdentifier, out targetArchitecture) ||
             targetArchitecture == currentArchitecture)
         {
-            var suffix = targetFrameworkVersion != null && targetFrameworkVersion >= s_version6_0 ?
+            var suffix = onlyUseArchSpecific || (targetFrameworkVersion != null && targetFrameworkVersion >= s_version6_0) ?
                 $"_{currentArchitecture.ToString().ToUpperInvariant()}" :
                 is64bit ? "" : "(x86)";
 
@@ -53,6 +53,9 @@ static class EnvironmentVariableNames
         return null;
     }
 
+    internal static string? TryGetDotNetRootArchVariableName(string runtimeIdentifier, string defaultAppHostRuntimeIdentifier)
+        => TryGetDotNetRootVariableNameImpl(runtimeIdentifier, defaultAppHostRuntimeIdentifier, null, RuntimeInformation.ProcessArchitecture, Environment.Is64BitProcess, onlyUseArchSpecific: true);
+
     internal static bool TryParseArchitecture(string runtimeIdentifier, out Architecture architecture)
     {
         // RID is [os].[version]-[architecture]-[additional qualifiers]