Migrate test suite to xUnit v3 on Microsoft.Testing.Platform

eng/InstallRuntimes.proj

@@ -63,7 +63,7 @@
 
   <Target Name="InstallTestRuntimes"
           AfterTargets="Build"
-          DependsOnTargets="CleanupVersionManifest;InstallRuntimesWindows;InstallRuntimesUnix;InstallBuildSdk;OverrideLatestRuntime;WriteTestVersionManifest" />
+          DependsOnTargets="CleanupVersionManifest;InstallRuntimesWindows;InstallRuntimesUnix;InstallHostRuntimeX86;InstallBuildSdk;OverrideLatestRuntime;WriteTestVersionManifest" />
 
 <!--
     When cross-building (host arch != target arch), install a host-architecture SDK
@@ -85,6 +85,24 @@
           IgnoreStandardErrorWarningFormat="true" />
   </Target>
 
+<!--
+    Stage the x86 host shared framework so the xUnit v3 / MTP test executable can start on the
+    Windows x86 test leg. Arcade's XUnitV3 RunTests target launches each test exe with
+    DOTNET_ROOT_X86=$(TestDotNetRoot)x86 (== $(ArtifactsDotnetTestDir)x86). A 32-bit apphost
+    reads DOTNET_ROOT_X86 before DOTNET_ROOT and does not fall back if it is set, so the x86
+    runtime must live in that subdirectory. The rest of the x86 install (SDK + all
+    RuntimeTestVersions) stays at the $(ArtifactsDotnetTestDir) root, where debuggees resolve it
+    via DotNetRoot. This replaces the global.json tools.runtimes.dotnet/x86 entry that used to
+    stage the same x86 shared framework into .dotnet.
+-->
+
+  <Target Name="InstallHostRuntimeX86"
+          Condition="'$(TargetArch)' == 'x86' and $([MSBuild]::IsOsPlatform(Windows)) and !Exists('$(DotNetInstallRoot)x86\shared\Microsoft.NETCore.App\$(MicrosoftNETCoreApp100Version)')">
+
+    <Exec Command="$(PowershellWrapper) &quot;&amp; { &amp;$(DotnetInstallScriptCmd) -NoPath -SkipNonVersionedFiles -Architecture x86 -Runtime dotnet -Version $(MicrosoftNETCoreApp100Version) -InstallDir $(DotNetInstallRoot)x86 }&quot;"
+          IgnoreStandardErrorWarningFormat="true" />
+  </Target>
+
 <!--
     Installs the test runtimes on Windows
 -->

eng/build.ps1

@@ -114,14 +114,27 @@ if ($test) {
             $env:SOS_TEST_INTERPRETER="true"
         }
 
-        # Build the test filter argument if provided
-        # Use backslash-escaped quotes so they survive the additional quoting in tools.ps1
+        # Build the test filter argument if provided.
+        # Tests run as xUnit v3 / Microsoft.Testing.Platform executables, so use the MTP
+        # filter options (--filter-method / --filter-class) instead of the old xunit.console
+        # -method / -class flags.
+        # Use backslash-escaped quotes so they survive the additional quoting in tools.ps1.
+        #
+        # A filter is applied to EVERY project in the test traversal, so projects that don't
+        # contain a matching test legitimately run zero tests. MTP returns exit code 8 ("zero
+        # tests ran") in that case, which Arcade would otherwise treat as a failure. Append
+        # --ignore-exit-code 8 so those non-matching projects don't fail the run. The trade-off
+        # (a mistyped filter that matches nothing anywhere would pass silently) is covered by the
+        # "at least one test ran" guard after the test run below.
+        $testFilterActive = $false
         $testFilterArg = ''
         if ($methodfilter -ne '') {
-            $testFilterArg = "/p:TestRunnerAdditionalArguments=\`"-method $methodfilter\`""
+            $testFilterActive = $true
+            $testFilterArg = "/p:TestRunnerAdditionalArguments=\`"--filter-method $methodfilter --ignore-exit-code 8\`""
         }
         elseif ($classfilter -ne '') {
-            $testFilterArg = "/p:TestRunnerAdditionalArguments=\`"-class $classfilter\`""
+            $testFilterActive = $true
+            $testFilterArg = "/p:TestRunnerAdditionalArguments=\`"--filter-class $classfilter --ignore-exit-code 8\`""
         }
 
         # When the managed build was skipped (e.g. the test-only CI legs that download prebuilt
@@ -146,6 +159,17 @@ if ($test) {
             }
         }
 
+        # When a filter is active it is applied to every project in the traversal, so non-matching
+        # projects run zero tests. --ignore-exit-code 8 (added to $testFilterArg above) keeps those
+        # from failing the run; to still catch a filter that matches nothing ANYWHERE, count the
+        # tests that ran after the build. Clear this run's result XMLs first so the post-run count
+        # only reflects the current run (result file names embed the target framework, so stale
+        # files from a previous run would not otherwise be overwritten).
+        $resultsDir = Join-Path (Join-Path $artifactsdir "TestResults") $configuration
+        if ($testFilterActive -and (Test-Path $resultsDir)) {
+            Remove-Item (Join-Path $resultsDir "*.xml") -Force -ErrorAction SilentlyContinue
+        }
+
         & "$engroot\common\build.ps1" `
           -test `
           -restore:$skipmanaged `
@@ -167,5 +191,26 @@ if ($test) {
         if ($lastExitCode -ne 0) {
             exit $lastExitCode
         }
+
+        # Guard against a filter that silently matches nothing (see note above): sum the test
+        # counts from the xUnit result XMLs this run produced and fail if nothing ran.
+        if ($testFilterActive) {
+            $testsRan = 0
+            if (Test-Path $resultsDir) {
+                foreach ($xml in Get-ChildItem $resultsDir -Filter *.xml -File -ErrorAction SilentlyContinue) {
+                    try {
+                        [xml]$doc = Get-Content -LiteralPath $xml.FullName -Raw
+                        foreach ($asm in @($doc.assemblies.assembly)) {
+                            if ($asm -and $asm.total) { $testsRan += [int]$asm.total }
+                        }
+                    } catch { }
+                }
+            }
+            if ($testsRan -eq 0) {
+                Write-Host "ERROR: The test filter matched zero tests across all projects. Check the -methodfilter/-classfilter value." -ForegroundColor Red
+                exit 1
+            }
+            Write-Host "Test filter matched $testsRan test(s) across the run." -ForegroundColor Green
+        }
     }
 }

eng/build.sh

@@ -108,12 +108,12 @@ handle_arguments() {
             ;;
 
         methodfilter|-methodfilter)
-            __TestFilter="-method $2"
+            __TestFilter="--filter-method $2"
             __ShiftArgs=1
             ;;
 
         classfilter|-classfilter)
-            __TestFilter="-class $2"
+            __TestFilter="--filter-class $2"
             __ShiftArgs=1
             ;;
 
@@ -347,10 +347,19 @@ if [[ "$__Test" == 1 ]]; then
           export SOS_TEST_INTERPRETER="true"
       fi
 
-      # Build the test filter argument if provided
+      # Build the test filter argument if provided.
+      #
+      # A filter is applied to EVERY project in the test traversal, so projects that don't
+      # contain a matching test legitimately run zero tests. MTP returns exit code 8 ("zero
+      # tests ran") in that case, which Arcade would otherwise treat as a failure. Append
+      # --ignore-exit-code 8 so those non-matching projects don't fail the run. The trade-off
+      # (a mistyped filter that matches nothing anywhere would pass silently) is covered by the
+      # "at least one test ran" guard after the test run below.
       __TestFilterArg=
+      __TestFilterActive=0
       if [[ -n "$__TestFilter" ]]; then
-          __TestFilterArg="/p:TestRunnerAdditionalArguments=\"$__TestFilter\""
+          __TestFilterActive=1
+          __TestFilterArg="/p:TestRunnerAdditionalArguments=\"$__TestFilter --ignore-exit-code 8\""
       fi
 
       # When the managed build was skipped (e.g. the test-only CI legs that download prebuilt
@@ -377,6 +386,17 @@ if [[ "$__Test" == 1 ]]; then
           fi
       fi
 
+      # When a filter is active it is applied to every project in the traversal, so non-matching
+      # projects run zero tests. --ignore-exit-code 8 (added to __TestFilterArg above) keeps those
+      # from failing the run; to still catch a filter that matches nothing ANYWHERE, count the
+      # tests that ran after the build. Clear this run's result XMLs first so the post-run count
+      # only reflects the current run (result file names embed the target framework, so stale
+      # files from a previous run would not otherwise be overwritten).
+      __ResultsDir="$__RootBinDir/TestResults/$__BuildType"
+      if [[ "$__TestFilterActive" == 1 && -d "$__ResultsDir" ]]; then
+          rm -f "$__ResultsDir"/*.xml
+      fi
+
       # __CommonMSBuildArgs contains TargetOS property
       "$__RepoRootDir/eng/common/build.sh" \
         --test \
@@ -397,6 +417,23 @@ if [[ "$__Test" == 1 ]]; then
       if [ $? != 0 ]; then
           exit 1
       fi
+
+      # Guard against a filter that silently matches nothing (see note above): sum the test
+      # counts from the xUnit result XMLs this run produced and fail if nothing ran.
+      if [[ "$__TestFilterActive" == 1 ]]; then
+          __TestsRan=0
+          if [[ -d "$__ResultsDir" ]]; then
+              __TestsRan=$(cat "$__ResultsDir"/*.xml 2>/dev/null | grep -oE '<assembly [^>]*total="[0-9]+"' | grep -oE 'total="[0-9]+"' | grep -oE '[0-9]+' | awk '{s+=$1} END {print s+0}')
+          fi
+          if [[ -z "$__TestsRan" ]]; then
+              __TestsRan=0
+          fi
+          if [[ "$__TestsRan" == 0 ]]; then
+              echo "ERROR: The test filter matched zero tests across all projects. Check the -methodfilter/-classfilter value."
+              exit 1
+          fi
+          echo "Test filter matched $__TestsRan test(s) across the run."
+      fi
    fi
 fi
 

global.json

@@ -4,13 +4,11 @@
     "allowPrerelease": true,
     "rollForward": "major"
   },
+  "test": {
+    "runner": "Microsoft.Testing.Platform"
+  },
   "tools": {
-    "dotnet": "10.0.110",
-    "runtimes": {
-      "dotnet/x86": [
-        "$(MicrosoftNETCoreApp100Version)"
-      ]
-    }
+    "dotnet": "10.0.110"
   },
   "msbuild-sdks": {
     "Microsoft.Build.NoTargets": "3.7.0",

src/Microsoft.Diagnostics.TestHelpers/AcquireDotNetTestStep.cs

@@ -6,7 +6,7 @@
 using System.IO.Compression;
 using System.Net.Http;
 using System.Threading.Tasks;
-using Xunit.Abstractions;
+using Xunit;
 
 namespace Microsoft.Diagnostics.TestHelpers
 {

src/Microsoft.Diagnostics.TestHelpers/AssertX.cs

@@ -3,7 +3,7 @@
 
 using System;
 using System.IO;
-using Xunit.Abstractions;
+using Xunit;
 
 namespace Microsoft.Diagnostics.TestHelpers
 {

src/Microsoft.Diagnostics.TestHelpers/BaseDebuggeeCompiler.cs

@@ -5,7 +5,7 @@
 using System.Collections.Generic;
 using System.IO;
 using System.Threading.Tasks;
-using Xunit.Abstractions;
+using Xunit;
 
 namespace Microsoft.Diagnostics.TestHelpers
 {

src/Microsoft.Diagnostics.TestHelpers/ConsoleTestOutputHelper.cs

@@ -2,12 +2,26 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 
 using System;
-using Xunit.Abstractions;
+using Xunit;
 
 namespace Microsoft.Diagnostics.TestHelpers
 {
     public class ConsoleTestOutputHelper : ITestOutputHelper
     {
+        public string Output => string.Empty;
+
+        public void Write(string message)
+        {
+            Console.Write(message);
+            Console.Out.Flush();
+        }
+
+        public void Write(string format, params object[] args)
+        {
+            Console.Write(format, args);
+            Console.Out.Flush();
+        }
+
         public void WriteLine(string message)
         {
             Console.WriteLine(message);

src/Microsoft.Diagnostics.TestHelpers/CsprojBuildDebuggeeTestStep.cs

@@ -5,7 +5,7 @@
 using System.IO;
 using System.Threading.Tasks;
 using System.Xml.Linq;
-using Xunit.Abstractions;
+using Xunit;
 
 namespace Microsoft.Diagnostics.TestHelpers
 {

src/Microsoft.Diagnostics.TestHelpers/DebuggeeCompiler.cs

@@ -3,7 +3,7 @@
 
 using System;
 using System.Threading.Tasks;
-using Xunit.Abstractions;
+using Xunit;
 
 namespace Microsoft.Diagnostics.TestHelpers
 {

src/Microsoft.Diagnostics.TestHelpers/DotNetBuildDebuggeeTestStep.cs

@@ -7,7 +7,7 @@
 using System.Text;
 using System.Threading;
 using System.Threading.Tasks;
-using Xunit.Abstractions;
+using Xunit;
 
 namespace Microsoft.Diagnostics.TestHelpers
 {

src/Microsoft.Diagnostics.TestHelpers/FileTestOutputHelper.cs

@@ -3,7 +3,7 @@
 
 using System;
 using System.IO;
-using Xunit.Abstractions;
+using Xunit;
 
 namespace Microsoft.Diagnostics.TestHelpers
 {
@@ -24,6 +24,24 @@ public FileTestOutputHelper(string logFilePath, FileMode fileMode = FileMode.Cre
             _lock = new object();
         }
 
+        public string Output => string.Empty;
+
+        public void Write(string message)
+        {
+            lock (_lock)
+            {
+                _logWriter.Write(message);
+            }
+        }
+
+        public void Write(string format, params object[] args)
+        {
+            lock (_lock)
+            {
+                _logWriter.Write(format, args);
+            }
+        }
+
         public void WriteLine(string message)
         {
             lock (_lock)

src/Microsoft.Diagnostics.TestHelpers/IndentedTestOutputHelper.cs

@@ -1,7 +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 Xunit.Abstractions;
+using Xunit;
 
 namespace Microsoft.Diagnostics.TestHelpers
 {
@@ -20,6 +20,18 @@ public IndentedTestOutputHelper(ITestOutputHelper innerOutput, string indentText
             _indentText = indentText;
         }
 
+        public string Output => _output.Output;
+
+        public void Write(string message)
+        {
+            _output.Write(_indentText + message);
+        }
+
+        public void Write(string format, params object[] args)
+        {
+            _output.Write(_indentText + format, args);
+        }
+
         public void WriteLine(string message)
         {
             _output.WriteLine(_indentText + message);

src/Microsoft.Diagnostics.TestHelpers/LoggingListener.cs

@@ -4,7 +4,7 @@
 using System;
 using System.Diagnostics;
 using Microsoft.Diagnostics.DebugServices.Implementation;
-using Xunit.Abstractions;
+using Xunit;
 
 namespace Microsoft.Diagnostics.TestHelpers
 {

src/Microsoft.Diagnostics.TestHelpers/Microsoft.Diagnostics.TestHelpers.csproj

@@ -14,8 +14,8 @@
 
   <ItemGroup>
     <PackageReference Include="Microsoft.DotNet.RemoteExecutor" Version="$(MicrosoftDotNetRemoteExecutorVersion)" />
-    <PackageReference Include="xunit" Version="$(XUnitVersion)" />
-    <PackageReference Include="xunit.abstractions" Version="$(XUnitAbstractionsVersion)" />
+    <PackageReference Include="xunit.v3.extensibility.core" Version="$(XUnitV3Version)" />
+    <PackageReference Include="xunit.v3.assert" Version="$(XUnitV3Version)" />
   </ItemGroup>
 
   <ItemGroup>