Enable MS Testing Platform

This gets all tests running again. It also changes how test logs are collected to match changes from enabling the testing platform.

However, discovery fails for some tests due to the need to execute code to load MSBuild from the SDK first, and the new xunit v3 discovery system apparently reflects before instantiating test classes, leading to these failures.

CONTRIBUTING.md

@@ -43,7 +43,12 @@ NPM packages too.
 
 ## Testing
 
-The Visual Studio 2019 Test Explorer will list and execute all tests.
+`dotnet test` will run all tests.
+
+The Visual Studio 2022 Test Explorer will list and execute all tests.
+Visual Studio needs a preview feature called "Use testing platform server mode" enabled.
+
+A few tests will fail without a certain VC++ toolset installed.
 
 ## Releases
 

test/Cake.GitVersioning.Tests/Cake.GitVersioning.Tests.csproj

@@ -3,6 +3,7 @@
   <PropertyGroup>
     <TargetFrameworks>net8.0</TargetFrameworks>
     <OutputType>Exe</OutputType>
+    <TestingPlatformDotnetTestSupport>true</TestingPlatformDotnetTestSupport>
     <SignAssembly>false</SignAssembly>
     <IsTestProject>true</IsTestProject>
     <IsPackable>false</IsPackable>

test/Nerdbank.GitVersioning.Tests/Nerdbank.GitVersioning.Tests.csproj

@@ -3,6 +3,7 @@
     <TargetFrameworks>net9.0</TargetFrameworks>
     <TargetFrameworks Condition="$([MSBuild]::IsOSPlatform('Windows'))">$(TargetFrameworks);net472</TargetFrameworks>
     <OutputType>Exe</OutputType>
+    <TestingPlatformDotnetTestSupport>true</TestingPlatformDotnetTestSupport>
     <AutoGenerateBindingRedirects>true</AutoGenerateBindingRedirects>
     <GenerateBindingRedirectsOutputType>true</GenerateBindingRedirectsOutputType>
     <DebugType>full</DebugType>

tools/dotnet-test-cloud.ps1

@@ -44,8 +44,8 @@ if ($x86) {
   }
 }
 
-$testBinLog = Join-Path $ArtifactStagingFolder (Join-Path build_logs test.binlog)
-$testDiagLog = Join-Path $ArtifactStagingFolder (Join-Path test_logs diag.log)
+$testBinLog = Join-Path $ArtifactStagingFolder build_logs test.binlog
+$testResultsDirectory = Join-Path $ArtifactStagingFolder test_logs
 
 & $dotnet test $RepoRoot `
     --no-build `
@@ -56,8 +56,10 @@ $testDiagLog = Join-Path $ArtifactStagingFolder (Join-Path test_logs diag.log)
     --blame-hang-timeout 60s `
     --blame-crash `
     -bl:"$testBinLog" `
-    --diag "$testDiagLog;TraceLevel=info" `
-    --logger trx `
+    -- `
+    --results-directory $testResultsDirectory `
+    --report-xunit-trx `
+    --long-running 60 `
 
 $unknownCounter = 0
 Get-ChildItem -Recurse -Path $RepoRoot\test\*.trx |% {