Use DOTNET_STARTUP_HOOK to have the target run the tests (#91)

.github/workflows/dotnet.yaml

@@ -38,7 +38,7 @@ jobs:
     - name: Build
       run: 'nix develop --command dotnet build --no-restore --configuration ${{matrix.config}}'
     - name: Test
-      run: 'nix develop --command dotnet test --no-build --verbosity normal --configuration ${{matrix.config}}'
+      run: 'nix develop --command dotnet test --no-build --verbosity normal --configuration ${{matrix.config}} --framework net8.0'
 
   selftest:
     runs-on: ubuntu-latest
@@ -57,10 +57,6 @@ jobs:
       security-events: none
       statuses: read
 
-    strategy:
-      matrix:
-        framework: ["net6.0", "net8.0"]
-
     steps:
     - uses: actions/checkout@v4
       with:
@@ -75,7 +71,49 @@ jobs:
     - name: Build
       run: 'nix develop --command dotnet build --no-restore --configuration Release'
     - name: Test using self
-      run: 'nix develop --command dotnet exec ./WoofWare.NUnitTestRunner/bin/Release/net8.0/WoofWare.NUnitTestRunner.dll ./Consumer/bin/Release/${{matrix.framework}}/Consumer.dll --trx TrxOut/out.trx'
+      run: 'nix develop --command dotnet exec ./WoofWare.NUnitTestRunner/bin/Release/net6.0/WoofWare.NUnitTestRunner.dll ./Consumer/bin/Release/net8.0/Consumer.dll --trx TrxOut/out.trx'
+    - name: Parse Trx files
+      uses: NasAmin/trx-parser@v0.6.0
+      if: always()
+      id: trx-parser
+      with:
+        TRX_PATH: ${{ github.workspace }}/TrxOut
+        REPO_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+
+  selftest-net6:
+    runs-on: ubuntu-latest
+    permissions:
+      actions: none
+      checks: write
+      contents: read
+      deployments: none
+      id-token: none
+      issues: none
+      discussions: none
+      packages: none
+      pages: none
+      pull-requests: read
+      repository-projects: none
+      security-events: none
+      statuses: read
+
+    steps:
+    - uses: actions/checkout@v4
+      with:
+        fetch-depth: 0 # so that NerdBank.GitVersioning has access to history
+    - name: Install Nix
+      uses: cachix/install-nix-action@V27
+      with:
+        extra_nix_config: |
+          access-tokens = github.com=${{ secrets.GITHUB_TOKEN }}
+    - name: Restore dependencies
+      run: nix develop --command dotnet restore
+    - name: Build runner
+      run: 'nix develop --command dotnet build WoofWare.NUnitTestRunner --configuration Release'
+    - name: Build target
+      run: 'nix develop --command dotnet build Consumer --configuration Release'
+    - name: Test using self
+      run: 'nix develop .#net6 --command ./WoofWare.NUnitTestRunner/bin/Release/net6.0/WoofWare.NUnitTestRunner ./Consumer/bin/Release/net6.0/Consumer.dll --trx TrxOut/out.trx'
     - name: Parse Trx files
       uses: NasAmin/trx-parser@v0.6.0
       if: always()

Consumer/Consumer.fsproj

@@ -9,6 +9,7 @@
     <ItemGroup>
         <Compile Include="NoAttribute.fs" />
         <Compile Include="Inconclusive.fs" />
+        <Compile Include="RunSubProcess.fs" />
         <Compile Include="TestNonParallel.fs" />
         <Compile Include="TestParallel.fs" />
         <Compile Include="TestStdout.fs" />

Consumer/RunSubProcess.fs

@@ -0,0 +1,45 @@
+namespace Consumer
+
+open System
+open System.Diagnostics
+open System.IO
+open System.IO.Compression
+open System.Text
+open NUnit.Framework
+open FsUnitTyped
+
+[<TestFixture>]
+module RunSubProcess =
+    [<Test>]
+    let ``Run a subprocess`` () =
+        let exe = "/bin/bash"
+        let args = [ "-c" ; "echo hi >&2 && echo bye" ]
+        let workingDir = None
+
+        let psi =
+            ProcessStartInfo (
+                exe,
+                UseShellExecute = false,
+                RedirectStandardError = true,
+                RedirectStandardOutput = true,
+                WorkingDirectory = Option.toObj workingDir
+            )
+
+        for arg in args do
+            psi.ArgumentList.Add arg
+
+        psi.EnvironmentVariables.Add ("THING", Path.Combine (AppDomain.CurrentDomain.BaseDirectory, "hi"))
+        let stderr = StringBuilder ()
+        use proc = new Process (StartInfo = psi)
+        proc.OutputDataReceived.Add (fun e -> printfn $"%s{e.Data}")
+
+        proc.ErrorDataReceived.Add (fun e ->
+            eprintfn $"%s{e.Data}"
+            stderr.AppendLine e.Data |> ignore
+        )
+
+        proc.Start () |> shouldEqual true
+        proc.BeginOutputReadLine ()
+        proc.BeginErrorReadLine ()
+
+        proc.WaitForExit ()

WoofWare.NUnitTestRunner.Lib/AppContext.fs

@@ -1,34 +0,0 @@
-namespace WoofWare.NUnitTestRunner
-
-open System
-open System.IO
-open System.Reflection
-
-// Fix for https://github.com/Smaug123/unofficial-nunit-runner/issues/8
-// (This tells the DLL loader to look next to the test DLL for dependencies.)
-// TODO: do we actually need this when we move to the Hooks world?
-/// Context manager to set the AppContext.BaseDirectory of the executing DLL.
-type SetBaseDir (testDll : FileInfo) =
-    let oldBaseDir = AppContext.BaseDirectory
-
-    let setData =
-        let appContext = Type.GetType "System.AppContext"
-
-        if Object.ReferenceEquals (appContext, (null : obj)) then
-            ignore<string * string>
-        else
-
-        let setDataMethod =
-            appContext.GetMethod ("SetData", BindingFlags.Static ||| BindingFlags.Public)
-
-        if Object.ReferenceEquals (setDataMethod, (null : obj)) then
-            ignore<string * string>
-        else
-
-        fun (k, v) -> setDataMethod.Invoke ((null : obj), [| k ; v |]) |> unbox<unit>
-
-    do setData ("APP_CONTEXT_BASE_DIRECTORY", testDll.Directory.FullName)
-
-    interface IDisposable with
-        member _.Dispose () =
-            setData ("APP_CONTEXT_BASE_DIRECTORY", oldBaseDir)

WoofWare.NUnitTestRunner.Lib/Context.fs

@@ -89,8 +89,13 @@ type TestContexts =
             AsyncLocal = local
         }
 
-    member internal this.Stdout : TextWriter = this.StdOutWriter
-    member internal this.Stderr : TextWriter = this.StdErrWriter
+    /// An output stream which will identify the ExecutionContext it's being written to from,
+    /// and will separate that output into its own stream internally.
+    member this.Stdout : TextWriter = this.StdOutWriter
+
+    /// An output stream which will identify the ExecutionContext it's being written to from,
+    /// and will separate that output into its own stream internally.
+    member this.Stderr : TextWriter = this.StdErrWriter
 
     member internal this.DumpStdout (id : OutputStreamId) : string =
         lock

WoofWare.NUnitTestRunner.Lib/SurfaceBaseline.txt

@@ -243,8 +243,6 @@ WoofWare.NUnitTestRunner.ParallelQueue.Run [method]: WoofWare.NUnitTestRunner.Te
 WoofWare.NUnitTestRunner.ParallelQueue.RunTestSetup [method]: WoofWare.NUnitTestRunner.TestFixtureRunningToken -> (unit -> 'a) -> ('a * WoofWare.NUnitTestRunner.TestFixtureSetupToken) System.Threading.Tasks.Task
 WoofWare.NUnitTestRunner.ParallelQueue.RunTestTearDown [method]: WoofWare.NUnitTestRunner.TestFixtureSetupToken -> (unit -> 'a) -> ('a * WoofWare.NUnitTestRunner.TestFixtureTearDownToken) System.Threading.Tasks.Task
 WoofWare.NUnitTestRunner.ParallelQueue.StartTestFixture [method]: WoofWare.NUnitTestRunner.TestFixture -> WoofWare.NUnitTestRunner.TestFixtureRunningToken System.Threading.Tasks.Task
-WoofWare.NUnitTestRunner.SetBaseDir inherit obj, implements IDisposable
-WoofWare.NUnitTestRunner.SetBaseDir..ctor [constructor]: System.IO.FileInfo
 WoofWare.NUnitTestRunner.SingleTestMethod inherit obj, implements WoofWare.NUnitTestRunner.SingleTestMethod System.IEquatable, System.Collections.IStructuralEquatable
 WoofWare.NUnitTestRunner.SingleTestMethod..ctor [constructor]: (System.Reflection.MethodInfo, WoofWare.NUnitTestRunner.TestKind, WoofWare.NUnitTestRunner.Modifier list, string list, int option, WoofWare.NUnitTestRunner.Combinatorial option, unit WoofWare.NUnitTestRunner.Parallelizable option)
 WoofWare.NUnitTestRunner.SingleTestMethod.Categories [property]: [read-only] string list
@@ -267,6 +265,10 @@ WoofWare.NUnitTestRunner.SingleTestMethodModule inherit obj
 WoofWare.NUnitTestRunner.SingleTestMethodModule.parse [static method]: string list -> System.Reflection.MethodInfo -> System.Reflection.CustomAttributeData list -> (WoofWare.NUnitTestRunner.SingleTestMethod option * System.Reflection.CustomAttributeData list)
 WoofWare.NUnitTestRunner.TestContexts inherit obj, implements WoofWare.NUnitTestRunner.TestContexts System.IEquatable, System.Collections.IStructuralEquatable, IDisposable
 WoofWare.NUnitTestRunner.TestContexts.Empty [static method]: unit -> WoofWare.NUnitTestRunner.TestContexts
+WoofWare.NUnitTestRunner.TestContexts.get_Stderr [method]: unit -> System.IO.TextWriter
+WoofWare.NUnitTestRunner.TestContexts.get_Stdout [method]: unit -> System.IO.TextWriter
+WoofWare.NUnitTestRunner.TestContexts.Stderr [property]: [read-only] System.IO.TextWriter
+WoofWare.NUnitTestRunner.TestContexts.Stdout [property]: [read-only] System.IO.TextWriter
 WoofWare.NUnitTestRunner.TestFailure inherit obj, implements WoofWare.NUnitTestRunner.TestFailure System.IEquatable, System.Collections.IStructuralEquatable - union type with 3 cases
 WoofWare.NUnitTestRunner.TestFailure+SetUpFailed inherit WoofWare.NUnitTestRunner.TestFailure
 WoofWare.NUnitTestRunner.TestFailure+SetUpFailed.get_Item [method]: unit -> WoofWare.NUnitTestRunner.UserMethodFailure
@@ -397,6 +399,7 @@ WoofWare.NUnitTestRunner.TestMemberSuccess.Ok [static property]: [read-only] Woo
 WoofWare.NUnitTestRunner.TestMemberSuccess.Tag [property]: [read-only] int
 WoofWare.NUnitTestRunner.TestProgress inherit obj
 WoofWare.NUnitTestRunner.TestProgress.toStderr [static method]: unit -> WoofWare.NUnitTestRunner.ITestProgress
+WoofWare.NUnitTestRunner.TestProgress.toWriter [static method]: System.IO.TextWriter -> WoofWare.NUnitTestRunner.ITestProgress
 WoofWare.NUnitTestRunner.TrxCounters inherit obj, implements WoofWare.NUnitTestRunner.TrxCounters System.IEquatable, System.Collections.IStructuralEquatable
 WoofWare.NUnitTestRunner.TrxCounters..ctor [constructor]: (System.UInt32, System.UInt32, System.UInt32, System.UInt32, System.UInt32, System.UInt32, System.UInt32, System.UInt32, System.UInt32, System.UInt32, System.UInt32, System.UInt32, System.UInt32, System.UInt32, System.UInt32, System.UInt32)
 WoofWare.NUnitTestRunner.TrxCounters.Aborted [property]: [read-only] System.UInt32

WoofWare.NUnitTestRunner.Lib/TestProgress.fs

@@ -1,6 +1,7 @@
 namespace WoofWare.NUnitTestRunner
 
 open System
+open System.IO
 
 /// Represents something which knows how to report progress through a test suite.
 /// Note that we don't guarantee anything about parallelism; you must make sure
@@ -24,22 +25,25 @@ type ITestProgress =
 /// Methods for constructing specific ITestProgress objects.
 [<RequireQualifiedAccess>]
 module TestProgress =
-    /// An ITestProgress which logs to stderr.
-    let toStderr () : ITestProgress =
+    /// An ITestProgress which logs to the given writer.
+    let toWriter (writer : TextWriter) : ITestProgress =
         { new ITestProgress with
             member _.OnTestFixtureStart name testCount =
                 let plural = if testCount = 1 then "" else "s"
-                Console.Error.WriteLine $"Running test fixture: %s{name} (%i{testCount} test%s{plural} to run)"
+                writer.WriteLine $"Running test fixture: %s{name} (%i{testCount} test%s{plural} to run)"
 
             member _.OnTestMemberStart name =
-                Console.Error.WriteLine $"Running test: %s{name}"
+                writer.WriteLine $"Running test: %s{name}"
 
             member _.OnTestFailed name failure =
-                Console.Error.WriteLine $"Test failed: %O{failure}"
+                writer.WriteLine $"Test failed: %O{failure}"
 
             member _.OnTestMemberFinished name =
-                Console.Error.WriteLine $"Finished test %s{name}"
+                writer.WriteLine $"Finished test %s{name}"
 
             member _.OnTestMemberSkipped name =
-                Console.Error.WriteLine $"Skipping test due to filter: %s{name}"
+                writer.WriteLine $"Skipping test due to filter: %s{name}"
         }
+
+    /// An ITestProgress which logs to stderr.
+    let toStderr () : ITestProgress = toWriter Console.Error

WoofWare.NUnitTestRunner.Lib/WoofWare.NUnitTestRunner.Lib.fsproj

@@ -19,7 +19,6 @@
 
     <ItemGroup>
       <Compile Include="AssemblyInfo.fs" />
-      <Compile Include="AppContext.fs" />
       <Compile Include="RuntimeConfig.fs" />
       <Compile Include="GeneratedRuntimeConfig.fs">
         <MyriadFile>RuntimeConfig.fs</MyriadFile>

WoofWare.NUnitTestRunner.Lib/version.json

@@ -1,5 +1,5 @@
 {
-  "version": "0.15",
+  "version": "0.16",
   "publicReleaseRefSpec": [
     "^refs/heads/main$"
   ],

WoofWare.NUnitTestRunner.StartupHook/StartupHook.cs

@@ -0,0 +1,35 @@
+using System.Linq;
+using System.Reflection;
+using System.Runtime.Loader;
+using WoofWare.NUnitTestRunner.StartupHook;
+
+namespace WoofWare.NUnitTestRunner.StartupHook
+{
+    internal class StartupAssemblyLoadContext : AssemblyLoadContext
+    {
+        private readonly AssemblyDependencyResolver _resolver;
+
+        public StartupAssemblyLoadContext()
+        {
+            _resolver = new AssemblyDependencyResolver(Assembly.GetExecutingAssembly().Location);
+        }
+
+        protected override Assembly Load(AssemblyName assemblyName)
+        {
+            var assemblyPath = _resolver.ResolveAssemblyToPath(assemblyName);
+
+            return assemblyPath != null ? LoadFromAssemblyPath(assemblyPath) : null;
+        }
+    }
+}
+
+// Must be internal and called `StartupHook`
+internal class StartupHook
+{
+    public static void Initialize()
+    {
+        var loadContext = new StartupAssemblyLoadContext();
+        var assembly = loadContext.LoadFromAssemblyName(new AssemblyName("WoofWare.NUnitTestRunner.StartupHookLogic"));
+        assembly.DefinedTypes.First(x => x.Name == "StartupHookLogic").GetDeclaredMethod("DoIt")!.Invoke(null, null);
+    }
+}

WoofWare.NUnitTestRunner.StartupHook/WoofWare.NUnitTestRunner.StartupHook.csproj

@@ -0,0 +1,17 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFramework>net6.0</TargetFramework>
+    <EnableDefaultCompileItems>false</EnableDefaultCompileItems>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\WoofWare.NUnitTestRunner.StartupHookLogic\WoofWare.NUnitTestRunner.StartupHookLogic.csproj" />
+    <ProjectReference Include="..\WoofWare.NUnitTestRunner.Lib\WoofWare.NUnitTestRunner.Lib.fsproj"/>
+  </ItemGroup>
+
+  <ItemGroup>
+    <Compile Include="StartupHook.cs"/>
+  </ItemGroup>
+
+</Project>

WoofWare.NUnitTestRunner.StartupHookLogic/StartupHookLogic.cs

@@ -0,0 +1,102 @@
+using System.Reflection;
+using Microsoft.FSharp.Collections;
+using Microsoft.FSharp.Core;
+
+namespace WoofWare.NUnitTestRunner.StartupHookLogic;
+
+public class StartupHookLogic
+{
+    private static void DoIt()
+    {
+        // Load test runner lib
+        var nunitLib = Environment.GetEnvironmentVariable("WOOFWARE_NUNIT_LIB");
+        if (string.IsNullOrEmpty(nunitLib))
+        {
+            throw new ArgumentException("WoofWare.NUnitTestRunner hook expects to run with WOOFWARE_NUNIT_LIB set to WoofWare.NUnitTestRunner.Lib.dll");
+        }
+        Assembly.LoadFrom(nunitLib);
+
+        var startTime = DateTimeOffset.Now;
+
+        // Arg parsing
+
+        var filterVar = Environment.GetEnvironmentVariable("WOOFWARE_NUNIT_FILTER");
+        static bool NoFilter(TestFixture f, SingleTestMethod g)
+        {
+            return true;
+        }
+
+        FSharpFunc<TestFixture, FSharpFunc<SingleTestMethod, bool>> filter;
+        if (string.IsNullOrEmpty(filterVar))
+        {
+            filter = FuncConvert.FromFunc<TestFixture, SingleTestMethod, bool>(NoFilter);
+        }
+        else
+        {
+            filter = FilterModule.shouldRun(FilterModule.parse(filterVar));
+        }
+
+        var assy = Assembly.GetEntryAssembly()!;
+
+        var attrs = AssemblyLevelAttributesModule.get(assy);
+
+        FSharpOption<int> levelOfParallelism;
+        var parallelismVar = Environment.GetEnvironmentVariable("WOOFWARE_NUNIT_PARALLELISM_LEVEL");
+        if (string.IsNullOrEmpty(parallelismVar))
+        {
+            levelOfParallelism = attrs.Parallelism;
+        }
+        else
+        {
+            levelOfParallelism = FSharpOption<int>.Some(Int32.Parse(parallelismVar));
+        }
+
+        var testFixtures = assy.ExportedTypes.Select(TestFixtureModule.parse);
+        using var par =
+            new ParallelQueue(levelOfParallelism, attrs.Parallelizable, FSharpOption<CancellationToken>.None);
+        var creationTime = DateTimeOffset.Now;
+
+        var timeoutVar = Environment.GetEnvironmentVariable("WOOFWARE_NUNIT_TIMEOUT_SECS");
+        TimeSpan timeout;
+        if (string.IsNullOrEmpty(timeoutVar))
+        {
+            timeout = TimeSpan.FromHours(2.0);
+        }
+        else
+        {
+            timeout = TimeSpan.FromSeconds(Int32.Parse(timeoutVar));
+        }
+
+        var normalErr = Console.Error;
+        using var contexts = TestContexts.Empty();
+        Console.SetOut(contexts.Stdout);
+        Console.SetError(contexts.Stderr);
+        var results =
+            Task.WhenAll(testFixtures.Select(x =>
+                TestFixtureModule.run(contexts, par, TestProgress.toWriter(normalErr), filter, x)));
+
+        if (!results.Wait(timeout))
+        {
+            throw new Exception($"Tests failed to terminate within timeout of {timeout}");
+        }
+
+        var sorted =
+            results.Result.SelectMany(x => x);
+        var report = BuildTrxReport.build(assy, creationTime, startTime, ListModule.OfSeq(sorted));
+
+        var trxFile = Environment.GetEnvironmentVariable("WOOFWARE_NUNIT_GENERATE_TRX");
+        if (!string.IsNullOrEmpty(trxFile))
+        {
+            var contents = TrxReportModule.toXml(report).OuterXml;
+            var trxPath = new FileInfo(trxFile);
+            trxPath.Directory!.Create();
+            File.WriteAllText(trxPath.FullName, contents);
+            normalErr.WriteLine($"Written TRX file: {trxPath.FullName}");
+        }
+
+        if (report.ResultsSummary.Outcome.Equals(TrxOutcome.Completed))
+            Environment.Exit(0);
+        else
+            Environment.Exit(1);
+    }
+}

WoofWare.NUnitTestRunner.StartupHookLogic/WoofWare.NUnitTestRunner.StartupHookLogic.csproj

@@ -0,0 +1,18 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFramework>net6.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+    <EnableDefaultCompileItems>false</EnableDefaultCompileItems>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\WoofWare.NUnitTestRunner.Lib\WoofWare.NUnitTestRunner.Lib.fsproj"/>
+  </ItemGroup>
+
+  <ItemGroup>
+    <Compile Include="StartupHookLogic.cs"/>
+  </ItemGroup>
+
+</Project>

WoofWare.NUnitTestRunner.sln

@@ -8,6 +8,10 @@ Project("{F2A71F9B-5D33-465A-A702-920D77279786}") = "WoofWare.NUnitTestRunner.Li
 EndProject
 Project("{F2A71F9B-5D33-465A-A702-920D77279786}") = "WoofWare.NUnitTestRunner.Test", "WoofWare.NUnitTestRunner\WoofWare.NUnitTestRunner.Test\WoofWare.NUnitTestRunner.Test.fsproj", "{443B01B3-2A8C-45CF-96D6-1D890EEA0533}"
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "WoofWare.NUnitTestRunner.StartupHook", "WoofWare.NUnitTestRunner.StartupHook\WoofWare.NUnitTestRunner.StartupHook.csproj", "{E2C73D96-570C-4E3C-B997-707AF8BB0E6A}"
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "WoofWare.NUnitTestRunner.StartupHookLogic", "WoofWare.NUnitTestRunner.StartupHookLogic\WoofWare.NUnitTestRunner.StartupHookLogic.csproj", "{A70627C8-9D19-42C2-AFEB-CFBDDDCE045D}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -30,5 +34,13 @@ Global
 		{443B01B3-2A8C-45CF-96D6-1D890EEA0533}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{443B01B3-2A8C-45CF-96D6-1D890EEA0533}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{443B01B3-2A8C-45CF-96D6-1D890EEA0533}.Release|Any CPU.Build.0 = Release|Any CPU
+		{E2C73D96-570C-4E3C-B997-707AF8BB0E6A}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{E2C73D96-570C-4E3C-B997-707AF8BB0E6A}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{E2C73D96-570C-4E3C-B997-707AF8BB0E6A}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{E2C73D96-570C-4E3C-B997-707AF8BB0E6A}.Release|Any CPU.Build.0 = Release|Any CPU
+		{A70627C8-9D19-42C2-AFEB-CFBDDDCE045D}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{A70627C8-9D19-42C2-AFEB-CFBDDDCE045D}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{A70627C8-9D19-42C2-AFEB-CFBDDDCE045D}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{A70627C8-9D19-42C2-AFEB-CFBDDDCE045D}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 EndGlobal

WoofWare.NUnitTestRunner/Program.fs

@@ -1,12 +1,15 @@
 namespace WoofWare.NUnitTestRunner
 
 open System
+open System.Diagnostics
 open System.IO
+open System.Reflection
 open System.Threading.Tasks
 open Spectre.Console
 
 module Program =
-    let main argv =
+    // This is actually transcribed into C# in WoofWare.NUnitTestRunner.StartupHookLogic.
+    let execute argv =
         let startTime = DateTimeOffset.Now
 
         let args = argv |> List.ofArray |> Args.Parse
@@ -31,8 +34,6 @@ module Program =
             for d in runtime do
                 stderr.WriteLine $".NET runtime directory: %s{d.FullName}"
 
-        use _ = new SetBaseDir (args.Dll)
-
         use contexts = TestContexts.Empty ()
 
         let ctx = LoadContext (args.Dll, runtime, contexts)
@@ -89,6 +90,52 @@ module Program =
         | TrxOutcome.Completed -> 0
         | _ -> 1
 
+    let main argv =
+        let args = argv |> List.ofArray |> Args.Parse
+
+        let psi = ProcessStartInfo "dotnet"
+
+        match args.Trx with
+        | None -> ()
+        | Some trx -> psi.EnvironmentVariables.Add ("WOOFWARE_NUNIT_GENERATE_TRX", trx.FullName)
+
+        match args.LevelOfParallelism with
+        | None -> ()
+        | Some par -> psi.EnvironmentVariables.Add ("WOOFWARE_NUNIT_PARALLELISM_LEVEL", string<int> par)
+
+        match args.Filter with
+        | None -> ()
+        | Some (filter, _) -> psi.EnvironmentVariables.Add ("WOOFWARE_NUNIT_FILTER", filter)
+
+        match args.Timeout with
+        | None -> ()
+        | Some timeout ->
+            psi.EnvironmentVariables.Add ("WOOFWARE_NUNIT_TIMEOUT_SECS", string<int> (int<float> timeout.TotalSeconds))
+
+        psi.ArgumentList.Add "exec"
+        psi.ArgumentList.Add args.Dll.FullName
+
+        let us = Assembly.GetExecutingAssembly().Location |> FileInfo
+
+        let startupHook =
+            Path.Combine (us.Directory.FullName, "WoofWare.NUnitTestRunner.StartupHook.dll")
+
+        psi.EnvironmentVariables.Add ("DOTNET_STARTUP_HOOKS", startupHook)
+
+        psi.EnvironmentVariables.Add (
+            "WOOFWARE_NUNIT_LIB",
+            Path.Combine (us.Directory.FullName, "WoofWare.NUnitTestRunner.Lib.dll")
+        )
+
+        use proc = new Process ()
+        proc.StartInfo <- psi
+
+        if not (proc.Start ()) then
+            failwith "Failed to start dotnet"
+
+        proc.WaitForExit ()
+        proc.ExitCode
+
     [<EntryPoint>]
     let reallyMain argv =
         // Hack to make sure `finally`s get run.

WoofWare.NUnitTestRunner/WoofWare.NUnitTestRunner.fsproj

@@ -2,7 +2,8 @@
 
   <PropertyGroup>
     <OutputType>Exe</OutputType>
-    <TargetFramework>net8.0</TargetFramework>
+    <TargetFramework>net6.0</TargetFramework>
+    <RollForward>Major</RollForward>
     <PackAsTool>true</PackAsTool>
     <GenerateDocumentationFile>true</GenerateDocumentationFile>
     <Authors>Patrick Stevens</Authors>
@@ -29,6 +30,8 @@
 
   <ItemGroup>
     <ProjectReference Include="..\WoofWare.NUnitTestRunner.Lib\WoofWare.NUnitTestRunner.Lib.fsproj" />
+    <ProjectReference Include="..\WoofWare.NUnitTestRunner.StartupHookLogic\WoofWare.NUnitTestRunner.StartupHookLogic.csproj" />
+    <ProjectReference Include="..\WoofWare.NUnitTestRunner.StartupHook\WoofWare.NUnitTestRunner.StartupHook.csproj" />
   </ItemGroup>
 
   <ItemGroup>

flake.nix

@@ -56,13 +56,20 @@
           doCheck = true;
         };
       };
-      devShell = pkgs.mkShell {
-        packages = [
-          (pkgs.dotnetCorePackages.combinePackages [dotnet-sdk pkgs.dotnetCorePackages.runtime_6_0])
-          pkgs.alejandra
-          pkgs.nodePackages.markdown-link-check
-          pkgs.shellcheck
-        ];
+      devShells = {
+        default = pkgs.mkShell {
+          packages = [
+            dotnet-sdk
+            pkgs.alejandra
+            pkgs.nodePackages.markdown-link-check
+            pkgs.shellcheck
+          ];
+        };
+        net6 = pkgs.mkShell {
+          packages = [
+            pkgs.dotnetCorePackages.runtime_6_0
+          ];
+        };
       };
     });
 }