Support ValueTask-returning test methods for all target frameworks (#4059)

Directory.Packages.props

@@ -19,6 +19,7 @@
     <!-- CVE-2017-0247 -->
     <SystemNetWebSocketsClientVersion>4.3.1</SystemNetWebSocketsClientVersion>
     <SystemTextRegularExpressionsVersion>4.3.1</SystemTextRegularExpressionsVersion>
+    <SystemThreadingTasksExtensionsVersion>4.5.4</SystemThreadingTasksExtensionsVersion>
   </PropertyGroup>
   <PropertyGroup Label="Test dependencies">
     <MicrosoftCodeAnalysisAnalyzerTestingVersion>1.1.3-beta1.24423.1</MicrosoftCodeAnalysisAnalyzerTestingVersion>
@@ -45,6 +46,7 @@
     <PackageVersion Include="Microsoft.TestPlatform.TranslationLayer" Version="$(MicrosoftNETTestSdkVersion)" />
     <PackageVersion Include="Microsoft.WindowsAppSDK" Version="1.0.0" />
     <PackageVersion Include="Polyfill" Version="7.4.0" />
+    <PackageVersion Include="System.Threading.Tasks.Extensions" Version="$(SystemThreadingTasksExtensionsVersion)" />
     <!-- CVE-2019-0820 -->
     <PackageVersion Include="System.Diagnostics.TextWriterTraceListener" Version="4.3.0" />
     <!-- CVE-2019-0981, CVE-2019-0980, CVE-2019-0657 -->

src/Adapter/MSTest.TestAdapter/Extensions/MethodInfoExtensions.cs

@@ -103,9 +103,7 @@ internal static class MethodInfoExtensions
     /// <returns>True if the method has a void/task return type..</returns>
     internal static bool IsValidReturnType(this MethodInfo method)
         => ReflectHelper.MatchReturnType(method, typeof(Task))
-#if NETCOREAPP
         || ReflectHelper.MatchReturnType(method, typeof(ValueTask))
-#endif
         || (ReflectHelper.MatchReturnType(method, typeof(void)) && method.GetAsyncTypeName() == null);
 
     /// <summary>
@@ -201,11 +199,9 @@ internal static class MethodInfoExtensions
         {
             task.GetAwaiter().GetResult();
         }
-#if NET6_0_OR_GREATER
         else if (invokeResult is ValueTask valueTask)
         {
             valueTask.GetAwaiter().GetResult();
         }
-#endif
     }
 }

src/Adapter/MSTest.TestAdapter/MSTest.TestAdapter.Linux.nuspec

@@ -6,6 +6,7 @@
       <group targetFramework="netstandard2.0">
         <dependency id="Microsoft.Testing.Extensions.VSTestBridge" version="$TestingPlatformVersion$" />
         <dependency id="Microsoft.Testing.Platform.MSBuild" version="$TestingPlatformVersion$" />
+        <dependency id="System.Threading.Tasks.Extensions" version="$SystemThreadingTasksExtensionsVersion$" />
       </group>
       <group targetFramework="netcoreapp3.1">
         <dependency id="Microsoft.Testing.Extensions.VSTestBridge" version="$TestingPlatformVersion$" />

src/Adapter/MSTest.TestAdapter/MSTest.TestAdapter.csproj

@@ -53,6 +53,7 @@
 
   <ItemGroup>
     <PackageReference Include="Microsoft.TestPlatform.AdapterUtilities" />
+    <PackageReference Include="System.Threading.Tasks.Extensions" Condition="'$(TargetFramework)'=='netstandard2.0' OR '$(TargetFramework)' == '$(NetFrameworkMinimum)' OR '$(TargetFramework)'=='$(UwpMinimum)'" />
   </ItemGroup>
 
   <ItemGroup>
@@ -80,6 +81,7 @@
     <NuspecProperty Include="ArtifactsBinDir=$(ArtifactsBinDir)" />
     <NuspecProperty Include="Configuration=$(Configuration)" />
     <NuspecProperty Include="TestingPlatformVersion=$(Version.Replace('$(VersionPrefix)', '$(TestingPlatformVersionPrefix)'))" />
+    <NuspecProperty Include="SystemThreadingTasksExtensionsVersion=$(SystemThreadingTasksExtensionsVersion)" />
   </ItemGroup>
 
   <ItemGroup>

src/Adapter/MSTest.TestAdapter/MSTest.TestAdapter.nuspec

@@ -6,12 +6,16 @@
       <group targetFramework="netstandard2.0">
         <dependency id="Microsoft.Testing.Extensions.VSTestBridge" version="$TestingPlatformVersion$" />
         <dependency id="Microsoft.Testing.Platform.MSBuild" version="$TestingPlatformVersion$" />
+        <dependency id="System.Threading.Tasks.Extensions" version="$SystemThreadingTasksExtensionsVersion$" />
       </group>
       <group targetFramework="net462">
         <dependency id="Microsoft.Testing.Extensions.VSTestBridge" version="$TestingPlatformVersion$" />
         <dependency id="Microsoft.Testing.Platform.MSBuild" version="$TestingPlatformVersion$" />
+        <dependency id="System.Threading.Tasks.Extensions" version="$SystemThreadingTasksExtensionsVersion$" />
+      </group>
+      <group targetFramework="uap10.0">
+        <dependency id="System.Threading.Tasks.Extensions" version="$SystemThreadingTasksExtensionsVersion$" />
       </group>
-      <group targetFramework="uap10.0" />
       <group targetFramework="netcoreapp3.1">
         <dependency id="Microsoft.Testing.Extensions.VSTestBridge" version="$TestingPlatformVersion$" />
         <dependency id="Microsoft.Testing.Platform.MSBuild" version="$TestingPlatformVersion$" />

test/IntegrationTests/MSTest.Acceptance.IntegrationTests/ValueTaskTests.cs

@@ -14,9 +14,10 @@ public sealed class ValueTaskTests : AcceptanceTestBase
     public ValueTaskTests(ITestExecutionContext testExecutionContext, TestAssetFixture testAssetFixture)
         : base(testExecutionContext) => _testAssetFixture = testAssetFixture;
 
-    public async Task CanUseValueTaskForAllKnownLocations()
+    [ArgumentsProvider(nameof(TargetFrameworks.All), typeof(TargetFrameworks))]
+    public async Task CanUseValueTaskForAllKnownLocations(string tfm)
     {
-        var testHost = TestHost.LocateFrom(_testAssetFixture.ProjectPath, TestAssetFixture.ProjectName, TargetFrameworks.NetCurrent.Arguments);
+        var testHost = TestHost.LocateFrom(_testAssetFixture.ProjectPath, TestAssetFixture.ProjectName, tfm);
         TestHostResult testHostResult = await testHost.ExecuteAsync();
 
         // Assert
@@ -35,7 +36,7 @@ public sealed class ValueTaskTests : AcceptanceTestBase
         {
             yield return (ProjectName, ProjectName,
                 SourceCode
-                .PatchTargetFrameworks(TargetFrameworks.NetCurrent)
+                .PatchTargetFrameworks(TargetFrameworks.All)
                 .PatchCodeWithReplace("$MSTestVersion$", MSTestVersion));
         }
 
@@ -63,41 +64,49 @@ using Microsoft.VisualStudio.TestTools.UnitTesting;
 [TestClass]
 public class UnitTest1
 {
+    private static ValueTask CompletedTask =>
+#if !NET5_0_OR_GREATER
+        // ValueTask.CompletedTask is only available in .NET 5 and later
+        default;
+#else
+        ValueTask.CompletedTask;
+#endif
+
     [AssemblyInitialize]
-    public static ValueTask AssemblyInitialize(TestContext testContext) => ValueTask.CompletedTask;
+    public static ValueTask AssemblyInitialize(TestContext testContext) => CompletedTask;
 
     [AssemblyCleanup]
-    public static ValueTask AssemblyCleanup() => ValueTask.CompletedTask;
+    public static ValueTask AssemblyCleanup() => CompletedTask;
 
     [ClassInitialize]
-    public static ValueTask ClassInitialize(TestContext testContext) => ValueTask.CompletedTask;
+    public static ValueTask ClassInitialize(TestContext testContext) => CompletedTask;
 
     [ClassCleanup]
-    public static ValueTask ClassCleanup() => ValueTask.CompletedTask;
+    public static ValueTask ClassCleanup() => CompletedTask;
 
     [TestInitialize]
-    public ValueTask TestInit() => ValueTask.CompletedTask;
+    public ValueTask TestInit() => CompletedTask;
 
     [TestCleanup]
-    public ValueTask TestCleanup() => ValueTask.CompletedTask;
+    public ValueTask TestCleanup() => CompletedTask;
 
     [TestMethod]
-    public async ValueTask TestMethod1() => await ValueTask.CompletedTask;
+    public async ValueTask TestMethod1() => await CompletedTask;
 
     [TestMethod]
-    public ValueTask TestMethod2() => ValueTask.CompletedTask;
+    public ValueTask TestMethod2() => CompletedTask;
 
     [TestMethod]
     public async ValueTask FailedTestMethod()
     {
-        await ValueTask.CompletedTask;
+        await CompletedTask;
         Assert.Fail();
     }
 
     [TestMethod]
     public async ValueTask InconclusiveTestMethod()
     {
-        await ValueTask.CompletedTask;
+        await CompletedTask;
         Assert.Inconclusive();
     }
 }