mstest 3.4.1 does not discover a method from unit tests in visual studio when returning a Task with multiple frameworks

[Frederic Forjan]

Describe the bug

mstest 3.4.1 does not discover a method from unit tests in visual when returning a Task with multiple frameworks

[Warning] [MSTest][Discovery][C:\Users\ISYS36005\source\repos\TestProject1\bin\Debug\net6.0-windows\TestProject1.dll] MSTestAdapter failed to discover tests in class 'TestProject1.UnitTest1' of assembly 'source\repos\TestProject1\bin\Debug\net6.0-windows\TestProject1.dll' because Method 'get_DataRow' in type 'Microsoft.VisualStudio.TestPlatform.MSTestAdapter.PlatformServices.TestContextImplementation' from assembly 'Microsoft.VisualStudio.TestPlatform.MSTestAdapter.PlatformServices, Version=14.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a' does not have an implementation..

Steps To Reproduce

Create a new unit tests project in a new solution with a method returning a task :

notice that the frameworks targets both net472 and net6.0-windows

Expected behavior

Both tests in both framework should be discovered and be able to execute

Actual behavior

net6.0-windows is not discovered

Additional context

Tested in Visual Studio 2022 17.10.0

[Amaury Levé]

Cannot repro the issue in VS nor CLI using vstest.console.exe or dotnet test

Repro project:

<Project Sdk="Microsoft.NET.Sdk">

  <PropertyGroup>
    <TargetFrameworks>net472;net6.0-windows</TargetFrameworks>
    <ImplicitUsings>enable</ImplicitUsings>
    <Nullable>enable</Nullable>
    <LangVersion>12</LangVersion>
    <IsPackable>false</IsPackable>
    <IsTestProject>true</IsTestProject>
  </PropertyGroup>

  <ItemGroup>
    <PackageReference Include="MSTest" Version="3.4.1" />
    <PackageReference Include="coverlet.collector" Version="6.0.0" />
  </ItemGroup>
  
  <ItemGroup>
	<Using Include="Microsoft.VisualStudio.TestTools.UnitTesting" />
  </ItemGroup>

</Project>

test class

namespace TestProject2
{
    [TestClass]
    public class UnitTest1
    {
        [TestMethod]
        public Task TestMethod2()
        {
            return Task.CompletedTask;
        }
    }
}

[Frederic Forjan]

ok, recipe update.

• you have everything working.
  add the [DeploymentItem("Foo")] on the test itself
• build, run the test
  the test cannot be discovered in net6 - that's issue #3019
• remove the [DeploymentItem] attribute & build
• the test disappears

[Frederic Forjan]

and from that stage onwards, if the test method is back to a void, it is discovered, if it move back to a Task, it cannot be discovered !

[Amaury Levé]

Fixed by #3034