MSTest

Run MSTest 4.4.1 tests inside a live Revit or AutoCAD-family host through Microsoft Testing Platform (MTP) and the DevTools.TestAdapter assembly. The adapter is the public NuGet package RevitDevTool.TestAdapter 0.1.2. The host lifecycle is the same as for NUnit; the project SDK and attributes differ.

Project setup

Use Sdk="MSTest.Sdk" so EnableMSTestRunner is on. Microsoft.NET.Sdk with <EnableMSTestRunner>true</EnableMSTestRunner> is the other accepted shape. Without that runner, MSTest turns Microsoft.Testing.Platform off and no testhost entry point is generated.

<Project Sdk="MSTest.Sdk/4.4.1">
  <PropertyGroup>
    <TestingFramework>mstest</TestingFramework>
    <HostName>Revit</HostName>
    <HostVersion>2025</HostVersion>
    <ForceLaunch>false</ForceLaunch>
    <PerTestTimeout>60</PerTestTimeout>
    <LaunchTimeout>360</LaunchTimeout>
  </PropertyGroup>

  <ItemGroup>
    <PackageReference Include="RevitDevTool.TestAdapter" Version="0.1.2" />
    <PackageReference Include="Revit_All_Main_Versions_API_x64" Version="2025.0.*"
      IncludeAssets="build; compile" PrivateAssets="All" />
  </ItemGroup>
</Project>

Pin MSTest.Sdk 4.4.1 on the Sdk attribute, or in global.json:

{
  "sdk": { "version": "10.0.0", "rollForward": "latestMinor" },
  "test": { "runner": "Microsoft.Testing.Platform" },
  "msbuild-sdks": { "MSTest.Sdk": "4.4.1" }
}

The in-host closure is MSTest.TestFramework 4.4.1 plus Microsoft.Testing.Platform 2.4.1. A different MSTest version fails generation. Do not add NUnit3TestAdapter, Microsoft.Testing.Extensions.VSTestBridge, or a .runsettings file.

Do not set <RuntimeIdentifier> on net8 / net10. On net48, set win-x64 only when the SDK requires it for an x64 executable. HostName is Revit, AutoCad, Civil3D, Plant3D, AcadArch, AcadMech, AcadElec, AcadMep, or AcadMap3D.

Writing tests

Use normal MSTest attributes ([TestClass], [TestMethod], [TestInitialize]). Tests execute in host context, so document access, transactions, and UI-thread rules still apply.

Selecting one test also runs its [DependsOn] prerequisites (method and class, transitive).

[TestClass]
public sealed class WallTests
{
    [TestMethod]
    public void Active_document_is_available()
    {
        Assert.IsNotNull(Context.Document);
    }
}

Running

dotnet test --project .\MyHostTests.csproj -c Debug --filter Active_document

Run the command from a directory covered by the MTP global.json. --filter is a method name or substring. Use --list-tests to inspect discovered tests. The package shows standard output for passing tests (--output Detailed, --show-stdout All).

Debugging and troubleshooting

Attach Visual Studio, Rider, or C# Dev Kit to the Autodesk host process before running a test when you need to debug host API code. See Attach Debugger.

Symptom	Check
Zero tests discovered	Confirm TestingFramework is mstest, the project is MSTest.Sdk (or EnableMSTestRunner is true), and MTP is the dotnet test runner
Host does not start	Check HostName, HostVersion, installation path, and LaunchTimeout
Test times out	Check modal dialogs, document state, and PerTestTimeout
ChainStep stays 0 on a single test	The installed host is older than the adapter that closes [DependsOn]; redeploy RevitDevTool and restart the host

See Testing Overview for the shared pipe and lifecycle model.