NUnit

Run NUnit 5.0.0 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. NUnit is the default engine. TUnit and MSTest are opt-in: TUnit, MSTest.

Project setup

Add the adapter and NUnit to the test project:

<PropertyGroup>
  <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="NUnit" Version="5.0.0" />
  <PackageReference Include="Revit_All_Main_Versions_API_x64" Version="2025.0.*"
    IncludeAssets="build; compile" PrivateAssets="All" />
</ItemGroup>

Create global.json beside the test .csproj so this project uses Microsoft Testing Platform:

{
  "sdk": { "version": "10.0.0", "rollForward": "latestMinor" },
  "test": { "runner": "Microsoft.Testing.Platform" }
}

The adapter is MTP-native. 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. The package flattens testhost output so a leftover RID does not nest under win-x64.

The host properties in the project file select the Autodesk application. HostName is Revit, AutoCad, Civil3D, Plant3D, AcadArch, AcadMech, AcadElec, AcadMep, or AcadMap3D. The host year must match the API references used to compile the test assembly.

Writing tests

Use normal NUnit attributes such as [TestFixture], [Test], [SetUp], and parameterized test cases. Tests execute in host context, so document access, transactions, selection, and UI-thread rules still apply.

[TestFixture]
public sealed class WallTests
{
    [Test]
    public void Active_document_is_available()
    {
        Assert.That(Context.Document, Is.Not.Null);
    }
}

Running

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

Run the command from the test project directory, where global.json and the .csproj live. Use the adapter's --filter option with a method-name substring; use --list-tests to inspect discovered tests. Set <ForceLaunch>true</ForceLaunch> in the project when a fresh host is required.

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 MTP packages and NUnit references are present; do not use VSTest adapters
Host does not start	Check hostName, hostVersion, installation path, and launchTimeout
Test times out	Check modal dialogs, document state, and perTestTimeout
API call fails	Verify the test is executing inside the expected host and target framework

See Testing Overview for the shared pipe and lifecycle model.