VSTest -> Microsoft.Testing.Platform Migration

Migrate a .NET test solution from VSTest to Microsoft.Testing.Platform (MTP). The outcome is a solution where all test projects run on MTP, dotnet test works correctly, and CI/CD pipelines are updated.

First Action

Inspect the supplied project, Directory.Build.props, global.json, and CI files before searching the web or answering from memory. Resolve the framework and SDK mode first: .NET 9 and earlier use the compatibility property plus the -- separator; .NET 10 native MTP uses global.json, removes that property, and passes MTP arguments without the separator. For central properties, never condition on IsTestProject in Directory.Build.props; use a property already available there, such as MSBuildProjectName.

Important: Do not mix VSTest-based and MTP-based .NET test projects in the same solution or run configuration -- this is an unsupported scenario.

When to Use

• Switching from VSTest to Microsoft.Testing.Platform for any supported test framework
• Enabling dotnet run / dotnet watch / direct executable execution for test projects
• Enabling Native AOT or trimmed test execution
• Replacing vstest.console.exe with dotnet test on MTP
• Updating CI/CD pipelines from the VSTest task to the .NET Core CLI task
• Updating dotnet test arguments from VSTest syntax to MTP syntax

When Not to Use

• The project already runs on Microsoft.Testing.Platform and there is no remaining MTP behavioral difference to resolve (e.g., exit code 8 for zero tests discovered)
• Migrating between test frameworks (e.g., MSTest to xUnit.net) -- different effort entirely
• The project builds UWP or packaged WinUI test projects -- MTP does not support these yet
• The solution mixes .NET and non-.NET test adapters (e.g., JavaScript or C++ adapters) -- VSTest is required
• Upgrading MSTest versions -- use migrate-mstest-v1v2-to-v3 or migrate-mstest-v3-to-v4

Inputs