isabella232 / vssdktestfx

A testing framework for Visual Studio extensions

Visual Studio SDK Test Framework

The VS SDK Test Framework is a library for your unit tests that exercise VS code to use so that certain core VS functionality works outside the VS process so your unit tests can function. For example, ThreadHelper and obtaining global services from the static ServiceProvider tend to fail in unit tests without this library installed.

Consuming this test framework

Microsoft Internal users: See specific guidance if consuming within the VS repo.

1. Install the NuGet package Microsoft.VisualStudio.Sdk.TestFramework, or for Xunit test projects, install the more specific Microsoft.VisualStudio.Sdk.TestFramework.Xunit package

2. Make sure your unit test project generates the required binding redirects by adding these two properties to your project file:

   <AutoGenerateBindingRedirects>true</AutoGenerateBindingRedirects>
   <GenerateBindingRedirectsOutputType>true</GenerateBindingRedirectsOutputType>

3. Apply some changes to your test project source as appropriate given the test framework you're already using:

   • Xunit
   • MSTest

Main Thread considerations

This library will create a mocked up UI thread, such that ThreadHelper.JoinableTaskFactory.SwitchToMainThreadAsync() can switch to it. Your unit tests do not start on this mocked up UI thread. If your product code contains checks that it is invoked on the UI thread (e.g. ThreadHelper.ThrowIfNotOnUIThread()) your test method should look like this:

[TestMethod] // or [Fact]
public async Task VerifyWeDoSomethingGood()
{
    await ThreadHelper.JoinableTaskFactory.SwitchToMainThreadAsync();
    MyVSPackage.DoSomethingAwesome();
}

Built in service mocks

There are a collection of "base services" that the VSSDKTestFx comes with mocks for. Calling GlobalServiceProvider.AddService for any of these will result in an InvalidOperationException being thrown claiming that the service is already added.

These services include:

• SVsActivityLog Customize behavior by acquiring the service and downcasting to the MockVsActivityLog type, then setting the ForwardTo property.
• OLE.Interop.IServiceProvider
• SVsTaskSchedulerService
• SVsUIThreadInvokerPrivate

More may be added and can be found in source code.

Contributing

This project has adopted the Microsoft Open Source Code of Conduct.

See our contributing doc for more info.