Skip to content

LightInject.xUnit

LightInject.xUnit provides an integration that enables dependency injection in xUnit test methods.

Installing

LightInject.xUnit provides two distribution models via NuGet

Binary

PM> Install-Package LightInject.xUnit

This adds a reference to the LightInject.Xunit.dll in the target project.

Source

PM> Install-Package LightInject.xUnit.Source

This will install a single file, LightInject.Xunit.cs in the target project.

Injecting services

Services from LightInject are injected into methods that are decorated with the InjectData attribute.

[Theory, InjectData]                
public void TestMethod(IFoo foo)
{
    Assert.NotNull(foo);
}

Configuration

LightInject will look for an ICompositionRoot implementation in the same assembly as the requested service. If it is found, it will be executed and the container gets configured through that composition root.

If such an implementation does not exists or that we for some other reason need to configure the container, we can do this by simply implementing a static method in the test class with the following signature.

public static void Configure(IServiceContainer container)
{
    container.Register<IFoo, Foo>();            
}

This method is executed regardless of other composition roots and allows customized configuration of the container before the test is executed.

Scoping (xUnit <= 1.9.2)

Services registered with the PerScopeLifetime or PerRequestLifetime needs to be resolved within an active Scope to ensure that any services that implements IDisposable are properly disposed.

By decorating the test method with the ScopedTheory attribute, a new Scope will be started when the test method starts and it will end when the test method ends.

[ScopedTheory, InjectData]
public void MethodWithScopedArgument(IFoo foo)
{
    Assert.NotNull(foo);
}

Scoping (xUnit >= 2.0.0)

Services registered with the PerScopeLifetime or PerRequestLifetime needs to be resolved within an active Scope to ensure that any services that implements IDisposable are properly disposed.

By decorating the test method with the Scoped attribute, a new Scope will be started when the test method starts and it will end when the test method ends.

[Theory, Scoped, InjectData]
public void MethodWithScopedArgument(IFoo foo)
{
    Assert.NotNull(foo);
}