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Arash A. Sabet
Arash A. Sabet

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Xunit Dependency Injection

Xunit does not come with any built-in dependency injection features, therefore developers have to come up with their own solution to recruit their favourite dependency injection frameworks in their tests.

This library brings in Microsoft's dependency injection container to Xunit by leveraging fixtures.

Xunit Dependency Injection library is an open source project on Github whose official page is available here.

Get started

Nuget package

First add the nuget package to your Xunit project:

Install-Package Xunit.Microsoft.DependencyInjection
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Setup your fixture

There is an abstract class called Xunit.Microsoft.DependencyInjection.Abstracts.TestBedFixture which contains the necessary functionalities to add services and configurations to Microsoft's dependency injection container. Your concrete test fixture class derived from this abstract class must implement the following two abstract methods:

protected abstract string GetConfigurationFile();
protected abstract void AddServices(IServiceCollection services, IConfiguration configuration);
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GetConfigurationFile(...) method returns the name of the configuration file in your Xunit test project. AddServices(...) is used to wire up services.

Access the wired up services

There are two method that you can use to access the wired up service depending on your context:

public T GetScopedService<T>(ITestOutputHelper testOutputHelper);
public T GetService<T>(ITestOutputHelper testOutputHelper);
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Adding custom logging provider

Test developers can add their own desired logger provider by overriding AddLoggingProvider(...) virtual method defined in TestBedFixture class.

Preparing Xunit test classes

Your Xunit test class must be derived from Xunit.Microsoft.DependencyInjection.Abstracts.TestBed<T> class where T should be your fixture class derived from TestBedFixture.

Also, the test class should be decorated by the following attribute:

[CollectionDefinition("Dependency Injection")]
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Running tests in order

The library has a bonus feature that simplifies running tests in order. The test class does not have to be derived from TestBed<T> class though and it can apply to all Xunit classes.

Decorate your Xunit test class with the following attribute and associate TestOrder(...) with Factand Theory:

[TestCaseOrderer("Xunit.Microsoft.DependencyInjection.TestsOrder.TestPriorityOrderer", "Xunit.Microsoft.DependencyInjection")]
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Examples

Please follow this link to view a couple of examples on utilizing this library.

One more thing

Do not forget to include the following nuget packages in your Xunit project:

    <PackageReference Include="Microsoft.Extensions.DependencyInjection" Version="3.1.10" />
    <PackageReference Include="Microsoft.Extensions.Configuration" Version="3.1.10" />
    <PackageReference Include="Microsoft.Extensions.Options" Version="3.1.10" />
    <PackageReference Include="Microsoft.Extensions.Configuration.Binder" Version="3.1.10" />
    <PackageReference Include="Microsoft.Extensions.Configuration.FileExtensions" Version="3.1.10" />
    <PackageReference Include="Microsoft.Extensions.Configuration.Json" Version="3.1.10" />
    <PackageReference Include="Microsoft.Extensions.Logging" Version="3.1.10" />
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A note on .NET 5.0

We are doing away with .NET 5.0 and instead we will be supporting .NET 6.0 once its first release version becomes available to the public.

Build Status

Nuget

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