DivertR 3.0.0

DivertR

DivertR is a .NET library for creating proxy test doubles such as mocks, fakes and spies. It is similar to mocking frameworks like the well known Moq but provides, in addition, features for integration and component testing of wired-up systems.

Installing

Install DivertR as a NuGet package:

Install-Package DivertR

Or via the .NET command line interface:

dotnet add package DivertR

Example Usage

DivertR can facilitate a style of testing where you start with a dependency injection wired-up system and mock out specific parts per test. For example, it can be used to write tests on a WebApp like this:

[Fact]
public async Task GivenFooExistsInRepo_WhenGetFoo_ThenReturnsFoo_WithOk200()
{
    // ARRANGE
    var foo = new Foo
    {
        Id = Guid.NewGuid(),
        Name = "Foo123"
    };

    _diverter
        .Redirect<IFooRepository>() // Redirect IFooRepository calls 
        .To(x => x.GetFooAsync(foo.Id)) // matching this method and argument
        .Via(() => Task.FromResult(foo)); // via this delegate

    // ACT
    var response = await _fooClient.GetFooAsync(foo.Id);
    
    // ASSERT
    response.StatusCode.ShouldBe(HttpStatusCode.OK);
    response.Content.Id.ShouldBe(foo.Id);
    response.Content.Name.ShouldBe(foo.Name);
}

[Fact]
public async Task GivenFooRepoException_WhenGetFoo_ThenReturns500InternalServerError()
{
    // ARRANGE
    _diverter
        .Redirect<IFooRepository>()
        .To(x => x.GetFooAsync(Is<Guid>.Any))
        .Via(() => throw new Exception());

    // ACT
    var response = await _fooClient.GetFooAsync(Guid.NewGuid());

    // ASSERT
    response.StatusCode.ShouldBe(HttpStatusCode.InternalServerError);
}

Resources

• Documentation and quickstart guide
• Discussion - Feedback and comments are welcome
• DivertR NuGet package