FakeItEasy FixtureInitialization sample

FixtureInitializationSample.cs

public class FixtureInitializationSample
{
    public interface IFoo
    {
        string Boo();
    }

    public class SystemUnderTest
    {
        private readonly IFoo foo;

        public SystemUnderTest(IFoo foo)
        {
            this.foo = foo;
        }

        public string Double()
        {
            return foo.Boo() + foo.Boo();
        }
    }

    [UnderTest]
    private SystemUnderTest sut;

    [Fake]
    private IFoo fakeFoo;

    [Test]
    public void Double_should_double_the_boo_of_foo()
    {
        Fake.InitializeFixture(this); // could be in setup

        A.CallTo(() => fakeFoo.Boo()).Returns("Boo who?");

        Assert.That(sut.Double(), Is.EqualTo("Boo who?Boo who?"));
    }
}