C# Fixture Classes

Test.cs

public class FooServiceTests
{
    private Fixture _fixture = new Fixture();
    
    [Test]
    public void WhenLoggedIn_TheReportHasTheUsersNameIncluded()
    {
        var subject = _fixture.LogIn("George Washington").CreateService();
        var result = subject.GetReportData();
        Check.That(result.CurrentUserName).IsEqualTo("George Washington");
    }
    
    private class Fixture
    {
        public IDependency MockDependency = new Mock<IDependency>();
        
        public Fixture LogIn(string name)
        {
            MockDependency.SetUp(m => m.GetCurrentUser()).Returns(name);
            return this;
        }
        
        public FooService CreateService()
        {
            return new FooService(MockDependency.Object);
        }
    }
}