public void WithWork_should_clone_not_modify() { var sut = new User("1234567890", "Karo Hero", "Meisterhirte"); var clone = sut.WithWork("alter Meisterhirte"); clone.Should().NotBe(sut); clone.Should().NotBeEquivalentTo(sut); clone.Work.Should().Be("alter Meisterhirte"); sut.Work.Should().Be("Meisterhirte"); }