public async Task Values_Get_All()
        {
            var controller = new PersonsController(new PersonService());

            var result = await controller.GetRec();

            var okResult = result.Should().BeOfType <OkObjectResult>().Subject;
            var persons  = okResult.Value.Should().BeAssignableTo <IEnumerable <Person> >().Subject;

            persons.Count().Should().Be(8);
        }