[Fact]
public void Post_PersonWithoutName_PersonNotSaved()
{
    // Create new person, without a name, which will not be accepted by the controller
    var person = new Person();
    
    // Create new controller with mock repository
    var controller = new PersonController(this._repository.Object);
    
    // Call controller to post person
    var result = controller.Post(person);

    // Assert
    result.Should().BeOfType<BadRequestObjectResult>();
    
    result.As<BadRequestObjectResult>()
        .Value.Should().Be("Person has invalid state");
    
    this._repository.Verify(r => r.Add(It.IsAny<Person>()), Times.Never);
}