使用ActionResult测试web api控制器

[ApiController]
[Route("api/[controller]")]
public class SampleController : ControllerBase
{
    [HttpGet]
    public ActionResult<string> Get()
    {
        if (DateTime.Now.Hour < 12)
        {
            return Ok("Good morning!");
        }
        else
        {
            return NotFound("It's not morning anymore.");
        }
    }
}

public class SampleControllerTests
{
    [Fact]
    public void Get_ShouldReturnGoodMorning_WhenTimeIsBeforeNoon()
    {
        // Arrange
        var controller = new SampleController();
        var clockMock = new Mock<ISystemClock>();
        clockMock.SetupGet(c => c.Now).Returns(DateTime.Today.AddHours(11));
        controller.Clock = clockMock.Object;

        // Act
        var result = controller.Get();

        // Assert
        var okResult = Assert.IsType<OkObjectResult>(result);
        Assert.Equal("Good morning!", okResult.Value);
    }

    [Fact]
    public void Get_ShouldReturnNotFound_WhenTimeIsAfterNoon()
    {
        // Arrange
        var controller = new SampleController();
        var clockMock = new Mock<ISystemClock>();
        clockMock.SetupGet(c => c.Now).Returns(DateTime.Today.AddHours(13));
        controller.Clock = clockMock.Object;

        // Act
        var result = controller.Get();

        // Assert
        var notFoundResult = Assert.IsType<NotFoundResult>(result);
        Assert.Equal("It's not morning anymore.", notFoundResult.Value);
    }
}