如何使用moq在xunit中测试返回IEnumerable<model>的异步Task<IActionResult>？

Question

我希望测试我的控制器的GetMoviesAsync方法。在我的Moq设置中，我不知道哪里出错了。我从GetMoviesAsync中得到0个项目。

我做错了什么？

// API控制器：

   public interface ICommand
   {
        Task<IEnumerable<Movie>> GetMoviesAsync();
   }

   public class SampleController : ControllerBase
    {
        private readonly ICommand movieCommand;

        public SampleController(ICommand command)
        {
            movieCommand = command;
        }

        [HttpGet]
        public async Task<IActionResult> GetMoviesAsync()
        {
            var movies = await movieCommand.GetMoviesAsync();
            return Ok(movies);
        }
    }

// 单元测试：

public class SampleControllerTest
    {
        private IEnumerable<Movie> MovieList()
        {
            IList<Movie> movies = new List<Movie>()
            {
                new Movie()
                {
                    ID =1,
                    Title = "Test",
                    ReleaseDate = DateTime.Now,
                    RunningTimeInMinutes = 100
                }
            };
            return movies;
        }

        private SampleController GetSampleController()
        {
            var command = new Mock<ICommand>();

            return new SampleController(command.Object);
        }

        [Fact]
        public async Task GetMovies_Test()
        {
            // Arrange
            var controller = GetSampleController();
            var commadMock = new Mock<ICommand>();
            // How to setup moq here?
            commadMock.Setup(s => s.GetMoviesAsync()).Returns(Task.FromResult<IEnumerable<Movie>>(MovieList())).Verifiable();
            // Act
            var response = await controller.GetMoviesAsync() as OkObjectResult;
            // Problem is here, 
            var li=response.Value as IEnumerable<Movie>;
         }
    }

- MSR

Answer 1

我做错了什么？

使用了两个完全不同的模拟。

其中一个用于创建控制器。

private SampleController GetSampleController()
{
    var command = new Mock<ICommand>();

    return new SampleController(command.Object);
}

另一台计算机正在进行创建并在测试中进行设置。

var controller = GetSampleController();
var commadMock = new Mock<ICommand>();
// How to setup moq here?
commadMock.Setup(s => s.GetMoviesAsync()).Returns(Task.FromResult<IEnumerable<Movie>>(MovieList())).Verifiable();

为了解决这个问题，使用相同的模拟来获得所需的行为。

[Fact]
public async Task GetMovies_Test() {
    // Arrange
    var commadMock = new Mock<ICommand>();
    var controller = new SampleController(commadMock.Object); //<---
    commadMock
        .Setup(_ => _.GetMoviesAsync())
        .ReturnsAsync(MovieList())
        .Verifiable();

    // Act
    var response = await controller.GetMoviesAsync() as OkObjectResult;

    //Assert
    var list = response.Value as IEnumerable<Movie>;

    //...
 }

请注意使用ReturnsAsync设置返回的Task。

- Nkosi

Answer 2

对我来说，Nkosi提供的解决方案几乎有帮助，但有一点不同

[Fact]
public async Task GetMovies_Test() {
    // Arrange
    var commadMock = new Mock<ICommand>();
    var controller = new SampleController(commadMock.Object); //<---
    commadMock
        .Setup(_ => _.GetMoviesAsync())
        .ReturnsAsync(MovieList());

    // Act
    var response = await controller.GetMoviesAsync();

    //Assert
    var returnValue = Assert.IsType<ViewResult>(response);

    var model = returnValue.Model as IEnumerable<Movie>;

    //...
 }

- Yehor Karachetsev

Answer 3

看起来你在控制器上没有使用正确的模拟。你正在使用的那个没有在 GetMoviesAsync 方法之上进行任何设置。

- Vitor Paulino