有“this”关键字时如何使用 xUnit 和 Moq 测试 web api 方法

如何解决有“this”关键字时如何使用 xUnit 和 Moq 测试 web api 方法

我正在尝试使用 xUnit 和 Moq 测试 web api 方法，但是出现了一种情况，因为它使用了“this”关键字。请查看代码。

Web API 接口

public interface IRepository
{
    IEnumerable<Reservation> Reservations { get; }
    Reservation this[int id] { get; }
}

有这个关键字Reservation this[int id] { get; }

Web API 控制器

[ApiController]
[Route("api/[controller]")]
public class ReservationController : ControllerBase
{
    private IRepository repository;
    public ReservationController(IRepository repo) => repository = repo;

    [HttpGet]
    public IEnumerable<Reservation> Get() => repository.Reservations;

    [HttpGet("{id}")]
    public ActionResult<Reservation> Get(int id)
    {
        if (id == 0)
            return BadRequest("Value must be passed in the request body.");

        Reservation r = repository[id];

        if (r is null)
            return NotFound();

        return Ok(r);
    }
}

Web API 提供内存中的记录，而不是数据库中的记录。有一个包含硬编码记录的类 Repository.cs。

public class Repository : IRepository
{
    private Dictionary<int,Reservation> items;

    public Repository()
    {
        items = new Dictionary<int,Reservation>();
        new List<Reservation> {
            new Reservation {Id=1,Name = "Jack",StartLocation = "Edinberg",EndLocation="Yeti" },new Reservation {Id=2,Name = "Nick",StartLocation = "Moscow",EndLocation="LKO" },new Reservation {Id=3,Name = "Ramon",StartLocation = "London",EndLocation="Paris" }
            }.ForEach(r => AddReservation(r));
    }

    public Reservation this[int id] => items.ContainsKey(id) ? items[id] : null;

    public IEnumerable<Reservation> Reservations => items.Values;

 }

现在我想模拟 web api 方法 Get(int id) 但不能因为 'this' 关键字。我尝试了下面的代码但失败了。

[Fact]
public void Test_GET_AReservations_BadRequest()
{
    // Arrange
    var mockRepo = new Mock<IRepository>();
    mockRepo.Setup(repo => repo.Reservations.this).Returns(Single());
    var controller = new ReservationController(mockRepo.Object);

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

    // Assert
    var model = Assert.IsAssignableFrom<IEnumerable<Reservation>>(result);
    Assert.Equal(3,model.Count());
}

private static Reservation Single()
{
    return new Reservation()
    {
        Id = 1,Name = "Test One",StartLocation = "SL1",EndLocation = "EL1"
    };
}

要查找的模拟代码是 mockRepo.Setup(repo => repo.Reservations.this).Returns(Single());。我得到编译错误。所以请帮我修复它。

解决方法

为了重新创建所需的行为，您可以在 Returns 中捕获传递的参数并使用它来创建假模型

[Fact]
public void Should_GET_AReservation_By_Id() {
    // Arrange
    var mockRepo = new Mock<IRepository>();
    mockRepo.Setup(repo => repo[It.IsAny<int>()])
        .Returns((int id) => Single(id));

    var controller = new ReservationController(mockRepo.Object);
    int id = 123456

    // Act
    ActionResult<Reservation> result = controller.Get(id);
    Reservation actual = result.Value;

    // Assert
    actual.Should().NotBeNull();
    actual.Id.Should().Be(id);
}

private static Reservation Single(int id) =>
    return new Reservation() {
        Id = id,Name = "Test One",StartLocation = "SL1",EndLocation = "EL1"
    };

注意使用 It.IsAny<int> 参数匹配器来接受传递给索引器的任何整数。

,

这可能对您有用：

mockRepo
    .SetupSet(repo => repo[123456] = It.IsAny<int>())
    .Callback((string name,object m) => {Single()});

来源：https://weblogs.asp.net/bleroy/mocking-indexer-setters-with-moq