最小起订量测试方法 C#ASP.NET MVC

Question

我研究用 moq 编写一个模块测试，这个简单的测试失败了

消息：测试方法 UnitTests.AdminTests.IndexContainPlayerList 抛出 异常：System.NullReferenceException：

[TestMethod]
    public void IndexContainPlayerList()
    {
        //Arrange
        Mock<IPlayerRepository> mock = new Mock<IPlayerRepository>();
        mock.Setup(m => m.Players).Returns(new List<Player>() {
            new Player () { Id = 1, Name = "Karye", Surname = "Irving", Team = new Team(){ Id = 1, Name = "Boston Celtics" }, TeamId = 1 },
            new Player () { Id = 1, Name = "Stephan", Surname = "Carry", Team = new Team(){ Id = 2, Name = "Golden State Warriors" }, TeamId = 2 }
        });

        AdminController target = new AdminController(mock.Object, null);

        //Action
        Player[] resultList = ((IEnumerable<Player>)target.Index().ViewData.Model).ToArray();

        //Assert
        Assert.AreEqual(resultList.Length, 2);
    }

我正在测试的方法

 public ViewResult Index()
    {
        ViewBag.ChoosingTeam = new SelectList(teamRepository.Teams, "Name ", "Name");
        return View(playerRepository.Players.ToList());
    }

为什么试运行失败，可能是我丢失了什么或不明白？

Answer 1

NullReferenceException 被抛出是因为您将null 传递给您的AdminController，我假设是为了您的ITeamsRepository。

如您所见，您正在尝试访问teamRepository，因为它为空，所以正在抛出NullReferenceException。

您还需要模拟该依赖项。
示例：

Mock<ITeamsRepository> teamsMock = new Mock<ITeamsRepository>();
AdminController target = new AdminController(mock.Object, teamsMock.Object);