AutoFixture AutoMoq 不使用我的属性模拟

Question

我有一个要测试的抽象类。这个类中有一个抽象属性用于我的 DAO，我在继承的类中定义。

public abstract class DeviceGroupManagerBase<TDeviceGroup> where TDeviceGroup : DeviceGroup 
{
    protected abstract IDeviceGroupDao<TDeviceGroup> DeviceGroupDao { get; }

    public TDeviceGroup UpdateDeviceIndexes(Device device)
    {
        return DeviceGroupDao.GetDeviceGroup(device.Group.Id);
    }
}

我想测试 Updatedeviceindexes 方法，因此我试图模拟一个名为 DeviceGroupDao 的属性。

[TestFixture]
[Category("Unit")]
public class DeviceGroupManagerBaseTests
{
    private IFixture fixture;
    private Mock<DeviceGroupManagerBase<DeviceGroup>> subject;
    private Mock<IDeviceGroupDao<DeviceGroup>> deviceGroupDaoMock;
    private DeviceGroupManagerBase<DeviceGroup> Manager => subject.Object;

    [TestFixtureSetUp]
    public void Init()
    {
        fixture = new Fixture().Customize(new AutoMoqCustomization());
        deviceGroupDaoMock = fixture.Freeze<Mock<IDeviceGroupDao<DeviceGroup>>>();
        subject = fixture.Freeze<Mock<DeviceGroupManagerBase<DeviceGroup>>>();
    }

    [Test]
    public void TestUpdateDeviceIndexes()
    {
        var device = fixture.Create<Device>();
        var deviceGroup = fixture.Create<DeviceGroup>();

        deviceGroupDaoMock.Setup(x => x.GetDeviceGroup(It.IsAny<int>())).Returns(deviceGroup);

        var result = Manager.UpdateDeviceIndexes(device);
        // The resultDeviceGroup will not be contain a previously defined object

        Assert.AreEqual(deviceGroup.Id, result.Id);
    }
}

我也尝试以这种方式为我的设备对象添加注册：

fixture.Register(() => deviceGroup);

但我仍然得到一个新对象。

如何模拟IDeviceGroupDao<TDeviceGroup>？

Answer 1

由于DeviceGroupManagerBase 是一个抽象基类，您需要一个SUT Double。如果您将DeviceGroupDao 属性设为public，则最容易做到：

public abstract class DeviceGroupManagerBase<TDeviceGroup> where TDeviceGroup : DeviceGroup
{
    public abstract IDeviceGroupDao<TDeviceGroup> DeviceGroupDao { get; }

    public TDeviceGroup UpdateDeviceIndexes(Device device)
    {
        return DeviceGroupDao.GetDeviceGroup(device.Group.Id);
    }
}

否则，您将需要使用 Moq 的 API 来定义和覆盖 protected 成员，这是可能的，但需要做更多工作。

那么你需要覆盖subject的DeviceGroupDao属性：

subject.SetupGet(x => x.DeviceGroupDao).Returns(deviceGroupDaoMock.Object);

这是完整的测试：

[TestFixture]
[Category("Unit")]
public class DeviceGroupManagerBaseTests
{
    private IFixture fixture;
    private Mock<DeviceGroupManagerBase<DeviceGroup>> subject;
    private Mock<IDeviceGroupDao<DeviceGroup>> deviceGroupDaoMock;
    private DeviceGroupManagerBase<DeviceGroup> Manager => subject.Object;

    [OneTimeSetUp]
    public void Init()
    {
        fixture = new Fixture().Customize(new AutoMoqCustomization());
        deviceGroupDaoMock = fixture.Freeze<Mock<IDeviceGroupDao<DeviceGroup>>>();
        subject = fixture.Freeze<Mock<DeviceGroupManagerBase<DeviceGroup>>>();
        subject.SetupGet(x => x.DeviceGroupDao).Returns(deviceGroupDaoMock.Object);
    }

    [Test]
    public void TestUpdateDeviceIndexes()
    {
        var device = fixture.Create<Device>();
        var deviceGroup = fixture.Create<DeviceGroup>();

        deviceGroupDaoMock.Setup(x => x.GetDeviceGroup(It.IsAny<int>())).Returns(deviceGroup);

        var result = Manager.UpdateDeviceIndexes(device);

        Assert.AreEqual(deviceGroup.Id, result.Id);
    }
}

这现在在我的机器上传递。

Answer 2

因为DeviceGroupDao 受到保护，您需要找到一种从外部访问它的方法。创建一个允许您为其设置值的存根。

public class DeviceGroupManagerBaseStub<TDeviceGroup> 
    : DeviceGroupManagerBase<TDeviceGroup> where TDeviceGroup : DeviceGroup {

    private IDeviceGroupDao<TDeviceGroup> deviceGroupDao;

    public DeviceGroupManagerBaseStub(IDeviceGroupDao<TDeviceGroup> deviceGroupDao) {
        this.deviceGroupDao = deviceGroupDao;
    }

    protected override IDeviceGroupDao<TDeviceGroup> DeviceGroupDao {
        get {
            return deviceGroupDao;
        }
    }
}

然后您可以模拟 IDeviceGroupDao<TDeviceGroup> 并将其注入存根中进行测试。