Question

在过去的几年里，我一直在使用Moq来满足我的嘲弄需求，但在看了FakeItEasy之后我想尝试一下。

我经常想测试一个方法是否使用正确的参数调用，但我发现FakeItEasy没有令人满意的方法。

我有以下代码要测试：

    public class WizardStateEngine : IWizardStateEngine
{
    private readonly IWorkflowInvoker _workflowInvoker;
    private List<CustomBookmark> _history;

    public WizardStateEngine(IWorkflowInvoker workflowInvoker)
    {
        _workflowInvoker = workflowInvoker;
    }

    public void Initialize(List<CustomBookmark> history)
    {
        _history = history;
    }

    public WizardStateContext Execute(Command command, WizardStateContext stateContext, CustomBookmark step)
    {
        Activity workflow = new MyActivity();
        var input = new Dictionary<string, object>();
        input["Action"] = command;
        input["Context"] = stateContext;
        input["BookmarkHistory"] = _history;

        var output = _workflowInvoker.Invoke(workflow, input);

        _history = output["BookmarkHistory"] as List<CustomBookmark>;

        return output["Context"] as WizardStateContext;
    }

    public List<CustomBookmark> GetBookmarkHistory()
    {
        return _history;
    }
}

我想编写一些测试来验证_workflowInvoker.Invoke（）的输入。我的TestInitialize方法设置所需的资源，并将输入字典保存为_workflowInvoker.Invoke（）作为本地字段_wfInput。

    [TestInitialize]
    public void TestInitialize()
    {
        _wizardStateContext = new WizardStateContext();
        _workflowInvoker = A.Fake<IWorkflowInvoker>();
        _wizardStateEngine = new WizardStateEngine(_workflowInvoker);

        _outputContext = new WizardStateContext();
        _outputHistory = new List<CustomBookmark>();
        _wfOutput = new Dictionary<string, object>
                        {{"Context", _outputContext}, {"BookmarkHistory", _outputHistory}};

        _history = new List<CustomBookmark>();

        A.CallTo(() =>
                 _workflowInvoker.Invoke(A<Activity>.Ignored, A<Dictionary<string, object>>.Ignored))
            .Invokes(x => _wfInput = x.Arguments.Get<Dictionary<string, object>>("input"))
            .Returns(_wfOutput);

        _wizardStateEngine.Initialize(_history);
    }

设置完成后，我有多个这样的测试：

    [TestMethod]
    public void Should_invoke_with_correct_command()
    {
        _wizardStateEngine.Execute(Command.Start, null, null);

        ((Command) _wfInput["Action"]).ShouldEqual(Command.Start);
    }

    [TestMethod]
    public void Should_invoke_with_correct_context()
    {
        _wizardStateEngine.Execute(Command.Start, _wizardStateContext, null);

        ((WizardStateContext) _wfInput["Context"]).ShouldEqual(_wizardStateContext);
    }

    [TestMethod]
    public void Should_invoke_with_correct_history()
    {
        _wizardStateEngine.Execute(Command.Start, _wizardStateContext, null);

        ((List<CustomBookmark>) _wfInput["BookmarkHistory"]).ShouldEqual(_history);
    }

我不喜欢TestInitialize中的魔术字符串“input”来获取传递的参数（或幻数）。我可以在没有本地字段的情况下编写测试：

    [TestMethod]
    public void Should_invoke_with_correct_context()
    {
        _wizardStateEngine.Execute(Command.Start, _wizardStateContext, null);

        A.CallTo(() =>
                 _workflowInvoker.Invoke(A<Activity>._,
                                         A<Dictionary<string, object>>.That.Matches(
                                             x => (WizardStateContext) x["Context"] == _wizardStateContext)))
            .MustHaveHappened();
    }

但我发现本地字段的测试更具可读性。

有没有办法将输入设置为我的测试类中没有幻数或字符串的字段？

我希望问题中的更新示例显示我为什么要使用本地字段。如果我能找到一个很好的可读方式，我非常愿意在没有本地字段的情况下编写我的测试。

Answer 1

A.CallTo(() => service.DoSomething(A<int>.That.Matches(x => x == 100)))
 .MustHaveHappened();

Answer 2

我同意达林所说的一切，做你正在做的事似乎是一种坏习惯。你说这个琐碎的例子看起来“愚蠢”，你能提供一个看起来很聪明的例子吗？

无论如何，以下测试与Moq测试具有完全相同的行为：

[Test]
public void Should_do_something_with_correct_input()
{
    int inputNumber = 0;

    var service = A.Fake<IService>();
    A.CallTo(() => service.DoSomething(A<int>._))
        .Invokes((int x) => inputNumber = x);

    var system = new System(service);
    system.InvokeService();

    inputNumber.ShouldEqual(100);
}

在不使用魔术字符串的情况下将参数传递给FakeItEasy-mock？

2 个答案: