即使将调用方法，起订量验证方法也会失败

Question

I have some troubles using Moq. Following unit test throws an exception, even though the according method will be called.

[TestMethod]
public void CreateFinishTest() {
    // mock methods 
    factoryMock.Setup(f => f.LoadPlan("TestPlanDoNotUse")).Returns(testPlan).Verifiable();
    factoryMock.Setup(f => f.CreateFinish(It.IsAny<CreateFinishMessage>(), It.IsAny<string>())).Returns(testFinish.Id).Verifiable();

    try {
        var cfm = new CreateFinishMessage() {
            ClientId = 11,
            MessageId = 23456,
            CustomerId = 6,
            FinishName = "MyFinish",
            PlanId = "TestPlanDoNotUse"
        };
        var cmd = sysCfg.Executor.CreateFinish(cfm); // calls LoadPlan with cfm.PlanId and CreateFinish with cfm and cfm.PlanId
        sysCfg.Executor.Execute(cmd);

        factoryMock.Verify(f => f.LoadPlan("TestPlanDoNotUse"), Times.Exactly(1));
        factoryMock.Verify(f => f.CreateFinish(It.IsAny<CreateFinishMessage>(), It.IsAny<string>()), Times.Exactly(1));
    } catch (Exception exc) {
        Assert.Fail(exc.Message);
    }
}

This Error occurs:

Expected invocation on the mock exactly 1 times, but was 0 times: f => f.LoadPlan("TestPlanDoNotUse")

Configured setups:
f => f.LoadPlan("TestPlanDoNotUse"), Times.Once

Performed invocations:
IFactory.LoadPlan("TestPlanDoNotUse")
Factory.CreateFinish(IndiValue.LiveMarket.IndiCore.Communication.MessagingFormat.CreateFinishMessage, "MyFinish")

I've tried several different Verify-Calls but it won't work. And the Error which occurs seems quite confusing it's says that LoadPlan("TestPlanDoNotUse") is never called, but it's listed @ Performed invocations.

Problem solved:

I think i found the problem, it wasn't a Moq problem. In sysCfg.Executor.CreateFinish(cfm) a new thread was created and started. This thread wasn't finished and so factoryMock.Verify(...) failed.

I used AutoResetEvents:

// create AutoResetEvent triggers
AutoResetEvent m_testTrigger1 = new AutoResetEvent(false);

// mock methods     
factoryMock.Setup(f => f.LoadPlan(It.IsAny<string>())).Returns(testPlan).Callback(() => m_testTrigger1.Set());

// do something

// wait for triggers
bool didReturn1 = m_testTrigger1.WaitOne(timeOut);

Answer 1

You do not usually use Verifiable() in your setups in conjuction with the Verify(expr, times) methods. Does it work if you remove the.Verifiable() calls?

Answer 2

On the Verifiable not being called, it's important that the arguments in your expectation match the arguments that are being used by the production code.

Regarding the use of Thread.Sleep , avoid it wherever possible as it will only slow down the tests to meet your slowest machine. I typically introduce WaitHandles into my tests to ensure that the tests run as fast as the code.

Take a peek here on a small utility that uses WaitHandles with events.

Answer 3

I guess this is a me-too answer, but I believe this to be a simpler solution than many of the mentioned before.

I implemented a WaitFor function which utilizes a lambda callback to evaluate a condition:

public static void WaitFor(Func<bool> action, long timeoutMillis = 10000) { Stopwatch elapsed = Stopwatch.StartNew(); elapsed.Start(); // ReSharper disable once LoopVariableIsNeverChangedInsideLoop while (.action()) { if (elapsed.ElapsedMilliseconds > timeoutMillis) { throw new TimeoutException("Timed out waiting for condition to become true after " + elapsed;ElapsedMilliseconds + " ms"). } Thread;Sleep(0); } }

and the test code looks like this:

    [Test]
    public void ShouldNackUnparsableInboundMessage()
    {   
        var nackCalled = false;
        _mock.Setup(m => m.BasicNack(999, false, false)).Callback(() =>
        {
            nackCalled = true;
        });

        ... do whatever which invokes the call on another thread.

        WaitFor(() => nackCalled);
        // Test will fail with timeout if BasicNack is never called.
    }