CallBase should not be allowed for delegate mocks

[stakx]

Reproduction code:

var mock = new Mock<Action>();
mock.Setup(m => m()).CallBase();
mock.Object.Invoke();

Actual behavior:

mock.Object.Invoke() throws a NotImplementedException with message:

This is a DynamicProxy2 error: The interceptor attempted to 'Proceed' for method 'Void Invoke()' which has no target. When calling method without target there is no implementation to 'proceed' to and it is the responsibility of the interceptor to mimic the implementation (set return value, out arguments etc)

Expected behavior:

The call to .CallBase() should throw a NotSupportedException with a message explaining that CallBase cannot be used with delegate mocks.

The same should happen when setting a delegate mock's CallBase property to true.

[m-wild]

Hey, created PR #708

[stakx]

@tehmantra, thank you for picking this one up! 👍 I've posted a review on your PR.

(P.S.: On a totally unrelated note, please say hello to Auckland and the whole Hauraki Gulf for me. Wish I were there.)

[viktor-nikolaev]

It looks like something is wrong with this issue.

I have this code

[Theory]
[AutoMoqData]
internal async Task GetAutomationStatistics_should_return_correct_statistics(
  [Frozen] Mock<GetAutomationsLogTotalCount> getAutomationsLogTotalCount,
  [Frozen] GetCurrentlyRunningSchedulesResult getCurrentlyRunningSchedulesResult,
  [Frozen] GetAutomationsTotalCountResult getAutomationsTotalCountResult,
  GetAutomationStatisticsQuery query,
  GetAutomationStatisticsHandler sut,
  CancellationToken ct
)
{
  getAutomationsLogTotalCount
    .Setup(_ => _(It.IsAny<GetAutomationsLogTotalCountQuery>(), ct))
    .ReturnsAsync((GetAutomationsLogTotalCountQuery x, CancellationToken _) =>
      new GetAutomationsLogTotalCountResult
      {
        TotalCount = (long) x.LogLevel.GetValueOrDefault()
      }
    );

  var expectedResult = new GetAutomationStatisticsResult
  {
    AutomationsRunningNow = await getCurrentlyRunningSchedulesResult.Items.LongCount(ct),
    TotalAutomations = getAutomationsTotalCountResult.TotalCount,
    ErrorsReported = (long) EapLogLevel.Error,
    WarningsReported = (long) EapLogLevel.Warn,
  };

  var result = await sut.Handle(query, ct);

  result.Should().BeEquivalentTo(expectedResult);
}

Where GetAutomationsLogTotalCount is a delegate. And I got the exception

AutoFixture.ObjectCreationExceptionWithPath : AutoFixture was unable to create an instance from Moq.Mock`1[AutomationsWeb.Features.Statistics.GetAutomationsLogTotalCount] because creation unexpectedly failed with exception. Please refer to the inner exception to investigate the root cause of the failure.

Request path:
	Moq.Mock`1[AutomationsWeb.Features.Statistics.GetAutomationsLogTotalCount] getAutomationsLogTotalCount
	  Moq.Mock`1[AutomationsWeb.Features.Statistics.GetAutomationsLogTotalCount]

Inner exception messages:
	System.NotSupportedException: CallBase cannot be used with Delegate mocks.

But I do not call CallBase method.

[zvirja]

@Veikedo Notice, it has been fixed in AutoFixture. Please update to a new version (it will be published soon) to get a fix 😉