Verify behavior change using DefaultValue.Mock 4.12.0 vs 4.13.0

[DesrosiersC]

Hi,

I have a set of unit tests which start failing after upgrade from Moq 4.12.0 to 4.13.0.
Here's code which illustrates the issue:

using System;
using System.Collections.Generic;
using Moq;

namespace MoqRegression
{
	internal static class Program
	{
		private static void Main( string[] args )
		{
			var totoMock = new Mock<IToto>();
			totoMock.DefaultValue = DefaultValue.Mock;

			totoMock.Setup( o => o.Do() )
				.Verifiable();

			totoMock.Object.Do();

			totoMock.Verify();

			Console.ReadLine();
		}
	}

	public interface IToto
	{
		IList<string> Do();
	}
}

The verify fails from version 4.1.13.0 and above.

Could you please let me know if the change of behavior is a bug and if I should wait for the fix.

Thanks,
Christian

[stakx]

Thanks for reporting. Looks like a bug. I'll take a look as soon as I find a free moment.

[stakx]

This should be fixed in Moq version 4.14.2 (which has just become available on NuGet). Thanks again for reporting this regression, @DesrosiersC!

[DesrosiersC]

Hi,

Thanks @stakx for being so responsive!

Moq is a great product and it is good to see it is so well maintained.

[stakx]

Thanks for the kind feedback! ❤️

[DesrosiersC]

Hi,

@stakx
The fix is OK for the initial example but I'm still experiencing a breaking change for the example below.

using System;
using System.Collections.Generic;
using Moq;

namespace MoqRegression
{
	internal static class Program
	{
		private static void Main( string[] args )
		{
			var totoMock = new Mock<IToto>();
			var tataMock = new Mock<ITata>();
			tataMock.DefaultValue = DefaultValue.Mock;

			totoMock.Setup( o => o.DoToto() )
				.Returns( tataMock.Object )
				.Verifiable();

			totoMock.Object.DoToto();
			tataMock.Object.DoTata();

			totoMock.Verify();

			Console.WriteLine( "Success!" );
			Console.ReadLine();
		}
	}

	public interface IToto
	{
		ITata DoToto();
	}

	public interface ITata
	{
		IList<string> DoTata();
	}
}

The verify fails from version 4.14.0 and above.

Thanks in advance for taking a look at this,
Christian

[stakx]

@DesrosiersC — Thanks again for the report. I see, I wasn't quite thorough enough.

Note to self, I suspect the problem lies (once again) here:

https://github.com/moq/moq4/blob/a20d1df93b678edc413ef8f0865a70c79d15dae9/src/Moq/Interception/InterceptionAspects.cs#L264-L268

Could be that the setup being added (the one for the auto-mocked return value) doesn't get marked as matched right away.

[connywesth]

I'm pretty newbie at Moq at all, so I may not have understood the problem, but this code I got to work:

`using System;
using System.Collections.Generic;
using Moq;

namespace MoqRegression
{
internal static class Program
{
private static void Main(string[] args)
{
Mock totoMock = new Mock();
Mock tataMock = new Mock();
Mock tataListMock = new Mock();

		totoMock.DefaultValue = DefaultValue.Mock;
		tataMock.DefaultValue = DefaultValue.Mock;
		tataListMock.DefaultValue = DefaultValue.Mock;

		totoMock.Setup(o => o.DoToto())
			.Returns(tataMock.Object)
			.Verifiable();

		tataMock.Setup(o => o.DoTataList())
			.Returns(tataListMock.Object)
			.Verifiable();

		totoMock.Object.DoToto();
		tataMock.Object.DoTataList();

		totoMock.Verify();
		tataMock.Verify();

		Console.WriteLine("Success!");
		Console.ReadLine();
	}
}

public interface IToto
{
	ITata DoToto();
}

public interface ITata
{
	ITataList DoTataList();
}
public interface ITataList : IList<string>
{
}

}`

[DesrosiersC]

Thanks for your help @connywesth .
The problem is that I do not wish to declare nor verify the second mock. Also I have lots of tests failing because of this behaviour change and it would be quite a job to change them all.

[stakx]

@DesrosiersC, another fixed package version 4.14.3 should become available on NuGet shortly. Hopefully, this time it's fixed for real. 😃 If you find anything else amiss, please don't hesitate to report it.

[DesrosiersC]

@stakx , thanks for taking the time to look at this. It is much appreciated.
It works perfectly now!