CODEWITHSUNDEEP
c#.netunit-testingnunitrhino-mocks
Jordy
Jordy

Reputation: 661

How to solve System.InvalidOperationException from RhinoMocks?

For testing purposes I'm using NUnit and RhinoMocks. An error occured yesterday and I cannot get it solved. I searched the internet for a solution. I found a lot possible solutions, but in my case it doesn't solve the issue.

The exception stack trace:

   System.InvalidOperationException : Previous method 'IContainer.GetImageHandler();' requires a return value or an exception to throw.
   at Rhino.Mocks.Impl.RecordMockState.AssertPreviousMethodIsClose()
   at Rhino.Mocks.Impl.RecordMockState.Replay()
   at Rhino.Mocks.MockRepository.ReplayCore(Object obj, Boolean checkInsideOrdering)
   at Rhino.Mocks.RhinoMocksExtensions.Expect(T mock, Function`2 action)
   at ImageControllerTest.UnitTests.ImageControllerTest.SmokeTest()

The code:

    [TestFixture]
public class ImageControllerTest
{
    [Test]
    public void SmokeTest()
    {
        var container = MockRepository.GenerateStrictMock<IContainer>();
        var imageController = new ImageController(container);

        string imagePhysicalLocation = @"c:\image.jpg";

        Stream imageStream = null;
        container.Expect(x => x.GetImageHandler().LoadImage(imagePhysicalLocation)).Repeat.Once().Return(imageStream);

        container.Expect(x => x.GetImageHandler().ConvertToGrayScale(imageStream)).Repeat.Once().Return(imageStream);

        var dimensions = new KeyValuePair<int, int>(200, 200);

        container.Expect(x => x.GetImageHandler().GetDimensions(imageStream)).Repeat.Once().Return(dimensions);

        imageController.Execute(imagePhysicalLocation);

        container.VerifyAllExpectations();
    }
}

public interface IContainer
{
    IImageHandler GetImageHandler();
}

public interface IImageHandler
{
    Stream LoadImage(string physicalLocation);
    KeyValuePair<int, int> GetDimensions(Stream image);
    Stream ConvertToGrayScale(Stream image);
}

public class ImageController
{
    private readonly IContainer container;

    public ImageController(IContainer container)
    {
        this.container = container;
    }

    public void Execute(string imagePhysicalLocation)
    {
        Stream image = container.GetImageHandler().LoadImage(imagePhysicalLocation);

        Stream imageInGrayScale = container.GetImageHandler().ConvertToGrayScale(image);

        container.GetImageHandler().GetDimensions(imageInGrayScale);
    }
}

Does anyone have any idea how I could solve this error?

Thanks a lot.

Jordy

Upvotes: 0

Views: 1058

Answers (1)

Coleoid
Coleoid

Reputation: 95

You'll need another mock for your ImageHandler, much like this:

[TestFixture]
public class ImageControllerTest
{
    [Test]
    public void SmokeTest()
    {
        var container = MockRepository.GenerateStrictMock<IContainer>();
        var handler = MockRepository.GenerateStrictMock<IImageHandler>();
        var imageController = new ImageController(container);

        string imagePhysicalLocation = @"c:\image.jpg";

        Stream imageStream = null;

        container.Expect(x => x.GetImageHandler()).Return(handler);


        handler.Expect(x => x.LoadImage(imagePhysicalLocation)).Repeat.Once().Return(imageStream);

        handler.Expect(x => x.ConvertToGrayScale(imageStream)).Repeat.Once().Return(imageStream);

        var dimensions = new KeyValuePair<int, int>(200, 200);

        handler.Expect(x => x.GetDimensions(imageStream)).Repeat.Once().Return(dimensions);

        imageController.Execute(imagePhysicalLocation);

        container.VerifyAllExpectations();
        handler.VerifyAllExpectations();
    }
}

public interface IContainer
{
    IImageHandler GetImageHandler();
}

public interface IImageHandler
{
    Stream LoadImage(string physicalLocation);
    KeyValuePair<int, int> GetDimensions(Stream image);
    Stream ConvertToGrayScale(Stream image);
}

public class ImageController
{
    private readonly IContainer container;

    public ImageController(IContainer container)
    {
        this.container = container;
    }

    public void Execute(string imagePhysicalLocation)
    {
        Stream image = container.GetImageHandler().LoadImage(imagePhysicalLocation);

        Stream imageInGrayScale = container.GetImageHandler().ConvertToGrayScale(image);

        container.GetImageHandler().GetDimensions(imageInGrayScale);
    }
}

Good luck!

Upvotes: 1

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