How can I mock the Response.StatusCode with Moq?

Question

I have the following method:

public void SetHttpStatusCode(HttpStatusCode httpStatusCode)
{
    Response.StatusCode = (int)httpStatusCode;
}

And the following test:

[TestMethod]
public void SetHttpStatusCode_SetsCorrectStatusCode()
{
    //Arrange
    //Any url will suffice
    var mockHttpContext = TestHelpers.MakeHttpContext(""); 
    mockHttpContext.SetupSet(x => x.Response.StatusCode = It.IsAny<int>());

    //creates an instance of an asp.net mvc controller
    var controller = new AppController()
    {
        ControllerContext = new ControllerContext() 
        { 
            HttpContext = mockHttpContext.Object 
        }
    };

    // Act
    controller.SetHttpStatusCode(HttpStatusCode.OK);

    //Assert
    mockHttpContext.VerifySet(x => x.Response.StatusCode = It.IsAny<int>());
}

Also, here is MakeHttpContext class

public static Mock<HttpContextBase> MakeHttpContext(string url)
{
    var mockHttpContext = new Mock<HttpContextBase>();
    var mockRequest = new Mock<HttpRequestBase>();
    var mockResponse = new Mock<HttpResponseBase>();
    var mockSession = new Mock<HttpSessionStateBase>();

    //request
    mockRequest.Setup(x => x.AppRelativeCurrentExecutionFilePath).Returns(url);
    mockHttpContext.Setup(x => x.Request).Returns(mockRequest.Object);

    //response
    mockResponse.Setup(x => x.ApplyAppPathModifier(It.IsAny<string>())).Returns<string>(x => x);
    mockHttpContext.Setup(x => x.Response).Returns(mockResponse.Object);

    //session
    mockHttpContext.Setup(x => x.Session).Returns(mockSession.Object);

    return mockHttpContext;
}

When I run the test, I get the following exception:

Test method PA.Tests.Controllers.AppControllerTest.SetHttpStatusCode_SetsCorrectStatusCode
threw exception: 
  

  Moq.MockException: 
    Expected invocation on the mock at least once, 
    but was never performed: x => x.StatusCode = It.IsAny<Int32>()
    
    Configured setups:
    x => x.StatusCode = It.IsAny<Int32>(), Times.Never
    No invocations performed.

How does Moq expect/require invocations to be called? I've debugged the SetHTTPStatusCode method, the response object is indeed a mocked object, however Moq insists that there was no invocation. Am I missing something? tha

Answer 1

You haven't shown what your TestHelpers.MakeHttpContext method does so it's a bit difficult to understand what's going on.

Try like this:

// Arrange
var mockHttpContext = new Mock<HttpContextBase>();
var response = new Mock<HttpResponseBase>();
mockHttpContext.SetupGet(x => x.Response).Returns(response.Object);

//creates an instance of an asp.net mvc controller
var controller = new AppController()
{
    ControllerContext = new ControllerContext() 
    { 
        HttpContext = mockHttpContext.Object 
    }
};

// Act
controller.SetHttpStatusCode(HttpStatusCode.OK);

//Assert
response.VerifySet(x => x.StatusCode = (int)HttpStatusCode.OK);