如何使用moq模擬ControllerContext？ ERROR而嘲笑ControllerContext

Question

我使用的MOQ框架和我有以下單元測試並且它與下面的錯誤消息「對象引用不設置爲一個對象的一個​​實例，」未能在下面的代碼行

viewCxt.View.Render(viewCxt, writer); 

任何人都可以指出我正確的方向，請問爲什麼這不通過測試？

[Test] 
public void can_call_PopulateBankTransactionWorkQueueViewInTransactionMetaDataAjaxResponseObject() 
{ 

    var transactionMetaData = new TransactionMetaDataDTO() { TransactionId = "1", FileId = "1", LockboxNumber = "0402020", DepositDate = "04.26.2011", BatchId = "1" }; 


    var request = new Mock<HttpRequestBase>(); 
    request.Setup(r => r.HttpMethod).Returns("GET"); 
    var mockHttpContext = new Mock<HttpContextBase>(); 
    mockHttpContext.Setup(c => c.Request).Returns(request.Object); 

    var controllerContext = new ControllerContext(mockHttpContext.Object, new Mock<RouteData>().Object, new Mock<ControllerBase>().Object); 

    var checkWorkQueueController = new CheckWorkQueueController(
      activeDirectorySecurityManager.Object, businessObjectAdapter, httpRequestObjectHelper.Object, invoiceRepos.Object, new HtmlHelpers()); 

    checkWorkQueueController.ControllerContext = controllerContext; 
    Assert.DoesNotThrow(() => checkWorkQueueController.PopulateBatchTreeSelectorViewInTransactionMetaDataAjaxResponseObject(transactionMetaData)); 
} 

internal void PopulateBatchTreeSelectorViewInTransactionMetaDataAjaxResponseObject(TransactionMetaDataDTO transactionMetaDataDTO) 
{ 

    var checkWorkQueueViewModel = new CheckWorkQueueViewModel(securityManager, businessObjectAdapter); 
    SetActiveFileAndLockbox(transactionMetaDataDTO, checkWorkQueueViewModel, transactionMetaDataDTO.FileId, transactionMetaDataDTO.LockboxNumber); 
    transactionMetaDataDTO.BatchTreeSelectorView = htmlHelpers.RenderViewToString(ApplicationConstants.CheckWorkQueueViewPath + ApplicationConstants.BatchTreeSelectorViewFileName, this, checkWorkQueueViewModel); 
} 

public string RenderViewToString<T>(string viewPath, ControllerBase controller, T model) 
{ 
     controller.ViewData.Model = model; 
     using (var writer = new StringWriter()) 
     { 
      var view = new WebFormView(viewPath); 
      var vdd = new ViewDataDictionary<T>(model); 
      var viewCxt = new ViewContext(controller.ControllerContext, view, vdd, new TempDataDictionary(), writer); 
      viewCxt.View.Render(viewCxt, writer); //ERROR throwing here 
      return writer.ToString(); 
     } 
} 

這裏是堆棧跟蹤：

at System.Web.VirtualPath.GetCacheKey() 
at System.Web.Compilation.BuildManager.GetCacheKeyFromVirtualPath(VirtualPath virtualPath, Boolean& keyFromVPP) 
at System.Web.Compilation.BuildManager.GetVPathBuildResultFromCacheInternal(VirtualPath virtualPath, Boolean ensureIsUpToDate) 
at System.Web.Compilation.BuildManager.GetVPathBuildResultInternal(VirtualPath virtualPath, Boolean noBuild, Boolean allowCrossApp, Boolean allowBuildInPrecompile, Boolean throwIfNotFound, Boolean ensureIsUpToDate) 
at System.Web.Compilation.BuildManager.GetVPathBuildResultWithNoAssert(HttpContext context, VirtualPath virtualPath, Boolean noBuild, Boolean allowCrossApp, Boolean allowBuildInPrecompile, Boolean throwIfNotFound, Boolean ensureIsUpToDate) 
at System.Web.Compilation.BuildManager.GetVirtualPathObjectFactory(VirtualPath virtualPath, HttpContext context, Boolean allowCrossApp, Boolean throwIfNotFound) 
at System.Web.Compilation.BuildManager.GetVirtualPathObjectFactory(VirtualPath virtualPath, HttpContext context, Boolean allowCrossApp) 
at System.Web.Compilation.BuildManager.CreateInstanceFromVirtualPath(VirtualPath virtualPath, Type requiredBaseType, HttpContext context, Boolean allowCrossApp) 
at System.Web.Compilation.BuildManager.CreateInstanceFromVirtualPath(String virtualPath, Type requiredBaseType) 
at System.Web.Mvc.BuildManagerWrapper.System.Web.Mvc.IBuildManager.CreateInstanceFromVirtualPath(String virtualPath, Type requiredBaseType) 
at System.Web.Mvc.WebFormView.Render(ViewContext viewContext, TextWriter writer) 

Answer 1

一個很好的方式來調試究竟需要是對模擬設置是與MockBehavior.Strict選項來創建它。所以，

var mockHttpContext = new Mock<HttpContextBase>(); 

成爲

var mockHttpContext = new Mock<HttpContextBase>(MockBehavior.Strict); 

然後，當需要從您沒有設置背景下的一些測試將失敗，MockException。稍後可以恢復爲鬆散選項。