TaskCancelledException discovering tests

[rynowak]

DTH is throwing every time while trying to load an assembly for test discovery. I hit this consistently with MVC.NoFun.sln and DNX 1.0.0-rc1-15899

Exception: System.AggregateException: One or more errors occurred. ---> System.InvalidOperationException: System.AggregateException: One or more errors occurred. ---> System.Threading.Tasks.TaskCanceledException: A task was canceled.
   --- End of inner exception stack trace ---
   at System.Threading.Tasks.Task.ThrowIfExceptional(Boolean includeTaskCanceledExceptions)
   at System.Threading.Tasks.Task`1.GetResultCore(Boolean waitCompletionNotification)
   at System.Threading.Tasks.Task`1.get_Result()
   at Microsoft.Dnx.Compilation.DesignTime.DesignTimeHostProjectCompiler.CompileProject(CompilationProjectContext projectContext, Func`1 referenceResolver, Func`1 resourcesResolver)
   at Microsoft.Dnx.Compilation.LibraryExporter.<>c__DisplayClass17_0.<ExportProject>b__0(CacheContext ctx)
   at Microsoft.Dnx.Compilation.Caching.CacheExtensions.<>c__DisplayClass0_0`1.<Get>b__0(CacheContext ctx)
   at Microsoft.Dnx.Compilation.Caching.Cache.CreateEntry(Object k, Func`2 acquire)
   at Microsoft.Dnx.Compilation.Caching.Cache.<>c__DisplayClass5_0.<AddEntry>b__0()
   at System.Lazy`1.CreateValue()
   at System.Lazy`1.LazyInitValue()
   at System.Lazy`1.get_Value()
   at Microsoft.Dnx.Compilation.Caching.Cache.Get(Object key, Func`2 factory)
   at Microsoft.Dnx.Compilation.Caching.CacheExtensions.Get[T](ICache cache, Object key, Func`2 factory)
   at Microsoft.Dnx.Compilation.LibraryExporter.ExportProject(ProjectDescription project, String aspect)
   at Microsoft.Dnx.Compilation.LibraryExporter.GetExport(LibraryDescription library, String aspect)
   at Microsoft.Dnx.Compilation.LibraryExporter.GetExport(String name, String aspect)
   at Microsoft.Dnx.Compilation.LibraryExporter.GetExport(String name)
   at Microsoft.Dnx.Runtime.Compilation.RuntimeLibraryExporter.GetExport(String name)
   at Microsoft.Dnx.TestHost.TestServices.CreateTestServices(IServiceProvider applicationServices, Project project, ReportingChannel channel)
   at Microsoft.Dnx.TestHost.Program.<>c__DisplayClass2_0.<<Main>b__0>d.MoveNext()
---> (Inner Exception #0) System.Threading.Tasks.TaskCanceledException: A task was canceled.<---

   --- End of inner exception stack trace ---
   at System.Threading.Tasks.Task.ThrowIfExceptional(Boolean includeTaskCanceledExceptions)
   at System.Threading.Tasks.Task.Wait(Int32 millisecondsTimeout, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.Web.UnitTest.TestAdapter.Discovery.HostExtensions.GetTests(IHost host, ITestCaseDiscoverySink discovery, IMessageLogger logger, KRuntimeConfiguration testConfiguration)
   at Microsoft.VisualStudio.Web.UnitTest.TestAdapter.KUnitTestDiscoverer.GetTestCases(IEnumerable`1 sources, IMessageLogger logger, ITestCaseDiscoverySink discoverySink)
---> (Inner Exception #0) System.InvalidOperationException: System.AggregateException: One or more errors occurred. ---> System.Threading.Tasks.TaskCanceledException: A task was canceled.
   --- End of inner exception stack trace ---
   at System.Threading.Tasks.Task.ThrowIfExceptional(Boolean includeTaskCanceledExceptions)
   at System.Threading.Tasks.Task`1.GetResultCore(Boolean waitCompletionNotification)
   at System.Threading.Tasks.Task`1.get_Result()
   at Microsoft.Dnx.Compilation.DesignTime.DesignTimeHostProjectCompiler.CompileProject(CompilationProjectContext projectContext, Func`1 referenceResolver, Func`1 resourcesResolver)
   at Microsoft.Dnx.Compilation.LibraryExporter.<>c__DisplayClass17_0.<ExportProject>b__0(CacheContext ctx)
   at Microsoft.Dnx.Compilation.Caching.CacheExtensions.<>c__DisplayClass0_0`1.<Get>b__0(CacheContext ctx)
   at Microsoft.Dnx.Compilation.Caching.Cache.CreateEntry(Object k, Func`2 acquire)
   at Microsoft.Dnx.Compilation.Caching.Cache.<>c__DisplayClass5_0.<AddEntry>b__0()
   at System.Lazy`1.CreateValue()
   at System.Lazy`1.LazyInitValue()
   at System.Lazy`1.get_Value()
   at Microsoft.Dnx.Compilation.Caching.Cache.Get(Object key, Func`2 factory)
   at Microsoft.Dnx.Compilation.Caching.CacheExtensions.Get[T](ICache cache, Object key, Func`2 factory)
   at Microsoft.Dnx.Compilation.LibraryExporter.ExportProject(ProjectDescription project, String aspect)
   at Microsoft.Dnx.Compilation.LibraryExporter.GetExport(LibraryDescription library, String aspect)
   at Microsoft.Dnx.Compilation.LibraryExporter.GetExport(String name, String aspect)
   at Microsoft.Dnx.Compilation.LibraryExporter.GetExport(String name)
   at Microsoft.Dnx.Runtime.Compilation.RuntimeLibraryExporter.GetExport(String name)
   at Microsoft.Dnx.TestHost.TestServices.CreateTestServices(IServiceProvider applicationServices, Project project, ReportingChannel channel)
   at Microsoft.Dnx.TestHost.Program.<>c__DisplayClass2_0.<<Main>b__0>d.MoveNext()
---> (Inner Exception #0) System.Threading.Tasks.TaskCanceledException: A task was canceled.<---
<---

========== Discover test finished: 0 found (0:00:01.356003) ==========

[avanderhoorn]

This is blocking debugging from VS :( I'm on dnx 1.0.0-rc1-15904 from the CI feed.

Application startup exception: System.IO.FileLoadException: Could not load file or assembly 'Glimpse.AgentServer.Mvc.Sample' or one of its dependencies. General Exception (Exception from HRESULT: 0x80131500)
File name: 'Glimpse.AgentServer.Mvc.Sample' ---> System.AggregateException: One or more errors occurred. ---> System.Threading.Tasks.TaskCanceledException: A task was canceled.
   --- End of inner exception stack trace ---
   at System.Threading.Tasks.Task.ThrowIfExceptional(Boolean includeTaskCanceledExceptions)
   at System.Threading.Tasks.Task`1.GetResultCore(Boolean waitCompletionNotification)
   at System.Threading.Tasks.Task`1.get_Result()
   at Microsoft.Dnx.Compilation.DesignTime.DesignTimeHostProjectCompiler.CompileProject(CompilationProjectContext projectContext, Func`1 referenceResolver, Func`1 resourcesResolver)
   at Microsoft.Dnx.Compilation.LibraryExporter.<>c__DisplayClass17_0.<ExportProject>b__0(CacheContext ctx)
   at Microsoft.Dnx.Compilation.Caching.CacheExtensions.<>c__DisplayClass0_0`1.<Get>b__0(CacheContext ctx)
   at Microsoft.Dnx.Compilation.Caching.Cache.CreateEntry(Object k, Func`2 acquire)
   at Microsoft.Dnx.Compilation.Caching.Cache.<>c__DisplayClass5_0.<AddEntry>b__0()
   at System.Lazy`1.CreateValue()
   at System.Lazy`1.LazyInitValue()
   at System.Lazy`1.get_Value()
   at Microsoft.Dnx.Compilation.Caching.Cache.Get(Object key, Func`2 factory)
   at Microsoft.Dnx.Compilation.Caching.CacheExtensions.Get[T](ICache cache, Object key, Func`2 factory)
   at Microsoft.Dnx.Compilation.LibraryExporter.ExportProject(ProjectDescription project, String aspect)
   at Microsoft.Dnx.Compilation.LibraryExporter.GetExport(LibraryDescription library, String aspect)
   at Microsoft.Dnx.Compilation.LibraryExporter.GetExport(String name, String aspect)
   at Microsoft.Dnx.Compilation.CompilationEngine.LoadProject(Project project, FrameworkName targetFramework, String aspect, IAssemblyLoadContext loadContext, AssemblyName assemblyName)
   at Microsoft.Dnx.Runtime.Loader.ProjectAssemblyLoader.Load(AssemblyName assemblyName, IAssemblyLoadContext loadContext)
   at Microsoft.Dnx.Runtime.Loader.ProjectAssemblyLoader.Load(AssemblyName assemblyName)
   at Microsoft.Dnx.Host.LoaderContainer.Load(AssemblyName assemblyName)
   at Microsoft.Dnx.Host.DefaultLoadContext.LoadAssembly(AssemblyName assemblyName)
   at Microsoft.Dnx.Runtime.Loader.AssemblyLoaderCache.GetOrAdd(AssemblyName name, Func`2 factory)
   at Microsoft.Dnx.Runtime.Loader.LoadContext.LoadAssemblyImpl(AssemblyName assemblyName)
   at Microsoft.Dnx.Runtime.Loader.LoadContext.ResolveAssembly(Object sender, ResolveEventArgs args)
   at System.AppDomain.OnAssemblyResolveEvent(RuntimeAssembly assembly, String assemblyFullName)
---> (Inner Exception #0) System.Threading.Tasks.TaskCanceledException: A task was canceled.<---

   at System.Reflection.RuntimeAssembly._nLoad(AssemblyName fileName, String codeBase, Evidence assemblySecurity, RuntimeAssembly locationHint, StackCrawlMark& stackMark, IntPtr pPrivHostBinder, Boolean throwOnFileNotFound, Boolean forIntrospection, Boolean suppressSecurityChecks)
   at System.Reflection.RuntimeAssembly.nLoad(AssemblyName fileName, String codeBase, Evidence assemblySecurity, RuntimeAssembly locationHint, StackCrawlMark& stackMark, IntPtr pPrivHostBinder, Boolean throwOnFileNotFound, Boolean forIntrospection, Boolean suppressSecurityChecks)
   at System.Reflection.RuntimeAssembly.InternalLoadAssemblyName(AssemblyName assemblyRef, Evidence assemblySecurity, RuntimeAssembly reqAssembly, StackCrawlMark& stackMark, IntPtr pPrivHostBinder, Boolean throwOnFileNotFound, Boolean forIntrospection, Boolean suppressSecurityChecks)
   at System.Reflection.Assembly.Load(AssemblyName assemblyRef)
   at Microsoft.AspNet.Hosting.Startup.StartupLoader.FindStartupType(String startupAssemblyName, IList`1 diagnosticMessages)
   at Microsoft.AspNet.Hosting.Internal.HostingEngine.EnsureStartup()
   at Microsoft.AspNet.Hosting.Internal.HostingEngine.EnsureApplicationServices()
   at Microsoft.AspNet.Hosting.Internal.HostingEngine.BuildApplication()


Hosting environment: Production
Now listening on: http://localhost:5000
Application started. Press Ctrl+C to shut down.

[muratg]

Troy will be investigating this today.

[troydai]

Found the problem. I'm going to submit a PR soon in which I'll explain the cause.

[mrahhal]

Finally 👍