Async unit tests in C++/Cx

WaitForTask.h

template <typename T>
T WaitForTask(concurrency::task<T> t)
{
    Windows::UI::Core::CoreDispatcher^ dispatcher =
        Windows::ApplicationModel::Core::CoreApplication::MainView->CoreWindow->Dispatcher;

    HANDLE hEvent = CreateEventEx(NULL, NULL, CREATE_EVENT_MANUAL_RESET, EVENT_ALL_ACCESS);
    if (hEvent == NULL)
        throw std::bad_alloc();

    T result;
    bool exceptionHandled = false;
    std::wstring exceptionMessage;
    t.then([&hEvent, &exceptionHandled, &exceptionMessage, &result](concurrency::task<T> previousTask){
        try
        {
            result = previousTask.get();
        } 
        catch (Platform::Exception^ ex)
        {
            exceptionHandled = true;
            exceptionMessage = std::wstring(ex->Message->Data());
        }
        catch (std::exception & ex)
        {
            exceptionHandled = true;
            exceptionMessage = std::wstring(ex.what(), ex.what() + strlen(ex.what()));
        }
        catch (...)
        {
            exceptionHandled = true;
            exceptionMessage = std::wstring(L"Unrecognized C++ exception.");
        }
        SetEvent(hEvent);
    }, concurrency::task_continuation_context::use_arbitrary());

    DWORD waitResult = STATUS_PENDING;
    while (waitResult != WAIT_OBJECT_0)
    {
        dispatcher->ProcessEvents(Windows::UI::Core::CoreProcessEventsOption::ProcessAllIfPresent);
        waitResult = WaitForSingleObjectEx(hEvent, 0, TRUE);
    }

    CloseHandle(hEvent);

    if (exceptionHandled)
        Microsoft::VisualStudio::CppUnitTestFramework::Assert::Fail(exceptionMessage.c_str());

    return result;
}

template<>
inline void WaitForTask<void>(concurrency::task<void> t)
{
    WaitForTask(t.then([]{ return true; }));
}

template <typename T>
inline T WaitForTask(Windows::Foundation::IAsyncOperation<T>^ t)
{
    return WaitForTask(concurrency::task<T>(t));
}

inline void WaitForTask(Windows::Foundation::IAsyncAction^ t)
{
    return WaitForTask(concurrency::task<void>(t));
}