Application.Current对于单元测试是空的

Question

我在代码库中有一些依赖于Application.Current.Dispatcher.Invoke ...的方法来确保在GUI线程上运行.我目前正在尝试为这些方法编写单元测试但是(正如预期的那样)Application.Current为null所以我得到一个NullReferenceException.

我试图在他们自己的AppDomain中运行受影响的测试,如下所示:http://social.msdn.microsoft.com/Forums/en-US/wpf/thread/786d5c06-0511-41c0-a6a2-5c4e44f8ffb6/

但是当我这样做时,Application.Current仍为null.不应该启动AppDomain为我设置Application.Current？为什么它仍然是空的？

我的代码:基类:

[TestClass()]
[Serializable]
public class UnitTest
{
    protected void ExecuteInSeparateAppDomain(string methodName)
    {
        AppDomainSetup appDomainSetup = new AppDomainSetup();
        appDomainSetup.ApplicationBase = Environment.CurrentDirectory;
        AppDomain appDomain = AppDomain.CreateDomain(methodName, null, appDomainSetup);

        try
        {
            appDomain.UnhandledException += delegate(object sender, UnhandledExceptionEventArgs e)
            {
                throw e.ExceptionObject as Exception;
            };

            UnitTest unitTest = appDomain.CreateInstanceAndUnwrap(GetType().Assembly.GetName().Name, GetType().FullName) as UnitTest;

            MethodInfo methodInfo = unitTest.GetType().GetMethod(methodName, BindingFlags.NonPublic | BindingFlags.Instance);

            if (methodInfo == null)
            {
                throw new InvalidOperationException(string.Format("Method '{0}' not found on type '{1}'.", methodName, unitTest.GetType().FullName));
            }

            try
            {
                methodInfo.Invoke(unitTest, null);
            }
            catch (System.Reflection.TargetInvocationException e)
            {
                throw e.InnerException;
            }
        }
        finally
        {
            AppDomain.Unload(appDomain);
        }
    }
}

调用单元测试(包含在继承自UnitTest的类中):

[TestMethod()]
public void QualifierViewModel_FlagsAndLoadDatasets()
{
    ExecuteInSeparateAppDomain("TestLoadDataSets");
}

Answer 1

所以现在我有一个讨厌的解决方法.我基本上将所有使用Application.Current的测试方法的测试移动到单个测试中(因此它们都将在同一个线程上)并调用新的Application().

令人讨厌的代码:

[TestClass]
    public class IntegrationTests
    {
        private CedarFile testCedarFile;

        /// <summary>
        /// This test tests methods that utilize Application.Current. 
        /// They all have to be in the same test because they must run on the same thread to use the Application instance.
        /// </summary>
        [TestMethod]
        public void IntegrationTests_All()
        {
            new Application();

            QualifierViewModel_FlagsAndLoadDatasets();
            CurrentFilesViewModel_AddCedarFile();
            CurrentFilesViewModel_AddCedarFileReadOnly();
        }
... the private methods to test ...
}

Answer 2

尝试删除该Serializable属性并UnitTest从派生该类MarshalByRefObject。