Cannot Open Files in WinRT Unit Testing - serialization

Question

I am writing a unit test to validate the serialization of objects and I am able to successfully save the file without any issue. I can even browse the file and validate the contents are correct. However, when I attempt to open the file for reading I always receive an UnauthorizedAccess exception.
Here is the code used to save the item:
public static async Task SaveItem<T>(string folderName, T item)
where T : BaseBusinessItem
{
if (string.IsNullOrEmpty(folderName))
{
throw new ArgumentNullException("folderName");
}
if (item == null)
{
throw new ArgumentNullException("item");
}
try
{
var folder = await ApplicationData.Current.LocalFolder
.CreateFolderAsync(folderName, CreationCollisionOption.OpenIfExists);
var file =
await
folder.CreateFileAsync(item.UniqueID.GetHashCode().ToString(), CreationCollisionOption.ReplaceExisting);
var stream = await file.OpenAsync(FileAccessMode.ReadWrite);
using (var outStream = stream.GetOutputStreamAt(0))
{
var serializer = new DataContractJsonSerializer(typeof(T));
serializer.WriteObject(outStream.AsStreamForWrite(), item);
await outStream.FlushAsync();
}
}
catch (Exception ex)
{
Debug.WriteLine(ex.ToString());
}
}
Here is the code used to restore the item:
public static async Task<T> RestoreItem<T>(string folderName, string hashCode)
where T : BaseBusinessItem, new()
{
if (string.IsNullOrEmpty(folderName))
{
throw new ArgumentNullException("folderName");
}
if (string.IsNullOrEmpty(hashCode))
{
throw new ArgumentNullException("hashCode");
}
var folder = await ApplicationData.Current.LocalFolder.GetFolderAsync(folderName);
var file = await folder.GetFileAsync(hashCode);
var inStream = await file.OpenSequentialReadAsync();
var serializer = new DataContractJsonSerializer(typeof(T));
var retVal = (T)serializer.ReadObject(inStream.AsStreamForRead());
return retVal;
}
And the unit test:
[TestMethod]
public async Task TestFileSaveLoad()
{
await _ds.SaveItem("TestFolder");
Guid ID = _item.UniqueID;
_ds = await ItemDataSource.LoadItem("TestFolder", ID.GetHashCode().ToString());
}
Any ideas or troubleshooting steps I might be missing. The unit test app manifest includes the following capabilities: Document Library, Internet (Client). The following declarations are in place: File Open Picker, File Save Picker and File Type Associations.
Thanks!

Answer 1

This code snippet helped me accomplish my goal. Hope this is helpful for someone else:
http://codepaste.net/gtu5mq