public void FindVisualDescendantTest()
{
UITester.Dispatcher.Invoke(() =>
{
var dummy = WPFHelper.FindVisualDescendant <Button>(null);
Assert.IsNull(dummy);
var treeViewItem = testTreeView.FindVisualDescendant <TreeViewItem>();
Assert.IsNotNull(treeViewItem);
Assert.IsInstanceOfType(treeViewItem, typeof(TreeViewItem));
});
}