private static void SetElementDataContext(bool upperBoundExceeded)
{
BoundedCounter counter = new BoundedCounter(1);
counter.TryIncrement();
if (upperBoundExceeded) // if true, we're 1 over capacity. if false, we're exactly at capacity
{
counter.TryIncrement();
}
ShimElementDataContext dc = new ShimElementDataContext
{
ElementCounterGet = () => counter
};
ShimGetDataAction.GetElementDataContextGuid = (_) => dc;
}
/// <summary>
/// Populate tree by retrieving all children at once.
/// </summary>
/// <param name="rootNode"></param>
/// <param name="parentNode"></param>
/// <param name="startChildId"></param>
private int PopulateChildrenTreeNode(A11yElement rootNode, A11yElement parentNode, int startChildId)
{
this.Elements.Add(rootNode);
rootNode.Parent = parentNode;
rootNode.TreeWalkerMode = this.WalkerMode; // set tree walker mode.
IUIAutomationTreeWalker walker = A11yAutomation.GetTreeWalker(this.WalkerMode);
IUIAutomationElement child = (IUIAutomationElement)rootNode.PlatformObject;
if (child != null)
{
try
{
child = walker.GetFirstChildElement(child);
}
#pragma warning disable CA1031 // Do not catch general exception types
catch (Exception ex)
{
ex.ReportException();
child = null;
System.Diagnostics.Trace.WriteLine("Tree walker exception: " + ex);
}
#pragma warning restore CA1031 // Do not catch general exception types
while (child != null && _elementCounter.TryIncrement())
{
#pragma warning disable CA2000 // childNode will be disposed by the parent node
// Create child without populating basic property. it will be set all at once in parallel.
var childNode = new DesktopElement(child, true, false);
#pragma warning restore CA2000 // childNode will be disposed by the parent node
rootNode.Children.Add(childNode);
childNode.Parent = rootNode;
childNode.UniqueId = startChildId++;
startChildId = PopulateChildrenTreeNode(childNode, rootNode, startChildId);
try
{
child = walker.GetNextSiblingElement(child);
}
#pragma warning disable CA1031 // Do not catch general exception types
catch (Exception ex)
{
ex.ReportException();
child = null;
System.Diagnostics.Trace.WriteLine("Tree walker exception: " + ex);
}
#pragma warning restore CA1031 // Do not catch general exception types
}
}
Marshal.ReleaseComObject(walker);
return(startChildId);
}
public void Reset_UpperBoundExceeded_SetsCorrectValues()
{
const int upperBound = 1;
BoundedCounter counter = new BoundedCounter(upperBound);
counter.TryIncrement();
counter.Reset();
Assert.AreEqual(0, counter.Attempts);
Assert.AreEqual(0, counter.Count);
Assert.AreEqual(upperBound, counter.UpperBound);
Assert.IsFalse(counter.UpperBoundExceeded);
}
public void TryIncrement_Overflows_ReturnsFalse_Updates_State()
{
const int upperBound = int.MaxValue - 1;
BoundedCounter counter = new BoundedCounter(upperBound);
Assert.IsTrue(counter.TryAdd(upperBound));
for (int loop = 0; loop < 5; loop++)
{
Assert.IsFalse(counter.TryIncrement());
Assert.AreEqual(int.MaxValue, counter.Attempts);
Assert.AreEqual(upperBound, counter.Count);
}
}
public void TryIncrement_UpperBoundNotExceeded_ReturnsTrue_UpdatesState()
{
const int upperBound = 5;
BoundedCounter counter = new BoundedCounter(upperBound);
for (int loop = 0; loop < upperBound; loop++)
{
Assert.AreEqual(upperBound, counter.UpperBound);
Assert.AreEqual(loop, counter.Attempts);
Assert.AreEqual(loop, counter.Count);
Assert.IsFalse(counter.UpperBoundExceeded);
Assert.IsTrue(counter.TryIncrement());
}
Assert.IsFalse(counter.UpperBoundExceeded);
}
/// <summary>
/// Add element and children into the list.
/// </summary>
/// <param name="e"></param>
/// <param name="dic"></param>
/// <param name="elementCounter">Provides an upper bound on the number of elements we'll allow to be loaded</param>
internal static void AddElementAndChildrenIntoList(A11yElement e, Dictionary <int, A11yElement> dic, BoundedCounter elementCounter)
{
if (!elementCounter.TryIncrement())
{
return;
}
dic.Add(e.UniqueId, e);
if (e.Children != null && e.Children.Count != 0)
{
foreach (var c in e.Children)
{
AddElementAndChildrenIntoList(c, dic, elementCounter);
}
}
}
public void TryIncrement_UpperBoundExceeded_ReturnsFalse_UpdatesState()
{
const int upperBound = 5;
BoundedCounter counter = new BoundedCounter(upperBound);
Assert.IsTrue(counter.TryAdd(upperBound));
Assert.IsFalse(counter.UpperBoundExceeded);
// UpperBound has been reached, so all further adds should fail
for (int loop = 0; loop < upperBound; loop++)
{
Assert.AreEqual(upperBound, counter.UpperBound);
Assert.AreEqual(upperBound, counter.Count);
Assert.AreEqual(upperBound + loop, counter.Attempts);
Assert.IsFalse(counter.TryIncrement());
Assert.IsTrue(counter.UpperBoundExceeded);
}
}