/// <summary>
/// Tries to find the node with the smallest width in the <paramref name="sourceFile"/>
/// that contains the input <paramref name="position"/>, and is deemed acceptable by
/// <paramref name="isNodeAcceptable"/>.
/// If the position points to a comment, the resulting node is null.
/// </summary>
public static bool TryGetNodeAtPosition(ISourceFile sourceFile, int position, Func <INode, bool> isNodeAcceptable, System.Threading.CancellationToken token, out INode currentNode)
{
Contract.Requires(sourceFile != null);
Contract.Requires(position >= 0);
INode result = null;
NodeWalker.TraverseDepthFirstAndSelfInOrder(
sourceFile,
node =>
{
var startPosition = node.GetNodeStartPositionWithoutTrivia(sourceFile);
if (result != null && startPosition > position)
{
// We can stop the traversal already because the next node starts after the expected position.
// And we know that the traversal is depth first from left to right.
return(false);
}
if (startPosition <= position && position <= node.End)
{
if (result == null || node.GetNodeWidth(sourceFile) <= result.GetNodeWidth(sourceFile))
{
if (isNodeAcceptable(node))
{
result = node;
}
}
}
return(true);
},
token);
currentNode = result;
return(result != null);
}