/// <summary>
/// Tries to find a completion handler given for the current AST node.
/// </summary>
/// <remarks>
/// Note that in order for this function to work correctly, the <see cref="m_completionInformation"/> list must
/// remain sorted by "starting syntax kind" and then by the "longest" parent kind list as
/// the longest chains are checked first, then smaller chains, and so on, to find the best
/// handler for the job.
/// </remarks>
private bool TryFindCompletionHandlerForNode(CompletionState completionState, out SymbolCompletionHandler symbolHandler, out CompletionItemCompletionHandler completionHandler, out INode completionNode)
{
symbolHandler = null;
completionHandler = null;
completionNode = null;
foreach (var completionInfo in m_completionInformation)
{
if (completionInfo.StartingSyntaxKind == completionState.StartingNode.Kind)
{
symbolHandler = completionInfo.SymbolCompletionHandler;
completionHandler = completionInfo.CompletionItemCompletionHandler;
completionNode = completionState.StartingNode;
// If we don't have any parent kinds, then we are done.
if (completionInfo.ParentKinds.IsNullOrEmpty())
{
return(true);
}
// Walk up the parent kinds and make sure that our node has
// the correct type of parent.
foreach (var parentKind in completionInfo.ParentKinds)
{
completionNode = (completionNode.Parent?.Kind == parentKind) ? completionNode.Parent : null;
if (completionNode == null)
{
break;
}
}
// If at this point, we still have a completion node, then we are good to go as we have matched
// the longest parent kind list.
if (completionNode != null)
{
if (completionInfo.ShouldRunHandler == null || completionInfo.ShouldRunHandler(completionState, completionNode))
{
return(true);
}
}
}
}
return(false);
}
/// <nodoc/>
private void AddSymbolCompletionHandlerInformation(SyntaxKind startingSyntaxKind, SymbolCompletionHandler completionHandler, params SyntaxKind[] parentKinds)
{
m_completionInformation.Add(new CompletionInformation
{
StartingSyntaxKind = startingSyntaxKind,
ParentKinds = parentKinds.ToList(),
SymbolCompletionHandler = completionHandler,
ShouldRunHandler = (state, node) => true,
});
}
