public bool AugmentSignatureHelpSession(ISignatureHelpSession session, IList <ISignature> signatures, AstRoot ast, Action <object, string> triggerSession, string packageName)
{
ITextSnapshot snapshot = _textBuffer.CurrentSnapshot;
int position = session.GetTriggerPoint(_textBuffer).GetPosition(snapshot);
// Retrieve parameter positions from the current text buffer snapshot
ParameterInfo parametersInfo = SignatureHelp.GetParametersInfoFromBuffer(ast, snapshot, position);
if (parametersInfo != null)
{
position = Math.Min(parametersInfo.SignatureEnd, position);
int start = Math.Min(position, snapshot.Length);
int end = Math.Min(parametersInfo.SignatureEnd, snapshot.Length);
ITrackingSpan applicableToSpan = snapshot.CreateTrackingSpan(Span.FromBounds(start, end), SpanTrackingMode.EdgeInclusive);
IFunctionInfo functionInfo = null;
// First try user-defined function
if (string.IsNullOrEmpty(parametersInfo.PackageName))
{
functionInfo = ast.GetUserFunctionInfo(parametersInfo.FunctionName, position);
}
else
{
packageName = parametersInfo.PackageName;
}
if (functionInfo == null)
{
var functionIndex = _shell.ExportProvider.GetExportedValue <IFunctionIndex>();
// Then try package functions
packageName = packageName ?? _packageName;
_packageName = null;
// Get collection of function signatures from documentation (parsed RD file)
functionInfo = functionIndex.GetFunctionInfo(parametersInfo.FunctionName, packageName, triggerSession, session);
}
if (functionInfo != null && functionInfo.Signatures != null)
{
foreach (ISignatureInfo signatureInfo in functionInfo.Signatures)
{
ISignature signature = CreateSignature(session, parametersInfo.FunctionName, functionInfo, signatureInfo, applicableToSpan, ast, position);
signatures.Add(signature);
}
session.Properties["functionInfo"] = functionInfo;
return(true);
}
}
return(false);
}