public async Task <SignatureHelp> GetSignatureHelp(int position)
{
var document = this.host.GetDocument(this.documentId);
var signature = new SignatureHelp();
var invocation = await GetInvocation(document, position).ConfigureAwait(false);
if (invocation == null)
{
return(null);
}
var methods = GetMethodOverloads(invocation.SemanticModel, invocation.Node);
if (methods == null)
{
return(null);
}
foreach (var comma in invocation.ArgumentList.Arguments.GetSeparators())
{
if (comma.Span.Start > invocation.Position)
{
break;
}
signature.ActiveParameter += 1;
}
var signatureHelpItemList = new List <SignatureHelpItem>();
var bestScore = int.MinValue;
SignatureHelpItem bestScoredItem = null;
var types = invocation.ArgumentList.Arguments
.Select(argument => invocation.SemanticModel.GetTypeInfo(argument.Expression));
foreach (var method in methods)
{
var buildItem = BuildItem(method, invocation.SemanticModel, position);
signatureHelpItemList.Add(buildItem);
var score = InvocationScore(method, types);
if (score <= bestScore)
{
continue;
}
bestScore = score;
bestScoredItem = buildItem;
}
if (bestScoredItem == null)
{
return(null);
}
signature.ActiveSignature = signatureHelpItemList.IndexOf(bestScoredItem);
signature.SignatureHelpItems = signatureHelpItemList;
return(signature);
}
public OverloadProvider(SignatureHelp signature)
{
this.signature = signature;
if (signature.ActiveSignature > 0)
{
this.selectedIndex = signature.ActiveSignature;
}
this.BuildContent();
}
