public static async Task <SyntaxTreeIdentifierInfo> GetIdentifierInfoAsync(Document document, CancellationToken cancellationToken)
{
SyntaxTreeIdentifierInfo info;
if (identifierSnapshotCache.TryGetValue(document, out info))
{
return(info);
}
info = await SyntaxTreeIdentifierInfo.LoadAsync(document, cancellationToken).ConfigureAwait(false);
if (info != null)
{
return(identifierSnapshotCache.GetValue(document, _ => info));
}
// alright, we don't have cached information, re-calcuate them here.
var data = await CreateInfoAsync(document, cancellationToken).ConfigureAwait(false);
// okay, persist this info.
await data.Item1.SaveAsync(document, cancellationToken).ConfigureAwait(false);
await data.Item2.SaveAsync(document, cancellationToken).ConfigureAwait(false);
info = data.Item1;
return(identifierSnapshotCache.GetValue(document, _ => info));
}