It is a well known problem with Resharper that it does dot deal with generated .g.cs or .g.vb files other than those of a few of Microsoft tools such as XAML. The reason is that Resharper does not use MsBuild to resolve the content to compile. As this is the case, there must be an alternative process of doing this.
As a tool vendor, how can I write a Resharper plugin to recognise our Custom Tasks. Please, prove me wrong when I'm feeling that ReSharper Intellisense has a We-Only-Allow-Tools-Written-By-Microsoft policy. The suggestion to ask the developers to include the obj/.../*.g.cs or obj/.../*.g.vb files in their projects as has been suggested by JetBrains over the years is seriously flawed and causes all kinds of problems and support.