Goto Symbol with custom ChooseByNameContributor shows no results for some name, but just spins without error in Console

I'm writing a ChooseByNameContributor to act as the GotoSymbolContributor for my Elixir plugin.  It works well, but for some inputs that I know have matches, the spinner just keeps spinning without finding the match, but there is also no error reported in the console.  I can set break points and see that the match is being made, but I never see the match in the UI.  The odd thing is that I can get matches for shorter prefixes like "me" works, but "message" fails and "ex" works, but "exception" fails.  Is there some way to debug or log why it's failing?