Cannot manage to trigger completion on ,<space> or $

Hello, first, many thanks for implementing language server in R it works great and out of the box !

I use languageserver in vim via coc-r-lsp and in combination with nvim-r. Completion works fine when triggered by ( or , but I tried to setup completion after ,<space> with no success.

I asked a question here and I understand that completion should be provided by the server.

As per documentation, I added the following to my .Rprofile

options(languageserver.server_capabilities = list(                                                 
        signatureHelpProvider = list(triggerCharacters = list("(", ",", "$"))),                    
        completionProvider = list(resolveProvider = TRUE, triggerCharacters = list(".", ":", "$")) 
)                                                                                                  

But I cannot get any completion after ,<space>, would you have some pointers for me ?

PS: please not that I tried to get completion of data.frame columns too and could not get it to complete either

Start by reproducing completion in Vim with coc-r-lsp and nvim-r, using the .Rprofile server_capabilities configuration shown in the issue. Check behavior after comma-space and for data.frame columns, then compare it with completion triggered by (, comma, or $. Done means the reported completion cases work through the R language server.