Enable Code Lens / Inlay-Hints in neovim?

[rabiescow]

Hello,

I can't find any documentation nor information on how to enable code-lens or inlay-hints with ocaml-lsp for neovim. I understand that the ocaml-lsp has those features from testing it in VSCode (I have a recollection of them being there in the past as well, so I assume the default values were changed at some point?). The feature I especially want is the inlay-hints of the type definition of functions.

The lsp specific settings at the bottom of my ocamllsp config doesn't seem to have any effect. What is the correct way to communicate with the lsp here?

This is my language server setup:

    lsp.ocamllsp.setup({
      capabilities = capabilities,
      on_attach = on_attach,
      cmd = { "ocamllsp" },
      filetypes = {
        "ocaml",
        "ocaml.menhir",
        "ocaml.interface",
        "ocaml.ocamllex",
        "dune"
      },
      root_dir = lsp.util.root_pattern(
        "*.opam",
        "esy.json",
        "package.json",
        ".git",
        "dune-project",
        "dune-workspace"
      ),
      -- grabbed from https://github.com/ocaml/ocaml-lsp/blob/3dc1a6633bfe2ebd34d7aa38f008c8c28300ee55/ocaml-lsp-server/docs/ocamllsp/config.md
      -- these settings don't seem to have any effect.
      settings = {
        ocamllsp = { 
          extendedHover = true,
          codelens = true,
          duneDiagnostics = true,
          inlayHints = true,
          syntaxDocumentation = true,
          merlinJumpCodeActions = true,
        },
      },
    })

My config for the inlay hints and code lensing (works for golang and lua):

-- Inlay Hint provider config
-- Only turn on inlay hints when not in Insert mode
if client.server_capabilities.inlayHintProvider then
  local inlayhint = vim.api.nvim_create_augroup(
    "LspInlayHint", { clear = true })
  vim.api.nvim_create_autocmd({ "InsertLeave", "BufEnter" }, {
    buffer = bufnr,
    group = inlayhint,
    callback = function()
      vim.g.inlay_hints_visible = true
      vim.lsp.inlay_hint.enable(true, { bufnr })
    end
  })
  vim.api.nvim_create_autocmd({ "InsertEnter" }, {
    buffer = bufnr,
    group = inlayhint,
    callback = function()
      vim.g.inlay_hints_visible = false
      vim.lsp.inlay_hint.enable(false, { bufnr })
    end
    })
  else
    print("no inlay_hints available")
  end

-- Code Lens provider config
-- Only turn on code lens when not in Insert mode
if client.server_capabilities.codeLensProvider then
  local codelens = vim.api.nvim_create_augroup(
    "LSPCodeLens", { clear = true })
  vim.api.nvim_create_autocmd({ "InsertLeave", "BufEnter" }, {
    buffer = bufnr,
    group = codelens,
    callback = function()
      vim.lsp.codelens.refresh()
      local lenses = vim.lsp.codelens.get(bufnr)
      vim.lsp.codelens.display(lenses, bufnr, client.id)
    end,
  })
  vim.api.nvim_create_autocmd({ "InsertEnter" }, {
    buffer = bufnr,
    group = codelens,
    callback = function()
      vim.lsp.codelens.clear(client.id, bufnr)
    end,
  })
end

[rabiescow]

I was finally able to get it working.

settings = {
  extendedHover = { enable = true },
  codelens = { enable = true },
  duneDiagnostics = { enable = true },
  inlayHints = { enable = true },
  syntaxDocumentation = { enable = true },
  merlinJumpCodeActions = { enable = true },
},

I removed the ocamllsp level.

Most other LSP have their settings one level down from settings like lua will need something like this:

settings = {
    Lua = {
        completion = {
             enable = true,
             callSnippet = "replace,
        },
        hint = {
             enable = true,
        } ...

I just wanted to leave this here in case anyone else runs in to the same issue and are having a hard time finding the solution to turn on inlay hints and other lsp specific settings from the ocamllsp.

[voodoos]

Thanks @rabiescow we do have plans to improve support for neovim in the near future! I will keep that issue open until we do. cc @Julow