randomness in nvim-cmp functionality

[aggonis]

hello 👋 i've just started trying to integrate the mighty LSP features in my nvim setup, and so far i've been trying to replicate some advice found either thru chatgpt or online... then i discovered your blog posts which do a wonderful job at trying to get people started with as little as possible.

to start with, i tried structuring my existing setup LSP (lazy, mason, mason-lspconfig, lspconfig, nvim-cmp, and cmp-nvim-lsp) to your Getting Started/Plot Twist config, and whilst everything works as you'd expect (specifically for my python setup - basedpyright and ruff), there are instances when i start nvim and the autocompletion will simply not work... not even by triggering the keybinding for it to show up. i tried setting the dependencies "correctly" in my plugin lua configs, but then again, there's still that random element as to whether the autocompletion will start when i start a new instance of nvim.

so far my configs are split into individual plugin.lua documents:
mason.lua:

return {
  'williamboman/mason.nvim',
  opts = {},
}

mason-lspconfig.lua:

return {
  'williamboman/mason-lspconfig.nvim',
  dependencies = {
    'williamboman/mason.nvim',
  },
  opts = {
    ensure_installed = { 'basedpyright', 'ruff' }, -- Ensure these LSPs are installed
    automatic_installation = true, -- Automatically install missing LSPs on startup
  },
}

nvim-lspconfig.lua:

return {
  'neovim/nvim-lspconfig',
  dependencies = {
    'williamboman/mason-lspconfig.nvim',
    'hrsh7th/cmp-nvim-lsp',
    -- 'VonHeikemen/lsp-zero.nvim',
  },
  config = function()
    -- local capabilities = require('cmp_nvim_lsp').default_capabilities()
    local lspconfig = require('lspconfig')

    lspconfig.util.default_config.capabilities = vim.tbl_deep_extend(
      'force',
      lspconfig.util.default_config.capabilities,
      require('cmp_nvim_lsp').default_capabilities()
    )

    lspconfig.basedpyright.setup {
      -- capabilities = capabilities,

      on_attach = function(client, bufnr)
        if client.server_capabilities.inlayHintProvider then
          vim.lsp.inlay_hint.enable(true, { bufnr = bufnr })
        end
      end,

      settings = {
        basedpyright = {
          disableOrganizeImports = true,

          analysis = {
            diagnosticMode = "workspace",
            typeCheckingMode = "off",
            logLevel = "Trace",
              -- useLibraryCodeForTypes = false,
          },
        },
        python = {
          pythonPath = "/opt/homebrew/Caskroom/miniconda/base/envs/<my_env_name>/bin/python",
        },
      }
    }

    require('lspconfig').ruff.setup({})
    --   capabilities = capabilities,
    -- })
  end,
}

nvim-cmp.lua:

return {
  'hrsh7th/nvim-cmp',
  dependencies = {
    'hrsh7th/cmp-nvim-lsp', -- LSP completions
    -- 'hrsh7th/cmp-nvim-lsp-signature-help', -- LSP Signature help
    -- 'hrsh7th/cmp-buffer', -- Buffer completions
    -- 'hrsh7th/cmp-path', -- File path completions
  },
  config = function()
    local cmp = require('cmp')
    -- local cmp_action = require('lsp_zero')

    cmp.setup({
      sources = cmp.config.sources({
        { name = 'nvim_lsp' },
        -- { name = 'nvim_lsp_signature_help' },
        -- { name = 'buffer' },
        -- { name = 'path' },
      }),
      snippet = {
        expand = function(args)
          vim.snippet.expand(args.body)
        end,
      },
      mapping = cmp.mapping.preset.insert({
        -- `Enter` key to confirm completion
        ['<CR>'] = cmp.mapping.confirm({select = false}),

        -- Ctrl+Space to trigger completion menu
        ['<C-Space>'] = cmp.mapping.complete(),

        -- Navigate between snippet placeholder
        -- ['<C-f>'] = cmp_action.vim_snippet_jump_forward(),
        -- ['<C-b>'] = cmp_action.vim_snippet_jump_backward(),

        -- Scroll up and down in the completion documentation
        ['<C-u>'] = cmp.mapping.scroll_docs(-4),
        ['<C-d>'] = cmp.mapping.scroll_docs(4),
      }),
    })
  end
}

and finally, cmp-nvim-lsp.lua:

return {
  'hrsh7th/cmp-nvim-lsp',
  config = function()
    require('cmp').setup({
      sources = {
        name = 'nvim_lsp',
      }
    })
  end,
}

i tried looking thru the lazy profiling tab for instances where the autocompletion works and doesn't, but i cannot find an exact pattern that would lead to either scenario (e.g. i tried checking whether the ordering of the plugins has an effect, albeit based on the dependencies attributes that should always be in the same order), and in both cases, the output i get from basedpyright for the completion support is:

  completionProvider = {
    completionItem = {
      labelDetailsSupport = true
    },
    resolveProvider = true,
    triggerCharacters = { ".", "[", '"', "'" },
    workDoneProgress = true
  },

i'm also running the following nvim version:

NVIM v0.10.1
Build type: Release
LuaJIT 2.1.1723675123
Run "nvim -V1 -v" for more info

i should also mention that the other basedpyright features like hover, definition, rename, etc. do work even when the autocompletion doesn't, so that leads me to think there's possibly something very fiddly with the nvim-cmp setup on my side or something along those lines, as opposed to a basedpyright issue.

would very much appreciate if you had some insights or hints as to how i go about tracing this randomness in the autocompletion (and apologies for the novel-length question ha!)

[VonHeikemen]

The first thing I would do is put a print("hellooooo") statement in the config function of nvim-cmp. To see if the plugin is loaded.

You can add lazy = false property. To make sure lazy.nvim is loading the plugin at startup.

[aggonis]

thanks @VonHeikemen. turns out the real culprit was my config setup for hrsh7th/cmp-nvim-lsp, specifically the following bit:

config = function()
    require('cmp').setup({
      sources = {
        name = 'nvim_lsp',
      }
    })
  end,

i misunderstood what the README.md was suggesting, the sources setup was applicable to the main nvim-cmp 🤦‍♂️ oh well... 🫠

so for those setting up this via lazy.nvim, all's needed for the cmp-nvim-lsp part is:

return {
  'hrsh7th/cmp-nvim-lsp',
}

one more question for you if i may. i saw you mentioned in one of your blogposts that nvim-0.11 adds native autocompletion support, which is indeed what i found on their roadmap as well, does this mean that nvim-cmp will be redundant at that point?