[mini.comment] Commenting in insert mode

[n-crespo]

Here's a snippet I use for toggling comments in insert mode with (just like vsc*de):

{ 
  "nvim-mini/mini.comment",
  keys = {
    {
      "<C-/>",
      function()
        local api = vim.api
        local cursor = api.nvim_win_get_cursor(0)
        local row, col = cursor[1], cursor[2]
        local line = api.nvim_get_current_line()

        -- get commentstring components
        local cs = require("mini.comment").get_commentstring({ row, col + 1 })
        if cs == "" or not cs:find("%%s") then
          return
        end

        local prefix, suffix = cs:match("^(.-)%%s(.-)$")
        local trim_pre = prefix:gsub("%s+$", "") -- prefix without trailing space
        local trim_suf = suffix:gsub("^%s+", "") -- suffix without leading space

        -- capture leading whitespace and everything else
        local indent, content = line:match("^(%s*)(.*)")

        -- handle line that is either empty OR only contains the comment markers
        -- we use vim.pesc to treat markers as literal strings in the regex
        local pattern = "^" .. vim.pesc(prefix) .. vim.pesc(suffix) .. "$"
        local pattern_trimmed = "^" .. vim.pesc(trim_pre) .. vim.pesc(trim_suf) .. "$"

        if content == "" or content:match(pattern) or content:match(pattern_trimmed) then
          if content == "" then
            -- case: empty line -> add comment, keep indent
            api.nvim_set_current_line(indent .. prefix .. suffix)
            api.nvim_win_set_cursor(0, { row, #indent + #prefix })
          else
            -- case: only comment markers exist -> remove markers, keep indent
            api.nvim_set_current_line(indent)
            api.nvim_win_set_cursor(0, { row, #indent })
          end
          return
        end

        -- standard toggle logic for lines with actual content
        local is_commented = content:sub(1, #trim_pre) == trim_pre
        local offset = 0
        if is_commented then
          local space_match = content:match("^" .. vim.pesc(trim_pre) .. "(%s?)") or ""
          offset = -(#trim_pre + #space_match)
        else
          local padding = prefix:find("%s$") and 1 or 0
          offset = #trim_pre + padding
        end

        require("mini.comment").toggle_lines(row, row, { ref_position = { row, col + 1 } })
        api.nvim_win_set_cursor(0, { row, math.max(0, col + offset) })
      end,
      mode = "i",
      desc = "Toggle Comment Line",
    },
    {
      "<C-/>",
      "gcc",
      mode = "n",
      remap = true,
      desc = "Toggle Comment Line",
    },
    {
      "<C-/>",
      "gcgv",
      mode = "v",
      remap = true,
      desc = "Toggle Comment Line",
    },
  },
}

[echasnovski]

Thanks for sharing!

I'd still think that using plain '<Cmd>lua MiniComment.toggle_lines(vim.fn.line('.'), vim.fn.line('.'))<CR>' as mapping's right hand side would achieve a lot. But yeah, wouldn't work on blank lines.

Maybe <C-/> is a good enough default for 'mini.comment' to add commenting in Insert mode. That would work on blank and comment-leader-only lines. I'll think about it.