dotfiles/nvim/lua/configs/bufferline.lua

local bufferline = require('bufferline')

vim.api.nvim_create_user_command('BufferRename', function(opts)
  local bufnr = vim.api.nvim_get_current_buf()
  local function rename(name)
    if name == nil or not vim.api.nvim_buf_is_valid(bufnr) then
      return
    end
    name = vim.trim(name)
    vim.b[bufnr].bufferline_name = name ~= '' and name or nil
    vim.cmd('redrawtabline')
  end

  if opts.bang then
    rename('')
  elseif opts.args ~= '' then
    rename(opts.args)
  else
    vim.ui.input({
      prompt = 'Buffer label (empty to reset): ',
      default = vim.b[bufnr].bufferline_name or '',
    }, rename)
  end
end, { nargs = '*', bang = true, desc = 'Rename bufferline label (use ! to reset)' })

bufferline.setup {
  options = {
    name_formatter = function(buf)
      return vim.b[buf.bufnr].bufferline_name or buf.name
    end,
    mode = "buffers", -- set to "tabs" to only show tabpages instead
    style_preset = bufferline.style_preset.default,
    themable = true,
    indicator = {
      icon = '▎',
      style = 'icon',
    },
    groups = {
      items = {
        {
          name = 'tornado',
          matcher = function(buf)
            return (buf.path or ""):lower():match("tornado")
          end,
        },
        {
          name = 'gornado',
          matcher = function(buf)
            return (buf.path or ""):lower():match("gornado")
          end,
        },
        {
          name = 'tests',
          matcher = function(buf)
            return (buf.name or ""):lower():match("*test*%.cpp$")
          end,
        },
        {
          name = 'code',
          matcher = function(buf)
            return (buf.name or ""):lower():match("%.h$")
                or (buf.name or ""):lower():match("%.c$")
                or (buf.name or ""):lower():match("%.cpp$")
          end,
        },
      },
      hidden = false,
    },
    buffer_close_icon = '󰅖',
    modified_icon = '● ',
    close_icon = ' ',
    left_trunc_marker = ' ',
    right_trunc_marker = ' ',
    max_name_length = 18,
    max_prefix_length = 15,
    truncate_names = true,
    tab_size = 18,
    offsets = {
      {
        filetype = "NvimTree",
        text = "File Explorer",
        text_align = "left",
        separator = true
      }
    },
    color_icons = true,
    get_element_icon = function(element)
      local icon, hl = require('nvim-web-devicons').get_icon_by_filetype(element.filetype, { default = false })
      return icon, hl
    end,
    show_buffer_icons = true,
    show_buffer_close_icons = true,
    show_close_icon = true,
    show_tab_indicators = true,
    separator_style = "slant",
    enforce_regular_tabs = false,
    always_show_bufferline = true,
    auto_toggle_bufferline = true,
    hover = {
      enabled = true,
      delay = 200,
      reveal = { 'close' }
    },
    pick = {
      alphabet = "abcdefghijklmopqrstuvwxyzABCDEFGHIJKLMOPQRSTUVWXYZ1234567890",
    },
  }
}