my-nvim-setup/lua/plugins/configs/bufferline.lua

local present, bufferline = pcall(require, "bufferline")

if not present then
   return
end

vim.cmd [[
 function! Toggle_theme(a,b,c,d)
   lua require('base46').toggle_theme()
 endfunction

 function! Quit_vim(a,b,c,d)
     qa
 endfunction
]]

local options = {
   options = {
      offsets = { { filetype = "NvimTree", text = "", padding = 1 } },
      buffer_close_icon = "",
      modified_icon = "",
      close_icon = "",
      show_close_icon = false,
      left_trunc_marker = " ",
      right_trunc_marker = " ",
      max_name_length = 14,
      max_prefix_length = 13,
      tab_size = 20,
      show_tab_indicators = true,
      enforce_regular_tabs = false,
      view = "multiwindow",
      show_buffer_close_icons = true,
      separator_style = "thin",
      always_show_bufferline = true,
      diagnostics = false,
      themable = true,

      custom_areas = {
         right = function()
            return {
               { text = "%@Toggle_theme@" .. vim.g.toggle_theme_icon .. "%X" },
               { text = "%@Quit_vim@ %X" },
            }
         end,
      },

      custom_filter = function(buf_number)
         -- Func to filter out our managed/persistent split terms
         local present_type, type = pcall(function()
            return vim.api.nvim_buf_get_var(buf_number, "term_type")
         end)

         if present_type then
            if type == "vert" then
               return false
            elseif type == "hori" then
               return false
            end
            return true
         end

         return true
      end,
   },
}

-- check for any override
options = require("core.utils").load_override(options, "akinsho/bufferline.nvim")

bufferline.setup(options)