[request] Callback or event for when there's no next buffer

[bennypowers]

Please expose a config field or aucmd event to customize the behaviour when the last buffer is closed. For example, a user may want to open their dashboard plugin when closing all buffers.

Current:

README.md

If no buffer other than the target buffer was open, bufdelete.nvim creates an empty buffer and switches to it instead.

Desired

require'bufdelete'.setup {
  -- string | function
  on_close_last_buffer = ':Alpha'
}

or

vim.api.nvim_create_augroup('bufdelete', { clear = true })
vim.api.nvim_create_autocmd('User', {
  group = 'bufdelete',
  pattern = 'bufdelete_empty',
  command = ':Alpha',
})

Alternatives

This is possible without changing bufdelete.nvim:

---@author kikito
---@see https://codereview.stackexchange.com/questions/268130/get-list-of-buffers-from-current-neovim-instance
local function get_listed_buffers()
  local buffers = {}
  local len = 0
  for buffer = 1, vim.fn.bufnr('$') do
    if vim.fn.buflisted(buffer) == 1 then
      len = len + 1
      buffers[len] = buffer
    end
  end

  return buffers
end

function M.bufdelete(bufnum)
  require 'bufdelete'.bufdelete(bufnum, true)
  if #M.get_listed_buffers() == 1 and vim.api.nvim_buf_get_name(0) == '' then
    vim.cmd [[:Alpha]]
  end
end

But then the user needs to import and call that function anywhere they want this behaviour, for example in bufferline.nvim config:

bufferline.setup {
  options = {
    right_mouse_command = U.bufdelete,
    close_command = U.bufdelete,
  }
}

But this means the user has to remember each callsite. An event or callback field would allow the user to write that function once and use it automatically wherever.

[famiu]

Allowing that sort of configuration is hard since this plugin doesn't use a setup() function nor do I plan to add one since it would be a massive breaking change to require calling a setup() function to use the plugin.

[bennypowers]

How about an event? something like BDeletePre would let the user open a 'default' buffer

[famiu]

How about an event? something like BDeletePre would let the user open a 'default' buffer

Why not just use the builtin BufDelete autocmd

[bennypowers]

That will also be called when renaming a buffer, which screws up alpha-nvim (dashboard plugin). Probably there's a workaround for that 🤷

This request is just to add some ergonomics to this plugin though

[famiu]

Done, it's been added

[bennypowers]

Thank you!

an implementation: goolord/alpha-nvim#85 (comment)