:PossessionSave closes all non-visible buffers

[mawkler]

:PossessionSave closes any buffer that's not in a window. To reproduce, use the following config:

Click to expand

-- Ignore default config and plugins
vim.opt.runtimepath:remove(vim.fn.expand('~/.config/nvim'))
vim.opt.packpath:remove(vim.fn.expand('~/.local/share/nvim/site'))

-- Append test directory
local test_dir = vim.fn.expand('~/code-other/nvim-test-config')
vim.opt.runtimepath:append(vim.fn.expand(test_dir))
vim.opt.packpath:append(vim.fn.expand(test_dir))

-- Install packer
local install_path = test_dir .. '/pack/packer/start/packer.nvim'
local install_plugins = false

if vim.fn.empty(vim.fn.glob(install_path)) > 0 then
  vim.cmd('!git clone https://github.com/wbthomason/packer.nvim ' .. install_path)
  vim.cmd('packadd packer.nvim')
  install_plugins = true
end

local packer = require('packer')

packer.init({
  package_root = test_dir .. '/pack',
  compile_path = test_dir .. '/plugin/packer_compiled.lua'
})

packer.startup(function()
  function Use(module)
    use(require(string.format('configs.%s', module)))
  end

  -- Packer can manage itself
  packer.use 'wbthomason/packer.nvim'


  use { 'jedrzejboczar/possession.nvim',
    requires = { 'nvim-lua/plenary.nvim' },
    config = function()
      require('possession').setup()
    end
  }

  if install_plugins then
    packer.sync()
  else
    -- load plugins at your earliest convenience
    vim.defer_fn(function()
      vim.cmd('doautocmd User LoadPlugins')
    end, 1)
  end
end)

And then run this:

> nvim -u path/to/file/above.lua foo bar baz -c ':buffers' -c ':PossessionSave test' -c ':buffers'

Here's the output of the first :buffers:

  1 %a   "foo"                          line 0
  2      "bar"                          line 0
  3      "baz"                          line 0

And here's the output of the second :buffers:

  1 %a   "foo"                          line 1

You get the same behaviour if you run :PossessionSave manually from inside Neovim.

[jedrzejboczar]

This is most likely caused by setup option plugins.delete_hidden_buffers (runs on before_save if you have buffers in your sessionoptions). You can use plugins = { delete_hidden_buffers = false } to disable this behaviour. What to do with windows/buffers depends on specific user preference, so this is configurable. See :h possession-delete-hidden-buffers for more information. If you disable it you probably want to enable :h possession-delete-buffers to delete all buffers before loading another session.

[mawkler]

I see, but why does delete_hidden_buffers delete hidden buffers if I have 'buffers' set in 'sessionoptions'? The option 'buffers' states that I want to include hidden buffers. Shouldn't this :

vim.o.sessionoptions:match('buffer') and 'before_save'

instead be this:

not vim.o.sessionoptions:match('buffer') and 'before_save'

Here's what :help sessionoptions says:

Each word enables saving and restoring something:

[...]

"buffers: hidden and unloaded buffers, not just those in windows"

[jedrzejboczar]

Yeah, maybe it's confusing, it's partially due to "historic" reasons. I added this because I don't like saving hidden buffers, because I can easily have tens of "throwaway" buffers open due to jumping through the code. And these would accumulate when changing sessions, so buffers from session A would still be there in session B (and then would be saved). At that time there was no possession.delete_buffers. I still don't like storing hidden buffers due to my kind of workflow, but I assume it's essential for some people workflows (especially when someone likes using bufferline instead of tabline). Maybe it's not the best default, but I don't want to change it now, because I would also have to change the default for delete_buffers and I'd rather avoid breaking changes, when it's quite easy for anyone to just disable/enable these to their liking.