Restoring a session containing a neo-tree sidebar breaks neo-tree

[dhazel]

Thanks for the great plugin!

Neovim version: 0.8.2
OS: Windows 10

Steps to reproduce:

1. Open neovim
2. Open the neo-tree sidebar, :Neotree
3. Save the session, :mksession mysession.vim
4. Close neovim
5. Open neovim
6. Restore the session, :source mysession.vim
7. Observe that the sidebar is created but neo-tree does not render in the sidebar
8. Attempt to toggle the neotree sidebar, :Neotree
9. Observe that neo-tree does not render and an error is thrown in messages:

Error executing vim.schedule lua callback: ...vim-data/lazy/neo-tree.nvim/lua/neo-tree/ui/renderer.lua:867: Failed to rename buffer
stack traceback:
	[C]: in function 'nvim_buf_set_name'
	...vim-data/lazy/neo-tree.nvim/lua/neo-tree/ui/renderer.lua:867: in function 'create_window'
	...vim-data/lazy/neo-tree.nvim/lua/neo-tree/ui/renderer.lua:1015: in function 'draw'
	...vim-data/lazy/neo-tree.nvim/lua/neo-tree/ui/renderer.lua:1177: in function 'show_nodes'
	...ree.nvim/lua/neo-tree/sources/filesystem/lib/fs_scan.lua:98: in function 'render_context'
	...ree.nvim/lua/neo-tree/sources/filesystem/lib/fs_scan.lua:126: in function <...ree.nvim/lua/neo-tree/sources/filesystem/lib/fs_scan.lua:125>

[nhat-vo]

Hi! Indeed, this looks like a bug. The neo-tree buffer was saved along with the session, and neo-tree is unable to overwrite that buffer when it is created again. A workaround would be to close the tree before creating the session. I will have a look to see if there is any way to do this automatically.

[nyngwang]

@nhat-vo Does #748 resolve this now?

[nhat-vo]

Yes, thanks for reminding me. I thought the issue will automatically be closed on PR merge.

[cseickel]

Yes, thanks for reminding me. I thought the issue will automatically be closed on PR merge.

The issue will get automatically closed on release in this repo. It's not a big deal either way if you want to close it on merge to main though.

[ehaynes99]

I don't think this actually works. The function executes, but restoring a session like nvim -S Session.vim, I end up with the restored session having these buffers:

:buffers
  9 #    "~/all-workspaces/external/neo-tree.nvim/README.md" line 1
 10 %a   "lua/neo-tree/ui/renderer.lua" line 32
 11  a   "neo-tree filesystem [1]"      line 0

the neo-tree filesystem buffer is normal size and blank. Toggling the tree resumes the proper behavior.

Also, plugins like auto-session open session files like this:

silent source <SESSION_FILE>

In this case, the clean_neotree_buffers function is never called.

[nhat-vo]

Good point! I actually thought of adding the cleanup step right after a session was load, but somehow forgot about it.

[nyngwang]

@nhat-vo Can confirm that your fix does work, and thank you! A minor issue is that there is a blink after restoring the session (so I did see the empty split was there and got closed during restoring)

[nhat-vo]

@nyngwang thanks for helping me test! Unfortunately, the neo-tree buffer will be loaded on session restore, which causes the blink that you see. I couldn't find any workaround to that, as the built-in :mksession does not provide any functionality to exclude a buffer or to emit an event to handle closing the neo-tree buffer.

[PriceHiller]

Unfortunately, at least for me, this fix causes the file tree to randomly close on opening some files in git projects.

It's related to clean_invalid_neotree_buffers. I don't have an autosession plugin or anything like that, so I'm not quite sure what's loading a session that would kick off the closing of the neotree sidebar.