programs.neovim: link packpath dir in XDG_DATA_HOME

[teto]

link the packpath in expected folder so that even unwrapped neovim can pick home-manager's plugins.

I sometimes need to run neovim not wrapped/configured by nix (when developing neovim or when other projects bring their own neovim in PATH). Currently they dont find plugins installed by home-manager in the cases where packpath is not set to the generated nix packpath directory. With this change, neovim can discover HM-installed plugins by itself.

NB: this PR needs this commit NixOS/nixpkgs#218786 from nixpkgs and thus tests will fail until it reaches unstable . Also I remember having a write issue when I first used this PR because home-manager wanted to manage the folder. Let me know if you hit that so we can find a workaround.

Description

Checklist

• Change is backwards compatible.

• Code formatted with ./format.

• Code tested through nix-shell --pure tests -A run.all.

• Test cases updated/added. See example.

• Commit messages are formatted like

  {component}: {description}
  
  {long description}
  

  See CONTRIBUTING for more information and recent commit messages for examples.

• If this PR adds a new module

  • Added myself as module maintainer. See example.

  • Added myself and the module files to .github/CODEOWNERS.

[RaitoBezarius]

LGTM as a NeoVim user.

[teto]

Ok I'll merge as I think it's more representative of how people want neovim to work (including myself). Remember that you may need to change ~/.local/share/nvim/ away so that HM can deal with it along with your package manager (I use lazy for instance).

[svrana]

I'm using a wrapped neovim and this change appears to cause one of my plugins? to be loaded twice. This results in getting an 'Already loaded' error message when I start neovim. To debug, I ran neovim like this neovim -V2nvim.log and searched for the 'Already loaded' string which I found at line 341

340 sourcing "/nix/store/r6h5damgnb72b2a9gf0hm0mlc09a0rn7-packdir-start/pack/myNeovimPackages/start/vim-latex-live-preview/plugin/latexlivepreview.vim"
Already loaded

(this is from the plugin named: vim-latex-live-preview)

If I search up the file for locations where it was previous loaded, I see it again at line 269.

If I comment out the plugin or remove the site/ directory from XDG_STATE_HOME the error goes away. I've placed the log file at https://gist.github.com/svrana/5c68f834a88eb52fd11e726c0a089906

-- edited

I can send a PR to remove the output from the plugin that's bugging me. I guess I'm wondering if it was intended to attempt to load the plugins twice for a wrapped neovim.

[teto]

I think this is because your neovim (like everyone else) is wrapped with a --cmd "set packpath..." . so it loads the one at that path plus the one in the standard folder. If you remove this line in nixpkgs https://github.com/nixos/nixpkgs/blob/4bb072f0a8b267613c127684e099a70e1f6ff106/pkgs/applications/editors/neovim/utils.nix#L111 it should fix the issue (it was in my plan to make it configurable in nixpkgs). Until I fix this in nixpkgs, maybe rollback your HM version ? sry I am not sure how to fix cleanly in HM.

[PatrickDaG]

I do not use home manager to manage my plugins, instead adding and configuring them directly in my vim config. This change forced the site directory to be a symlink to the nix store even though it is empty, which in turn prevents my vimconfig from being able to write it and add my plugins. I would suggest only doing this if there are plugins declared in the nix config, or making it optional.

[adrianord]

I am facing the same issue as @PatrickDaG. AstroNvim is managing my plugins with Packer, not using nix for plugin management at all, and this symlink is causing my configuration to fail.

[ncfavier]

I'm going to revert this for now until we figure this out

[ncfavier]

deb2f59#commitcomment-106637065:

Hi,
I manage my plugins via Packer.nvim and don't plan to migrate it to Home Manager. This way I can use my neovim config independently and just reference it from Home Manager to avoid duplication.

This change breaks my nix rebuild, since the site/pack directory generated by Packer is in the way of the new paths that are to be linked.

I'm not sure if there's a workaround to this or if it's just an issue in my setup. Has anyone an idea how to handle this w/o moving my neovim plugin management to Home Manager? Any help is much appreciated.

[teto]

home-manager should create the fullpath site/pack/HMpack instead so it doesn't conflict. This can be done adjusting some stuff in nixpkgs, but we could have worked around it in HM.

        "nvim/site/pack/HmPackages" = {
          # text = "toto";
          source = "${pkgs.vimUtils.packDir neovimConfig.packpathDirs}/pack/HmPackages";
        };

[nixos-discourse]

This pull request has been mentioned on NixOS Discourse. There might be relevant details there:

https://discourse.nixos.org/t/cant-load-local-plugin-in-home-manager-installed-neovim/47694/2