Debugging Help for a new-ish nix user

[bassforce86]

I've created a standalone nixvim config, available here but i have an odd problem.

When running this against nix flake check . and nix run .#nvim it works as i'd expect (dashboard is loaded with my shortcuts)

But when I include this as a home-manager package in a home-manager flake, I get no start-up dashboard, just takes me straight to NetRW.

(home manager inclusion method is in the readme).

Has anyone else seen this behaviour from a standalone installation?

[MattSturgeon]

Are you installing the home-manager module or are you including the package you build in your standalone flake in home.packages?

See Standalone Usage in the docs.

Sidenote: a standalone package doesn't need to also be in a standalone flake, since one flake can have many outputs.

[bassforce86]

Forgive me for ruling out the obvious things first, but if your nixvim config works when run directly from its flake then the config is good.

Not at all - that's all part of triage, I am human, I make (many) mistakes 😄 . I came to a similar conclusion - hence the request for helping with debugging. The non-deterministic output confused me.

I use home-manager switch --flake . after a nix flake update in the home-manager repo, but still don't get the dashboard displayed when opening neovim via nvim, vim, or vi

[MattSturgeon]

Does nixvim-print-init after activating your hm config print the same thing as nixvim-print-init run within nix shell on your nixvim flake?

[bassforce86]

just to confirm i am making the correct calls to give you accurate information, running nix shell . in the neovim flake dir, is what you mean by checking the output in nix-shell?

Below is a side-by-side of nixvim-print-init from nix shell . (left) and nixvim-print-init from current home-manager generation.
Strangely, they are both referencing the same store reference... Which is not what I would expect when running something from within nix shell.

[MattSturgeon]

The files being the same in the nix-store is expected when both are built from the same config, since nix tries to be pure and deterministic.

The symlinks to the files will be different, since they are made available to your shell differently depending on how you activate/install them.

However something very strange is going on if you have the same init.lua file in both environments, but one of them works and the other does not.

Perhaps it is something impure from outside your nixvim config having an effect at runtime? At this point I'm just taking wild guesses though 😖

[bassforce86]

So, I've no idea why the non-deterministic-ness is occuring, but i've decided to work around the problem for now.

For anyone curious, here's the relevant autocmd: https://gitlab.com/bf86/flakes/neovim/-/blob/main/config/autocmd.nix?ref_type=heads#L81

And here, i've skipped loading netrw on startup just incase: https://gitlab.com/bf86/flakes/neovim/-/blob/main/config/globals.nix?ref_type=heads#L12

This now works as expected.