[BUG] Harpoon error when setting settings

[k2on]

Field	Description
Plugin	harpoon
Nixpkgs	25.05
Home Manager	25.05

• I have read the FAQ and my bug is not listed there.

Description

When I add settings to harpoon I get this error:

Error detected while processing /home/max/.config/nvim/init.lua:
E5113: Error while calling lua chunk: vim/shared.lua:0: after the second argument: expected table, got boolean
stack traceback:
        [C]: in function 'error'
        vim/shared.lua: in function 'validate'
        vim/shared.lua: in function 'tbl_extend'
        ...k/myNeovimPackages/start/harpoon2/lua/harpoon/config.lua:267: in function 'merge_config'
        ...ack/myNeovimPackages/start/harpoon2/lua/harpoon/init.lua:148: in function 'setup'
        /home/max/.config/nvim/init.lua:146: in main chunk

Minimal, Reproducible Example (MRE)

programs.nixvim = {
  plugins.harpoon = {
    enable = true;
    settings = {
      save_on_toggle = true;
    };
  };
}

[k2on]

The generated init.lua contains this:

require("harpoon"):setup({ save_on_toggle = true })

But I believe is SHOULD be:

require("harpoon"):setup({ settings = { save_on_toggle = true } })

[k2on]

Here is how I temporarily fixed the issue.

programs.nixvim = {
  plugins.harpoon = {
    enable = true;
    settings = {
       # nested settings fixes the issue
      settings = { save_on_toggle = true; };
    };
  };
}

[GaetanLepage]

@k2on 's analysis is correct. But this is not a bug, this is nixvim's expected behavior.

The plugins.harpoons.settings option is a freeform option that let's you pass arbitrary values to harpoon's :setup method.
As harpoon is expecting a settings key in the setup argument, you'll end up having two settings in Nixvim:

plugins.harpoon = {
  enable = true;

  # Everything will be passed to `require('harpoon'):setup()`
  settings = {
    # The following will become a lua table: `{ settings = { foo = 'bar' } }`
    settings.foo = "bar";
  };
};

Although it might appear as strange in this case (having 2 settings), it is consistent across Nixvim's code base (well, for plugins that have been modernized somewhat recently).