Confused by when to use config vs opts

[tbelvin2000]

Hello,

I was setting up my neovim config and doing my best to follow the recommendation to always use opts instead of config when possible.
However, when loading Tree-sitter I ran into issues with it not highlighting python files without me explicitly enabling highlighting using TSBufEnable highlight.
After adding

config = function(_, opts)
    require('nvim-treesitter.configs').setup(opts)
end,

to the end of my treesitter.lua it seems to work fine.

I am confused as to why this was required, and if I need to do so for all of the plugins where I use opts={...} instead of config=... and .setup({}) as recommended in the documentation.

Thanks for any help clarifying this!

[Shadow53]

Maybe that opts={} only applies to the top-level plugin, i.e. nvim-treesitter, and not sub-plugins like nvim-treesitter.configs? That's my best guess.

[dpetka2001]

opts = {} means that the default config function will be used. The default config function will do require("main_lua_module").setup().

The main Lua module is the module where the setup function is defined and called upon. For the case of nvim-treesitter (for master branch at least as it used to be the case), the setup function was defined in nvim-treesitter.configs module and not nvim-treesitter. By default lazy.nvim assumes that it's usually defined in the top-level module (that would be nvim-treesitter, but not all plugins do that because it's just a convention after all and not followed through by all plugin authors as they might have different preferences with regards to the design of their plugin).

That's why you either have to define main = "nvim-treesitter.configs" in the plugin spec for nvim-treesitter and be able to use opts like you normally do without config or just use the config function where you explicitly require("nvim-treesitter.configs").setup(opts) yourself.