fix(elixirls): smarter detection of root_dir for umbrella apps

[giddie]

Should fix issues identified following merge of #2910

[giddie]

OK, the CI informs me I've broken some rules. I can see in CONTRIBUTING that I shouldn't be using these functions. Is this something to do with "single file mode" passing different input to this function, so it needs to be handled differently?

[georgeguimaraes]

An idea to circumvent the dirname restriction:

[georgeguimaraes]

I think you don't need this check at all since we can trust there's a fname coming in.

[georgeguimaraes]

maybe this works?

local root_dir = util.root_pattern 'mix.exs'(maybe_umbrella_path) or util.root_pattern 'mix.exs'(child_or_root_path)

a bit redundant, but this way we're not using dirname and instead rely on the utils from lspconfig.

[giddie]

My main issue is that I don't understand what the constraints are here. Why can't we use dirname? Does this mean we can't use vim.fs.find either? Can @glepnir offer any guidance?

[glepnir]

wonder this not work ?

  local result = vim.fs.find ('mix.exs', {upward = true, limit = math.huge, path = fname})
  return #result > 0 and result[#reuslt] or uv.cwd()

[giddie]

But we need to return a directory path, right? Hence the use of dirname. Again, for me the question is really what functions we can and can't use, and why? What is different about this "single file mode"?

[glepnir]

no different. when single file mode enable it will use current dir as root.

[glepnir]

just set single_file_mode = true and remove cwd

[giddie]

I'm sorry, where should I be setting this? A search in nvim-lspconfig reveals zero instances of single_file_mode, so I'm all out of clues.

BTW, the code in this PR works just fine for me. As far as I'm concerned, and unless I can understand the constraints better, the problem seems to be the CI...?

[giddie]

Your suggestion below led me to find lspconfig-single-file-support in the lspconfig help. IIUC, the idea here is that if root_dir returns nil, and single_file_support is on, then this mode will be used?

I don't really get how this helps with the issue of dirname being rejected by the CI, though 😕

[glepnir]

yup dirname ci can ignore just fix lint .

[giddie]

Oh OK; great. Then I think we're good to go 🥳

[georgeguimaraes]

@glepnir Did you have a chance to review this? We'd appreciate your guidance here.

[glepnir]

Suggested change

	end,
	},
	end,
	single_file_support = true,
	},

[glepnir]

emm you forget here

[giddie]

Done 👍

[georgeguimaraes]

Great work everyone!

[towry]

It seems now elixir_ls will read .vscode's settings.

-- project_root (dir contains elixir and python projects)
  - .vscode/settings.json
  - app_stack_ex # (umbrella project)
  -- apps
  ---- sub_app/mix.exs
  -- mix.exs

If I have config in .vscode/settings.json:

{
  "elixirLS.projectDir": "app_stack_ex"
}

It works for vscode and vscode elixir extension, but not work for elixir in neovim, because elixirls in neovim will try to append this value to the umbrella project path, will give error like: app_stack_ex/app_stack_ex project not exists.

Solution

The solution is to add another .vscode/settings to the app_stack_ex folder, with projectDir set to .. Now it works for both vscode and elixirls in neovim.