spacevim/bundle/nvim-lspconfig/lua/lspconfig/server_configurations/sumneko_lua.lua

local util = require 'lspconfig.util'

return {
  default_config = {
    filetypes = { 'lua' },
    root_dir = util.find_git_ancestor,
    single_file_support = true,
    log_level = vim.lsp.protocol.MessageType.Warning,
    settings = { Lua = { telemetry = { enable = false } } },
  },
  docs = {
    package_json = 'https://raw.githubusercontent.com/sumneko/vscode-lua/master/package.json',
    description = [[
https://github.com/sumneko/lua-language-server

Lua language server.

`lua-language-server` can be installed by following the instructions [here](https://github.com/sumneko/lua-language-server/wiki/Build-and-Run).

**By default, lua-language-server doesn't have a `cmd` set.** This is because nvim-lspconfig does not make assumptions about your path. You must add the following to your init.vim or init.lua to set `cmd` to the absolute path ($HOME and ~ are not expanded) of your unzipped and compiled lua-language-server.

```lua
local system_name
if vim.fn.has("mac") == 1 then
  system_name = "macOS"
elseif vim.fn.has("unix") == 1 then
  system_name = "Linux"
elseif vim.fn.has('win32') == 1 then
  system_name = "Windows"
else
  print("Unsupported system for sumneko")
end

-- set the path to the sumneko installation; if you previously installed via the now deprecated :LspInstall, use
local sumneko_root_path = vim.fn.stdpath('cache')..'/lspconfig/sumneko_lua/lua-language-server'
local sumneko_binary = sumneko_root_path.."/bin/"..system_name.."/lua-language-server"

local runtime_path = vim.split(package.path, ';')
table.insert(runtime_path, "lua/?.lua")
table.insert(runtime_path, "lua/?/init.lua")

require'lspconfig'.sumneko_lua.setup {
  cmd = {sumneko_binary, "-E", sumneko_root_path .. "/main.lua"};
  settings = {
    Lua = {
      runtime = {
        -- Tell the language server which version of Lua you're using (most likely LuaJIT in the case of Neovim)
        version = 'LuaJIT',
        -- Setup your lua path
        path = runtime_path,
      },
      diagnostics = {
        -- Get the language server to recognize the `vim` global
        globals = {'vim'},
      },
      workspace = {
        -- Make the server aware of Neovim runtime files
        library = vim.api.nvim_get_runtime_file("", true),
      },
      -- Do not send telemetry data containing a randomized but unique identifier
      telemetry = {
        enable = false,
      },
    },
  },
}
```
]],
    default_config = {
      root_dir = [[root_pattern(".git") or bufdir]],
    },
  },
}