lean3ls

https://github.com/leanprover/lean-client-js/tree/master/lean-language-server

Lean installation instructions can be found here.

Once Lean is installed, you can install the Lean 3 language server by running

npm install -g lean-language-server

Setup

require'lspconfig'.lean3ls.setup{}

Default values

cmd = { "lean-language-server", "--stdio", "--", "-M", "4096", "-T", "100000" }
filetypes = { "lean3" }
on_new_config = function(config, root)
      if not util.path.is_file(root .. '/leanpkg.toml') then
        return
      end
      if not config.cmd_cwd then
        config.cmd_cwd = root
      end
    end,
root_dir = function(fname)
      return util.root_pattern 'leanpkg.toml'(fname) or util.find_git_ancestor(fname) or util.path.dirname(fname)
    end,