nixos-configuration/home-manager/modules/neovim.nix

{ lib, nixosConfig, config, pkgs, ... }:
{
  home.sessionVariables = {
    EDITOR = "nvim";
  };
  programs.neovim = {
    enable = true;
    vimAlias = true;
    extraConfig = ''
      " use space as leader
      let mapleader = " "

      colorscheme NeoSolarized

      """""""""""""""""
      " Swap and undo "
      set noswapfile
      set nobackup
      if has('persistent_undo')
          " yay persistent undo
          :silent !mkdir -p ~/.local/vim-undo
          set undofile
          set undodir=~/.local/vim-undo
      endif

      cabbr <expr> %% expand('%:p:h')

      set listchars=trail:·,precedes:«,extends:»,eol:↲,tab:▸\
      nmap <silent> <leader>c :set list!<CR>

      set smartcase
      set hlsearch
      nnoremap <silent> <CR> :nohlsearch<CR>:set nolist<CR><CR>

      " highlight whitespace
      highlight ExtraWhitespace ctermbg=red guibg=red
      highlight WrongIndent ctermbg=2 guibg=blue
      match ExtraWhitespace /\s\+$/
      augroup highlight_extra_whitespace
          autocmd BufWinEnter * match ExtraWhitespace /\s\+$/
          autocmd InsertEnter * match ExtraWhitespace /\s\+\%#\@<!$/
          autocmd InsertLeave * match ExtraWhitespace /\s\+$/
          autocmd BufWinLeave * call clearmatches()
      augroup END

      let g:deoplete#enable_at_startup = 1

      sign define LspDiagnosticsSignError text=🟥
      sign define LspDiagnosticsSignWarning text=🟠
      sign define LspDiagnosticsSignInformation text=🟣
      sign define LspDiagnosticsSignHint text=🟢

      nnoremap <silent> gd    <cmd>lua vim.lsp.buf.definition()<CR>
      nnoremap <silent> gi    <cmd>lua vim.lsp.buf.implementation()<CR>
      nnoremap <silent> gr    <cmd>lua vim.lsp.buf.references()<CR>
      nnoremap <silent> gD    <cmd>lua vim.lsp.buf.declaration()<CR>
      nnoremap <silent> ge    <cmd>lua vim.lsp.diagnostic.set_loclist()<CR>
      nnoremap <silent> K     <cmd>lua vim.lsp.buf.hover()<CR>
      nnoremap <silent> <leader>f    <cmd>lua vim.lsp.buf.formatting()<CR>
      nnoremap <silent> <leader>rn    <cmd>lua vim.lsp.buf.rename()<CR>

      nnoremap <silent> <leader>a <cmd>lua vim.lsp.buf.code_action()<CR>
      xmap <silent> <leader>a <cmd>lua vim.lsp.buf.range_code_action()<CR>

      lua require('init')
    '';

    # nix-env -f '<nixpkgs>' -qaP -A vimPlugins
    plugins = with pkgs.vimPlugins; [
      #Valloric/MatchTagAlways
      #frankier/neovim-colors-solarized-truecolor-only
      #nvie/vim-rst-tables
      NeoSolarized
      deoplete-nvim
      editorconfig-vim
      nvim-lspconfig
      vim-gitgutter
      vim-indent-guides
      vim-nix
      vim-puppet
      vim-terraform
    ];
  };

  xdg.configFile."nvim/lua/init.lua".text = builtins.concatStringsSep "\n" (
    [
      ''
        -- init.lua
        -- this configuration applies to servers and workstations
      ''
    ] ++ lib.optional nixosConfig.jalr.workstation.enable ''
      -- this configuration applies to workstations only
      -- https://github.com/neovim/nvim-lspconfig/blob/master/doc/server_configurations.md
      local lsp = require('lspconfig')

      -- C and C++
      lsp.ccls.setup {
        on_attach = on_attach,
        cmd = { "${pkgs.ccls}/bin/ccls" },
      }

      -- Nix
      lsp.rnix.setup {
        on_attach = on_attach,
        cmd = { "${pkgs.rnix-lsp}/bin/rnix-lsp" },
      }

      -- Python
      lsp.pylsp.setup {
        on_attach = on_attach,
        cmd = { "${pkgs.python310Packages.python-lsp-server}/bin/pylsp" },
        settings = {
          -- https://github.com/python-lsp/python-lsp-server/blob/develop/CONFIGURATION.md
          pylsp = {
            plugins = {
              flake8 = {
                enabled = true;
                executable = "${pkgs.python310Packages.flake8}/bin/flake8";
              };
              jedi_completion = { enabled = true; };
              jedi_definition = { enabled = true; };
              jedi_hover = { enabled = true; };
              jedi_references = { enabled = true; };
              jedi_signature_help = { enabled = true; };
              jedi_symbols = { enabled = true; };
              mccabe = { enabled = true; };
              preload = { enabled = true; };
              pycodestyle = { enabled = true; };
              pyflakes = { enabled = true; };
              rope_completion = { enabled = true; };
              yapf = { enabled = true; };
            };
          };
        };
      }

      -- Ruby
      lsp.solargraph.setup {
        on_attach = on_attach,
        cmd = { "${pkgs.solargraph}/bin/solargraph", "stdio" },
      }

      -- Rust
      lsp.rust_analyzer.setup {
        on_attach = on_attach,
        cmd = { "${pkgs.rust-analyzer}/bin/rust-analyzer" },
      }

      -- Bash
      lsp.bashls.setup {
        on_attach = on_attach,
        cmd = { "${pkgs.nodePackages.bash-language-server}/bin/bash-language-server", "start" },
      }

      -- Terraform
      lsp.terraform_lsp.setup {
        on_attach = on_attach,
        cmd = { "${pkgs.terraform-lsp}/bin/terraform-lsp", "serve" },
      }

      -- YAML
      lsp.yamlls.setup {
        on_attach = on_attach,
        cmd = { "${pkgs.nodePackages.yaml-language-server}/bin/yaml-language-server", "--stdio" },
      }
    ''
  );
}