nix-community.nixvim/plugins/lsp/default.nix

{
  config,
  pkgs,
  lib,
  ...
}:
with lib; let
  cfg = config.plugins.lsp;
  helpers = import ../helpers.nix {inherit lib;};
in {
  imports = [
    ./language-servers
  ];

  options = {
    plugins.lsp = {
      enable = mkEnableOption "neovim's built-in LSP";

      keymaps = {
        silent = mkOption {
          type = types.bool;
          description = "Whether nvim-lsp keymaps should be silent";
          default = false;
        };

        diagnostic = mkOption {
          type = types.attrsOf types.str;
          description = "Mappings for `vim.diagnostic.<action>` functions.";
          example = {
            "<leader>k" = "goto_prev";
            "<leader>j" = "goto_next";
          };
          default = {};
        };

        lspBuf = mkOption {
          type = types.attrsOf types.str;
          description = "Mappings for `vim.lsp.buf.<action>` functions.";
          example = {
            "gd" = "definition";
            "gD" = "references";
            "gt" = "type_definition";
            "gi" = "implementation";
            "K" = "hover";
          };
          default = {};
        };
      };

      enabledServers = mkOption {
        type = with types;
          listOf (oneOf [
            str
            (submodule {
              options = {
                name = mkOption {
                  type = str;
                  description = "The server's name";
                };

                extraOptions = mkOption {
                  type = attrs;
                  description = "Extra options for the server";
                };
              };
            })
          ]);
        description = "A list of enabled LSP servers. Don't use this directly.";
        default = [];
      };

      onAttach = mkOption {
        type = types.lines;
        description = "A lua function to be run when a new LSP buffer is attached. The argument `client` and `bufnr` is provided.";
        default = "";
      };

      capabilities = mkOption {
        type = types.lines;
        description = "Lua code that modifies inplace the `capabilities` table.";
        default = "";
      };

      setupWrappers = mkOption {
        type = with types; listOf (functionTo str);
        description = "Code to be run to wrap the setup args. Takes in an argument containing the previous results, and returns a new string of code.";
        default = [];
      };

      preConfig = mkOption {
        type = types.lines;
        description = "Code to be run before loading the LSP. Useful for requiring plugins";
        default = "";
      };

      postConfig = mkOption {
        type = types.lines;
        description = "Code to be run after loading the LSP. This is an internal option";
        default = "";
      };
    };
  };

  config = let
    runWrappers = wrappers: s:
      if wrappers == []
      then s
      else (head wrappers) (runWrappers (tail wrappers) s);
  in
    mkIf cfg.enable {
      extraPlugins = [pkgs.vimPlugins.nvim-lspconfig];

      maps.normal = let
        diagnosticMaps =
          mapAttrs
          (key: action: {
            inherit (cfg.keymaps) silent;
            action = "vim.diagnostic.${action}";
            lua = true;
          })
          cfg.keymaps.diagnostic;

        lspBuf =
          mapAttrs
          (key: action: {
            inherit (cfg.keymaps) silent;
            action = "vim.lsp.buf.${action}";
            lua = true;
          })
          cfg.keymaps.lspBuf;
      in
        mkMerge [
          diagnosticMaps
          lspBuf
        ];

      # Enable all LSP servers
      extraConfigLua = ''
        -- LSP {{{
        do
          ${cfg.preConfig}

          local __lspServers = ${helpers.toLuaObject cfg.enabledServers}
          local __lspOnAttach = function(client, bufnr)
            ${cfg.onAttach}
          end
          local __lspCapabilities = function()
            capabilities = vim.lsp.protocol.make_client_capabilities()

            ${cfg.capabilities}

            return capabilities
          end

          local __setup = ${runWrappers cfg.setupWrappers "{
            on_attach = __lspOnAttach,
            capabilities = __lspCapabilities()
          }"}

          for i,server in ipairs(__lspServers) do
            if type(server) == "string" then
              require('lspconfig')[server].setup(__setup)
            else
              local options = ${runWrappers cfg.setupWrappers "server.extraOptions"}

              if options == nil then
                options = __setup
              else
                options = vim.tbl_extend("keep", options, __setup)
              end

              require('lspconfig')[server.name].setup(options)
            end
          end

          ${cfg.postConfig}
        end
        -- }}}
      '';
    };
}