modules/lsp: init

Co-authored-by: Matt Sturgeon <matt@sturgeon.me.uk>

modules/default.nix

@@ -18,6 +18,7 @@
     ./highlights.nix
     ./keymaps.nix
     ./lazyload.nix
+    ./lsp.nix
     ./lua-loader.nix
     ./opts.nix
     ./output.nix

modules/lsp.nix

@@ -0,0 +1,151 @@
+{
+  lib,
+  config,
+  ...
+}:
+let
+  inherit (lib) mkOption types;
+  inherit (lib.nixvim) toLuaObject;
+
+  cfg = config.lsp;
+
+  serverType = types.submodule {
+    options = {
+      enable = lib.mkEnableOption "the language server";
+
+      activate = lib.mkOption {
+        type = types.bool;
+        description = ''
+          Whether to call `vim.lsp.enable()` for this server.
+        '';
+        default = true;
+        example = false;
+      };
+
+      package = lib.mkOption {
+        type = with types; nullOr package;
+        default = null;
+        description = ''
+          Package to use for this language server.
+
+          Alternatively, the language server should be available on your `$PATH`.
+        '';
+      };
+
+      config = mkOption {
+        type = with types; attrsOf anything;
+        description = ''
+          Configurations for each language server.
+        '';
+        default = { };
+        example = {
+          cmd = [
+            "clangd"
+            "--background-index"
+          ];
+          root_markers = [
+            "compile_commands.json"
+            "compile_flags.txt"
+          ];
+          filetypes = [
+            "c"
+            "cpp"
+          ];
+        };
+      };
+    };
+  };
+in
+{
+  options.lsp = {
+    luaConfig = lib.mkOption {
+      type = lib.types.pluginLuaConfig;
+      default = { };
+      description = ''
+        Lua code configuring LSP.
+      '';
+    };
+
+    inlayHints = {
+      enable = lib.mkEnableOption "inlay hints globally";
+    };
+
+    servers = mkOption {
+      type = types.attrsOf serverType;
+      description = ''
+        LSP servers to enable and/or configure.
+
+        This option is implemented using neovim's `vim.lsp` lua API.
+        If you prefer to use [nvim-lspconfig], see [`plugins.lsp`].
+
+        [nvim-lspconfig]: https://github.com/neovim/nvim-lspconfig
+        [`plugins.lsp`]: https://nix-community.github.io/nixvim/plugins/lsp/index.html
+      '';
+      default = { };
+      example = {
+        "*".config = {
+          root_markers = [ ".git" ];
+          capabilities.textDocument.semanticTokens = {
+            multilineTokenSupport = true;
+          };
+        };
+        luals.enable = true;
+        clangd = {
+          enable = true;
+          config = {
+            cmd = [
+              "clangd"
+              "--background-index"
+            ];
+            root_markers = [
+              "compile_commands.json"
+              "compile_flags.txt"
+            ];
+            filetypes = [
+              "c"
+              "cpp"
+            ];
+          };
+        };
+      };
+    };
+  };
+
+  config =
+    let
+      enabledServers = lib.filterAttrs (_: v: v.enable) cfg.servers;
+    in
+    {
+      extraPackages = lib.pipe enabledServers [
+        builtins.attrValues
+        (builtins.catAttrs "package")
+      ];
+
+      lsp.luaConfig.content =
+        let
+          mkServerConfig =
+            name: props:
+            let
+              luaName = toLuaObject name;
+            in
+            ''
+              vim.lsp.config(${luaName}, ${toLuaObject props.config})
+            ''
+            + lib.optionalString props.activate ''
+              vim.lsp.enable(${luaName})
+            '';
+        in
+        lib.mkMerge (
+          lib.optional cfg.inlayHints.enable "vim.lsp.inlay_hint.enable(true)"
+          ++ lib.mapAttrsToList mkServerConfig enabledServers
+        );
+
+      extraConfigLua = lib.mkIf (cfg.luaConfig.content != "") ''
+        -- LSP {{{
+        do
+          ${cfg.luaConfig.content}
+        end
+        -- }}}
+      '';
+    };
+}

tests/test-sources/modules/lsp.nix

@@ -0,0 +1,30 @@
+{
+  example = {
+    lsp.servers = {
+      "*".config = {
+        root_markers = [ ".git" ];
+        capabilities.textDocument.semanticTokens = {
+          multilineTokenSupport = true;
+        };
+      };
+      luals.enable = true;
+      clangd = {
+        enable = true;
+        config = {
+          cmd = [
+            "clangd"
+            "--background-index"
+          ];
+          root_markers = [
+            "compile_commands.json"
+            "compile_flags.txt"
+          ];
+          filetypes = [
+            "c"
+            "cpp"
+          ];
+        };
+      };
+    };
+  };
+}