nvim: add external formatter support

modules/programs/nvim/default.nix

@@ -44,6 +44,7 @@ in
       extraPackages = with pkgs; [
         sumneko-lua-language-server
         nil
+        stylua
       ];
       plugins = with pkgs.vimPlugins; [
         catppuccin-nvim
@@ -55,6 +56,7 @@ in
         lualine-lsp-progress
         lualine-nvim
         luasnip
+        formatter-nvim
         neogit
         noice-nvim
         nui-nvim # for noice-nvim

modules/programs/nvim/init.lua

@@ -133,38 +133,6 @@ cmp.setup({
   },
 })
 
--- The nvim-cmp almost supports LSP's capabilities so You should advertise it to LSP servers..
-local capabilities = require("cmp_nvim_lsp").default_capabilities()
-
-local lspconfig = require("lspconfig")
-local on_attach_def = function(_, bufnr)
-  wk.register({
-    K = { vim.lsp.buf.hover, "show info" },
-    ["<leader>l"] = {
-      name = "lsp",
-      d = { vim.diagnostic.open_float, "open diagnostic window" },
-      n = { vim.diagnostic.goto_next, "next error" },
-      p = { vim.diagnostic.goto_prev, "prev error" },
-      c = { vim.lsp.buf.code_action, "code action" },
-      r = { vim.lsp.buf.rename, "rename" },
-      f = {
-        function()
-          vim.lsp.buf.format({ async = true })
-        end,
-        "format",
-      },
-    },
-    g = {
-      name = "goto",
-      r = { vim.lsp.buf.references, "references" },
-      d = { vim.lsp.buf.definition, "definition" },
-      D = { vim.lsp.buf.declaration, "declaration" },
-      i = { vim.lsp.buf.implementation, "implementation" },
-      t = { vim.lsp.buf.type_definition, "type defininition" },
-    },
-  }, { noremap = true, silent = true, buffer = bufnr })
-end
-
 ---merge tables
 ---@param ... table[]
 ---@return table
@@ -193,6 +161,80 @@ local function table_merge(...)
   return result
 end
 
+-- Provides the Format, FormatWrite, FormatLock, and FormatWriteLock commands
+require("formatter").setup({
+  -- Enable or disable logging
+  logging = true,
+  -- Set the log level
+  log_level = vim.log.levels.WARN,
+  -- All formatter configurations are opt-in
+  filetype = {
+    -- Formatter configurations for filetype "lua" go here
+    -- and will be executed in order
+    lua = {
+      -- "formatter.filetypes.lua" defines default configurations for the
+      -- "lua" filetype
+      require("formatter.filetypes.lua").stylua,
+    },
+
+    -- Use the special "*" filetype for defining formatter configurations on
+    -- any filetype
+    ["*"] = {
+      -- "formatter.filetypes.any" defines default configurations for any
+      -- filetype
+      require("formatter.filetypes.any").remove_trailing_whitespace,
+    },
+  },
+})
+wk.register({
+  ["="] = { "<cmd>Format<cr>", "format (formatter)" },
+}, { noremap = true, silent = true })
+
+-- The nvim-cmp almost supports LSP's capabilities so You should advertise it to LSP servers..
+local capabilities = require("cmp_nvim_lsp").default_capabilities()
+
+local lspconfig = require("lspconfig")
+local on_attach_def = function(client, bufnr)
+  local options = { noremap = true, silent = true } -- default options
+  local buffer_options = table_merge(options, { buffer = bufnr }) -- buffer specific options
+
+  -- set format keybinding
+  -- prefere lsp formatting over external formatter
+  if client.server_capabilities.documentFormattingProvider then
+    local modes = { "n", "v" }
+    for _, mode in ipairs(modes) do
+      wk.register({
+        ["="] = {
+          function()
+            vim.lsp.buf.format({ async = true })
+          end,
+          "format (lsp)",
+        },
+      }, table_merge(buffer_options, { mode = mode }))
+    end
+  end
+
+  wk.register({
+    K = { vim.lsp.buf.hover, "show info" },
+    ["<leader>l"] = {
+      name = "lsp",
+      d = { vim.diagnostic.open_float, "open diagnostic window" },
+      n = { vim.diagnostic.goto_next, "next error" },
+      p = { vim.diagnostic.goto_prev, "prev error" },
+      c = { vim.lsp.buf.code_action, "code action" },
+      r = { vim.lsp.buf.rename, "rename" },
+    },
+    g = {
+      name = "goto",
+      r = { vim.lsp.buf.references, "references" },
+      d = { vim.lsp.buf.definition, "definition" },
+      D = { vim.lsp.buf.declaration, "declaration" },
+      i = { vim.lsp.buf.implementation, "implementation" },
+      t = { vim.lsp.buf.type_definition, "type defininition" },
+    },
+  }, buffer_options)
+end
+
 local lspconfig_default_options = {
   on_attach = on_attach_def,
   capabilities = capabilities,