Add Mason and Null-ls plugins for Neovim

init.lua

@@ -467,18 +467,6 @@ local servers = {
   -- pyright = {},
   -- rust_analyzer = {},
   -- tsserver = {},
-  efm = {
-    init_options = { documentFormatting = true },
-    settings = {
-      rootMarkers = { ".git/" },
-      languages = {
-        prettier = {
-          formatCommand = 'prettierd "${INPUT}"',
-          formatStdin = true,
-        }
-      }
-    }
-  },
   lua_ls = {
     Lua = {
       workspace = { checkThirdParty = false },

lua/custom/plugins/mason-null-ls.lua

@@ -0,0 +1,19 @@
+return {
+  "jay-babu/mason-null-ls.nvim",
+  event = { "BufReadPre", "BufNewFile" },
+  dependencies = {
+    "williamboman/mason.nvim",
+    "jose-elias-alvarez/null-ls.nvim",
+  },
+  config = function()
+    require("mason-null-ls").setup({
+      -- list of formatters & linters for mason to install
+      ensure_installed = {
+        "prettierd", -- ts/js formatter
+        "eslint_d",  -- ts/js linter
+      },
+      -- auto-install configured formatters & linters (with null-ls)
+      automatic_installation = true,
+    })
+  end,
+}

lua/custom/plugins/null-ls.lua

@@ -0,0 +1,36 @@
+return {
+  "jose-elias-alvarez/null-ls.nvim",
+  config = function()
+    local null_ls     = require("null-ls")
+
+    local formatting  = null_ls.builtins.formatting  -- to setup formatters
+    local diagnostics = null_ls.builtins.diagnostics -- to setup linters
+
+    local augroup     = vim.api.nvim_create_augroup("LspFormatting", {})
+
+    null_ls.setup({
+      sources = {
+        formatting.prettierd,
+        diagnostics.eslint_d
+      },
+      on_attach = function(current_client, bufnr)
+        if current_client.supports_method("textDocument/formatting") then
+          vim.api.nvim_clear_autocmds({ group = augroup, buffer = bufnr })
+          vim.api.nvim_create_autocmd("BufWritePre", {
+            group = augroup,
+            buffer = bufnr,
+            callback = function()
+              vim.lsp.buf.format({
+                filter = function(client)
+                  --  only use null-ls for formatting instead of lsp server
+                  return client.name == "null-ls"
+                end,
+                bufnr = bufnr,
+              })
+            end,
+          })
+        end
+      end
+    })
+  end
+}