setup lsp and cmp

after/plugin/cmp.lua

@@ -0,0 +1,20 @@
+local cmp = require("cmp")
+
+cmp.setup({
+  snippet = {
+    expand = function(args)
+      require("luasnip").lsp_expand(args.body)
+    end,
+  },
+  sources = cmp.config.sources({
+    { name = "nvim_lsp" },
+    { name = "nvim_lsp_signature_help" },
+    { name = "buffer" },
+    { name = "luasnip" },
+  }),
+  formatting = {
+    format = require("lspkind").cmp_format({
+      mode = "symbol_text",
+    }),
+  },
+})

after/plugin/lsp.lua

@@ -1,6 +1,12 @@
+require("lspkind").init({
+  mode = "symbol_text",
+})
+
+local capabilities = require("cmp_nvim_lsp").default_capabilities()
 local lspconfig = require("lspconfig")
 
 lspconfig.lua_ls.setup({
+  capabilities = capabilities,
   on_init = function(client)
     local path = client.workspace_folders[1].name
     if not vim.loop.fs_stat(path .. "/.luarc.json") and not vim.loop.fs_stat(path .. "/.luarc.jsonc") then
@@ -23,4 +29,6 @@ lspconfig.lua_ls.setup({
   end,
 })
 
-lspconfig.nixd.setup({})
+lspconfig.nixd.setup({
+  capabilities = capabilities,
+})

lua/plugins.lua

@@ -6,10 +6,16 @@ return require("packer").startup(function(use)
   use("akinsho/toggleterm.nvim")
   use("wesleimp/stylua.nvim")
   use("neovim/nvim-lspconfig")
+  use("hrsh7th/nvim-cmp")
+  use("hrsh7th/cmp-nvim-lsp")
+  use("hrsh7th/cmp-nvim-lsp-signature-help")
+  use("L3MON4D3/LuaSnip")
+  use("saadparwaiz1/cmp_luasnip")
+  use("hrsh7th/cmp-buffer")
+  use("onsails/lspkind.nvim")
 
   use({
     "akinsho/bufferline.nvim",
-    as = "bufferline.nvim",
     requires = {
       { "nvim-tree/nvim-web-devicons" },
     },