Add snippet engine for cmp

common/neovim/lua/plugins.lua

@@ -4,6 +4,11 @@ if #vim.fn.glob(packer_install_path) == 0 then
 	vim.api.nvim_command'packadd packer.nvim'
 end
 
+local has_words_before = function()
+  local line, col = unpack(vim.api.nvim_win_get_cursor(0))
+  return col ~= 0 and vim.api.nvim_buf_get_lines(0, line - 1, line, true)[1]:sub(col, col):match("%s") == nil
+end
+
 local packer = require'packer'
 packer.startup(function()
 	local plugins = {
@@ -45,21 +50,38 @@ packer.startup(function()
 				'nvim-lua/plenary.nvim',
 			}
 		},
+		{
+			'nvim-telescope/telescope-fzf-native.nvim',
+			run = 'make',
+		},
+		{
+			'tzachar/cmp-fuzzy-path',
+			requires = {'hrsh7th/nvim-cmp', 'tzachar/fuzzy.nvim'},
+		},
 		-- TODO: add keymap <leader>ig for toggling these
 		'lukas-reineke/indent-blankline.nvim', -- indentation guide lines
+		'L3MON4D3/LuaSnip',
+
 		'neovim/nvim-lspconfig', -- language server configuration helper
     'williamboman/nvim-lsp-installer', -- plugin containing installation commands for many language servers
 		'hrsh7th/cmp-nvim-lsp', -- add lsp to completion engine
 		'hrsh7th/cmp-buffer', -- add buffer information to completion engine
 		'hrsh7th/cmp-path', -- add filesystem information to complete enging
 		'hrsh7th/cmp-cmdline', -- add completion for vim commands
+		'saadparwaiz1/cmp_luasnip',
 		{
 			-- completion engine
 			'hrsh7th/nvim-cmp',
 			config = function()
 				local cmp = require'cmp'
+				local luasnip = require'luasnip'
 
 				cmp.setup{
+					snippet = {
+						expand = function(args)
+							luasnip.lsp_expand(args.body)
+						end,
+					},
 					mapping = {
 						['<C-b>'] = cmp.mapping(cmp.mapping.scroll_docs(-4), { 'i', 'c' }),
 						['<C-f>'] = cmp.mapping(cmp.mapping.scroll_docs(4), { 'i', 'c' }),
@@ -70,16 +92,41 @@ packer.startup(function()
 							c = cmp.mapping.close(),
 						},
 						['<CR>'] = cmp.mapping.confirm{select = true}, -- Accept currently selected item. Set `select` to `false` to only confirm explicitly selected items.
+						["<Tab>"] = cmp.mapping(function(fallback)
+							if cmp.visible() then
+								cmp.select_next_item()
+							elseif luasnip.expand_or_jumpable() then
+								luasnip.expand_or_jump()
+							elseif has_words_before() then
+								cmp.complete()
+							else
+								fallback()
+							end
+						end, { "i", "s" }),
+						["<S-Tab>"] = cmp.mapping(function(fallback)
+							if cmp.visible() then
+								cmp.select_prev_item()
+							elseif luasnip.jumpable(-1) then
+								luasnip.jump(-1)
+							else
+								fallback()
+							end
+						end, { "i", "s" }),
 					},
-					sources = cmp.config.sources{
+					sources = cmp.config.sources({
 						{ name = 'nvim_lsp' },
+						{ name = 'luasnip' },
+					}, {
 						{ name = 'buffer' },
-					},
+						{ name = 'path' },
+						{ name = 'fuzzy_path' },
+					}),
 				}
 
 				cmp.setup.cmdline('/', {
 					sources = {
 						{name = 'buffer'},
+						{name = 'fuzzy_path'},
 					}
 				})