Update LSP config and DAP support

lua/debug.lua

@@ -0,0 +1,45 @@
+-- Setup nvim-cmp.
+local cmp = require'cmp'
+
+cmp.setup({
+  snippet = {
+    expand = function(args)
+      -- For `vsnip` user.
+      vim.fn["vsnip#anonymous"](args.body)
+
+      -- For `luasnip` user.
+      -- require('luasnip').lsp_expand(args.body)
+
+      -- For `ultisnips` user.
+      -- vim.fn["UltiSnips#Anon"](args.body)
+    end,
+  },
+  mapping = {
+    ['<C-d>'] = cmp.mapping.scroll_docs(-4),
+    ['<C-f>'] = cmp.mapping.scroll_docs(4),
+    ['<C-Space>'] = cmp.mapping.complete(),
+    ['<C-e>'] = cmp.mapping.close(),
+    ['<CR>'] = cmp.mapping.confirm({ select = true }),
+  },
+  sources = {
+    { name = 'nvim_lsp' },
+
+    -- For vsnip user.
+    { name = 'vsnip' },
+
+    -- For luasnip user.
+    -- { name = 'luasnip' },
+
+    -- For ultisnips user.
+    -- { name = 'ultisnips' },
+
+    { name = 'buffer' },
+  }
+})
+
+-- Setup lsp.
+metals_config = require("metals").bare_config
+metals_config.init_options.statusBarProvider = "on"
+metals_config.settings = { showImplicitArguments = true }
+metals_config.on_attach = on_attach
+metals_config.capabilities = require('cmp_nvim_lsp').update_capabilities(vim.lsp.protocol.make_client_capabilities())