improve completion config

- show what we are completing from with symbol on left
- improving results ordering

after/plugin/cmp.lua

@@ -15,35 +15,57 @@ local neogen = require('neogen')
 require("luasnip.loaders.from_vscode").lazy_load()
 
 cmp.setup {
-  snippet = {
-    expand = function(args)
-      luasnip.lsp_expand(args.body)
-    end,
-  },
-
   sources = cmp.config.sources({
-    { name = 'nvim_lsp', keyword_length = 3 },
+    { name = 'nvim_lsp', priority = 999 },
+    { name = 'luasnip_choice', priority = 750 },
+    { name = 'buffer', max_item_count = 3 },
+    { name = 'async_path', max_item_count = 5 },
     { name = 'nvim_lua' },
-    { name = 'luasnip_choice' },
-    { name = 'async_path' },
-    { name = 'buffer', keyword_length = 3, max_item_count = 7 },
-    { name = 'calc' },
     { name = 'neorg' },
+    { name = 'calc' },
+    { name = 'cmdline' },
   }),
+
   window = {
     completion = {
+      scrollbar = false,
       border = { ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ' },
       winhighlight = "Normal:WinBarNC,FloatBorder:WinBarNC,Search:WinBarNC",
     },
     documentation = {
+      max_width = 80,
       border = { ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ' },
       winhighlight = "Normal:WinBarNC,FloatBorder:WinBarNC,Search:WinBarNC",
     }
   },
+
   view = {
     entries = { name = 'custom', selection_order = 'near_cursor' },
   },
 
+  formatting = {
+    fields = {'menu', 'abbr', 'kind'},
+    format = function(entry, item)
+      local menu_icon = {
+        nvim_lsp = 'λ',
+        nvim_lua = 'v',
+        calc = '+',
+        luasnip = '%',
+        buffer = '@',
+        path = '#',
+      }
+
+      item.menu = menu_icon[entry.source.name]
+      return item
+    end,
+  },
+
+  snippet = {
+    expand = function(args)
+      luasnip.lsp_expand(args.body)
+    end,
+  },
+
   -- mappings -----------------------------------------------------------------
   mapping = cmp.mapping.preset.insert({
     ["<Tab>"] = cmp.mapping(function(fallback)