refactoring to use config options from lua module

lua/lib/format.lua

@@ -1,17 +1,7 @@
+local config = require 'lib/config'
+
 local api = vim.api
 
-local HAS_DEV_ICONS = api.nvim_call_function('exists', { "*WebDevIconsGetFileTypeSymbol" }) == 1
-
-local function get(var, fallback)
-    if api.nvim_call_function('exists', { 'g:'..var }) == 1 then
-        return api.nvim_get_var(var)
-    else
-        return fallback
-    end
-end
-
-local SHOW_FOLDER_ICON = get('lua_tree_show_folders', 1) == 1
-
 local function get_padding(depth)
     local str = ""
 
@@ -24,7 +14,7 @@ local function get_padding(depth)
 end
 
 local function default_icons(_, isdir, open)
-    if isdir == true and SHOW_FOLDER_ICON then
+    if isdir == true and config.SHOW_FOLDER_ICON then
         if open == true then return " " end
         return " "
     end
@@ -69,7 +59,7 @@ local function dev_icons(pathname, isdir, open)
 end
 
 local function get_icon_func_gen()
-    if HAS_DEV_ICONS then
+    if config.HAS_DEV_ICONS then
         return dev_icons
     else
         return default_icons
@@ -132,7 +122,7 @@ local function highlight_line(buffer)
             highlight('LuaTreeFolderName', line, 0, -1)
 
         elseif node.dir == true then
-            if SHOW_FOLDER_ICON then
+            if config.SHOW_FOLDER_ICON then
                 text_start = text_start + 4
                 highlight('LuaTreeFolderIcon', line, 0, text_start)
             end
@@ -150,7 +140,7 @@ local function highlight_line(buffer)
         elseif is_pic(node.path .. node.name) then
             highlight('LuaTreeImageFile', line, text_start + gitlen, -1)
 
-        elseif HAS_DEV_ICONS then
+        elseif config.HAS_DEV_ICONS then
             for k, v in pairs(HIGHLIGHT_GROUPS) do
                 if string.match(node.name, k) ~= nil then
                     text_start = text_start + 4