feat: add symbols option to fileformat (#401)

* doc: add symbol to fileformat component specific option

README.md

@@ -483,6 +483,23 @@ sections = {
 }
 ```
 
+#### fileformat component options
+
+```lua
+sections = {
+  lualine_a = {
+    {
+      'fileformat',
+      symbols = {
+        unix = '', -- e712
+        dos = '', -- e70f
+        mac = '', -- e711
+      }
+    }
+  }
+}
+```
+
 #### filename component options
 
 ```lua

lua/lualine/components/fileformat.lua

@@ -3,18 +3,28 @@
 local M = require('lualine.component'):extend()
 
 -- stylua: ignore
-M.icon = {
+local symbols = {
   unix = '', -- e712
-  dos  = '', -- e70f
-  mac  = ''  -- e711
+  dos = '', -- e70f
+  mac = '', -- e711
 }
 
-M.update_status = function(self)
-  if self.options.icons_enabled and not self.options.icon then
-    local format = vim.bo.fileformat
-    return M.icon[format] or format
+-- Initializer
+function M:init(options)
+  -- Run super()
+  M.super.init(self, options)
+  -- Apply default symbols
+  self.symbols = vim.tbl_extend('keep', self.options.symbols or {}, symbols)
+end
+
+-- Function that runs everytime statusline is updated
+function M:update_status()
+  local format = vim.bo.fileformat
+  if self.options.icons_enabled then
+    return self.symbols[format] or format
+  else
+    return format
   end
-  return vim.bo.fileformat
 end
 
 return M