add field mask

lib/text_utils.rb

@@ -2,6 +2,8 @@
 
 module TextUtils
   RTL_REGEXP = /[\p{Hebrew}\p{Arabic}]/
+  MASK_REGEXP = /[^\s\-_\[\]\(\)\+\?\.\,]/
+  MASK_SYMBOL = 'X'
 
   module_function
 
@@ -13,6 +15,10 @@ module TextUtils
     false
   end
 
+  def mask_value(text)
+    text.to_s.gsub(MASK_REGEXP, MASK_SYMBOL)
+  end
+
   def maybe_rtl_reverse(text)
     if text.match?(RTL_REGEXP)
       TwitterCldr::Shared::Bidi