Making whitelist and blacklist case insensitive (#5)

* Making whitelist and blacklist case insensitive

* Updated README.rst mentioning case insensitive match

Author: Karan Mitroo

README.rst

@@ -38,9 +38,9 @@ Usages
 
 **is\_safe\_username** takes the following optional arguments:
 
--  ``whitelist``: a list of words that should be considered as always
+-  ``whitelist``: a case insensitive list of words that should be considered as always
    safe. Default: ``[]``
--  ``blacklist``: a list of words that should be considered as unsafe. Default: ``[]``
+-  ``blacklist``: a case insensitive list of words that should be considered as unsafe. Default: ``[]``
 -  ``max_length``: specify the maximun character a username can have. Default: ``None``
 -  ``regex``: regular expression string that must pass before the banned
    words is checked.

usernames/validators.py

@@ -28,8 +28,8 @@ def is_safe_username(
     if not re.match(regex, username):
         return False
     wordlist = get_reserved_wordlist()
-    whitelist = set(whitelist)
-    blacklist = set(blacklist)
+    whitelist = set([each_whitelisted_name.lower() for each_whitelisted_name in whitelist])
+    blacklist = set([each_blacklisted_name.lower() for each_blacklisted_name in blacklist])
     wordlist = wordlist - whitelist
     wordlist = wordlist.union(blacklist)
     return False if username.lower() in wordlist else True