Checking a variable for one word with one to ten letters lowercase only?
Try this regular expression: /^[a-z]{1,10}$/.test('wakaluba').
/^[a-z]{1,10}$/.test(null);
/^[a-z]{1,10}$/.test(undefined);
Both should obviously fail, but return true. srsly, WTF JS?
This happens because regex.test() converts its parameter to a string:
String(null) // "null"
The string "null" matches the regular expression /^[a-z]{1,10}$/