Found empty character classes in regular expressions JS-0010
Bug risk
Major
Empty character classes in regular expressions do not match anything. This is generally the result of a typo.
Bad Practice
/^abc[]/.test("abcdefg"); // false
"abcdefg".match(/^abc[]/); // null
Recommended
/^abc/.test("abcdefg"); // true
"abcdefg".match(/^abc/); // ["abc"]
/^abc[a-z]/.test("abcdefg"); // true
"abcdefg".match(/^abc[a-z]/); // ["abcd"]