Disallow Empty Character Classes (no-empty-class)
Replacement notice: This rule was removed in ESLint v1.0 and replaced by the no-empty-character-class rule.
Empty character classes in regular expressions do not match anything and can result in code that may not work as intended.
var foo = /^abc/;
This rule is aimed at highlighting possible typos and unexpected behavior in regular expressions which may arise from the use of empty character classes.
The following patterns are considered problems:
var foo = /^abc/; /^abc/.test(foo); bar.match(/^abc/);
The following patterns are not considered problems:
var foo = /^abc/; var foo = /^abc[a-z]/; var bar = new RegExp("^abc");
This rule was introduced in ESLint 0.0.9 and removed in 1.0.0-rc-1.