Found control characters in regular expressions JS-0004
Bug risk
5 months ago
—
5 months old
Unexpected control character(s) in regular expression: \x1f, \x1f.
375 : String.fromCharCode((n >> 10) | 55296, (1023 & n) | 56320))
376 );
377 },
378 re = /([\0-\x1f\x7f]|^-?\d)|^-$|[^\0-\x1f\x7f-\uFFFF\w-]/g, 379 ie = function (e, t) {
380 return t
381 ? "\0" === eUnexpected control character(s) in regular expression: \x1f, \x1f.
375 : String.fromCharCode((n >> 10) | 55296, (1023 & n) | 56320))
376 );
377 },
378 re = /([\0-\x1f\x7f]|^-?\d)|^-$|[^\0-\x1f\x7f-\uFFFF\w-]/g, 379 ie = function (e, t) {
380 return t
381 ? "\0" === eUnexpected control character(s) in regular expression: \x1f, \x1f.
375 : String.fromCharCode((n >> 10) | 55296, (1023 & n) | 56320))
376 );
377 },
378 re = /([\0-\x1f\x7f]|^-?\d)|^-$|[^\0-\x1f\x7f-\uFFFF\w-]/g, 379 ie = function (e, t) {
380 return t
381 ? "\0" === eUnexpected control character(s) in regular expression: \x1f, \x1f.
375 : String.fromCharCode((n >> 10) | 55296, (1023 & n) | 56320))
376 );
377 },
378 re = /([\0-\x1f\x7f]|^-?\d)|^-$|[^\0-\x1f\x7f-\uFFFF\w-]/g, 379 ie = function (e, t) {
380 return t
381 ? "\0" === e
Description
Control characters are special, invisible characters in the ASCII range 0-31. These characters are rarely used in JavaScript strings, so a regular expression containing these characters is most likely a mistake.
Bad Practice
const pattern1 = /\x1f/;
const pattern2 = new RegExp("\x1f");
Recommended
const pattern1 = /\x20/;
const pattern2 = new RegExp("\x20");