regexControlCharacters

Reports control characters in regular expressions.

✅ This rule is included in the ts logical and logicalStrict presets.

Reports control characters (code points U+0000 through U+001F) in regular expressions. Control characters in regex patterns are rarely intentional and can indicate a mistake or copy-paste error.

Examples

Hex Escapes

❌ Incorre

AEconsB0patteAE< =sp ansty="le--0:#5CA7E4;--1:#3A68">81<1/sp ansty="le--0:#F78C6C;--1:#AA09">82\x<1fsp ansty="le--0:#D9F5DD;--1:#1111">1<1/sp ansty="le--0:#D6DEEB;--1:#403F">5<3;d ivclassNa="meco">

44AEco61B0pat446<88F spans="tyle--0:#D9F5DD;--1:#11">1<111/ spans="tyle--0:#F78C6C;--1:#AA">0982<\x20 spans="tyle--0:#D9F5DD;--1:#11">1<111/ spans="tyle--0:#D6DEEB;--1:#40">3<20/>

Unicode Escapes

❌ Incorre

AEconsB0patteAE< =sp ansty="le--0:#5CA7E4;--1:#3A68">81<1/sp ansty="le--0:#F78C6C;--1:#AA09">82\u00<1fsp ansty="le--0:#D9F5DD;--1:#1111">1<1/sp ansty="le--0:#D6DEEB;--1:#403F">5<3;d ivclassNa="meco">

44AEco61B0pat446<88F spans="tyle--0:#D9F5DD;--1:#11">1<111/ spans="tyle--0:#F78C6C;--1:#AA">0982\u<0020 spans="tyle--0:#D9F5DD;--1:#11">1<111/ spans="tyle--0:#D6DEEB;--1:#40">3<20/>

Control Character Escapes

❌ Incorre

AEconsB0patteAE< =sp ansty="le--0:#5CA7E4;--1:#3A68">81<1/sp ansty="le--0:#82AAFF;--1:#3B61">B0\1<1/sp ansty="le--0:#D6DEEB;--1:#403F">5<3;d ivclassNa="meco">

44AEco61B0pat446<88F spans="tyle--0:#D9F5DD;--1:#11">1<111/ spans="tyle--0:#5CA7E4;--1:#3A">6<88Fa spans="tyle--0:#D9F5DD;--1:#11">1<111/ spans="tyle--0:#D6DEEB;--1:#40">3

Options

This rule is not configurable.

When Not To Use It

If your application intentionally processes binary data or protocols that use control characters, and you need to match them in regular expressions, you might prefer to disable this rule.

Further Reading

• MDN: Control character
• MDN: Character escape

Equivalents in Other Linters

• Biome: noControlCharactersInRegex
• Deno: no-control-regex
• ESLint: no-control-regexregexp/no-control-character
• Oxlint: eslint/no-control-regex