regexGraphemeStringLiterals

Reports string literals inside character classes with the v flag that contain multiple graphemes.

✅ This rule is included in the ts stylisticStrict presets.

When using the v flag (Unicode sets mode), character classes support string literals using the \q{...} syntax. These string literals are intended to match a single grapheme or character sequence that behaves as a unit. Using multi-grapheme strings inside these literals confuses the distinction between string matching and character class behavior.

If you need to match multi-character strings, use regular alternation with a non-capturing group instead of string literals inside character classes.

Examples

❌ Incorrect

const pattern = /[\q{abc}]/v;

const pattern = /[\q{a|bc}]/v;

const pattern = /[\q{hello|world}]/v;

✅ Correct

const pattern = /[\q{a|b|c}]/v;

const pattern = /[\q{©️|®️}]/v;

const pattern = /[\q{🇦🇨|🇦🇩}]/v;

const pattern = /[\q{👨‍👩‍👧‍👦}]/v;

// Use regular alternation for multi-character strings
const pattern = /(?:hello|world)/v;

Options

This rule is not configurable.

When Not To Use It

If you intentionally use multi-grapheme string literals in character classes and understand the semantic difference between string matching and character class behavior, you might prefer to disable this rule.

Further Reading

• MDN: Regular expressions - Unicode character class escape
• MDN: Regular expressions - Character class

Equivalents in Other Linters

• ESLint: regexp/grapheme-string-literal