regexUnnecessaryNonCapturingGroups

Reports non-capturing groups that can be removed without changing the meaning of the regex.

✅ This rule is included in the ts stylistic presets.

Reports non-capturing groups (?:...) that serve no purpose and can be removed without changing the meaning of the regular expression.

Note that groups are necessary when:

• They apply a quantifier to multiple elements: /(?:ab)+/
• They group alternations that are not the only element: /a(?:b|c)d/
• Removing them would create escape sequences: /\x4(?:1)/
• They wrap a quantified element for an outer quantifier: /(?:a{2})+/

Examples

❌ Incorrect

const pattern = /(?:abcd)/;

const pattern = /(?:a)+/;

const pattern = /(?:a|b)/;

✅ Correct

const pattern = /abcd/;

const pattern = /a+/;

const pattern = /a|b/;

Options

This rule is not configurable.

When Not To Use It

If you prefer to keep non-capturing groups for readability or organizational purposes, you might want to disable this rule.

Further Reading

• MDN: Groups and backreferences
• MDN: Regular expressions

Equivalents in Other Linters

• ESLint: regexp/no-useless-non-capturing-group