eslint-plugin-regexp

What is eslint-plugin-regexp?

eslint-plugin-regexp is an ESLint plugin that provides linting rules for regular expressions. It helps developers write more efficient, readable, and secure regular expressions by catching common mistakes and suggesting improvements.

What are eslint-plugin-regexp's main functionalities?

No Unnecessary Escape

This rule disallows unnecessary escape characters in regular expressions. In the example, the backslash before the dot is unnecessary and should be removed.

/* eslint regexp/no-useless-escape: 'error' */
const regex = /\./;

No Obscure Character Class

This rule disallows obscure character class ranges that can be confusing or error-prone. In the example, the character class is clear and does not contain obscure ranges.

/* eslint regexp/no-obscure-range: 'error' */
const regex = /[a-zA-Z]/;

No Unnecessary Quantifier

This rule disallows unnecessary quantifiers in regular expressions. In the example, the quantifier {1} is unnecessary and should be removed.

/* eslint regexp/no-useless-quantifier: 'error' */
const regex = /a{1}/;

No Empty Character Class

This rule disallows empty character classes in regular expressions. In the example, the character class is empty and should be corrected.

/* eslint regexp/no-empty-character-class: 'error' */
const regex = /[]/;

Other packages similar to eslint-plugin-regexp

eslint-plugin-security

eslint-plugin-security is an ESLint plugin that helps identify potential security issues in JavaScript code. While it covers a broader range of security concerns, it includes some rules related to regular expressions, such as detecting potential ReDoS (Regular Expression Denial of Service) vulnerabilities. It is more general in scope compared to eslint-plugin-regexp.

eslint-plugin-unicorn

eslint-plugin-unicorn is a collection of various ESLint rules aimed at improving code quality and consistency. It includes some rules for regular expressions, such as preventing potential ReDoS attacks and suggesting more readable patterns. However, it is not as focused on regular expressions as eslint-plugin-regexp.

README

Introduction

eslint-plugin-regexp is ESLint plugin for finding RegExp mistakes and RegExp style guide violations.

:name_badge: Features

This ESLint plugin provides linting rules relate to better ways to help you avoid problems when using RegExp.

• Find the wrong usage of regular expressions, and their hints.
• Enforces a consistent style of regular expressions.
• Find hints for writing optimized regular expressions.

You can check on the Online DEMO.

:book: Documentation

See documents.

:cd: Installation

npm install --save-dev eslint eslint-plugin-regexp

Requirements

• ESLint v6.0.0 and above
• Node.js v8.10.0 and above

:book: Usage

Create .eslintrc.* file to configure rules. See also: http://eslint.org/docs/user-guide/configuring.

Example .eslintrc.js:

module.exports = {
  extends: [
    // add more generic rulesets here, such as:
    // 'eslint:recommended',
    'plugin:regexp/recommended'
  ],
  rules: {
    // override/add rules settings here, such as:
    // 'regexp/rule-name': 'error'
  }
}

Configuration

This plugin provides one config:

• plugin:regexp/recommended ... This is the recommended configuration for this plugin.
  See lib/configs/recommended.ts for details.

:white_check_mark: Rules

The --fix option on the command line automatically fixes problems reported by rules which have a wrench :wrench: below.
The rules with the following star :star: are included in the plugin:regexp/recommended config.

Rule ID	Description
regexp/letter-case	enforce into your favorite case	:wrench:
regexp/match-any	enforce match any character style	:star::wrench:
regexp/negation	enforce use of escapes on negation	:wrench:
regexp/no-assertion-capturing-group	disallow capturing group that captures assertions.	:star:
regexp/no-dupe-characters-character-class	disallow duplicate characters in the RegExp character class	:star:
regexp/no-dupe-disjunctions	disallow duplicate disjunctions
regexp/no-empty-group	disallow empty group	:star:
regexp/no-empty-lookarounds-assertion	disallow empty lookahead assertion or empty lookbehind assertion	:star:
regexp/no-escape-backspace	disallow escape backspace ([\b])	:star:
regexp/no-invisible-character	disallow invisible raw character	:star::wrench:
regexp/no-legacy-features	disallow legacy RegExp features
regexp/no-octal	disallow octal escape sequence	:star:
regexp/no-unused-capturing-group	disallow unused capturing group
regexp/no-useless-backreference	disallow useless backreferences in regular expressions
regexp/no-useless-character-class	disallow character class with one character	:wrench:
regexp/no-useless-dollar-replacements	disallow useless $ replacements in replacement string
regexp/no-useless-escape	disallow unnecessary escape characters in RegExp
regexp/no-useless-exactly-quantifier	disallow unnecessary exactly quantifier	:star:
regexp/no-useless-non-capturing-group	disallow unnecessary Non-capturing group	:wrench:
regexp/no-useless-non-greedy	disallow unnecessary quantifier non-greedy (?)	:wrench:
regexp/no-useless-range	disallow unnecessary range of characters by using a hyphen	:wrench:
regexp/no-useless-two-nums-quantifier	disallow unnecessary {n,m} quantifier	:star:
regexp/order-in-character-class	enforces elements order in character class	:wrench:
regexp/prefer-character-class	enforce using character class	:wrench:
regexp/prefer-d	enforce using \d	:star::wrench:
regexp/prefer-escape-replacement-dollar-char	enforces escape of replacement $ character ($$).
regexp/prefer-plus-quantifier	enforce using + quantifier	:star::wrench:
regexp/prefer-quantifier	enforce using quantifier	:wrench:
regexp/prefer-question-quantifier	enforce using ? quantifier	:star::wrench:
regexp/prefer-range	enforce using character class range	:wrench:
regexp/prefer-regexp-exec	enforce that RegExp#exec is used instead of String#match if no global flag is provided
regexp/prefer-regexp-test	enforce that RegExp#test is used instead of String#match and RegExp#exec	:wrench:
regexp/prefer-star-quantifier	enforce using * quantifier	:star::wrench:
regexp/prefer-t	enforce using \t	:star::wrench:
regexp/prefer-unicode-codepoint-escapes	enforce use of unicode codepoint escapes	:wrench:
regexp/prefer-w	enforce using \w	:star::wrench:

:beers: Contributing

Welcome contributing!

Please use GitHub's Issues/PRs.

Development Tools

• npm test runs tests and measures coverage.
• npm run update runs in order to update readme and recommended configuration.

:lock: License

See the LICENSE file for license rights and limitations (MIT).