eslint-plugin-math

0.13.1 verified Sat Apr 25 auth: no javascript

ESLint plugin for Math object and Number linting. Current version 0.13.1, peer dependency ESLint >=8.57.0, requires Node ^18 or >=20. Provides ~30 rules including prefer-math-trunc, prefer-math-pow, prefer-number-is-finite. Supports flat config (eslint.config.js) and legacy .eslintrc. Offers a recommended config and fixable suggestions. Built on eslint-type-tracer for efficient type detection. Designed to catch common Math/Number anti-patterns and promote modern alternatives. Notable for its focus on correctness (e.g., prefer-math-sum-precise for floating point).

Common errors

error Error [ERR_REQUIRE_ESM]: require() of ES Module /node_modules/eslint-plugin-math/dist/index.js from /project/eslint.config.js not supported. ↓

cause Plugin is ESM-only and cannot be required via CommonJS.

fix

Use import eslintPluginMath from 'eslint-plugin-math' in an ESM context or use dynamic import.

error ESLint couldn't find the plugin "eslint-plugin-math". (Note: plugins are not resolved relative to the config file.) ↓

cause Plugin not installed or not in node_modules, or ESLint cannot resolve it.

fix

Run npm install --save-dev eslint-plugin-math eslint and ensure config references the plugin correctly.

error Configuration for rule "math/prefer-math-trunc" is invalid: Value "off" is the only valid severity for deprecated rules. ↓

cause Rule 'math/prefer-math-trunc' might be deprecated in future version.

fix

Check rule docs and use 'error' or 'warn' if still supported; or use 'off' to disable.

Warnings

breaking Plugin no longer supports ESLint <8.57.0 as of v0.10.0. ↓

fix Upgrade ESLint to >=8.57.0 or pin plugin to <0.10.0.

breaking Plugin no longer supports Node <18 as of v0.10.0. ↓

fix Upgrade Node to ^18 or >=20 or pin plugin to <0.10.0.

breaking Legacy config 'plugin:math/recommended' renamed to 'plugin:math/recommended-legacy' in v0.10.0. ↓

fix Use 'plugin:math/recommended-legacy' in .eslintrc files. Flat config users should use eslintPluginMath.configs.recommended.

gotcha Flat config import must be default import; named exports 'configs' and 'rules' are also available but require destructuring. ↓

fix Use `import eslintPluginMath from 'eslint-plugin-math'` or `import { configs } from 'eslint-plugin-math'`.

deprecated Option `reportBitwise` in rule 'prefer-math-trunc' was deprecated in v0.9.0. ↓

fix Remove the option; behavior is now default.

Install

npm install eslint-plugin-math

yarn add eslint-plugin-math

pnpm add eslint-plugin-math

Imports

default

wrong

const eslintPluginMath = require('eslint-plugin-math')

correct

import eslintPluginMath from 'eslint-plugin-math'

ESM-only; CommonJS require not supported. Use dynamic import if needed in CJS.

configs

wrong

import eslintPluginMath from 'eslint-plugin-math'; const configs = eslintPluginMath.configs

correct

import { configs } from 'eslint-plugin-math'

Named export 'configs' is available since v0.10.0. Using default and destructuring is fine but redundant.

rules

wrong

const { rules } = require('eslint-plugin-math')

correct

import { rules } from 'eslint-plugin-math'

Named export 'rules' is available since v0.10.0.

Quickstart

Shows how to use the plugin with flat config, including recommended config and custom rules.

import eslintPluginMath from 'eslint-plugin-math';

export default [
  eslintPluginMath.configs.recommended,
  {
    rules: {
      'math/prefer-math-trunc': 'error',
      'math/no-static-infinity-calculations': 'warn',
    },
  },
];