ESLint Friendly Formatter

4.0.1 verified Sat Apr 25 auth: no javascript

An ESLint formatter that produces output compatible with Sublime Text and iTerm2 'click to open file' functionality. Version 4.0.1 is the current stable release, with irregular updates. Key differentiators: file/line/column links that open in editors, clickable rule IDs linking to documentation, errors reported at end, and a summary with contextual code snippets. It is based on the default 'stylish' formatter but enhanced for terminal usability.

Common errors

error Cannot find module 'eslint-friendly-formatter' ↓

cause Module not installed or path incorrect when using --format in CLI.

fix

npm install --save-dev eslint-friendly-formatter; use --format ./node_modules/eslint-friendly-formatter/index.js

error formatter is not a function ↓

cause Wrong import style in ESM/CJS interop (e.g., require().default not used).

fix

Use const formatter = require('eslint-friendly-formatter').default if needed; for CJS use require('eslint-friendly-formatter') directly.

Warnings

breaking v4.0.0 changed from CommonJS to hybrid ESM/CJS, breaking direct require() without .default in some bundlers. ↓

fix Use default import: import formatter from 'eslint-friendly-formatter' or use require('eslint-friendly-formatter').default if needed.

deprecated v3.x and earlier are deprecated; upgrading to v4+ may break existing CJS code. ↓

fix Update to v4.0.0 or later and adjust imports as needed.

gotcha Clickable file links only work in terminals that support URIs like iTerm2 or Sublime Text; not all terminals. ↓

fix Test in your target terminal; configure editor to handle 'file://' URIs.

gotcha Formatter does not handle eslint --fix output; only displays messages. ↓

fix Use ESLint's --fix separately; this formatter only displays results.

Install

npm install eslint-friendly-formatter

yarn add eslint-friendly-formatter

pnpm add eslint-friendly-formatter

Imports

default

wrong

const formatter = require('eslint-friendly-formatter').default

correct

import formatter from 'eslint-friendly-formatter'

ESM default export equivalent to module.exports. Use default import.

formatter (CJS)

wrong

const { formatter } = require('eslint-friendly-formatter')

correct

const formatter = require('eslint-friendly-formatter')

CommonJS: module.exports = function, so require() returns the function directly.

formatter (TypeScript)

wrong

import * as formatter from 'eslint-friendly-formatter'

correct

import formatter from 'eslint-friendly-formatter'

TypeScript: default import works for both ESM and CJS with esModuleInterop.

Quickstart

Demonstrates using eslint-friendly-formatter to format ESLint results for console output with clickable file links.

const formatter = require('eslint-friendly-formatter');
const results = [
  {
    filePath: 'src/index.js',
    messages: [
      {
        ruleId: 'no-unused-vars',
        severity: 2,
        message: 'foo is defined but never used',
        line: 5,
        column: 10,
        nodeType: 'Identifier',
      },
    ],
    errorCount: 1,
    warningCount: 0,
    fixableErrorCount: 0,
    fixableWarningCount: 0,
    source: 'const foo = 1;',
  },
];
const output = formatter(results);
console.log(output);