eslint-plugin-filenames

1.3.2 verified Sat Apr 25 auth: no javascript maintenance

An ESLint plugin that enforces consistent filenames for JavaScript files. Current stable version is 1.3.2 (last updated 2019). It provides three rules: `match-regex` for custom regex patterns, `match-exported` to align filename with the default export, and `no-index` to disallow `index.js` files. The plugin only lints `.js` and `.jsx` files that ESLint processes. Unlike alternatives like `eslint-plugin-filenames-simple` or `eslint-plugin-unicorn`'s filename rule, this one is lightweight and focused, but note it is not actively maintained.

Common errors

error ESLint couldn't find the plugin "eslint-plugin-filenames" ↓

cause Plugin is not installed or not in node_modules.

fix

Run npm install eslint-plugin-filenames --save-dev and ensure it's in the same directory as your .eslintrc.

error Configuration for rule "filenames/match-regex" is invalid: Value [2, "^[a-z_]+$"] is not a valid severity. ↓

cause Severity must be a number or string like 'error', not an array if not using options.

fix

Use a number for severity if no options: "filenames/match-regex": 2. If using options, keep array format but ensure first element is severity: [2, "^[a-z_]+$"].

error Cannot read property 'match' of undefined ↓

cause Plugin not properly registered; eslint cannot access rules.

fix

Add 'filenames' to the plugins array in your ESLint config.

Warnings

gotcha Plugin only lints files that ESLint processes; non-JS/JSX files are ignored. ↓

fix Ensure all files you want to lint are included in ESLint's --ext or config.

deprecated Package is no longer actively maintained; last release in 2019. ↓

fix Consider migrating to eslint-plugin-simple-filenames or eslint-plugin-unicorn's filename rule.

gotcha match-exported rule does not respect exported function calls; it only matches names of default exports. ↓

fix Use only default export patterns like function, class, or variable declarations.

gotcha match-exported with multiple transforms: use null for no transform (not omitted). ↓

fix Example: [2, [null, 'kebab', 'snake']] instead of [2, ['kebab', 'snake']].

Install

npm install eslint-plugin-filenames

yarn add eslint-plugin-filenames

pnpm add eslint-plugin-filenames

Imports

plugin
wrong
```
require('eslint-plugin-filenames') without registering
```
correct
```
plugins: ['filenames'] in .eslintrc
```
This is an ESLint plugin, not an importable module in code. Register it in your ESLint config under 'plugins'.
match-regex
wrong
```
rules: { 'filenames/match-regex': 'error' } (missing array)
```
correct
```
rules: { 'filenames/match-regex': [2, '^[a-z_]+$'] }
```
The rule accepts an array with regex pattern and optional boolean for ignoring exported files.

match-exported

wrong

rules: { 'filenames/match-exported': [2, 'camel'] } (transform names are lowercase strings, e.g. 'camel', 'kebab')

correct

rules: { 'filenames/match-exported': 2 }

Transform parameter can be a string, an array of strings/null, or omitted. Use null for no transform.

no-index

wrong

rules: { 'filenames/no-index': 'error' } (should be numeric severity)

correct

rules: { 'filenames/no-index': 2 }

Simple rule; no options. Just set severity.

all rules

wrong

import plugin from 'eslint-plugin-filenames' (ESM not supported)

correct

const plugin = require('eslint-plugin-filenames'); plugin.rules

This package is CommonJS only; ESM import may fail in Node.js without bundler.

Quickstart

Shows installation, ESLint configuration with all three rules, and a test that triggers match-regex.

// 1. Install the plugin and ESLint
// npm install eslint eslint-plugin-filenames --save-dev

// 2. Create .eslintrc.json:
{
  "plugins": ["filenames"],
  "rules": {
    "filenames/match-regex": [2, "^[a-z_]+$"],
    "filenames/match-exported": [2, null, "\\.react$"],
    "filenames/no-index": 2
  }
}

// 3. Create a file test-foo.js (not matching regex) and run:
// npx eslint test-foo.js
// Expected output: error: Filename does not match the naming convention (filenames/match-regex)