Registry / devops / babel-plugin-remove-unused-vars

babel-plugin-remove-unused-vars

library2.2.0jsnpmunverified

A Babel plugin that automatically removes unused variables, imports, function arguments, and destructured bindings from JavaScript code, acting as a Babel-based autofix for ESLint's no-unused-vars rule. As of version 2.2.0, it supports source-to-source transformations and is intended for use as a build tool to clean up code. The plugin runs via Babel CLI or programmatically and handles common cases but has known limitations with deep assignment expressions. It is released under the MIT license with moderate maintenance cadence on GitHub, positioned as a more aggressive alternative to manual lint fixes or tree-shaking.

devops

npm install babel-plugin-remove-unused-vars

github ↗package ↗

INSTALL

IMPORT

SIG · BABEL-PLUGIN-REMOV

babel-plugin-remove-unused-vars

devopsjavascriptv2.2.0

Install

—

Import

—

Disk

—

Pass rate

0/ 6

Env Coverage0 / 6

glibc

18–22

musl

18–22

Install & Compatibility

Where this runs

tested against v? · npm install

Install × environment matrix

Each cell = how many times install + import succeeded across repeated harness runs. Partial = flaky.
glibc = Debian/Ubuntu slim · musl = Alpine Linux

musl

node 18–226 runs

build_error

glibc

node 18–226 runs

build_error

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

default

✓ module.exports = require('babel-plugin-remove-unused-vars')

✗ import plugin from 'babel-plugin-remove-unused-vars'

Plugin is CommonJS only; use require() in .babelrc or babel.config.js

PluginObj

✓ const plugin = require('babel-plugin-remove-unused-vars')

✗ import { PluginObj } from 'babel-plugin-remove-unused-vars'

No named exports; use default require

programmatic usage

✓ const babel = require('@babel/core'); const plugin = require('babel-plugin-remove-unused-vars'); babel.transformSync(code, { plugins: [plugin] })

✗ babel.transformSync(code, { plugins: ['babel-plugin-remove-unused-vars'] })

When using programmatically, pass the plugin function reference, not a string

Shows installation, configuration, CLI usage, and a simple transformation that removes unused imports and variables.

// Install: npm install --save-dev babel-plugin-remove-unused-vars // .babelrc { "plugins": ["babel-plugin-remove-unused-vars"] } // Or via CLI: // npx babel --no-babelrc --retain-lines --plugins babel-plugin-remove-unused-vars --out-dir dist/ src/ // Input: src/index.js import { unused } from './utils'; const a = 1; const b = a; console.log(b); // Output: dist/index.js import {} from './utils'; const b = 1; console.log(b);

Debug

Known issues

gotchaPlugin may produce false positives (removing actually used variables) or false negatives (keeping unused variables). Always review git diff after transformation.

fix

Run locally, inspect output with 'git diff', revert false removals manually.

affects: >=0.0.0

gotchaDeep assignment expressions (e.g., const a = foo(b = something())) are not fully handled. The right side may be removed even if the left side is used.

fix

Avoid deep assignments, or manually adjust after transformation.

affects: >=0.0.0

gotchaPlugin is intended for source-to-source transformation, not for minification or bundling. It should be run early in the build pipeline.

fix

Run before other transformations like minification.

affects: >=0.0.0

Errors

Common errors & fixes

Error: Cannot find module 'babel-plugin-remove-unused-vars'

Plugin not installed or not in node_modules.

fix

Run 'npm install --save-dev babel-plugin-remove-unused-vars' and ensure working directory has node_modules.

TypeError: babel.transformSync is not a function

Using a string plugin name instead of the plugin function reference when calling Babel programmatically.

fix

Use: babel.transformSync(code, { plugins: [require('babel-plugin-remove-unused-vars')] })

Unexpected token (1:0) when running Babel with --no-babelrc

Missing @babel/preset-env or other presets; --no-babelrc disables .babelrc but the plugin alone doesn't parse modern syntax.

fix

Add presets explicitly: npx babel --no-babelrc --presets @babel/preset-env --plugins babel-plugin-remove-unused-vars

Upgrade

Version history

2.2.0latest on npm

Audit

Dependencies

@babel/corerequiredRuntime dependency for Babel plugin execution

Agent activity

6 hits · last 30 days

node

Resources

githubhttps://github.com/steelbrain/babel-plugin-remove-unused-vars ↗

packagehttps://www.npmjs.com/package/babel-plugin-remove-unused-vars ↗