babel-plugin-transform-dev

2.0.1 verified Sat Apr 25 auth: no javascript maintenance

Babel v6 plugin that replaces all occurrences of __DEV__ with the evaluation of "production" !== process.env.NODE_ENV. Currently at version 2.0.1, with no recent updates. It simplifies stripping development-only code from production bundles. Unlike similar plugins, it evaluates the expression at build time, replacing __DEV__ with a boolean literal. Limited to Babel v6; unmaintained since 2018. Use @babel/plugin-transform-dotenv or custom plugins for modern Babel.

Common errors

error Plugin/transform-dev is not a valid plugin ↓

cause Using with Babel v7+ which does not support this plugin.

fix

Switch to @babel/plugin-transform-dev or another alternative.

error ReferenceError: __DEV__ is not defined ↓

cause Plugin did not transform __DEV__ because it wasn't applied.

fix

Verify plugin is included in .babelrc and Babel is running correctly.

error TypeError: Cannot read property 'evaluate' of undefined ↓

cause Incorrect plugin configuration syntax in .babelrc.

fix

Use array syntax: ['transform-dev', { evaluate: false }].

Warnings

breaking Package is designed for Babel v6 only; does not work with Babel v7+. ↓

fix Use @babel/plugin-transform-dev or a custom plugin for Babel v7+.

deprecated Last release 2018; no active maintenance or security updates. ↓

fix Consider alternatives like @babel/plugin-transform-dotenv or custom babel macros.

gotcha Assumes process.env.NODE_ENV is set; otherwise __DEV__ is always true. ↓

fix Ensure your build system defines NODE_ENV (e.g., 'production' via webpack DefinePlugin).

Install

npm install babel-plugin-transform-dev

yarn add babel-plugin-transform-dev

pnpm add babel-plugin-transform-dev

Imports

default

wrong

const plugin = require('babel-plugin-transform-dev')

correct

import plugin from 'babel-plugin-transform-dev'

ESM import works; require also valid as this package does not enforce ESM-only.

N/A (Plugin Usage)

wrong

module.exports = { plugins: ['babel-plugin-transform-dev'] }

correct

module.exports = { plugins: ['transform-dev'] }

Babel resolves plugin names automatically; prefix not needed in .babelrc.

N/A (Plugin Options)

wrong

module.exports = { plugins: ['transform-dev'], options: { evaluate: false } }

correct

module.exports = { plugins: [['transform-dev', { evaluate: false }]] }

Options are passed as array elements; separate 'options' key is invalid.

Quickstart

Demonstrates replacing __DEV__ with a boolean based on environment variable.

// install: npm install babel-plugin-transform-dev
// .babelrc
{
  "plugins": ["transform-dev"]
}

// input.js
const isDev = __DEV__;
if (__DEV__) {
  console.log('dev only');
}

// output (with NODE_ENV=production)
const isDev = false;
if (false) {
  console.log('dev only');
}