babel-preset-blueflag

1.0.1 verified Sat Apr 25 auth: no javascript

A Babel preset encapsulating Blue Flag's opinionated configuration for transpiling JavaScript. Version 1.0.1, seems to be a single release. It automatically uses babel-preset-env to target either the last 2 browser versions or current Node.js, and includes plugins for runtime, class properties, stage-3, and React. Configuration options allow disabling specific plugins/presets and passing custom options to child presets. No updates since initial release, likely stable/small user base.

Common errors

error Error: Plugin/Preset files are not allowed to export objects, only functions. ↓

cause Using an outdated Babel version that expects function presets.

fix

Upgrade to Babel 7+ or ensure preset is loaded correctly.

error Module not found: Error: Can't resolve 'babel-preset-env' ↓

cause babel-preset-env is not installed as a direct dependency when using npm v7+ with auto-peer-deps off.

fix

Run npm install babel-preset-env --save-dev.

Warnings

deprecated babel-preset-stage-3 is deprecated in Babel 7+ ↓

fix Replace with individual plugins or @babel/preset-env with proposals.

gotcha Option 'library' currently does nothing ↓

fix Ignore or remove 'library' configuration until implemented.

gotcha Disabled array requires plugin/preset names without prefix ↓

fix Use 'react', not 'babel-preset-react'.

Install

npm install babel-preset-blueflag

yarn add babel-preset-blueflag

pnpm add babel-preset-blueflag

Imports

babel-preset-blueflag
wrong
```
{ presets: ['babel-preset-blueflag'] }
```
correct
```
{ presets: ['blueflag'] }
```
Use the shorthand 'blueflag' in Babel config.

default config

wrong

module.exports = { presets: ['blueflag', { browser: true }] }

correct

module.exports = { presets: [['blueflag', { browser: true }]] }

Options must be in an array: ['blueflag', options].

disabled plugins
wrong
```
['blueflag', { disabled: ['babel-preset-react'] }]
```
correct
```
['blueflag', { disabled: ['react'] }]
```
Prefixes like 'babel-preset-' or 'babel-plugin-' are omitted in the disabled list.

Quickstart

Shows how to install and configure babel-preset-blueflag with browser targeting, disabled array, and custom env targets.

// Install: npm install --save babel-preset-blueflag
// In .babelrc or babel.config.js:
module.exports = {
  presets: [
    ['blueflag', {
      browser: process.env.BROWSER === 'true',
      disabled: [],
      config: {
        env: {
          targets: {
            browsers: '> 1%'
          }
        }
      }
    }]
  ]
};