babel-preset-umeboshi

babel-preset-umeboshi

Standard Babel preset for Umeboshi templates

This preset includes:

• babel-preset-env with loose=true and useBuiltIns='entry' options. Target browsers: ['> 0.25%', 'not op_mini all', 'not ie < 11']
• babel-preset-stage-2
• transform-runtime plugin excluding polyfill.
• transform-es2015-modules-commonjs on test environments (BABEL_ENV = 'test' or NODE_ENV = 'test')

Regenerator transform and generator polyfill are always included in order to support async/await and dynamic imports. If you won't use these features and wish to save some KB you can disable them via preset options.

Install

With npm:

npm install --save-dev babel-preset-umeboshi

Or yarn:

yarn add babel-preset-umeboshi --dev

Usage

Add the preset to .babelrc file in your project's root folder.

{
  "presets": ["umeboshi"]
}

Preset options

Async support for legacy environment

By default both async/await and async import() are supported. Anyway in order to support older environments the preset needs to transpile them to generators and include the related runtime. This will result in an increased bundle size.
If you plan not to use such features, or your target browsers already support them, you can disable transpilation by the following setup:

{
  "presets": [
      ["umeboshi", {
          async: false,
          asyncImport: false
    }]
  ]
}

Custom browserslist query

By default this plugin sets browserslist's support to ['> 0.25%', 'not op_mini all', 'not ie < 11']. If you wish to use a different setup or prefer another source for queries, just set browserslist option to false:

{
  "presets": [
      ["umeboshi", {
          browserslist: false
    }]
  ]
}